| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Security-Enhanced Linux (SELinux) security module |
| * |
| * This file contains the SELinux hook function implementations. |
| * |
| * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> |
| * Chris Vance, <cvance@nai.com> |
| * Wayne Salamon, <wsalamon@nai.com> |
| * James Morris <jmorris@redhat.com> |
| * |
| * Copyright (C) 2001,2002 Networks Associates Technology, Inc. |
| * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
| * Eric Paris <eparis@redhat.com> |
| * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
| * <dgoeddel@trustedcs.com> |
| * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
| * Paul Moore <paul@paul-moore.com> |
| * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
| * Yuichi Nakamura <ynakam@hitachisoft.jp> |
| * Copyright (C) 2016 Mellanox Technologies |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/kd.h> |
| #include <linux/kernel.h> |
| #include <linux/kernel_read_file.h> |
| #include <linux/errno.h> |
| #include <linux/sched/signal.h> |
| #include <linux/sched/task.h> |
| #include <linux/lsm_hooks.h> |
| #include <linux/xattr.h> |
| #include <linux/capability.h> |
| #include <linux/unistd.h> |
| #include <linux/mm.h> |
| #include <linux/mman.h> |
| #include <linux/slab.h> |
| #include <linux/pagemap.h> |
| #include <linux/proc_fs.h> |
| #include <linux/swap.h> |
| #include <linux/spinlock.h> |
| #include <linux/syscalls.h> |
| #include <linux/dcache.h> |
| #include <linux/file.h> |
| #include <linux/fdtable.h> |
| #include <linux/namei.h> |
| #include <linux/mount.h> |
| #include <linux/fs_context.h> |
| #include <linux/fs_parser.h> |
| #include <linux/netfilter_ipv4.h> |
| #include <linux/netfilter_ipv6.h> |
| #include <linux/tty.h> |
| #include <net/icmp.h> |
| #include <net/ip.h> /* for local_port_range[] */ |
| #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
| #include <net/inet_connection_sock.h> |
| #include <net/net_namespace.h> |
| #include <net/netlabel.h> |
| #include <linux/uaccess.h> |
| #include <asm/ioctls.h> |
| #include <linux/atomic.h> |
| #include <linux/bitops.h> |
| #include <linux/interrupt.h> |
| #include <linux/netdevice.h> /* for network interface checks */ |
| #include <net/netlink.h> |
| #include <linux/tcp.h> |
| #include <linux/udp.h> |
| #include <linux/dccp.h> |
| #include <linux/sctp.h> |
| #include <net/sctp/structs.h> |
| #include <linux/quota.h> |
| #include <linux/un.h> /* for Unix socket types */ |
| #include <net/af_unix.h> /* for Unix socket types */ |
| #include <linux/parser.h> |
| #include <linux/nfs_mount.h> |
| #include <net/ipv6.h> |
| #include <linux/hugetlb.h> |
| #include <linux/personality.h> |
| #include <linux/audit.h> |
| #include <linux/string.h> |
| #include <linux/mutex.h> |
| #include <linux/posix-timers.h> |
| #include <linux/syslog.h> |
| #include <linux/user_namespace.h> |
| #include <linux/export.h> |
| #include <linux/msg.h> |
| #include <linux/shm.h> |
| #include <uapi/linux/shm.h> |
| #include <linux/bpf.h> |
| #include <linux/kernfs.h> |
| #include <linux/stringhash.h> /* for hashlen_string() */ |
| #include <uapi/linux/mount.h> |
| #include <linux/fsnotify.h> |
| #include <linux/fanotify.h> |
| #include <linux/io_uring/cmd.h> |
| #include <uapi/linux/lsm.h> |
| |
| #include "avc.h" |
| #include "objsec.h" |
| #include "netif.h" |
| #include "netnode.h" |
| #include "netport.h" |
| #include "ibpkey.h" |
| #include "xfrm.h" |
| #include "netlabel.h" |
| #include "audit.h" |
| #include "avc_ss.h" |
| |
| #define SELINUX_INODE_INIT_XATTRS 1 |
| |
| struct selinux_state selinux_state; |
| |
| /* SECMARK reference count */ |
| static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
| |
| #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
| static int selinux_enforcing_boot __initdata; |
| |
| static int __init enforcing_setup(char *str) |
| { |
| unsigned long enforcing; |
| if (!kstrtoul(str, 0, &enforcing)) |
| selinux_enforcing_boot = enforcing ? 1 : 0; |
| return 1; |
| } |
| __setup("enforcing=", enforcing_setup); |
| #else |
| #define selinux_enforcing_boot 1 |
| #endif |
| |
| int selinux_enabled_boot __initdata = 1; |
| #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM |
| static int __init selinux_enabled_setup(char *str) |
| { |
| unsigned long enabled; |
| if (!kstrtoul(str, 0, &enabled)) |
| selinux_enabled_boot = enabled ? 1 : 0; |
| return 1; |
| } |
| __setup("selinux=", selinux_enabled_setup); |
| #endif |
| |
| static int __init checkreqprot_setup(char *str) |
| { |
| unsigned long checkreqprot; |
| |
| if (!kstrtoul(str, 0, &checkreqprot)) { |
| if (checkreqprot) |
| pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); |
| } |
| return 1; |
| } |
| __setup("checkreqprot=", checkreqprot_setup); |
| |
| /** |
| * selinux_secmark_enabled - Check to see if SECMARK is currently enabled |
| * |
| * Description: |
| * This function checks the SECMARK reference counter to see if any SECMARK |
| * targets are currently configured, if the reference counter is greater than |
| * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is |
| * enabled, false (0) if SECMARK is disabled. If the always_check_network |
| * policy capability is enabled, SECMARK is always considered enabled. |
| * |
| */ |
| static int selinux_secmark_enabled(void) |
| { |
| return (selinux_policycap_alwaysnetwork() || |
| atomic_read(&selinux_secmark_refcount)); |
| } |
| |
| /** |
| * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled |
| * |
| * Description: |
| * This function checks if NetLabel or labeled IPSEC is enabled. Returns true |
| * (1) if any are enabled or false (0) if neither are enabled. If the |
| * always_check_network policy capability is enabled, peer labeling |
| * is always considered enabled. |
| * |
| */ |
| static int selinux_peerlbl_enabled(void) |
| { |
| return (selinux_policycap_alwaysnetwork() || |
| netlbl_enabled() || selinux_xfrm_enabled()); |
| } |
| |
| static int selinux_netcache_avc_callback(u32 event) |
| { |
| if (event == AVC_CALLBACK_RESET) { |
| sel_netif_flush(); |
| sel_netnode_flush(); |
| sel_netport_flush(); |
| synchronize_net(); |
| } |
| return 0; |
| } |
| |
| static int selinux_lsm_notifier_avc_callback(u32 event) |
| { |
| if (event == AVC_CALLBACK_RESET) { |
| sel_ib_pkey_flush(); |
| call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * initialise the security for the init task |
| */ |
| static void cred_init_security(void) |
| { |
| struct task_security_struct *tsec; |
| |
| tsec = selinux_cred(unrcu_pointer(current->real_cred)); |
| tsec->osid = tsec->sid = SECINITSID_KERNEL; |
| } |
| |
| /* |
| * get the security ID of a set of credentials |
| */ |
| static inline u32 cred_sid(const struct cred *cred) |
| { |
| const struct task_security_struct *tsec; |
| |
| tsec = selinux_cred(cred); |
| return tsec->sid; |
| } |
| |
| static void __ad_net_init(struct common_audit_data *ad, |
| struct lsm_network_audit *net, |
| int ifindex, struct sock *sk, u16 family) |
| { |
| ad->type = LSM_AUDIT_DATA_NET; |
| ad->u.net = net; |
| net->netif = ifindex; |
| net->sk = sk; |
| net->family = family; |
| } |
| |
| static void ad_net_init_from_sk(struct common_audit_data *ad, |
| struct lsm_network_audit *net, |
| struct sock *sk) |
| { |
| __ad_net_init(ad, net, 0, sk, 0); |
| } |
| |
| static void ad_net_init_from_iif(struct common_audit_data *ad, |
| struct lsm_network_audit *net, |
| int ifindex, u16 family) |
| { |
| __ad_net_init(ad, net, ifindex, NULL, family); |
| } |
| |
| /* |
| * get the objective security ID of a task |
| */ |
| static inline u32 task_sid_obj(const struct task_struct *task) |
| { |
| u32 sid; |
| |
| rcu_read_lock(); |
| sid = cred_sid(__task_cred(task)); |
| rcu_read_unlock(); |
| return sid; |
| } |
| |
| static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
| |
| /* |
| * Try reloading inode security labels that have been marked as invalid. The |
| * @may_sleep parameter indicates when sleeping and thus reloading labels is |
| * allowed; when set to false, returns -ECHILD when the label is |
| * invalid. The @dentry parameter should be set to a dentry of the inode. |
| */ |
| static int __inode_security_revalidate(struct inode *inode, |
| struct dentry *dentry, |
| bool may_sleep) |
| { |
| struct inode_security_struct *isec = selinux_inode(inode); |
| |
| might_sleep_if(may_sleep); |
| |
| if (selinux_initialized() && |
| isec->initialized != LABEL_INITIALIZED) { |
| if (!may_sleep) |
| return -ECHILD; |
| |
| /* |
| * Try reloading the inode security label. This will fail if |
| * @opt_dentry is NULL and no dentry for this inode can be |
| * found; in that case, continue using the old label. |
| */ |
| inode_doinit_with_dentry(inode, dentry); |
| } |
| return 0; |
| } |
| |
| static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
| { |
| return selinux_inode(inode); |
| } |
| |
| static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) |
| { |
| int error; |
| |
| error = __inode_security_revalidate(inode, NULL, !rcu); |
| if (error) |
| return ERR_PTR(error); |
| return selinux_inode(inode); |
| } |
| |
| /* |
| * Get the security label of an inode. |
| */ |
| static struct inode_security_struct *inode_security(struct inode *inode) |
| { |
| __inode_security_revalidate(inode, NULL, true); |
| return selinux_inode(inode); |
| } |
| |
| static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
| { |
| struct inode *inode = d_backing_inode(dentry); |
| |
| return selinux_inode(inode); |
| } |
| |
| /* |
| * Get the security label of a dentry's backing inode. |
| */ |
| static struct inode_security_struct *backing_inode_security(struct dentry *dentry) |
| { |
| struct inode *inode = d_backing_inode(dentry); |
| |
| __inode_security_revalidate(inode, dentry, true); |
| return selinux_inode(inode); |
| } |
| |
| static void inode_free_security(struct inode *inode) |
| { |
| struct inode_security_struct *isec = selinux_inode(inode); |
| struct superblock_security_struct *sbsec; |
| |
| if (!isec) |
| return; |
| sbsec = selinux_superblock(inode->i_sb); |
| /* |
| * As not all inode security structures are in a list, we check for |
| * empty list outside of the lock to make sure that we won't waste |
| * time taking a lock doing nothing. |
| * |
| * The list_del_init() function can be safely called more than once. |
| * It should not be possible for this function to be called with |
| * concurrent list_add(), but for better safety against future changes |
| * in the code, we use list_empty_careful() here. |
| */ |
| if (!list_empty_careful(&isec->list)) { |
| spin_lock(&sbsec->isec_lock); |
| list_del_init(&isec->list); |
| spin_unlock(&sbsec->isec_lock); |
| } |
| } |
| |
| struct selinux_mnt_opts { |
| u32 fscontext_sid; |
| u32 context_sid; |
| u32 rootcontext_sid; |
| u32 defcontext_sid; |
| }; |
| |
| static void selinux_free_mnt_opts(void *mnt_opts) |
| { |
| kfree(mnt_opts); |
| } |
| |
| enum { |
| Opt_error = -1, |
| Opt_context = 0, |
| Opt_defcontext = 1, |
| Opt_fscontext = 2, |
| Opt_rootcontext = 3, |
| Opt_seclabel = 4, |
| }; |
| |
| #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} |
| static const struct { |
| const char *name; |
| int len; |
| int opt; |
| bool has_arg; |
| } tokens[] = { |
| A(context, true), |
| A(fscontext, true), |
| A(defcontext, true), |
| A(rootcontext, true), |
| A(seclabel, false), |
| }; |
| #undef A |
| |
| static int match_opt_prefix(char *s, int l, char **arg) |
| { |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(tokens); i++) { |
| size_t len = tokens[i].len; |
| if (len > l || memcmp(s, tokens[i].name, len)) |
| continue; |
| if (tokens[i].has_arg) { |
| if (len == l || s[len] != '=') |
| continue; |
| *arg = s + len + 1; |
| } else if (len != l) |
| continue; |
| return tokens[i].opt; |
| } |
| return Opt_error; |
| } |
| |
| #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" |
| |
| static int may_context_mount_sb_relabel(u32 sid, |
| struct superblock_security_struct *sbsec, |
| const struct cred *cred) |
| { |
| const struct task_security_struct *tsec = selinux_cred(cred); |
| int rc; |
| |
| rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__RELABELFROM, NULL); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__RELABELTO, NULL); |
| return rc; |
| } |
| |
| static int may_context_mount_inode_relabel(u32 sid, |
| struct superblock_security_struct *sbsec, |
| const struct cred *cred) |
| { |
| const struct task_security_struct *tsec = selinux_cred(cred); |
| int rc; |
| rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__RELABELFROM, NULL); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__ASSOCIATE, NULL); |
| return rc; |
| } |
| |
| static int selinux_is_genfs_special_handling(struct super_block *sb) |
| { |
| /* Special handling. Genfs but also in-core setxattr handler */ |
| return !strcmp(sb->s_type->name, "sysfs") || |
| !strcmp(sb->s_type->name, "pstore") || |
| !strcmp(sb->s_type->name, "debugfs") || |
| !strcmp(sb->s_type->name, "tracefs") || |
| !strcmp(sb->s_type->name, "rootfs") || |
| (selinux_policycap_cgroupseclabel() && |
| (!strcmp(sb->s_type->name, "cgroup") || |
| !strcmp(sb->s_type->name, "cgroup2"))); |
| } |
| |
| static int selinux_is_sblabel_mnt(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| |
| /* |
| * IMPORTANT: Double-check logic in this function when adding a new |
| * SECURITY_FS_USE_* definition! |
| */ |
| BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); |
| |
| switch (sbsec->behavior) { |
| case SECURITY_FS_USE_XATTR: |
| case SECURITY_FS_USE_TRANS: |
| case SECURITY_FS_USE_TASK: |
| case SECURITY_FS_USE_NATIVE: |
| return 1; |
| |
| case SECURITY_FS_USE_GENFS: |
| return selinux_is_genfs_special_handling(sb); |
| |
| /* Never allow relabeling on context mounts */ |
| case SECURITY_FS_USE_MNTPOINT: |
| case SECURITY_FS_USE_NONE: |
| default: |
| return 0; |
| } |
| } |
| |
| static int sb_check_xattr_support(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| struct dentry *root = sb->s_root; |
| struct inode *root_inode = d_backing_inode(root); |
| u32 sid; |
| int rc; |
| |
| /* |
| * Make sure that the xattr handler exists and that no |
| * error other than -ENODATA is returned by getxattr on |
| * the root directory. -ENODATA is ok, as this may be |
| * the first boot of the SELinux kernel before we have |
| * assigned xattr values to the filesystem. |
| */ |
| if (!(root_inode->i_opflags & IOP_XATTR)) { |
| pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", |
| sb->s_id, sb->s_type->name); |
| goto fallback; |
| } |
| |
| rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); |
| if (rc < 0 && rc != -ENODATA) { |
| if (rc == -EOPNOTSUPP) { |
| pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", |
| sb->s_id, sb->s_type->name); |
| goto fallback; |
| } else { |
| pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", |
| sb->s_id, sb->s_type->name, -rc); |
| return rc; |
| } |
| } |
| return 0; |
| |
| fallback: |
| /* No xattr support - try to fallback to genfs if possible. */ |
| rc = security_genfs_sid(sb->s_type->name, "/", |
| SECCLASS_DIR, &sid); |
| if (rc) |
| return -EOPNOTSUPP; |
| |
| pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", |
| sb->s_id, sb->s_type->name); |
| sbsec->behavior = SECURITY_FS_USE_GENFS; |
| sbsec->sid = sid; |
| return 0; |
| } |
| |
| static int sb_finish_set_opts(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| struct dentry *root = sb->s_root; |
| struct inode *root_inode = d_backing_inode(root); |
| int rc = 0; |
| |
| if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
| rc = sb_check_xattr_support(sb); |
| if (rc) |
| return rc; |
| } |
| |
| sbsec->flags |= SE_SBINITIALIZED; |
| |
| /* |
| * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply |
| * leave the flag untouched because sb_clone_mnt_opts might be handing |
| * us a superblock that needs the flag to be cleared. |
| */ |
| if (selinux_is_sblabel_mnt(sb)) |
| sbsec->flags |= SBLABEL_MNT; |
| else |
| sbsec->flags &= ~SBLABEL_MNT; |
| |
| /* Initialize the root inode. */ |
| rc = inode_doinit_with_dentry(root_inode, root); |
| |
| /* Initialize any other inodes associated with the superblock, e.g. |
| inodes created prior to initial policy load or inodes created |
| during get_sb by a pseudo filesystem that directly |
| populates itself. */ |
| spin_lock(&sbsec->isec_lock); |
| while (!list_empty(&sbsec->isec_head)) { |
| struct inode_security_struct *isec = |
| list_first_entry(&sbsec->isec_head, |
| struct inode_security_struct, list); |
| struct inode *inode = isec->inode; |
| list_del_init(&isec->list); |
| spin_unlock(&sbsec->isec_lock); |
| inode = igrab(inode); |
| if (inode) { |
| if (!IS_PRIVATE(inode)) |
| inode_doinit_with_dentry(inode, NULL); |
| iput(inode); |
| } |
| spin_lock(&sbsec->isec_lock); |
| } |
| spin_unlock(&sbsec->isec_lock); |
| return rc; |
| } |
| |
| static int bad_option(struct superblock_security_struct *sbsec, char flag, |
| u32 old_sid, u32 new_sid) |
| { |
| char mnt_flags = sbsec->flags & SE_MNTMASK; |
| |
| /* check if the old mount command had the same options */ |
| if (sbsec->flags & SE_SBINITIALIZED) |
| if (!(sbsec->flags & flag) || |
| (old_sid != new_sid)) |
| return 1; |
| |
| /* check if we were passed the same options twice, |
| * aka someone passed context=a,context=b |
| */ |
| if (!(sbsec->flags & SE_SBINITIALIZED)) |
| if (mnt_flags & flag) |
| return 1; |
| return 0; |
| } |
| |
| /* |
| * Allow filesystems with binary mount data to explicitly set mount point |
| * labeling information. |
| */ |
| static int selinux_set_mnt_opts(struct super_block *sb, |
| void *mnt_opts, |
| unsigned long kern_flags, |
| unsigned long *set_kern_flags) |
| { |
| const struct cred *cred = current_cred(); |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| struct dentry *root = sb->s_root; |
| struct selinux_mnt_opts *opts = mnt_opts; |
| struct inode_security_struct *root_isec; |
| u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
| u32 defcontext_sid = 0; |
| int rc = 0; |
| |
| /* |
| * Specifying internal flags without providing a place to |
| * place the results is not allowed |
| */ |
| if (kern_flags && !set_kern_flags) |
| return -EINVAL; |
| |
| mutex_lock(&sbsec->lock); |
| |
| if (!selinux_initialized()) { |
| if (!opts) { |
| /* Defer initialization until selinux_complete_init, |
| after the initial policy is loaded and the security |
| server is ready to handle calls. */ |
| if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { |
| sbsec->flags |= SE_SBNATIVE; |
| *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
| } |
| goto out; |
| } |
| rc = -EINVAL; |
| pr_warn("SELinux: Unable to set superblock options " |
| "before the security server is initialized\n"); |
| goto out; |
| } |
| |
| /* |
| * Binary mount data FS will come through this function twice. Once |
| * from an explicit call and once from the generic calls from the vfs. |
| * Since the generic VFS calls will not contain any security mount data |
| * we need to skip the double mount verification. |
| * |
| * This does open a hole in which we will not notice if the first |
| * mount using this sb set explicit options and a second mount using |
| * this sb does not set any security options. (The first options |
| * will be used for both mounts) |
| */ |
| if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
| && !opts) |
| goto out; |
| |
| root_isec = backing_inode_security_novalidate(root); |
| |
| /* |
| * parse the mount options, check if they are valid sids. |
| * also check if someone is trying to mount the same sb more |
| * than once with different security options. |
| */ |
| if (opts) { |
| if (opts->fscontext_sid) { |
| fscontext_sid = opts->fscontext_sid; |
| if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
| fscontext_sid)) |
| goto out_double_mount; |
| sbsec->flags |= FSCONTEXT_MNT; |
| } |
| if (opts->context_sid) { |
| context_sid = opts->context_sid; |
| if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
| context_sid)) |
| goto out_double_mount; |
| sbsec->flags |= CONTEXT_MNT; |
| } |
| if (opts->rootcontext_sid) { |
| rootcontext_sid = opts->rootcontext_sid; |
| if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
| rootcontext_sid)) |
| goto out_double_mount; |
| sbsec->flags |= ROOTCONTEXT_MNT; |
| } |
| if (opts->defcontext_sid) { |
| defcontext_sid = opts->defcontext_sid; |
| if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
| defcontext_sid)) |
| goto out_double_mount; |
| sbsec->flags |= DEFCONTEXT_MNT; |
| } |
| } |
| |
| if (sbsec->flags & SE_SBINITIALIZED) { |
| /* previously mounted with options, but not on this attempt? */ |
| if ((sbsec->flags & SE_MNTMASK) && !opts) |
| goto out_double_mount; |
| rc = 0; |
| goto out; |
| } |
| |
| if (strcmp(sb->s_type->name, "proc") == 0) |
| sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
| |
| if (!strcmp(sb->s_type->name, "debugfs") || |
| !strcmp(sb->s_type->name, "tracefs") || |
| !strcmp(sb->s_type->name, "binder") || |
| !strcmp(sb->s_type->name, "bpf") || |
| !strcmp(sb->s_type->name, "pstore") || |
| !strcmp(sb->s_type->name, "securityfs")) |
| sbsec->flags |= SE_SBGENFS; |
| |
| if (!strcmp(sb->s_type->name, "sysfs") || |
| !strcmp(sb->s_type->name, "cgroup") || |
| !strcmp(sb->s_type->name, "cgroup2")) |
| sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; |
| |
| if (!sbsec->behavior) { |
| /* |
| * Determine the labeling behavior to use for this |
| * filesystem type. |
| */ |
| rc = security_fs_use(sb); |
| if (rc) { |
| pr_warn("%s: security_fs_use(%s) returned %d\n", |
| __func__, sb->s_type->name, rc); |
| goto out; |
| } |
| } |
| |
| /* |
| * If this is a user namespace mount and the filesystem type is not |
| * explicitly whitelisted, then no contexts are allowed on the command |
| * line and security labels must be ignored. |
| */ |
| if (sb->s_user_ns != &init_user_ns && |
| strcmp(sb->s_type->name, "tmpfs") && |
| strcmp(sb->s_type->name, "ramfs") && |
| strcmp(sb->s_type->name, "devpts") && |
| strcmp(sb->s_type->name, "overlay")) { |
| if (context_sid || fscontext_sid || rootcontext_sid || |
| defcontext_sid) { |
| rc = -EACCES; |
| goto out; |
| } |
| if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
| sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
| rc = security_transition_sid(current_sid(), |
| current_sid(), |
| SECCLASS_FILE, NULL, |
| &sbsec->mntpoint_sid); |
| if (rc) |
| goto out; |
| } |
| goto out_set_opts; |
| } |
| |
| /* sets the context of the superblock for the fs being mounted. */ |
| if (fscontext_sid) { |
| rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
| if (rc) |
| goto out; |
| |
| sbsec->sid = fscontext_sid; |
| } |
| |
| /* |
| * Switch to using mount point labeling behavior. |
| * sets the label used on all file below the mountpoint, and will set |
| * the superblock context if not already set. |
| */ |
| if (sbsec->flags & SE_SBNATIVE) { |
| /* |
| * This means we are initializing a superblock that has been |
| * mounted before the SELinux was initialized and the |
| * filesystem requested native labeling. We had already |
| * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags |
| * in the original mount attempt, so now we just need to set |
| * the SECURITY_FS_USE_NATIVE behavior. |
| */ |
| sbsec->behavior = SECURITY_FS_USE_NATIVE; |
| } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
| sbsec->behavior = SECURITY_FS_USE_NATIVE; |
| *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
| } |
| |
| if (context_sid) { |
| if (!fscontext_sid) { |
| rc = may_context_mount_sb_relabel(context_sid, sbsec, |
| cred); |
| if (rc) |
| goto out; |
| sbsec->sid = context_sid; |
| } else { |
| rc = may_context_mount_inode_relabel(context_sid, sbsec, |
| cred); |
| if (rc) |
| goto out; |
| } |
| if (!rootcontext_sid) |
| rootcontext_sid = context_sid; |
| |
| sbsec->mntpoint_sid = context_sid; |
| sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
| } |
| |
| if (rootcontext_sid) { |
| rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
| cred); |
| if (rc) |
| goto out; |
| |
| root_isec->sid = rootcontext_sid; |
| root_isec->initialized = LABEL_INITIALIZED; |
| } |
| |
| if (defcontext_sid) { |
| if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
| sbsec->behavior != SECURITY_FS_USE_NATIVE) { |
| rc = -EINVAL; |
| pr_warn("SELinux: defcontext option is " |
| "invalid for this filesystem type\n"); |
| goto out; |
| } |
| |
| if (defcontext_sid != sbsec->def_sid) { |
| rc = may_context_mount_inode_relabel(defcontext_sid, |
| sbsec, cred); |
| if (rc) |
| goto out; |
| } |
| |
| sbsec->def_sid = defcontext_sid; |
| } |
| |
| out_set_opts: |
| rc = sb_finish_set_opts(sb); |
| out: |
| mutex_unlock(&sbsec->lock); |
| return rc; |
| out_double_mount: |
| rc = -EINVAL; |
| pr_warn("SELinux: mount invalid. Same superblock, different " |
| "security settings for (dev %s, type %s)\n", sb->s_id, |
| sb->s_type->name); |
| goto out; |
| } |
| |
| static int selinux_cmp_sb_context(const struct super_block *oldsb, |
| const struct super_block *newsb) |
| { |
| struct superblock_security_struct *old = selinux_superblock(oldsb); |
| struct superblock_security_struct *new = selinux_superblock(newsb); |
| char oldflags = old->flags & SE_MNTMASK; |
| char newflags = new->flags & SE_MNTMASK; |
| |
| if (oldflags != newflags) |
| goto mismatch; |
| if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) |
| goto mismatch; |
| if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) |
| goto mismatch; |
| if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) |
| goto mismatch; |
| if (oldflags & ROOTCONTEXT_MNT) { |
| struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
| struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); |
| if (oldroot->sid != newroot->sid) |
| goto mismatch; |
| } |
| return 0; |
| mismatch: |
| pr_warn("SELinux: mount invalid. Same superblock, " |
| "different security settings for (dev %s, " |
| "type %s)\n", newsb->s_id, newsb->s_type->name); |
| return -EBUSY; |
| } |
| |
| static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
| struct super_block *newsb, |
| unsigned long kern_flags, |
| unsigned long *set_kern_flags) |
| { |
| int rc = 0; |
| const struct superblock_security_struct *oldsbsec = |
| selinux_superblock(oldsb); |
| struct superblock_security_struct *newsbsec = selinux_superblock(newsb); |
| |
| int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
| int set_context = (oldsbsec->flags & CONTEXT_MNT); |
| int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); |
| |
| /* |
| * Specifying internal flags without providing a place to |
| * place the results is not allowed. |
| */ |
| if (kern_flags && !set_kern_flags) |
| return -EINVAL; |
| |
| mutex_lock(&newsbsec->lock); |
| |
| /* |
| * if the parent was able to be mounted it clearly had no special lsm |
| * mount options. thus we can safely deal with this superblock later |
| */ |
| if (!selinux_initialized()) { |
| if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { |
| newsbsec->flags |= SE_SBNATIVE; |
| *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
| } |
| goto out; |
| } |
| |
| /* how can we clone if the old one wasn't set up?? */ |
| BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
| |
| /* if fs is reusing a sb, make sure that the contexts match */ |
| if (newsbsec->flags & SE_SBINITIALIZED) { |
| mutex_unlock(&newsbsec->lock); |
| if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) |
| *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
| return selinux_cmp_sb_context(oldsb, newsb); |
| } |
| |
| newsbsec->flags = oldsbsec->flags; |
| |
| newsbsec->sid = oldsbsec->sid; |
| newsbsec->def_sid = oldsbsec->def_sid; |
| newsbsec->behavior = oldsbsec->behavior; |
| |
| if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
| !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { |
| rc = security_fs_use(newsb); |
| if (rc) |
| goto out; |
| } |
| |
| if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { |
| newsbsec->behavior = SECURITY_FS_USE_NATIVE; |
| *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
| } |
| |
| if (set_context) { |
| u32 sid = oldsbsec->mntpoint_sid; |
| |
| if (!set_fscontext) |
| newsbsec->sid = sid; |
| if (!set_rootcontext) { |
| struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
| newisec->sid = sid; |
| } |
| newsbsec->mntpoint_sid = sid; |
| } |
| if (set_rootcontext) { |
| const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
| struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
| |
| newisec->sid = oldisec->sid; |
| } |
| |
| sb_finish_set_opts(newsb); |
| out: |
| mutex_unlock(&newsbsec->lock); |
| return rc; |
| } |
| |
| /* |
| * NOTE: the caller is responsible for freeing the memory even if on error. |
| */ |
| static int selinux_add_opt(int token, const char *s, void **mnt_opts) |
| { |
| struct selinux_mnt_opts *opts = *mnt_opts; |
| u32 *dst_sid; |
| int rc; |
| |
| if (token == Opt_seclabel) |
| /* eaten and completely ignored */ |
| return 0; |
| if (!s) |
| return -EINVAL; |
| |
| if (!selinux_initialized()) { |
| pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); |
| return -EINVAL; |
| } |
| |
| if (!opts) { |
| opts = kzalloc(sizeof(*opts), GFP_KERNEL); |
| if (!opts) |
| return -ENOMEM; |
| *mnt_opts = opts; |
| } |
| |
| switch (token) { |
| case Opt_context: |
| if (opts->context_sid || opts->defcontext_sid) |
| goto err; |
| dst_sid = &opts->context_sid; |
| break; |
| case Opt_fscontext: |
| if (opts->fscontext_sid) |
| goto err; |
| dst_sid = &opts->fscontext_sid; |
| break; |
| case Opt_rootcontext: |
| if (opts->rootcontext_sid) |
| goto err; |
| dst_sid = &opts->rootcontext_sid; |
| break; |
| case Opt_defcontext: |
| if (opts->context_sid || opts->defcontext_sid) |
| goto err; |
| dst_sid = &opts->defcontext_sid; |
| break; |
| default: |
| WARN_ON(1); |
| return -EINVAL; |
| } |
| rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); |
| if (rc) |
| pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", |
| s, rc); |
| return rc; |
| |
| err: |
| pr_warn(SEL_MOUNT_FAIL_MSG); |
| return -EINVAL; |
| } |
| |
| static int show_sid(struct seq_file *m, u32 sid) |
| { |
| char *context = NULL; |
| u32 len; |
| int rc; |
| |
| rc = security_sid_to_context(sid, &context, &len); |
| if (!rc) { |
| bool has_comma = strchr(context, ','); |
| |
| seq_putc(m, '='); |
| if (has_comma) |
| seq_putc(m, '\"'); |
| seq_escape(m, context, "\"\n\\"); |
| if (has_comma) |
| seq_putc(m, '\"'); |
| } |
| kfree(context); |
| return rc; |
| } |
| |
| static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| int rc; |
| |
| if (!(sbsec->flags & SE_SBINITIALIZED)) |
| return 0; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| if (sbsec->flags & FSCONTEXT_MNT) { |
| seq_putc(m, ','); |
| seq_puts(m, FSCONTEXT_STR); |
| rc = show_sid(m, sbsec->sid); |
| if (rc) |
| return rc; |
| } |
| if (sbsec->flags & CONTEXT_MNT) { |
| seq_putc(m, ','); |
| seq_puts(m, CONTEXT_STR); |
| rc = show_sid(m, sbsec->mntpoint_sid); |
| if (rc) |
| return rc; |
| } |
| if (sbsec->flags & DEFCONTEXT_MNT) { |
| seq_putc(m, ','); |
| seq_puts(m, DEFCONTEXT_STR); |
| rc = show_sid(m, sbsec->def_sid); |
| if (rc) |
| return rc; |
| } |
| if (sbsec->flags & ROOTCONTEXT_MNT) { |
| struct dentry *root = sb->s_root; |
| struct inode_security_struct *isec = backing_inode_security(root); |
| seq_putc(m, ','); |
| seq_puts(m, ROOTCONTEXT_STR); |
| rc = show_sid(m, isec->sid); |
| if (rc) |
| return rc; |
| } |
| if (sbsec->flags & SBLABEL_MNT) { |
| seq_putc(m, ','); |
| seq_puts(m, SECLABEL_STR); |
| } |
| return 0; |
| } |
| |
| static inline u16 inode_mode_to_security_class(umode_t mode) |
| { |
| switch (mode & S_IFMT) { |
| case S_IFSOCK: |
| return SECCLASS_SOCK_FILE; |
| case S_IFLNK: |
| return SECCLASS_LNK_FILE; |
| case S_IFREG: |
| return SECCLASS_FILE; |
| case S_IFBLK: |
| return SECCLASS_BLK_FILE; |
| case S_IFDIR: |
| return SECCLASS_DIR; |
| case S_IFCHR: |
| return SECCLASS_CHR_FILE; |
| case S_IFIFO: |
| return SECCLASS_FIFO_FILE; |
| |
| } |
| |
| return SECCLASS_FILE; |
| } |
| |
| static inline int default_protocol_stream(int protocol) |
| { |
| return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || |
| protocol == IPPROTO_MPTCP); |
| } |
| |
| static inline int default_protocol_dgram(int protocol) |
| { |
| return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); |
| } |
| |
| static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
| { |
| bool extsockclass = selinux_policycap_extsockclass(); |
| |
| switch (family) { |
| case PF_UNIX: |
| switch (type) { |
| case SOCK_STREAM: |
| case SOCK_SEQPACKET: |
| return SECCLASS_UNIX_STREAM_SOCKET; |
| case SOCK_DGRAM: |
| case SOCK_RAW: |
| return SECCLASS_UNIX_DGRAM_SOCKET; |
| } |
| break; |
| case PF_INET: |
| case PF_INET6: |
| switch (type) { |
| case SOCK_STREAM: |
| case SOCK_SEQPACKET: |
| if (default_protocol_stream(protocol)) |
| return SECCLASS_TCP_SOCKET; |
| else if (extsockclass && protocol == IPPROTO_SCTP) |
| return SECCLASS_SCTP_SOCKET; |
| else |
| return SECCLASS_RAWIP_SOCKET; |
| case SOCK_DGRAM: |
| if (default_protocol_dgram(protocol)) |
| return SECCLASS_UDP_SOCKET; |
| else if (extsockclass && (protocol == IPPROTO_ICMP || |
| protocol == IPPROTO_ICMPV6)) |
| return SECCLASS_ICMP_SOCKET; |
| else |
| return SECCLASS_RAWIP_SOCKET; |
| case SOCK_DCCP: |
| return SECCLASS_DCCP_SOCKET; |
| default: |
| return SECCLASS_RAWIP_SOCKET; |
| } |
| break; |
| case PF_NETLINK: |
| switch (protocol) { |
| case NETLINK_ROUTE: |
| return SECCLASS_NETLINK_ROUTE_SOCKET; |
| case NETLINK_SOCK_DIAG: |
| return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
| case NETLINK_NFLOG: |
| return SECCLASS_NETLINK_NFLOG_SOCKET; |
| case NETLINK_XFRM: |
| return SECCLASS_NETLINK_XFRM_SOCKET; |
| case NETLINK_SELINUX: |
| return SECCLASS_NETLINK_SELINUX_SOCKET; |
| case NETLINK_ISCSI: |
| return SECCLASS_NETLINK_ISCSI_SOCKET; |
| case NETLINK_AUDIT: |
| return SECCLASS_NETLINK_AUDIT_SOCKET; |
| case NETLINK_FIB_LOOKUP: |
| return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; |
| case NETLINK_CONNECTOR: |
| return SECCLASS_NETLINK_CONNECTOR_SOCKET; |
| case NETLINK_NETFILTER: |
| return SECCLASS_NETLINK_NETFILTER_SOCKET; |
| case NETLINK_DNRTMSG: |
| return SECCLASS_NETLINK_DNRT_SOCKET; |
| case NETLINK_KOBJECT_UEVENT: |
| return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; |
| case NETLINK_GENERIC: |
| return SECCLASS_NETLINK_GENERIC_SOCKET; |
| case NETLINK_SCSITRANSPORT: |
| return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; |
| case NETLINK_RDMA: |
| return SECCLASS_NETLINK_RDMA_SOCKET; |
| case NETLINK_CRYPTO: |
| return SECCLASS_NETLINK_CRYPTO_SOCKET; |
| default: |
| return SECCLASS_NETLINK_SOCKET; |
| } |
| case PF_PACKET: |
| return SECCLASS_PACKET_SOCKET; |
| case PF_KEY: |
| return SECCLASS_KEY_SOCKET; |
| case PF_APPLETALK: |
| return SECCLASS_APPLETALK_SOCKET; |
| } |
| |
| if (extsockclass) { |
| switch (family) { |
| case PF_AX25: |
| return SECCLASS_AX25_SOCKET; |
| case PF_IPX: |
| return SECCLASS_IPX_SOCKET; |
| case PF_NETROM: |
| return SECCLASS_NETROM_SOCKET; |
| case PF_ATMPVC: |
| return SECCLASS_ATMPVC_SOCKET; |
| case PF_X25: |
| return SECCLASS_X25_SOCKET; |
| case PF_ROSE: |
| return SECCLASS_ROSE_SOCKET; |
| case PF_DECnet: |
| return SECCLASS_DECNET_SOCKET; |
| case PF_ATMSVC: |
| return SECCLASS_ATMSVC_SOCKET; |
| case PF_RDS: |
| return SECCLASS_RDS_SOCKET; |
| case PF_IRDA: |
| return SECCLASS_IRDA_SOCKET; |
| case PF_PPPOX: |
| return SECCLASS_PPPOX_SOCKET; |
| case PF_LLC: |
| return SECCLASS_LLC_SOCKET; |
| case PF_CAN: |
| return SECCLASS_CAN_SOCKET; |
| case PF_TIPC: |
| return SECCLASS_TIPC_SOCKET; |
| case PF_BLUETOOTH: |
| return SECCLASS_BLUETOOTH_SOCKET; |
| case PF_IUCV: |
| return SECCLASS_IUCV_SOCKET; |
| case PF_RXRPC: |
| return SECCLASS_RXRPC_SOCKET; |
| case PF_ISDN: |
| return SECCLASS_ISDN_SOCKET; |
| case PF_PHONET: |
| return SECCLASS_PHONET_SOCKET; |
| case PF_IEEE802154: |
| return SECCLASS_IEEE802154_SOCKET; |
| case PF_CAIF: |
| return SECCLASS_CAIF_SOCKET; |
| case PF_ALG: |
| return SECCLASS_ALG_SOCKET; |
| case PF_NFC: |
| return SECCLASS_NFC_SOCKET; |
| case PF_VSOCK: |
| return SECCLASS_VSOCK_SOCKET; |
| case PF_KCM: |
| return SECCLASS_KCM_SOCKET; |
| case PF_QIPCRTR: |
| return SECCLASS_QIPCRTR_SOCKET; |
| case PF_SMC: |
| return SECCLASS_SMC_SOCKET; |
| case PF_XDP: |
| return SECCLASS_XDP_SOCKET; |
| case PF_MCTP: |
| return SECCLASS_MCTP_SOCKET; |
| #if PF_MAX > 46 |
| #error New address family defined, please update this function. |
| #endif |
| } |
| } |
| |
| return SECCLASS_SOCKET; |
| } |
| |
| static int selinux_genfs_get_sid(struct dentry *dentry, |
| u16 tclass, |
| u16 flags, |
| u32 *sid) |
| { |
| int rc; |
| struct super_block *sb = dentry->d_sb; |
| char *buffer, *path; |
| |
| buffer = (char *)__get_free_page(GFP_KERNEL); |
| if (!buffer) |
| return -ENOMEM; |
| |
| path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
| if (IS_ERR(path)) |
| rc = PTR_ERR(path); |
| else { |
| if (flags & SE_SBPROC) { |
| /* each process gets a /proc/PID/ entry. Strip off the |
| * PID part to get a valid selinux labeling. |
| * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ |
| while (path[1] >= '0' && path[1] <= '9') { |
| path[1] = '/'; |
| path++; |
| } |
| } |
| rc = security_genfs_sid(sb->s_type->name, |
| path, tclass, sid); |
| if (rc == -ENOENT) { |
| /* No match in policy, mark as unlabeled. */ |
| *sid = SECINITSID_UNLABELED; |
| rc = 0; |
| } |
| } |
| free_page((unsigned long)buffer); |
| return rc; |
| } |
| |
| static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, |
| u32 def_sid, u32 *sid) |
| { |
| #define INITCONTEXTLEN 255 |
| char *context; |
| unsigned int len; |
| int rc; |
| |
| len = INITCONTEXTLEN; |
| context = kmalloc(len + 1, GFP_NOFS); |
| if (!context) |
| return -ENOMEM; |
| |
| context[len] = '\0'; |
| rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
| if (rc == -ERANGE) { |
| kfree(context); |
| |
| /* Need a larger buffer. Query for the right size. */ |
| rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
| if (rc < 0) |
| return rc; |
| |
| len = rc; |
| context = kmalloc(len + 1, GFP_NOFS); |
| if (!context) |
| return -ENOMEM; |
| |
| context[len] = '\0'; |
| rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, |
| context, len); |
| } |
| if (rc < 0) { |
| kfree(context); |
| if (rc != -ENODATA) { |
| pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", |
| __func__, -rc, inode->i_sb->s_id, inode->i_ino); |
| return rc; |
| } |
| *sid = def_sid; |
| return 0; |
| } |
| |
| rc = security_context_to_sid_default(context, rc, sid, |
| def_sid, GFP_NOFS); |
| if (rc) { |
| char *dev = inode->i_sb->s_id; |
| unsigned long ino = inode->i_ino; |
| |
| if (rc == -EINVAL) { |
| pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n", |
| ino, dev, context); |
| } else { |
| pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", |
| __func__, context, -rc, dev, ino); |
| } |
| } |
| kfree(context); |
| return 0; |
| } |
| |
| /* The inode's security attributes must be initialized before first use. */ |
| static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) |
| { |
| struct superblock_security_struct *sbsec = NULL; |
| struct inode_security_struct *isec = selinux_inode(inode); |
| u32 task_sid, sid = 0; |
| u16 sclass; |
| struct dentry *dentry; |
| int rc = 0; |
| |
| if (isec->initialized == LABEL_INITIALIZED) |
| return 0; |
| |
| spin_lock(&isec->lock); |
| if (isec->initialized == LABEL_INITIALIZED) |
| goto out_unlock; |
| |
| if (isec->sclass == SECCLASS_FILE) |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| |
| sbsec = selinux_superblock(inode->i_sb); |
| if (!(sbsec->flags & SE_SBINITIALIZED)) { |
| /* Defer initialization until selinux_complete_init, |
| after the initial policy is loaded and the security |
| server is ready to handle calls. */ |
| spin_lock(&sbsec->isec_lock); |
| if (list_empty(&isec->list)) |
| list_add(&isec->list, &sbsec->isec_head); |
| spin_unlock(&sbsec->isec_lock); |
| goto out_unlock; |
| } |
| |
| sclass = isec->sclass; |
| task_sid = isec->task_sid; |
| sid = isec->sid; |
| isec->initialized = LABEL_PENDING; |
| spin_unlock(&isec->lock); |
| |
| switch (sbsec->behavior) { |
| /* |
| * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels |
| * via xattr when called from delayed_superblock_init(). |
| */ |
| case SECURITY_FS_USE_NATIVE: |
| case SECURITY_FS_USE_XATTR: |
| if (!(inode->i_opflags & IOP_XATTR)) { |
| sid = sbsec->def_sid; |
| break; |
| } |
| /* Need a dentry, since the xattr API requires one. |
| Life would be simpler if we could just pass the inode. */ |
| if (opt_dentry) { |
| /* Called from d_instantiate or d_splice_alias. */ |
| dentry = dget(opt_dentry); |
| } else { |
| /* |
| * Called from selinux_complete_init, try to find a dentry. |
| * Some filesystems really want a connected one, so try |
| * that first. We could split SECURITY_FS_USE_XATTR in |
| * two, depending upon that... |
| */ |
| dentry = d_find_alias(inode); |
| if (!dentry) |
| dentry = d_find_any_alias(inode); |
| } |
| if (!dentry) { |
| /* |
| * this is can be hit on boot when a file is accessed |
| * before the policy is loaded. When we load policy we |
| * may find inodes that have no dentry on the |
| * sbsec->isec_head list. No reason to complain as these |
| * will get fixed up the next time we go through |
| * inode_doinit with a dentry, before these inodes could |
| * be used again by userspace. |
| */ |
| goto out_invalid; |
| } |
| |
| rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, |
| &sid); |
| dput(dentry); |
| if (rc) |
| goto out; |
| break; |
| case SECURITY_FS_USE_TASK: |
| sid = task_sid; |
| break; |
| case SECURITY_FS_USE_TRANS: |
| /* Default to the fs SID. */ |
| sid = sbsec->sid; |
| |
| /* Try to obtain a transition SID. */ |
| rc = security_transition_sid(task_sid, sid, |
| sclass, NULL, &sid); |
| if (rc) |
| goto out; |
| break; |
| case SECURITY_FS_USE_MNTPOINT: |
| sid = sbsec->mntpoint_sid; |
| break; |
| default: |
| /* Default to the fs superblock SID. */ |
| sid = sbsec->sid; |
| |
| if ((sbsec->flags & SE_SBGENFS) && |
| (!S_ISLNK(inode->i_mode) || |
| selinux_policycap_genfs_seclabel_symlinks())) { |
| /* We must have a dentry to determine the label on |
| * procfs inodes */ |
| if (opt_dentry) { |
| /* Called from d_instantiate or |
| * d_splice_alias. */ |
| dentry = dget(opt_dentry); |
| } else { |
| /* Called from selinux_complete_init, try to |
| * find a dentry. Some filesystems really want |
| * a connected one, so try that first. |
| */ |
| dentry = d_find_alias(inode); |
| if (!dentry) |
| dentry = d_find_any_alias(inode); |
| } |
| /* |
| * This can be hit on boot when a file is accessed |
| * before the policy is loaded. When we load policy we |
| * may find inodes that have no dentry on the |
| * sbsec->isec_head list. No reason to complain as |
| * these will get fixed up the next time we go through |
| * inode_doinit() with a dentry, before these inodes |
| * could be used again by userspace. |
| */ |
| if (!dentry) |
| goto out_invalid; |
| rc = selinux_genfs_get_sid(dentry, sclass, |
| sbsec->flags, &sid); |
| if (rc) { |
| dput(dentry); |
| goto out; |
| } |
| |
| if ((sbsec->flags & SE_SBGENFS_XATTR) && |
| (inode->i_opflags & IOP_XATTR)) { |
| rc = inode_doinit_use_xattr(inode, dentry, |
| sid, &sid); |
| if (rc) { |
| dput(dentry); |
| goto out; |
| } |
| } |
| dput(dentry); |
| } |
| break; |
| } |
| |
| out: |
| spin_lock(&isec->lock); |
| if (isec->initialized == LABEL_PENDING) { |
| if (rc) { |
| isec->initialized = LABEL_INVALID; |
| goto out_unlock; |
| } |
| isec->initialized = LABEL_INITIALIZED; |
| isec->sid = sid; |
| } |
| |
| out_unlock: |
| spin_unlock(&isec->lock); |
| return rc; |
| |
| out_invalid: |
| spin_lock(&isec->lock); |
| if (isec->initialized == LABEL_PENDING) { |
| isec->initialized = LABEL_INVALID; |
| isec->sid = sid; |
| } |
| spin_unlock(&isec->lock); |
| return 0; |
| } |
| |
| /* Convert a Linux signal to an access vector. */ |
| static inline u32 signal_to_av(int sig) |
| { |
| u32 perm = 0; |
| |
| switch (sig) { |
| case SIGCHLD: |
| /* Commonly granted from child to parent. */ |
| perm = PROCESS__SIGCHLD; |
| break; |
| case SIGKILL: |
| /* Cannot be caught or ignored */ |
| perm = PROCESS__SIGKILL; |
| break; |
| case SIGSTOP: |
| /* Cannot be caught or ignored */ |
| perm = PROCESS__SIGSTOP; |
| break; |
| default: |
| /* All other signals. */ |
| perm = PROCESS__SIGNAL; |
| break; |
| } |
| |
| return perm; |
| } |
| |
| #if CAP_LAST_CAP > 63 |
| #error Fix SELinux to handle capabilities > 63. |
| #endif |
| |
| /* Check whether a task is allowed to use a capability. */ |
| static int cred_has_capability(const struct cred *cred, |
| int cap, unsigned int opts, bool initns) |
| { |
| struct common_audit_data ad; |
| struct av_decision avd; |
| u16 sclass; |
| u32 sid = cred_sid(cred); |
| u32 av = CAP_TO_MASK(cap); |
| int rc; |
| |
| ad.type = LSM_AUDIT_DATA_CAP; |
| ad.u.cap = cap; |
| |
| switch (CAP_TO_INDEX(cap)) { |
| case 0: |
| sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
| break; |
| case 1: |
| sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
| break; |
| default: |
| pr_err("SELinux: out of range capability %d\n", cap); |
| BUG(); |
| return -EINVAL; |
| } |
| |
| rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
| if (!(opts & CAP_OPT_NOAUDIT)) { |
| int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
| if (rc2) |
| return rc2; |
| } |
| return rc; |
| } |
| |
| /* Check whether a task has a particular permission to an inode. |
| The 'adp' parameter is optional and allows other audit |
| data to be passed (e.g. the dentry). */ |
| static int inode_has_perm(const struct cred *cred, |
| struct inode *inode, |
| u32 perms, |
| struct common_audit_data *adp) |
| { |
| struct inode_security_struct *isec; |
| u32 sid; |
| |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| |
| sid = cred_sid(cred); |
| isec = selinux_inode(inode); |
| |
| return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
| } |
| |
| /* Same as inode_has_perm, but pass explicit audit data containing |
| the dentry to help the auditing code to more easily generate the |
| pathname if needed. */ |
| static inline int dentry_has_perm(const struct cred *cred, |
| struct dentry *dentry, |
| u32 av) |
| { |
| struct inode *inode = d_backing_inode(dentry); |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = dentry; |
| __inode_security_revalidate(inode, dentry, true); |
| return inode_has_perm(cred, inode, av, &ad); |
| } |
| |
| /* Same as inode_has_perm, but pass explicit audit data containing |
| the path to help the auditing code to more easily generate the |
| pathname if needed. */ |
| static inline int path_has_perm(const struct cred *cred, |
| const struct path *path, |
| u32 av) |
| { |
| struct inode *inode = d_backing_inode(path->dentry); |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_PATH; |
| ad.u.path = *path; |
| __inode_security_revalidate(inode, path->dentry, true); |
| return inode_has_perm(cred, inode, av, &ad); |
| } |
| |
| /* Same as path_has_perm, but uses the inode from the file struct. */ |
| static inline int file_path_has_perm(const struct cred *cred, |
| struct file *file, |
| u32 av) |
| { |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_FILE; |
| ad.u.file = file; |
| return inode_has_perm(cred, file_inode(file), av, &ad); |
| } |
| |
| #ifdef CONFIG_BPF_SYSCALL |
| static int bpf_fd_pass(const struct file *file, u32 sid); |
| #endif |
| |
| /* Check whether a task can use an open file descriptor to |
| access an inode in a given way. Check access to the |
| descriptor itself, and then use dentry_has_perm to |
| check a particular permission to the file. |
| Access to the descriptor is implicitly granted if it |
| has the same SID as the process. If av is zero, then |
| access to the file is not checked, e.g. for cases |
| where only the descriptor is affected like seek. */ |
| static int file_has_perm(const struct cred *cred, |
| struct file *file, |
| u32 av) |
| { |
| struct file_security_struct *fsec = selinux_file(file); |
| struct inode *inode = file_inode(file); |
| struct common_audit_data ad; |
| u32 sid = cred_sid(cred); |
| int rc; |
| |
| ad.type = LSM_AUDIT_DATA_FILE; |
| ad.u.file = file; |
| |
| if (sid != fsec->sid) { |
| rc = avc_has_perm(sid, fsec->sid, |
| SECCLASS_FD, |
| FD__USE, |
| &ad); |
| if (rc) |
| goto out; |
| } |
| |
| #ifdef CONFIG_BPF_SYSCALL |
| rc = bpf_fd_pass(file, cred_sid(cred)); |
| if (rc) |
| return rc; |
| #endif |
| |
| /* av is zero if only checking access to the descriptor. */ |
| rc = 0; |
| if (av) |
| rc = inode_has_perm(cred, inode, av, &ad); |
| |
| out: |
| return rc; |
| } |
| |
| /* |
| * Determine the label for an inode that might be unioned. |
| */ |
| static int |
| selinux_determine_inode_label(const struct task_security_struct *tsec, |
| struct inode *dir, |
| const struct qstr *name, u16 tclass, |
| u32 *_new_isid) |
| { |
| const struct superblock_security_struct *sbsec = |
| selinux_superblock(dir->i_sb); |
| |
| if ((sbsec->flags & SE_SBINITIALIZED) && |
| (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { |
| *_new_isid = sbsec->mntpoint_sid; |
| } else if ((sbsec->flags & SBLABEL_MNT) && |
| tsec->create_sid) { |
| *_new_isid = tsec->create_sid; |
| } else { |
| const struct inode_security_struct *dsec = inode_security(dir); |
| return security_transition_sid(tsec->sid, |
| dsec->sid, tclass, |
| name, _new_isid); |
| } |
| |
| return 0; |
| } |
| |
| /* Check whether a task can create a file. */ |
| static int may_create(struct inode *dir, |
| struct dentry *dentry, |
| u16 tclass) |
| { |
| const struct task_security_struct *tsec = selinux_cred(current_cred()); |
| struct inode_security_struct *dsec; |
| struct superblock_security_struct *sbsec; |
| u32 sid, newsid; |
| struct common_audit_data ad; |
| int rc; |
| |
| dsec = inode_security(dir); |
| sbsec = selinux_superblock(dir->i_sb); |
| |
| sid = tsec->sid; |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = dentry; |
| |
| rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
| DIR__ADD_NAME | DIR__SEARCH, |
| &ad); |
| if (rc) |
| return rc; |
| |
| rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, |
| &newsid); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
| if (rc) |
| return rc; |
| |
| return avc_has_perm(newsid, sbsec->sid, |
| SECCLASS_FILESYSTEM, |
| FILESYSTEM__ASSOCIATE, &ad); |
| } |
| |
| #define MAY_LINK 0 |
| #define MAY_UNLINK 1 |
| #define MAY_RMDIR 2 |
| |
| /* Check whether a task can link, unlink, or rmdir a file/directory. */ |
| static int may_link(struct inode *dir, |
| struct dentry *dentry, |
| int kind) |
| |
| { |
| struct inode_security_struct *dsec, *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| u32 av; |
| int rc; |
| |
| dsec = inode_security(dir); |
| isec = backing_inode_security(dentry); |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = dentry; |
| |
| av = DIR__SEARCH; |
| av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); |
| rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
| if (rc) |
| return rc; |
| |
| switch (kind) { |
| case MAY_LINK: |
| av = FILE__LINK; |
| break; |
| case MAY_UNLINK: |
| av = FILE__UNLINK; |
| break; |
| case MAY_RMDIR: |
| av = DIR__RMDIR; |
| break; |
| default: |
| pr_warn("SELinux: %s: unrecognized kind %d\n", |
| __func__, kind); |
| return 0; |
| } |
| |
| rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
| return rc; |
| } |
| |
| static inline int may_rename(struct inode *old_dir, |
| struct dentry *old_dentry, |
| struct inode *new_dir, |
| struct dentry *new_dentry) |
| { |
| struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| u32 av; |
| int old_is_dir, new_is_dir; |
| int rc; |
| |
| old_dsec = inode_security(old_dir); |
| old_isec = backing_inode_security(old_dentry); |
| old_is_dir = d_is_dir(old_dentry); |
| new_dsec = inode_security(new_dir); |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| |
| ad.u.dentry = old_dentry; |
| rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
| DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
| if (rc) |
| return rc; |
| rc = avc_has_perm(sid, old_isec->sid, |
| old_isec->sclass, FILE__RENAME, &ad); |
| if (rc) |
| return rc; |
| if (old_is_dir && new_dir != old_dir) { |
| rc = avc_has_perm(sid, old_isec->sid, |
| old_isec->sclass, DIR__REPARENT, &ad); |
| if (rc) |
| return rc; |
| } |
| |
| ad.u.dentry = new_dentry; |
| av = DIR__ADD_NAME | DIR__SEARCH; |
| if (d_is_positive(new_dentry)) |
| av |= DIR__REMOVE_NAME; |
| rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
| if (rc) |
| return rc; |
| if (d_is_positive(new_dentry)) { |
| new_isec = backing_inode_security(new_dentry); |
| new_is_dir = d_is_dir(new_dentry); |
| rc = avc_has_perm(sid, new_isec->sid, |
| new_isec->sclass, |
| (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); |
| if (rc) |
| return rc; |
| } |
| |
| return 0; |
| } |
| |
| /* Check whether a task can perform a filesystem operation. */ |
| static int superblock_has_perm(const struct cred *cred, |
| const struct super_block *sb, |
| u32 perms, |
| struct common_audit_data *ad) |
| { |
| struct superblock_security_struct *sbsec; |
| u32 sid = cred_sid(cred); |
| |
| sbsec = selinux_superblock(sb); |
| return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
| } |
| |
| /* Convert a Linux mode and permission mask to an access vector. */ |
| static inline u32 file_mask_to_av(int mode, int mask) |
| { |
| u32 av = 0; |
| |
| if (!S_ISDIR(mode)) { |
| if (mask & MAY_EXEC) |
| av |= FILE__EXECUTE; |
| if (mask & MAY_READ) |
| av |= FILE__READ; |
| |
| if (mask & MAY_APPEND) |
| av |= FILE__APPEND; |
| else if (mask & MAY_WRITE) |
| av |= FILE__WRITE; |
| |
| } else { |
| if (mask & MAY_EXEC) |
| av |= DIR__SEARCH; |
| if (mask & MAY_WRITE) |
| av |= DIR__WRITE; |
| if (mask & MAY_READ) |
| av |= DIR__READ; |
| } |
| |
| return av; |
| } |
| |
| /* Convert a Linux file to an access vector. */ |
| static inline u32 file_to_av(const struct file *file) |
| { |
| u32 av = 0; |
| |
| if (file->f_mode & FMODE_READ) |
| av |= FILE__READ; |
| if (file->f_mode & FMODE_WRITE) { |
| if (file->f_flags & O_APPEND) |
| av |= FILE__APPEND; |
| else |
| av |= FILE__WRITE; |
| } |
| if (!av) { |
| /* |
| * Special file opened with flags 3 for ioctl-only use. |
| */ |
| av = FILE__IOCTL; |
| } |
| |
| return av; |
| } |
| |
| /* |
| * Convert a file to an access vector and include the correct |
| * open permission. |
| */ |
| static inline u32 open_file_to_av(struct file *file) |
| { |
| u32 av = file_to_av(file); |
| struct inode *inode = file_inode(file); |
| |
| if (selinux_policycap_openperm() && |
| inode->i_sb->s_magic != SOCKFS_MAGIC) |
| av |= FILE__OPEN; |
| |
| return av; |
| } |
| |
| /* Hook functions begin here. */ |
| |
| static int selinux_binder_set_context_mgr(const struct cred *mgr) |
| { |
| return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, |
| BINDER__SET_CONTEXT_MGR, NULL); |
| } |
| |
| static int selinux_binder_transaction(const struct cred *from, |
| const struct cred *to) |
| { |
| u32 mysid = current_sid(); |
| u32 fromsid = cred_sid(from); |
| u32 tosid = cred_sid(to); |
| int rc; |
| |
| if (mysid != fromsid) { |
| rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, |
| BINDER__IMPERSONATE, NULL); |
| if (rc) |
| return rc; |
| } |
| |
| return avc_has_perm(fromsid, tosid, |
| SECCLASS_BINDER, BINDER__CALL, NULL); |
| } |
| |
| static int selinux_binder_transfer_binder(const struct cred *from, |
| const struct cred *to) |
| { |
| return avc_has_perm(cred_sid(from), cred_sid(to), |
| SECCLASS_BINDER, BINDER__TRANSFER, |
| NULL); |
| } |
| |
| static int selinux_binder_transfer_file(const struct cred *from, |
| const struct cred *to, |
| const struct file *file) |
| { |
| u32 sid = cred_sid(to); |
| struct file_security_struct *fsec = selinux_file(file); |
| struct dentry *dentry = file->f_path.dentry; |
| struct inode_security_struct *isec; |
| struct common_audit_data ad; |
| int rc; |
| |
| ad.type = LSM_AUDIT_DATA_PATH; |
| ad.u.path = file->f_path; |
| |
| if (sid != fsec->sid) { |
| rc = avc_has_perm(sid, fsec->sid, |
| SECCLASS_FD, |
| FD__USE, |
| &ad); |
| if (rc) |
| return rc; |
| } |
| |
| #ifdef CONFIG_BPF_SYSCALL |
| rc = bpf_fd_pass(file, sid); |
| if (rc) |
| return rc; |
| #endif |
| |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| |
| isec = backing_inode_security(dentry); |
| return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), |
| &ad); |
| } |
| |
| static int selinux_ptrace_access_check(struct task_struct *child, |
| unsigned int mode) |
| { |
| u32 sid = current_sid(); |
| u32 csid = task_sid_obj(child); |
| |
| if (mode & PTRACE_MODE_READ) |
| return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, |
| NULL); |
| |
| return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, |
| NULL); |
| } |
| |
| static int selinux_ptrace_traceme(struct task_struct *parent) |
| { |
| return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), |
| SECCLASS_PROCESS, PROCESS__PTRACE, NULL); |
| } |
| |
| static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, |
| kernel_cap_t *inheritable, kernel_cap_t *permitted) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(target), |
| SECCLASS_PROCESS, PROCESS__GETCAP, NULL); |
| } |
| |
| static int selinux_capset(struct cred *new, const struct cred *old, |
| const kernel_cap_t *effective, |
| const kernel_cap_t *inheritable, |
| const kernel_cap_t *permitted) |
| { |
| return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, |
| PROCESS__SETCAP, NULL); |
| } |
| |
| /* |
| * (This comment used to live with the selinux_task_setuid hook, |
| * which was removed). |
| * |
| * Since setuid only affects the current process, and since the SELinux |
| * controls are not based on the Linux identity attributes, SELinux does not |
| * need to control this operation. However, SELinux does control the use of |
| * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. |
| */ |
| |
| static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
| int cap, unsigned int opts) |
| { |
| return cred_has_capability(cred, cap, opts, ns == &init_user_ns); |
| } |
| |
| static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) |
| { |
| const struct cred *cred = current_cred(); |
| int rc = 0; |
| |
| if (!sb) |
| return 0; |
| |
| switch (cmds) { |
| case Q_SYNC: |
| case Q_QUOTAON: |
| case Q_QUOTAOFF: |
| case Q_SETINFO: |
| case Q_SETQUOTA: |
| case Q_XQUOTAOFF: |
| case Q_XQUOTAON: |
| case Q_XSETQLIM: |
| rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
| break; |
| case Q_GETFMT: |
| case Q_GETINFO: |
| case Q_GETQUOTA: |
| case Q_XGETQUOTA: |
| case Q_XGETQSTAT: |
| case Q_XGETQSTATV: |
| case Q_XGETNEXTQUOTA: |
| rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
| break; |
| default: |
| rc = 0; /* let the kernel handle invalid cmds */ |
| break; |
| } |
| return rc; |
| } |
| |
| static int selinux_quota_on(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
| } |
| |
| static int selinux_syslog(int type) |
| { |
| switch (type) { |
| case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
| case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
| case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
| case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ |
| /* Set level of messages printed to console */ |
| case SYSLOG_ACTION_CONSOLE_LEVEL: |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
| NULL); |
| } |
| /* All other syslog types */ |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
| } |
| |
| /* |
| * Check that a process has enough memory to allocate a new virtual |
| * mapping. 0 means there is enough memory for the allocation to |
| * succeed and -ENOMEM implies there is not. |
| * |
| * Do not audit the selinux permission check, as this is applied to all |
| * processes that allocate mappings. |
| */ |
| static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
| { |
| int rc, cap_sys_admin = 0; |
| |
| rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
| CAP_OPT_NOAUDIT, true); |
| if (rc == 0) |
| cap_sys_admin = 1; |
| |
| return cap_sys_admin; |
| } |
| |
| /* binprm security operations */ |
| |
| static u32 ptrace_parent_sid(void) |
| { |
| u32 sid = 0; |
| struct task_struct *tracer; |
| |
| rcu_read_lock(); |
| tracer = ptrace_parent(current); |
| if (tracer) |
| sid = task_sid_obj(tracer); |
| rcu_read_unlock(); |
| |
| return sid; |
| } |
| |
| static int check_nnp_nosuid(const struct linux_binprm *bprm, |
| const struct task_security_struct *old_tsec, |
| const struct task_security_struct *new_tsec) |
| { |
| int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); |
| int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
| int rc; |
| u32 av; |
| |
| if (!nnp && !nosuid) |
| return 0; /* neither NNP nor nosuid */ |
| |
| if (new_tsec->sid == old_tsec->sid) |
| return 0; /* No change in credentials */ |
| |
| /* |
| * If the policy enables the nnp_nosuid_transition policy capability, |
| * then we permit transitions under NNP or nosuid if the |
| * policy allows the corresponding permission between |
| * the old and new contexts. |
| */ |
| if (selinux_policycap_nnp_nosuid_transition()) { |
| av = 0; |
| if (nnp) |
| av |= PROCESS2__NNP_TRANSITION; |
| if (nosuid) |
| av |= PROCESS2__NOSUID_TRANSITION; |
| rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
| SECCLASS_PROCESS2, av, NULL); |
| if (!rc) |
| return 0; |
| } |
| |
| /* |
| * We also permit NNP or nosuid transitions to bounded SIDs, |
| * i.e. SIDs that are guaranteed to only be allowed a subset |
| * of the permissions of the current SID. |
| */ |
| rc = security_bounded_transition(old_tsec->sid, |
| new_tsec->sid); |
| if (!rc) |
| return 0; |
| |
| /* |
| * On failure, preserve the errno values for NNP vs nosuid. |
| * NNP: Operation not permitted for caller. |
| * nosuid: Permission denied to file. |
| */ |
| if (nnp) |
| return -EPERM; |
| return -EACCES; |
| } |
| |
| static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) |
| { |
| const struct task_security_struct *old_tsec; |
| struct task_security_struct *new_tsec; |
| struct inode_security_struct *isec; |
| struct common_audit_data ad; |
| struct inode *inode = file_inode(bprm->file); |
| int rc; |
| |
| /* SELinux context only depends on initial program or script and not |
| * the script interpreter */ |
| |
| old_tsec = selinux_cred(current_cred()); |
| new_tsec = selinux_cred(bprm->cred); |
| isec = inode_security(inode); |
| |
| /* Default to the current task SID. */ |
| new_tsec->sid = old_tsec->sid; |
| new_tsec->osid = old_tsec->sid; |
| |
| /* Reset fs, key, and sock SIDs on execve. */ |
| new_tsec->create_sid = 0; |
| new_tsec->keycreate_sid = 0; |
| new_tsec->sockcreate_sid = 0; |
| |
| /* |
| * Before policy is loaded, label any task outside kernel space |
| * as SECINITSID_INIT, so that any userspace tasks surviving from |
| * early boot end up with a label different from SECINITSID_KERNEL |
| * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL). |
| */ |
| if (!selinux_initialized()) { |
| new_tsec->sid = SECINITSID_INIT; |
| /* also clear the exec_sid just in case */ |
| new_tsec->exec_sid = 0; |
| return 0; |
| } |
| |
| if (old_tsec->exec_sid) { |
| new_tsec->sid = old_tsec->exec_sid; |
| /* Reset exec SID on execve. */ |
| new_tsec->exec_sid = 0; |
| |
| /* Fail on NNP or nosuid if not an allowed transition. */ |
| rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); |
| if (rc) |
| return rc; |
| } else { |
| /* Check for a default transition on this program. */ |
| rc = security_transition_sid(old_tsec->sid, |
| isec->sid, SECCLASS_PROCESS, NULL, |
| &new_tsec->sid); |
| if (rc) |
| return rc; |
| |
| /* |
| * Fallback to old SID on NNP or nosuid if not an allowed |
| * transition. |
| */ |
| rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); |
| if (rc) |
| new_tsec->sid = old_tsec->sid; |
| } |
| |
| ad.type = LSM_AUDIT_DATA_FILE; |
| ad.u.file = bprm->file; |
| |
| if (new_tsec->sid == old_tsec->sid) { |
| rc = avc_has_perm(old_tsec->sid, isec->sid, |
| SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
| if (rc) |
| return rc; |
| } else { |
| /* Check permissions for the transition. */ |
| rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
| SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(new_tsec->sid, isec->sid, |
| SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
| if (rc) |
| return rc; |
| |
| /* Check for shared state */ |
| if (bprm->unsafe & LSM_UNSAFE_SHARE) { |
| rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
| SECCLASS_PROCESS, PROCESS__SHARE, |
| NULL); |
| if (rc) |
| return -EPERM; |
| } |
| |
| /* Make sure that anyone attempting to ptrace over a task that |
| * changes its SID has the appropriate permit */ |
| if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
| u32 ptsid = ptrace_parent_sid(); |
| if (ptsid != 0) { |
| rc = avc_has_perm(ptsid, new_tsec->sid, |
| SECCLASS_PROCESS, |
| PROCESS__PTRACE, NULL); |
| if (rc) |
| return -EPERM; |
| } |
| } |
| |
| /* Clear any possibly unsafe personality bits on exec: */ |
| bprm->per_clear |= PER_CLEAR_ON_SETID; |
| |
| /* Enable secure mode for SIDs transitions unless |
| the noatsecure permission is granted between |
| the two SIDs, i.e. ahp returns 0. */ |
| rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
| SECCLASS_PROCESS, PROCESS__NOATSECURE, |
| NULL); |
| bprm->secureexec |= !!rc; |
| } |
| |
| return 0; |
| } |
| |
| static int match_file(const void *p, struct file *file, unsigned fd) |
| { |
| return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; |
| } |
| |
| /* Derived from fs/exec.c:flush_old_files. */ |
| static inline void flush_unauthorized_files(const struct cred *cred, |
| struct files_struct *files) |
| { |
| struct file *file, *devnull = NULL; |
| struct tty_struct *tty; |
| int drop_tty = 0; |
| unsigned n; |
| |
| tty = get_current_tty(); |
| if (tty) { |
| spin_lock(&tty->files_lock); |
| if (!list_empty(&tty->tty_files)) { |
| struct tty_file_private *file_priv; |
| |
| /* Revalidate access to controlling tty. |
| Use file_path_has_perm on the tty path directly |
| rather than using file_has_perm, as this particular |
| open file may belong to another process and we are |
| only interested in the inode-based check here. */ |
| file_priv = list_first_entry(&tty->tty_files, |
| struct tty_file_private, list); |
| file = file_priv->file; |
| if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
| drop_tty = 1; |
| } |
| spin_unlock(&tty->files_lock); |
| tty_kref_put(tty); |
| } |
| /* Reset controlling tty. */ |
| if (drop_tty) |
| no_tty(); |
| |
| /* Revalidate access to inherited open files. */ |
| n = iterate_fd(files, 0, match_file, cred); |
| if (!n) /* none found? */ |
| return; |
| |
| devnull = dentry_open(&selinux_null, O_RDWR, cred); |
| if (IS_ERR(devnull)) |
| devnull = NULL; |
| /* replace all the matching ones with this */ |
| do { |
| replace_fd(n - 1, devnull, 0); |
| } while ((n = iterate_fd(files, n, match_file, cred)) != 0); |
| if (devnull) |
| fput(devnull); |
| } |
| |
| /* |
| * Prepare a process for imminent new credential changes due to exec |
| */ |
| static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) |
| { |
| struct task_security_struct *new_tsec; |
| struct rlimit *rlim, *initrlim; |
| int rc, i; |
| |
| new_tsec = selinux_cred(bprm->cred); |
| if (new_tsec->sid == new_tsec->osid) |
| return; |
| |
| /* Close files for which the new task SID is not authorized. */ |
| flush_unauthorized_files(bprm->cred, current->files); |
| |
| /* Always clear parent death signal on SID transitions. */ |
| current->pdeath_signal = 0; |
| |
| /* Check whether the new SID can inherit resource limits from the old |
| * SID. If not, reset all soft limits to the lower of the current |
| * task's hard limit and the init task's soft limit. |
| * |
| * Note that the setting of hard limits (even to lower them) can be |
| * controlled by the setrlimit check. The inclusion of the init task's |
| * soft limit into the computation is to avoid resetting soft limits |
| * higher than the default soft limit for cases where the default is |
| * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. |
| */ |
| rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, |
| PROCESS__RLIMITINH, NULL); |
| if (rc) { |
| /* protect against do_prlimit() */ |
| task_lock(current); |
| for (i = 0; i < RLIM_NLIMITS; i++) { |
| rlim = current->signal->rlim + i; |
| initrlim = init_task.signal->rlim + i; |
| rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); |
| } |
| task_unlock(current); |
| if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
| update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); |
| } |
| } |
| |
| /* |
| * Clean up the process immediately after the installation of new credentials |
| * due to exec |
| */ |
| static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) |
| { |
| const struct task_security_struct *tsec = selinux_cred(current_cred()); |
| u32 osid, sid; |
| int rc; |
| |
| osid = tsec->osid; |
| sid = tsec->sid; |
| |
| if (sid == osid) |
| return; |
| |
| /* Check whether the new SID can inherit signal state from the old SID. |
| * If not, clear itimers to avoid subsequent signal generation and |
| * flush and unblock signals. |
| * |
| * This must occur _after_ the task SID has been updated so that any |
| * kill done after the flush will be checked against the new SID. |
| */ |
| rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); |
| if (rc) { |
| clear_itimer(); |
| |
| spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); |
| if (!fatal_signal_pending(current)) { |
| flush_sigqueue(¤t->pending); |
| flush_sigqueue(¤t->signal->shared_pending); |
| flush_signal_handlers(current, 1); |
| sigemptyset(¤t->blocked); |
| recalc_sigpending(); |
| } |
| spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); |
| } |
| |
| /* Wake up the parent if it is waiting so that it can recheck |
| * wait permission to the new task SID. */ |
| read_lock(&tasklist_lock); |
| __wake_up_parent(current, unrcu_pointer(current->real_parent)); |
| read_unlock(&tasklist_lock); |
| } |
| |
| /* superblock security operations */ |
| |
| static int selinux_sb_alloc_security(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| |
| mutex_init(&sbsec->lock); |
| INIT_LIST_HEAD(&sbsec->isec_head); |
| spin_lock_init(&sbsec->isec_lock); |
| sbsec->sid = SECINITSID_UNLABELED; |
| sbsec->def_sid = SECINITSID_FILE; |
| sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
| |
| return 0; |
| } |
| |
| static inline int opt_len(const char *s) |
| { |
| bool open_quote = false; |
| int len; |
| char c; |
| |
| for (len = 0; (c = s[len]) != '\0'; len++) { |
| if (c == '"') |
| open_quote = !open_quote; |
| if (c == ',' && !open_quote) |
| break; |
| } |
| return len; |
| } |
| |
| static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
| { |
| char *from = options; |
| char *to = options; |
| bool first = true; |
| int rc; |
| |
| while (1) { |
| int len = opt_len(from); |
| int token; |
| char *arg = NULL; |
| |
| token = match_opt_prefix(from, len, &arg); |
| |
| if (token != Opt_error) { |
| char *p, *q; |
| |
| /* strip quotes */ |
| if (arg) { |
| for (p = q = arg; p < from + len; p++) { |
| char c = *p; |
| if (c != '"') |
| *q++ = c; |
| } |
| arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); |
| if (!arg) { |
| rc = -ENOMEM; |
| goto free_opt; |
| } |
| } |
| rc = selinux_add_opt(token, arg, mnt_opts); |
| kfree(arg); |
| arg = NULL; |
| if (unlikely(rc)) { |
| goto free_opt; |
| } |
| } else { |
| if (!first) { // copy with preceding comma |
| from--; |
| len++; |
| } |
| if (to != from) |
| memmove(to, from, len); |
| to += len; |
| first = false; |
| } |
| if (!from[len]) |
| break; |
| from += len + 1; |
| } |
| *to = '\0'; |
| return 0; |
| |
| free_opt: |
| if (*mnt_opts) { |
| selinux_free_mnt_opts(*mnt_opts); |
| *mnt_opts = NULL; |
| } |
| return rc; |
| } |
| |
| static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) |
| { |
| struct selinux_mnt_opts *opts = mnt_opts; |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| |
| /* |
| * Superblock not initialized (i.e. no options) - reject if any |
| * options specified, otherwise accept. |
| */ |
| if (!(sbsec->flags & SE_SBINITIALIZED)) |
| return opts ? 1 : 0; |
| |
| /* |
| * Superblock initialized and no options specified - reject if |
| * superblock has any options set, otherwise accept. |
| */ |
| if (!opts) |
| return (sbsec->flags & SE_MNTMASK) ? 1 : 0; |
| |
| if (opts->fscontext_sid) { |
| if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
| opts->fscontext_sid)) |
| return 1; |
| } |
| if (opts->context_sid) { |
| if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
| opts->context_sid)) |
| return 1; |
| } |
| if (opts->rootcontext_sid) { |
| struct inode_security_struct *root_isec; |
| |
| root_isec = backing_inode_security(sb->s_root); |
| if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
| opts->rootcontext_sid)) |
| return 1; |
| } |
| if (opts->defcontext_sid) { |
| if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
| opts->defcontext_sid)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
| { |
| struct selinux_mnt_opts *opts = mnt_opts; |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| |
| if (!(sbsec->flags & SE_SBINITIALIZED)) |
| return 0; |
| |
| if (!opts) |
| return 0; |
| |
| if (opts->fscontext_sid) { |
| if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
| opts->fscontext_sid)) |
| goto out_bad_option; |
| } |
| if (opts->context_sid) { |
| if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
| opts->context_sid)) |
| goto out_bad_option; |
| } |
| if (opts->rootcontext_sid) { |
| struct inode_security_struct *root_isec; |
| root_isec = backing_inode_security(sb->s_root); |
| if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
| opts->rootcontext_sid)) |
| goto out_bad_option; |
| } |
| if (opts->defcontext_sid) { |
| if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
| opts->defcontext_sid)) |
| goto out_bad_option; |
| } |
| return 0; |
| |
| out_bad_option: |
| pr_warn("SELinux: unable to change security options " |
| "during remount (dev %s, type=%s)\n", sb->s_id, |
| sb->s_type->name); |
| return -EINVAL; |
| } |
| |
| static int selinux_sb_kern_mount(const struct super_block *sb) |
| { |
| const struct cred *cred = current_cred(); |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = sb->s_root; |
| return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
| } |
| |
| static int selinux_sb_statfs(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = dentry->d_sb->s_root; |
| return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
| } |
| |
| static int selinux_mount(const char *dev_name, |
| const struct path *path, |
| const char *type, |
| unsigned long flags, |
| void *data) |
| { |
| const struct cred *cred = current_cred(); |
| |
| if (flags & MS_REMOUNT) |
| return superblock_has_perm(cred, path->dentry->d_sb, |
| FILESYSTEM__REMOUNT, NULL); |
| else |
| return path_has_perm(cred, path, FILE__MOUNTON); |
| } |
| |
| static int selinux_move_mount(const struct path *from_path, |
| const struct path *to_path) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return path_has_perm(cred, to_path, FILE__MOUNTON); |
| } |
| |
| static int selinux_umount(struct vfsmount *mnt, int flags) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return superblock_has_perm(cred, mnt->mnt_sb, |
| FILESYSTEM__UNMOUNT, NULL); |
| } |
| |
| static int selinux_fs_context_submount(struct fs_context *fc, |
| struct super_block *reference) |
| { |
| const struct superblock_security_struct *sbsec = selinux_superblock(reference); |
| struct selinux_mnt_opts *opts; |
| |
| /* |
| * Ensure that fc->security remains NULL when no options are set |
| * as expected by selinux_set_mnt_opts(). |
| */ |
| if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) |
| return 0; |
| |
| opts = kzalloc(sizeof(*opts), GFP_KERNEL); |
| if (!opts) |
| return -ENOMEM; |
| |
| if (sbsec->flags & FSCONTEXT_MNT) |
| opts->fscontext_sid = sbsec->sid; |
| if (sbsec->flags & CONTEXT_MNT) |
| opts->context_sid = sbsec->mntpoint_sid; |
| if (sbsec->flags & DEFCONTEXT_MNT) |
| opts->defcontext_sid = sbsec->def_sid; |
| fc->security = opts; |
| return 0; |
| } |
| |
| static int selinux_fs_context_dup(struct fs_context *fc, |
| struct fs_context *src_fc) |
| { |
| const struct selinux_mnt_opts *src = src_fc->security; |
| |
| if (!src) |
| return 0; |
| |
| fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); |
| return fc->security ? 0 : -ENOMEM; |
| } |
| |
| static const struct fs_parameter_spec selinux_fs_parameters[] = { |
| fsparam_string(CONTEXT_STR, Opt_context), |
| fsparam_string(DEFCONTEXT_STR, Opt_defcontext), |
| fsparam_string(FSCONTEXT_STR, Opt_fscontext), |
| fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), |
| fsparam_flag (SECLABEL_STR, Opt_seclabel), |
| {} |
| }; |
| |
| static int selinux_fs_context_parse_param(struct fs_context *fc, |
| struct fs_parameter *param) |
| { |
| struct fs_parse_result result; |
| int opt; |
| |
| opt = fs_parse(fc, selinux_fs_parameters, param, &result); |
| if (opt < 0) |
| return opt; |
| |
| return selinux_add_opt(opt, param->string, &fc->security); |
| } |
| |
| /* inode security operations */ |
| |
| static int selinux_inode_alloc_security(struct inode *inode) |
| { |
| struct inode_security_struct *isec = selinux_inode(inode); |
| u32 sid = current_sid(); |
| |
| spin_lock_init(&isec->lock); |
| INIT_LIST_HEAD(&isec->list); |
| isec->inode = inode; |
| isec->sid = SECINITSID_UNLABELED; |
| isec->sclass = SECCLASS_FILE; |
| isec->task_sid = sid; |
| isec->initialized = LABEL_INVALID; |
| |
| return 0; |
| } |
| |
| static void selinux_inode_free_security(struct inode *inode) |
| { |
| inode_free_security(inode); |
| } |
| |
| static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
| const struct qstr *name, |
| const char **xattr_name, void **ctx, |
| u32 *ctxlen) |
| { |
| u32 newsid; |
| int rc; |
| |
| rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
| d_inode(dentry->d_parent), name, |
| inode_mode_to_security_class(mode), |
| &newsid); |
| if (rc) |
| return rc; |
| |
| if (xattr_name) |
| *xattr_name = XATTR_NAME_SELINUX; |
| |
| return security_sid_to_context(newsid, (char **)ctx, |
| ctxlen); |
| } |
| |
| static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
| struct qstr *name, |
| const struct cred *old, |
| struct cred *new) |
| { |
| u32 newsid; |
| int rc; |
| struct task_security_struct *tsec; |
| |
| rc = selinux_determine_inode_label(selinux_cred(old), |
| d_inode(dentry->d_parent), name, |
| inode_mode_to_security_class(mode), |
| &newsid); |
| if (rc) |
| return rc; |
| |
| tsec = selinux_cred(new); |
| tsec->create_sid = newsid; |
| return 0; |
| } |
| |
| static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
| const struct qstr *qstr, |
| struct xattr *xattrs, int *xattr_count) |
| { |
| const struct task_security_struct *tsec = selinux_cred(current_cred()); |
| struct superblock_security_struct *sbsec; |
| struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); |
| u32 newsid, clen; |
| u16 newsclass; |
| int rc; |
| char *context; |
| |
| sbsec = selinux_superblock(dir->i_sb); |
| |
| newsid = tsec->create_sid; |
| newsclass = inode_mode_to_security_class(inode->i_mode); |
| rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid); |
| if (rc) |
| return rc; |
| |
| /* Possibly defer initialization to selinux_complete_init. */ |
| if (sbsec->flags & SE_SBINITIALIZED) { |
| struct inode_security_struct *isec = selinux_inode(inode); |
| isec->sclass = newsclass; |
| isec->sid = newsid; |
| isec->initialized = LABEL_INITIALIZED; |
| } |
| |
| if (!selinux_initialized() || |
| !(sbsec->flags & SBLABEL_MNT)) |
| return -EOPNOTSUPP; |
| |
| if (xattr) { |
| rc = security_sid_to_context_force(newsid, |
| &context, &clen); |
| if (rc) |
| return rc; |
| xattr->value = context; |
| xattr->value_len = clen; |
| xattr->name = XATTR_SELINUX_SUFFIX; |
| } |
| |
| return 0; |
| } |
| |
| static int selinux_inode_init_security_anon(struct inode *inode, |
| const struct qstr *name, |
| const struct inode *context_inode) |
| { |
| u32 sid = current_sid(); |
| struct common_audit_data ad; |
| struct inode_security_struct *isec; |
| int rc; |
| |
| if (unlikely(!selinux_initialized())) |
| return 0; |
| |
| isec = selinux_inode(inode); |
| |
| /* |
| * We only get here once per ephemeral inode. The inode has |
| * been initialized via inode_alloc_security but is otherwise |
| * untouched. |
| */ |
| |
| if (context_inode) { |
| struct inode_security_struct *context_isec = |
| selinux_inode(context_inode); |
| if (context_isec->initialized != LABEL_INITIALIZED) { |
| pr_err("SELinux: context_inode is not initialized\n"); |
| return -EACCES; |
| } |
| |
| isec->sclass = context_isec->sclass; |
| isec->sid = context_isec->sid; |
| } else { |
| isec->sclass = SECCLASS_ANON_INODE; |
| rc = security_transition_sid( |
| sid, sid, |
| isec->sclass, name, &isec->sid); |
| if (rc) |
| return rc; |
| } |
| |
| isec->initialized = LABEL_INITIALIZED; |
| /* |
| * Now that we've initialized security, check whether we're |
| * allowed to actually create this type of anonymous inode. |
| */ |
| |
| ad.type = LSM_AUDIT_DATA_ANONINODE; |
| ad.u.anonclass = name ? (const char *)name->name : "?"; |
| |
| return avc_has_perm(sid, |
| isec->sid, |
| isec->sclass, |
| FILE__CREATE, |
| &ad); |
| } |
| |
| static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
| { |
| return may_create(dir, dentry, SECCLASS_FILE); |
| } |
| |
| static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
| { |
| return may_link(dir, old_dentry, MAY_LINK); |
| } |
| |
| static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| return may_link(dir, dentry, MAY_UNLINK); |
| } |
| |
| static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) |
| { |
| return may_create(dir, dentry, SECCLASS_LNK_FILE); |
| } |
| |
| static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
| { |
| return may_create(dir, dentry, SECCLASS_DIR); |
| } |
| |
| static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| return may_link(dir, dentry, MAY_RMDIR); |
| } |
| |
| static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
| { |
| return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
| } |
| |
| static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
| struct inode *new_inode, struct dentry *new_dentry) |
| { |
| return may_rename(old_inode, old_dentry, new_inode, new_dentry); |
| } |
| |
| static int selinux_inode_readlink(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, dentry, FILE__READ); |
| } |
| |
| static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
| bool rcu) |
| { |
| struct common_audit_data ad; |
| struct inode_security_struct *isec; |
| u32 sid = current_sid(); |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = dentry; |
| isec = inode_security_rcu(inode, rcu); |
| if (IS_ERR(isec)) |
| return PTR_ERR(isec); |
| |
| return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); |
| } |
| |
| static noinline int audit_inode_permission(struct inode *inode, |
| u32 perms, u32 audited, u32 denied, |
| int result) |
| { |
| struct common_audit_data ad; |
| struct inode_security_struct *isec = selinux_inode(inode); |
| |
| ad.type = LSM_AUDIT_DATA_INODE; |
| ad.u.inode = inode; |
| |
| return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, |
| audited, denied, result, &ad); |
| } |
| |
| static int selinux_inode_permission(struct inode *inode, int mask) |
| { |
| u32 perms; |
| bool from_access; |
| bool no_block = mask & MAY_NOT_BLOCK; |
| struct inode_security_struct *isec; |
| u32 sid = current_sid(); |
| struct av_decision avd; |
| int rc, rc2; |
| u32 audited, denied; |
| |
| from_access = mask & MAY_ACCESS; |
| mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
| |
| /* No permission to check. Existence test. */ |
| if (!mask) |
| return 0; |
| |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| |
| perms = file_mask_to_av(inode->i_mode, mask); |
| |
| isec = inode_security_rcu(inode, no_block); |
| if (IS_ERR(isec)) |
| return PTR_ERR(isec); |
| |
| rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, |
| &avd); |
| audited = avc_audit_required(perms, &avd, rc, |
| from_access ? FILE__AUDIT_ACCESS : 0, |
| &denied); |
| if (likely(!audited)) |
| return rc; |
| |
| rc2 = audit_inode_permission(inode, perms, audited, denied, rc); |
| if (rc2) |
| return rc2; |
| return rc; |
| } |
| |
| static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, |
| struct iattr *iattr) |
| { |
| const struct cred *cred = current_cred(); |
| struct inode *inode = d_backing_inode(dentry); |
| unsigned int ia_valid = iattr->ia_valid; |
| __u32 av = FILE__WRITE; |
| |
| /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
| if (ia_valid & ATTR_FORCE) { |
| ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | |
| ATTR_FORCE); |
| if (!ia_valid) |
| return 0; |
| } |
| |
| if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
| ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) |
| return dentry_has_perm(cred, dentry, FILE__SETATTR); |
| |
| if (selinux_policycap_openperm() && |
| inode->i_sb->s_magic != SOCKFS_MAGIC && |
| (ia_valid & ATTR_SIZE) && |
| !(ia_valid & ATTR_FILE)) |
| av |= FILE__OPEN; |
| |
| return dentry_has_perm(cred, dentry, av); |
| } |
| |
| static int selinux_inode_getattr(const struct path *path) |
| { |
| return path_has_perm(current_cred(), path, FILE__GETATTR); |
| } |
| |
| static bool has_cap_mac_admin(bool audit) |
| { |
| const struct cred *cred = current_cred(); |
| unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
| |
| if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) |
| return false; |
| if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) |
| return false; |
| return true; |
| } |
| |
| /** |
| * selinux_inode_xattr_skipcap - Skip the xattr capability checks? |
| * @name: name of the xattr |
| * |
| * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs |
| * named @name; the LSM layer should avoid enforcing any traditional |
| * capability based access controls on this xattr. Returns 0 to indicate that |
| * SELinux does not "own" the access control rights to xattrs named @name and is |
| * deferring to the LSM layer for further access controls, including capability |
| * based controls. |
| */ |
| static int selinux_inode_xattr_skipcap(const char *name) |
| { |
| /* require capability check if not a selinux xattr */ |
| return !strcmp(name, XATTR_NAME_SELINUX); |
| } |
| |
| static int selinux_inode_setxattr(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| struct inode *inode = d_backing_inode(dentry); |
| struct inode_security_struct *isec; |
| struct superblock_security_struct *sbsec; |
| struct common_audit_data ad; |
| u32 newsid, sid = current_sid(); |
| int rc = 0; |
| |
| /* if not a selinux xattr, only check the ordinary setattr perm */ |
| if (strcmp(name, XATTR_NAME_SELINUX)) |
| return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
| |
| if (!selinux_initialized()) |
| return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); |
| |
| sbsec = selinux_superblock(inode->i_sb); |
| if (!(sbsec->flags & SBLABEL_MNT)) |
| return -EOPNOTSUPP; |
| |
| if (!inode_owner_or_capable(idmap, inode)) |
| return -EPERM; |
| |
| ad.type = LSM_AUDIT_DATA_DENTRY; |
| ad.u.dentry = dentry; |
| |
| isec = backing_inode_security(dentry); |
| rc = avc_has_perm(sid, isec->sid, isec->sclass, |
| FILE__RELABELFROM, &ad); |
| if (rc) |
| return rc; |
| |
| rc = security_context_to_sid(value, size, &newsid, |
| GFP_KERNEL); |
| if (rc == -EINVAL) { |
| if (!has_cap_mac_admin(true)) { |
| struct audit_buffer *ab; |
| size_t audit_size; |
| |
| /* We strip a nul only if it is at the end, otherwise the |
| * context contains a nul and we should audit that */ |
| if (value) { |
| const char *str = value; |
| |
| if (str[size - 1] == '\0') |
| audit_size = size - 1; |
| else |
| audit_size = size; |
| } else { |
| audit_size = 0; |
| } |
| ab = audit_log_start(audit_context(), |
| GFP_ATOMIC, AUDIT_SELINUX_ERR); |
| if (!ab) |
| return rc; |
| audit_log_format(ab, "op=setxattr invalid_context="); |
| audit_log_n_untrustedstring(ab, value, audit_size); |
| audit_log_end(ab); |
| |
| return rc; |
| } |
| rc = security_context_to_sid_force(value, |
| size, &newsid); |
| } |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(sid, newsid, isec->sclass, |
| FILE__RELABELTO, &ad); |
| if (rc) |
| return rc; |
| |
| rc = security_validate_transition(isec->sid, newsid, |
| sid, isec->sclass); |
| if (rc) |
| return rc; |
| |
| return avc_has_perm(newsid, |
| sbsec->sid, |
| SECCLASS_FILESYSTEM, |
| FILESYSTEM__ASSOCIATE, |
| &ad); |
| } |
| |
| static int selinux_inode_set_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name, |
| struct posix_acl *kacl) |
| { |
| return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
| } |
| |
| static int selinux_inode_get_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name) |
| { |
| return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); |
| } |
| |
| static int selinux_inode_remove_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name) |
| { |
| return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
| } |
| |
| static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
| const void *value, size_t size, |
| int flags) |
| { |
| struct inode *inode = d_backing_inode(dentry); |
| struct inode_security_struct *isec; |
| u32 newsid; |
| int rc; |
| |
| if (strcmp(name, XATTR_NAME_SELINUX)) { |
| /* Not an attribute we recognize, so nothing to do. */ |
| return; |
| } |
| |
| if (!selinux_initialized()) { |
| /* If we haven't even been initialized, then we can't validate |
| * against a policy, so leave the label as invalid. It may |
| * resolve to a valid label on the next revalidation try if |
| * we've since initialized. |
| */ |
| return; |
| } |
| |
| rc = security_context_to_sid_force(value, size, |
| &newsid); |
| if (rc) { |
| pr_err("SELinux: unable to map context to SID" |
| "for (%s, %lu), rc=%d\n", |
| inode->i_sb->s_id, inode->i_ino, -rc); |
| return; |
| } |
| |
| isec = backing_inode_security(dentry); |
| spin_lock(&isec->lock); |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| isec->sid = newsid; |
| isec->initialized = LABEL_INITIALIZED; |
| spin_unlock(&isec->lock); |
| } |
| |
| static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, dentry, FILE__GETATTR); |
| } |
| |
| static int selinux_inode_listxattr(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, dentry, FILE__GETATTR); |
| } |
| |
| static int selinux_inode_removexattr(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *name) |
| { |
| /* if not a selinux xattr, only check the ordinary setattr perm */ |
| if (strcmp(name, XATTR_NAME_SELINUX)) |
| return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| /* No one is allowed to remove a SELinux security label. |
| You can change the label, but all data must be labeled. */ |
| return -EACCES; |
| } |
| |
| static int selinux_path_notify(const struct path *path, u64 mask, |
| unsigned int obj_type) |
| { |
| int ret; |
| u32 perm; |
| |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_PATH; |
| ad.u.path = *path; |
| |
| /* |
| * Set permission needed based on the type of mark being set. |
| * Performs an additional check for sb watches. |
| */ |
| switch (obj_type) { |
| case FSNOTIFY_OBJ_TYPE_VFSMOUNT: |
| perm = FILE__WATCH_MOUNT; |
| break; |
| case FSNOTIFY_OBJ_TYPE_SB: |
| perm = FILE__WATCH_SB; |
| ret = superblock_has_perm(current_cred(), path->dentry->d_sb, |
| FILESYSTEM__WATCH, &ad); |
| if (ret) |
| return ret; |
| break; |
| case FSNOTIFY_OBJ_TYPE_INODE: |
| perm = FILE__WATCH; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| /* blocking watches require the file:watch_with_perm permission */ |
| if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) |
| perm |= FILE__WATCH_WITH_PERM; |
| |
| /* watches on read-like events need the file:watch_reads permission */ |
| if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) |
| perm |= FILE__WATCH_READS; |
| |
| return path_has_perm(current_cred(), path, perm); |
| } |
| |
| /* |
| * Copy the inode security context value to the user. |
| * |
| * Permission check is handled by selinux_inode_getxattr hook. |
| */ |
| static int selinux_inode_getsecurity(struct mnt_idmap *idmap, |
| struct inode *inode, const char *name, |
| void **buffer, bool alloc) |
| { |
| u32 size; |
| int error; |
| char *context = NULL; |
| struct inode_security_struct *isec; |
| |
| /* |
| * If we're not initialized yet, then we can't validate contexts, so |
| * just let vfs_getxattr fall back to using the on-disk xattr. |
| */ |
| if (!selinux_initialized() || |
| strcmp(name, XATTR_SELINUX_SUFFIX)) |
| return -EOPNOTSUPP; |
| |
| /* |
| * If the caller has CAP_MAC_ADMIN, then get the raw context |
| * value even if it is not defined by current policy; otherwise, |
| * use the in-core value under current policy. |
| * Use the non-auditing forms of the permission checks since |
| * getxattr may be called by unprivileged processes commonly |
| * and lack of permission just means that we fall back to the |
| * in-core context value, not a denial. |
| */ |
| isec = inode_security(inode); |
| if (has_cap_mac_admin(false)) |
| error = security_sid_to_context_force(isec->sid, &context, |
| &size); |
| else |
| error = security_sid_to_context(isec->sid, |
| &context, &size); |
| if (error) |
| return error; |
| error = size; |
| if (alloc) { |
| *buffer = context; |
| goto out_nofree; |
| } |
| kfree(context); |
| out_nofree: |
| return error; |
| } |
| |
| static int selinux_inode_setsecurity(struct inode *inode, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| struct inode_security_struct *isec = inode_security_novalidate(inode); |
| struct superblock_security_struct *sbsec; |
| u32 newsid; |
| int rc; |
| |
| if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
| return -EOPNOTSUPP; |
| |
| sbsec = selinux_superblock(inode->i_sb); |
| if (!(sbsec->flags & SBLABEL_MNT)) |
| return -EOPNOTSUPP; |
| |
| if (!value || !size) |
| return -EACCES; |
| |
| rc = security_context_to_sid(value, size, &newsid, |
| GFP_KERNEL); |
| if (rc) |
| return rc; |
| |
| spin_lock(&isec->lock); |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| isec->sid = newsid; |
| isec->initialized = LABEL_INITIALIZED; |
| spin_unlock(&isec->lock); |
| return 0; |
| } |
| |
| static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) |
| { |
| const int len = sizeof(XATTR_NAME_SELINUX); |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| if (buffer && len <= buffer_size) |
| memcpy(buffer, XATTR_NAME_SELINUX, len); |
| return len; |
| } |
| |
| static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
| { |
| struct inode_security_struct *isec = inode_security_novalidate(inode); |
| *secid = isec->sid; |
| } |
| |
| static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
| { |
| u32 sid; |
| struct task_security_struct *tsec; |
| struct cred *new_creds = *new; |
| |
| if (new_creds == NULL) { |
| new_creds = prepare_creds(); |
| if (!new_creds) |
| return -ENOMEM; |
| } |
| |
| tsec = selinux_cred(new_creds); |
| /* Get label from overlay inode and set it in create_sid */ |
| selinux_inode_getsecid(d_inode(src), &sid); |
| tsec->create_sid = sid; |
| *new = new_creds; |
| return 0; |
| } |
| |
| static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name) |
| { |
| /* The copy_up hook above sets the initial context on an inode, but we |
| * don't then want to overwrite it by blindly copying all the lower |
| * xattrs up. Instead, filter out SELinux-related xattrs following |
| * policy load. |
| */ |
| if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0) |
| return 1; /* Discard */ |
| /* |
| * Any other attribute apart from SELINUX is not claimed, supported |
| * by selinux. |
| */ |
| return -EOPNOTSUPP; |
| } |
| |
| /* kernfs node operations */ |
| |
| static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
| struct kernfs_node *kn) |
| { |
| const struct task_security_struct *tsec = selinux_cred(current_cred()); |
| u32 parent_sid, newsid, clen; |
| int rc; |
| char *context; |
| |
| rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); |
| if (rc == -ENODATA) |
| return 0; |
| else if (rc < 0) |
| return rc; |
| |
| clen = (u32)rc; |
| context = kmalloc(clen, GFP_KERNEL); |
| if (!context) |
| return -ENOMEM; |
| |
| rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); |
| if (rc < 0) { |
| kfree(context); |
| return rc; |
| } |
| |
| rc = security_context_to_sid(context, clen, &parent_sid, |
| GFP_KERNEL); |
| kfree(context); |
| if (rc) |
| return rc; |
| |
| if (tsec->create_sid) { |
| newsid = tsec->create_sid; |
| } else { |
| u16 secclass = inode_mode_to_security_class(kn->mode); |
| struct qstr q; |
| |
| q.name = kn->name; |
| q.hash_len = hashlen_string(kn_dir, kn->name); |
| |
| rc = security_transition_sid(tsec->sid, |
| parent_sid, secclass, &q, |
| &newsid); |
| if (rc) |
| return rc; |
| } |
| |
| rc = security_sid_to_context_force(newsid, |
| &context, &clen); |
| if (rc) |
| return rc; |
| |
| rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, |
| XATTR_CREATE); |
| kfree(context); |
| return rc; |
| } |
| |
| |
| /* file security operations */ |
| |
| static int selinux_revalidate_file_permission(struct file *file, int mask) |
| { |
| const struct cred *cred = current_cred(); |
| struct inode *inode = file_inode(file); |
| |
| /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
| if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) |
| mask |= MAY_APPEND; |
| |
| return file_has_perm(cred, file, |
| file_mask_to_av(inode->i_mode, mask)); |
| } |
| |
| static int selinux_file_permission(struct file *file, int mask) |
| { |
| struct inode *inode = file_inode(file); |
| struct file_security_struct *fsec = selinux_file(file); |
| struct inode_security_struct *isec; |
| u32 sid = current_sid(); |
| |
| if (!mask) |
| /* No permission to check. Existence test. */ |
| return 0; |
| |
| isec = inode_security(inode); |
| if (sid == fsec->sid && fsec->isid == isec->sid && |
| fsec->pseqno == avc_policy_seqno()) |
| /* No change since file_open check. */ |
| return 0; |
| |
| return selinux_revalidate_file_permission(file, mask); |
| } |
| |
| static int selinux_file_alloc_security(struct file *file) |
| { |
| struct file_security_struct *fsec = selinux_file(file); |
| u32 sid = current_sid(); |
| |
| fsec->sid = sid; |
| fsec->fown_sid = sid; |
| |
| return 0; |
| } |
| |
| /* |
| * Check whether a task has the ioctl permission and cmd |
| * operation to an inode. |
| */ |
| static int ioctl_has_perm(const struct cred *cred, struct file *file, |
| u32 requested, u16 cmd) |
| { |
| struct common_audit_data ad; |
| struct file_security_struct *fsec = selinux_file(file); |
| struct inode *inode = file_inode(file); |
| struct inode_security_struct *isec; |
| struct lsm_ioctlop_audit ioctl; |
| u32 ssid = cred_sid(cred); |
| int rc; |
| u8 driver = cmd >> 8; |
| u8 xperm = cmd & 0xff; |
| |
| ad.type = LSM_AUDIT_DATA_IOCTL_OP; |
| ad.u.op = &ioctl; |
| ad.u.op->cmd = cmd; |
| ad.u.op->path = file->f_path; |
| |
| if (ssid != fsec->sid) { |
| rc = avc_has_perm(ssid, fsec->sid, |
| SECCLASS_FD, |
| FD__USE, |
| &ad); |
| if (rc) |
| goto out; |
| } |
| |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| |
| isec = inode_security(inode); |
| rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, |
| requested, driver, xperm, &ad); |
| out: |
| return rc; |
| } |
| |
| static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| const struct cred *cred = current_cred(); |
| int error = 0; |
| |
| switch (cmd) { |
| case FIONREAD: |
| case FIBMAP: |
| case FIGETBSZ: |
| case FS_IOC_GETFLAGS: |
| case FS_IOC_GETVERSION: |
| error = file_has_perm(cred, file, FILE__GETATTR); |
| break; |
| |
| case FS_IOC_SETFLAGS: |
| case FS_IOC_SETVERSION: |
| error = file_has_perm(cred, file, FILE__SETATTR); |
| break; |
| |
| /* sys_ioctl() checks */ |
| case FIONBIO: |
| case FIOASYNC: |
| error = file_has_perm(cred, file, 0); |
| break; |
| |
| case KDSKBENT: |
| case KDSKBSENT: |
| error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
| CAP_OPT_NONE, true); |
| break; |
| |
| case FIOCLEX: |
| case FIONCLEX: |
| if (!selinux_policycap_ioctl_skip_cloexec()) |
| error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
| break; |
| |
| /* default case assumes that the command will go |
| * to the file's ioctl() function. |
| */ |
| default: |
| error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
| } |
| return error; |
| } |
| |
| static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| /* |
| * If we are in a 64-bit kernel running 32-bit userspace, we need to |
| * make sure we don't compare 32-bit flags to 64-bit flags. |
| */ |
| switch (cmd) { |
| case FS_IOC32_GETFLAGS: |
| cmd = FS_IOC_GETFLAGS; |
| break; |
| case FS_IOC32_SETFLAGS: |
| cmd = FS_IOC_SETFLAGS; |
| break; |
| case FS_IOC32_GETVERSION: |
| cmd = FS_IOC_GETVERSION; |
| break; |
| case FS_IOC32_SETVERSION: |
| cmd = FS_IOC_SETVERSION; |
| break; |
| default: |
| break; |
| } |
| |
| return selinux_file_ioctl(file, cmd, arg); |
| } |
| |
| static int default_noexec __ro_after_init; |
| |
| static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
| { |
| const struct cred *cred = current_cred(); |
| u32 sid = cred_sid(cred); |
| int rc = 0; |
| |
| if (default_noexec && |
| (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
| (!shared && (prot & PROT_WRITE)))) { |
| /* |
| * We are making executable an anonymous mapping or a |
| * private file mapping that will also be writable. |
| * This has an additional check. |
| */ |
| rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
| PROCESS__EXECMEM, NULL); |
| if (rc) |
| goto error; |
| } |
| |
| if (file) { |
| /* read access is always possible with a mapping */ |
| u32 av = FILE__READ; |
| |
| /* write access only matters if the mapping is shared */ |
| if (shared && (prot & PROT_WRITE)) |
| av |= FILE__WRITE; |
| |
| if (prot & PROT_EXEC) |
| av |= FILE__EXECUTE; |
| |
| return file_has_perm(cred, file, av); |
| } |
| |
| error: |
| return rc; |
| } |
| |
| static int selinux_mmap_addr(unsigned long addr) |
| { |
| int rc = 0; |
| |
| if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
| u32 sid = current_sid(); |
| rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
| MEMPROTECT__MMAP_ZERO, NULL); |
| } |
| |
| return rc; |
| } |
| |
| static int selinux_mmap_file(struct file *file, |
| unsigned long reqprot __always_unused, |
| unsigned long prot, unsigned long flags) |
| { |
| struct common_audit_data ad; |
| int rc; |
| |
| if (file) { |
| ad.type = LSM_AUDIT_DATA_FILE; |
| ad.u.file = file; |
| rc = inode_has_perm(current_cred(), file_inode(file), |
| FILE__MAP, &ad); |
| if (rc) |
| return rc; |
| } |
| |
| return file_map_prot_check(file, prot, |
| (flags & MAP_TYPE) == MAP_SHARED); |
| } |
| |
| static int selinux_file_mprotect(struct vm_area_struct *vma, |
| unsigned long reqprot __always_unused, |
| unsigned long prot) |
| { |
| const struct cred *cred = current_cred(); |
| u32 sid = cred_sid(cred); |
| |
| if (default_noexec && |
| (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
| int rc = 0; |
| if (vma_is_initial_heap(vma)) { |
| rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
| PROCESS__EXECHEAP, NULL); |
| } else if (!vma->vm_file && (vma_is_initial_stack(vma) || |
| vma_is_stack_for_current(vma))) { |
| rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
| PROCESS__EXECSTACK, NULL); |
| } else if (vma->vm_file && vma->anon_vma) { |
| /* |
| * We are making executable a file mapping that has |
| * had some COW done. Since pages might have been |
| * written, check ability to execute the possibly |
| * modified content. This typically should only |
| * occur for text relocations. |
| */ |
| rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
| } |
| if (rc) |
| return rc; |
| } |
| |
| return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); |
| } |
| |
| static int selinux_file_lock(struct file *file, unsigned int cmd) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return file_has_perm(cred, file, FILE__LOCK); |
| } |
| |
| static int selinux_file_fcntl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| const struct cred *cred = current_cred(); |
| int err = 0; |
| |
| switch (cmd) { |
| case F_SETFL: |
| if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { |
| err = file_has_perm(cred, file, FILE__WRITE); |
| break; |
| } |
| fallthrough; |
| case F_SETOWN: |
| case F_SETSIG: |
| case F_GETFL: |
| case F_GETOWN: |
| case F_GETSIG: |
| case F_GETOWNER_UIDS: |
| /* Just check FD__USE permission */ |
| err = file_has_perm(cred, file, 0); |
| break; |
| case F_GETLK: |
| case F_SETLK: |
| case F_SETLKW: |
| case F_OFD_GETLK: |
| case F_OFD_SETLK: |
| case F_OFD_SETLKW: |
| #if BITS_PER_LONG == 32 |
| case F_GETLK64: |
| case F_SETLK64: |
| case F_SETLKW64: |
| #endif |
| err = file_has_perm(cred, file, FILE__LOCK); |
| break; |
| } |
| |
| return err; |
| } |
| |
| static void selinux_file_set_fowner(struct file *file) |
| { |
| struct file_security_struct *fsec; |
| |
| fsec = selinux_file(file); |
| fsec->fown_sid = current_sid(); |
| } |
| |
| static int selinux_file_send_sigiotask(struct task_struct *tsk, |
| struct fown_struct *fown, int signum) |
| { |
| struct file *file; |
| u32 sid = task_sid_obj(tsk); |
| u32 perm; |
| struct file_security_struct *fsec; |
| |
| /* struct fown_struct is never outside the context of a struct file */ |
| file = container_of(fown, struct file, f_owner); |
| |
| fsec = selinux_file(file); |
| |
| if (!signum) |
| perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ |
| else |
| perm = signal_to_av(signum); |
| |
| return avc_has_perm(fsec->fown_sid, sid, |
| SECCLASS_PROCESS, perm, NULL); |
| } |
| |
| static int selinux_file_receive(struct file *file) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return file_has_perm(cred, file, file_to_av(file)); |
| } |
| |
| static int selinux_file_open(struct file *file) |
| { |
| struct file_security_struct *fsec; |
| struct inode_security_struct *isec; |
| |
| fsec = selinux_file(file); |
| isec = inode_security(file_inode(file)); |
| /* |
| * Save inode label and policy sequence number |
| * at open-time so that selinux_file_permission |
| * can determine whether revalidation is necessary. |
| * Task label is already saved in the file security |
| * struct as its SID. |
| */ |
| fsec->isid = isec->sid; |
| fsec->pseqno = avc_policy_seqno(); |
| /* |
| * Since the inode label or policy seqno may have changed |
| * between the selinux_inode_permission check and the saving |
| * of state above, recheck that access is still permitted. |
| * Otherwise, access might never be revalidated against the |
| * new inode label or new policy. |
| * This check is not redundant - do not remove. |
| */ |
| return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); |
| } |
| |
| /* task security operations */ |
| |
| static int selinux_task_alloc(struct task_struct *task, |
| unsigned long clone_flags) |
| { |
| u32 sid = current_sid(); |
| |
| return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); |
| } |
| |
| /* |
| * prepare a new set of credentials for modification |
| */ |
| static int selinux_cred_prepare(struct cred *new, const struct cred *old, |
| gfp_t gfp) |
| { |
| const struct task_security_struct *old_tsec = selinux_cred(old); |
| struct task_security_struct *tsec = selinux_cred(new); |
| |
| *tsec = *old_tsec; |
| return 0; |
| } |
| |
| /* |
| * transfer the SELinux data to a blank set of creds |
| */ |
| static void selinux_cred_transfer(struct cred *new, const struct cred *old) |
| { |
| const struct task_security_struct *old_tsec = selinux_cred(old); |
| struct task_security_struct *tsec = selinux_cred(new); |
| |
| *tsec = *old_tsec; |
| } |
| |
| static void selinux_cred_getsecid(const struct cred *c, u32 *secid) |
| { |
| *secid = cred_sid(c); |
| } |
| |
| /* |
| * set the security data for a kernel service |
| * - all the creation contexts are set to unlabelled |
| */ |
| static int selinux_kernel_act_as(struct cred *new, u32 secid) |
| { |
| struct task_security_struct *tsec = selinux_cred(new); |
| u32 sid = current_sid(); |
| int ret; |
| |
| ret = avc_has_perm(sid, secid, |
| SECCLASS_KERNEL_SERVICE, |
| KERNEL_SERVICE__USE_AS_OVERRIDE, |
| NULL); |
| if (ret == 0) { |
| tsec->sid = secid; |
| tsec->create_sid = 0; |
| tsec->keycreate_sid = 0; |
| tsec->sockcreate_sid = 0; |
| } |
| return ret; |
| } |
| |
| /* |
| * set the file creation context in a security record to the same as the |
| * objective context of the specified inode |
| */ |
| static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) |
| { |
| struct inode_security_struct *isec = inode_security(inode); |
| struct task_security_struct *tsec = selinux_cred(new); |
| u32 sid = current_sid(); |
| int ret; |
| |
| ret = avc_has_perm(sid, isec->sid, |
| SECCLASS_KERNEL_SERVICE, |
| KERNEL_SERVICE__CREATE_FILES_AS, |
| NULL); |
| |
| if (ret == 0) |
| tsec->create_sid = isec->sid; |
| return ret; |
| } |
| |
| static int selinux_kernel_module_request(char *kmod_name) |
| { |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_KMOD; |
| ad.u.kmod_name = kmod_name; |
| |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, |
| SYSTEM__MODULE_REQUEST, &ad); |
| } |
| |
| static int selinux_kernel_module_from_file(struct file *file) |
| { |
| struct common_audit_data ad; |
| struct inode_security_struct *isec; |
| struct file_security_struct *fsec; |
| u32 sid = current_sid(); |
| int rc; |
| |
| /* init_module */ |
| if (file == NULL) |
| return avc_has_perm(sid, sid, SECCLASS_SYSTEM, |
| SYSTEM__MODULE_LOAD, NULL); |
| |
| /* finit_module */ |
| |
| ad.type = LSM_AUDIT_DATA_FILE; |
| ad.u.file = file; |
| |
| fsec = selinux_file(file); |
| if (sid != fsec->sid) { |
| rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); |
| if (rc) |
| return rc; |
| } |
| |
| isec = inode_security(file_inode(file)); |
| return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, |
| SYSTEM__MODULE_LOAD, &ad); |
| } |
| |
| static int selinux_kernel_read_file(struct file *file, |
| enum kernel_read_file_id id, |
| bool contents) |
| { |
| int rc = 0; |
| |
| switch (id) { |
| case READING_MODULE: |
| rc = selinux_kernel_module_from_file(contents ? file : NULL); |
| break; |
| default: |
| break; |
| } |
| |
| return rc; |
| } |
| |
| static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) |
| { |
| int rc = 0; |
| |
| switch (id) { |
| case LOADING_MODULE: |
| rc = selinux_kernel_module_from_file(NULL); |
| break; |
| default: |
| break; |
| } |
| |
| return rc; |
| } |
| |
| static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__SETPGID, NULL); |
| } |
| |
| static int selinux_task_getpgid(struct task_struct *p) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__GETPGID, NULL); |
| } |
| |
| static int selinux_task_getsid(struct task_struct *p) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__GETSESSION, NULL); |
| } |
| |
| static void selinux_current_getsecid_subj(u32 *secid) |
| { |
| *secid = current_sid(); |
| } |
| |
| static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) |
| { |
| *secid = task_sid_obj(p); |
| } |
| |
| static int selinux_task_setnice(struct task_struct *p, int nice) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__SETSCHED, NULL); |
| } |
| |
| static int selinux_task_setioprio(struct task_struct *p, int ioprio) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__SETSCHED, NULL); |
| } |
| |
| static int selinux_task_getioprio(struct task_struct *p) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__GETSCHED, NULL); |
| } |
| |
| static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, |
| unsigned int flags) |
| { |
| u32 av = 0; |
| |
| if (!flags) |
| return 0; |
| if (flags & LSM_PRLIMIT_WRITE) |
| av |= PROCESS__SETRLIMIT; |
| if (flags & LSM_PRLIMIT_READ) |
| av |= PROCESS__GETRLIMIT; |
| return avc_has_perm(cred_sid(cred), cred_sid(tcred), |
| SECCLASS_PROCESS, av, NULL); |
| } |
| |
| static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, |
| struct rlimit *new_rlim) |
| { |
| struct rlimit *old_rlim = p->signal->rlim + resource; |
| |
| /* Control the ability to change the hard limit (whether |
| lowering or raising it), so that the hard limit can |
| later be used as a safe reset point for the soft limit |
| upon context transitions. See selinux_bprm_committing_creds. */ |
| if (old_rlim->rlim_max != new_rlim->rlim_max) |
| return avc_has_perm(current_sid(), task_sid_obj(p), |
| SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); |
| |
| return 0; |
| } |
| |
| static int selinux_task_setscheduler(struct task_struct *p) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__SETSCHED, NULL); |
| } |
| |
| static int selinux_task_getscheduler(struct task_struct *p) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__GETSCHED, NULL); |
| } |
| |
| static int selinux_task_movememory(struct task_struct *p) |
| { |
| return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
| PROCESS__SETSCHED, NULL); |
| } |
| |
| static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, |
| int sig, const struct cred *cred) |
| { |
| u32 secid; |
| u32 perm; |
| |
| if (!sig) |
| perm = PROCESS__SIGNULL; /* null signal; existence test */ |
| else |
| perm = signal_to_av(sig); |
| if (!cred) |
| secid = current_sid(); |
| else |
| secid = cred_sid(cred); |
| return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); |
| } |
| |
| static void selinux_task_to_inode(struct task_struct *p, |
| struct inode *inode) |
| { |
| struct inode_security_struct *isec = selinux_inode(inode); |
| u32 sid = task_sid_obj(p); |
| |
| spin_lock(&isec->lock); |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| isec->sid = sid; |
| isec->initialized = LABEL_INITIALIZED; |
| spin_unlock(&isec->lock); |
| } |
| |
| static int selinux_userns_create(const struct cred *cred) |
| { |
| u32 sid = current_sid(); |
| |
| return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, |
| USER_NAMESPACE__CREATE, NULL); |
| } |
| |
| /* Returns error only if unable to parse addresses */ |
| static int selinux_parse_skb_ipv4(struct sk_buff *skb, |
| struct common_audit_data *ad, u8 *proto) |
| { |
| int offset, ihlen, ret = -EINVAL; |
| struct iphdr _iph, *ih; |
| |
| offset = skb_network_offset(skb); |
| ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); |
| if (ih == NULL) |
| goto out; |
| |
| ihlen = ih->ihl * 4; |
| if (ihlen < sizeof(_iph)) |
| goto out; |
| |
| ad->u.net->v4info.saddr = ih->saddr; |
| ad->u.net->v4info.daddr = ih->daddr; |
| ret = 0; |
| |
| if (proto) |
| *proto = ih->protocol; |
| |
| switch (ih->protocol) { |
| case IPPROTO_TCP: { |
| struct tcphdr _tcph, *th; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); |
| if (th == NULL) |
| break; |
| |
| ad->u.net->sport = th->source; |
| ad->u.net->dport = th->dest; |
| break; |
| } |
| |
| case IPPROTO_UDP: { |
| struct udphdr _udph, *uh; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); |
| if (uh == NULL) |
| break; |
| |
| ad->u.net->sport = uh->source; |
| ad->u.net->dport = uh->dest; |
| break; |
| } |
| |
| case IPPROTO_DCCP: { |
| struct dccp_hdr _dccph, *dh; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); |
| if (dh == NULL) |
| break; |
| |
| ad->u.net->sport = dh->dccph_sport; |
| ad->u.net->dport = dh->dccph_dport; |
| break; |
| } |
| |
| #if IS_ENABLED(CONFIG_IP_SCTP) |
| case IPPROTO_SCTP: { |
| struct sctphdr _sctph, *sh; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); |
| if (sh == NULL) |
| break; |
| |
| ad->u.net->sport = sh->source; |
| ad->u.net->dport = sh->dest; |
| break; |
| } |
| #endif |
| default: |
| break; |
| } |
| out: |
| return ret; |
| } |
| |
| #if IS_ENABLED(CONFIG_IPV6) |
| |
| /* Returns error only if unable to parse addresses */ |
| static int selinux_parse_skb_ipv6(struct sk_buff *skb, |
| struct common_audit_data *ad, u8 *proto) |
| { |
| u8 nexthdr; |
| int ret = -EINVAL, offset; |
| struct ipv6hdr _ipv6h, *ip6; |
| __be16 frag_off; |
| |
| offset = skb_network_offset(skb); |
| ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); |
| if (ip6 == NULL) |
| goto out; |
| |
| ad->u.net->v6info.saddr = ip6->saddr; |
| ad->u.net->v6info.daddr = ip6->daddr; |
| ret = 0; |
| |
| nexthdr = ip6->nexthdr; |
| offset += sizeof(_ipv6h); |
| offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); |
| if (offset < 0) |
| goto out; |
| |
| if (proto) |
| *proto = nexthdr; |
| |
| switch (nexthdr) { |
| case IPPROTO_TCP: { |
| struct tcphdr _tcph, *th; |
| |
| th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); |
| if (th == NULL) |
| break; |
| |
| ad->u.net->sport = th->source; |
| ad->u.net->dport = th->dest; |
| break; |
| } |
| |
| case IPPROTO_UDP: { |
| struct udphdr _udph, *uh; |
| |
| uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); |
| if (uh == NULL) |
| break; |
| |
| ad->u.net->sport = uh->source; |
| ad->u.net->dport = uh->dest; |
| break; |
| } |
| |
| case IPPROTO_DCCP: { |
| struct dccp_hdr _dccph, *dh; |
| |
| dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); |
| if (dh == NULL) |
| break; |
| |
| ad->u.net->sport = dh->dccph_sport; |
| ad->u.net->dport = dh->dccph_dport; |
| break; |
| } |
| |
| #if IS_ENABLED(CONFIG_IP_SCTP) |
| case IPPROTO_SCTP: { |
| struct sctphdr _sctph, *sh; |
| |
| sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); |
| if (sh == NULL) |
| break; |
| |
| ad->u.net->sport = sh->source; |
| ad->u.net->dport = sh->dest; |
| break; |
| } |
| #endif |
| /* includes fragments */ |
| default: |
| break; |
| } |
| out: |
| return ret; |
| } |
| |
| #endif /* IPV6 */ |
| |
| static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, |
| char **_addrp, int src, u8 *proto) |
| { |
| char *addrp; |
| int ret; |
| |
| switch (ad->u.net->family) { |
| case PF_INET: |
| ret = selinux_parse_skb_ipv4(skb, ad, proto); |
| if (ret) |
| goto parse_error; |
| addrp = (char *)(src ? &ad->u.net->v4info.saddr : |
| &ad->u.net->v4info.daddr); |
| goto okay; |
| |
| #if IS_ENABLED(CONFIG_IPV6) |
| case PF_INET6: |
| ret = selinux_parse_skb_ipv6(skb, ad, proto); |
| if (ret) |
| goto parse_error; |
| addrp = (char *)(src ? &ad->u.net->v6info.saddr : |
| &ad->u.net->v6info.daddr); |
| goto okay; |
| #endif /* IPV6 */ |
| default: |
| addrp = NULL; |
| goto okay; |
| } |
| |
| parse_error: |
| pr_warn( |
| "SELinux: failure in selinux_parse_skb()," |
| " unable to parse packet\n"); |
| return ret; |
| |
| okay: |
| if (_addrp) |
| *_addrp = addrp; |
| return 0; |
| } |
| |
| /** |
| * selinux_skb_peerlbl_sid - Determine the peer label of a packet |
| * @skb: the packet |
| * @family: protocol family |
| * @sid: the packet's peer label SID |
| * |
| * Description: |
| * Check the various different forms of network peer labeling and determine |
| * the peer label/SID for the packet; most of the magic actually occurs in |
| * the security server function security_net_peersid_cmp(). The function |
| * returns zero if the value in @sid is valid (although it may be SECSID_NULL) |
| * or -EACCES if @sid is invalid due to inconsistencies with the different |
| * peer labels. |
| * |
| */ |
| static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) |
| { |
| int err; |
| u32 xfrm_sid; |
| u32 nlbl_sid; |
| u32 nlbl_type; |
| |
| err = selinux_xfrm_skb_sid(skb, &xfrm_sid); |
| if (unlikely(err)) |
| return -EACCES; |
| err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); |
| if (unlikely(err)) |
| return -EACCES; |
| |
| err = security_net_peersid_resolve(nlbl_sid, |
| nlbl_type, xfrm_sid, sid); |
| if (unlikely(err)) { |
| pr_warn( |
| "SELinux: failure in selinux_skb_peerlbl_sid()," |
| " unable to determine packet's peer label\n"); |
| return -EACCES; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * selinux_conn_sid - Determine the child socket label for a connection |
| * @sk_sid: the parent socket's SID |
| * @skb_sid: the packet's SID |
| * @conn_sid: the resulting connection SID |
| * |
| * If @skb_sid is valid then the user:role:type information from @sk_sid is |
| * combined with the MLS information from @skb_sid in order to create |
| * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy |
| * of @sk_sid. Returns zero on success, negative values on failure. |
| * |
| */ |
| static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) |
| { |
| int err = 0; |
| |
| if (skb_sid != SECSID_NULL) |
| err = security_sid_mls_copy(sk_sid, skb_sid, |
| conn_sid); |
| else |
| *conn_sid = sk_sid; |
| |
| return err; |
| } |
| |
| /* socket security operations */ |
| |
| static int socket_sockcreate_sid(const struct task_security_struct *tsec, |
| u16 secclass, u32 *socksid) |
| { |
| if (tsec->sockcreate_sid > SECSID_NULL) { |
| *socksid = tsec->sockcreate_sid; |
| return 0; |
| } |
| |
| return security_transition_sid(tsec->sid, tsec->sid, |
| secclass, NULL, socksid); |
| } |
| |
| static int sock_has_perm(struct sock *sk, u32 perms) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| |
| if (sksec->sid == SECINITSID_KERNEL) |
| return 0; |
| |
| /* |
| * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that |
| * inherited the kernel context from early boot used to be skipped |
| * here, so preserve that behavior unless the capability is set. |
| * |
| * By setting the capability the policy signals that it is ready |
| * for this quirk to be fixed. Note that sockets created by a kernel |
| * thread or a usermode helper executed without a transition will |
| * still be skipped in this check regardless of the policycap |
| * setting. |
| */ |
| if (!selinux_policycap_userspace_initial_context() && |
| sksec->sid == SECINITSID_INIT) |
| return 0; |
| |
| ad_net_init_from_sk(&ad, &net, sk); |
| |
| return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, |
| &ad); |
| } |
| |
| static int selinux_socket_create(int family, int type, |
| int protocol, int kern) |
| { |
| const struct task_security_struct *tsec = selinux_cred(current_cred()); |
| u32 newsid; |
| u16 secclass; |
| int rc; |
| |
| if (kern) |
| return 0; |
| |
| secclass = socket_type_to_security_class(family, type, protocol); |
| rc = socket_sockcreate_sid(tsec, secclass, &newsid); |
| if (rc) |
| return rc; |
| |
| return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); |
| } |
| |
| static int selinux_socket_post_create(struct socket *sock, int family, |
| int type, int protocol, int kern) |
| { |
| const struct task_security_struct *tsec = selinux_cred(current_cred()); |
| struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); |
| struct sk_security_struct *sksec; |
| u16 sclass = socket_type_to_security_class(family, type, protocol); |
| u32 sid = SECINITSID_KERNEL; |
| int err = 0; |
| |
| if (!kern) { |
| err = socket_sockcreate_sid(tsec, sclass, &sid); |
| if (err) |
| return err; |
| } |
| |
| isec->sclass = sclass; |
| isec->sid = sid; |
| isec->initialized = LABEL_INITIALIZED; |
| |
| if (sock->sk) { |
| sksec = sock->sk->sk_security; |
| sksec->sclass = sclass; |
| sksec->sid = sid; |
| /* Allows detection of the first association on this socket */ |
| if (sksec->sclass == SECCLASS_SCTP_SOCKET) |
| sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; |
| |
| err = selinux_netlbl_socket_post_create(sock->sk, family); |
| } |
| |
| return err; |
| } |
| |
| static int selinux_socket_socketpair(struct socket *socka, |
| struct socket *sockb) |
| { |
| struct sk_security_struct *sksec_a = socka->sk->sk_security; |
| struct sk_security_struct *sksec_b = sockb->sk->sk_security; |
| |
| sksec_a->peer_sid = sksec_b->sid; |
| sksec_b->peer_sid = sksec_a->sid; |
| |
| return 0; |
| } |
| |
| /* Range of port numbers used to automatically bind. |
| Need to determine whether we should perform a name_bind |
| permission check between the socket and the port number. */ |
| |
| static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) |
| { |
| struct sock *sk = sock->sk; |
| struct sk_security_struct *sksec = sk->sk_security; |
| u16 family; |
| int err; |
| |
| err = sock_has_perm(sk, SOCKET__BIND); |
| if (err) |
| goto out; |
| |
| /* If PF_INET or PF_INET6, check name_bind permission for the port. */ |
| family = sk->sk_family; |
| if (family == PF_INET || family == PF_INET6) { |
| char *addrp; |
| struct common_audit_data ad; |
| struct lsm_network_audit net = {0,}; |
| struct sockaddr_in *addr4 = NULL; |
| struct sockaddr_in6 *addr6 = NULL; |
| u16 family_sa; |
| unsigned short snum; |
| u32 sid, node_perm; |
| |
| /* |
| * sctp_bindx(3) calls via selinux_sctp_bind_connect() |
| * that validates multiple binding addresses. Because of this |
| * need to check address->sa_family as it is possible to have |
| * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. |
| */ |
| if (addrlen < offsetofend(struct sockaddr, sa_family)) |
| return -EINVAL; |
| family_sa = address->sa_family; |
| switch (family_sa) { |
| case AF_UNSPEC: |
| case AF_INET: |
| if (addrlen < sizeof(struct sockaddr_in)) |
| return -EINVAL; |
| addr4 = (struct sockaddr_in *)address; |
| if (family_sa == AF_UNSPEC) { |
| if (family == PF_INET6) { |
| /* Length check from inet6_bind_sk() */ |
| if (addrlen < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| /* Family check from __inet6_bind() */ |
| goto err_af; |
| } |
| /* see __inet_bind(), we only want to allow |
| * AF_UNSPEC if the address is INADDR_ANY |
| */ |
| if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) |
| goto err_af; |
| family_sa = AF_INET; |
| } |
| snum = ntohs(addr4->sin_port); |
| addrp = (char *)&addr4->sin_addr.s_addr; |
| break; |
| case AF_INET6: |
| if (addrlen < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| addr6 = (struct sockaddr_in6 *)address; |
| snum = ntohs(addr6->sin6_port); |
| addrp = (char *)&addr6->sin6_addr.s6_addr; |
| break; |
| default: |
| goto err_af; |
| } |
| |
| ad.type = LSM_AUDIT_DATA_NET; |
| ad.u.net = &net; |
| ad.u.net->sport = htons(snum); |
| ad.u.net->family = family_sa; |
| |
| if (snum) { |
| int low, high; |
| |
| inet_get_local_port_range(sock_net(sk), &low, &high); |
| |
| if (inet_port_requires_bind_service(sock_net(sk), snum) || |
| snum < low || snum > high) { |
| err = sel_netport_sid(sk->sk_protocol, |
| snum, &sid); |
| if (err) |
| goto out; |
| err = avc_has_perm(sksec->sid, sid, |
| sksec->sclass, |
| SOCKET__NAME_BIND, &ad); |
| if (err) |
| goto out; |
| } |
| } |
| |
| switch (sksec->sclass) { |
| case SECCLASS_TCP_SOCKET: |
| node_perm = TCP_SOCKET__NODE_BIND; |
| break; |
| |
| case SECCLASS_UDP_SOCKET: |
| node_perm = UDP_SOCKET__NODE_BIND; |
| break; |
| |
| case SECCLASS_DCCP_SOCKET: |
| node_perm = DCCP_SOCKET__NODE_BIND; |
| break; |
| |
| case SECCLASS_SCTP_SOCKET: |
| node_perm = SCTP_SOCKET__NODE_BIND; |
| break; |
| |
| default: |
| node_perm = RAWIP_SOCKET__NODE_BIND; |
| break; |
| } |
| |
| err = sel_netnode_sid(addrp, family_sa, &sid); |
| if (err) |
| goto out; |
| |
| if (family_sa == AF_INET) |
| ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; |
| else |
| ad.u.net->v6info.saddr = addr6->sin6_addr; |
| |
| err = avc_has_perm(sksec->sid, sid, |
| sksec->sclass, node_perm, &ad); |
| if (err) |
| goto out; |
| } |
| out: |
| return err; |
| err_af: |
| /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ |
| if (sksec->sclass == SECCLASS_SCTP_SOCKET) |
| return -EINVAL; |
| return -EAFNOSUPPORT; |
| } |
| |
| /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) |
| * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst |
| */ |
| static int selinux_socket_connect_helper(struct socket *sock, |
| struct sockaddr *address, int addrlen) |
| { |
| struct sock *sk = sock->sk; |
| struct sk_security_struct *sksec = sk->sk_security; |
| int err; |
| |
| err = sock_has_perm(sk, SOCKET__CONNECT); |
| if (err) |
| return err; |
| if (addrlen < offsetofend(struct sockaddr, sa_family)) |
| return -EINVAL; |
| |
| /* connect(AF_UNSPEC) has special handling, as it is a documented |
| * way to disconnect the socket |
| */ |
| if (address->sa_family == AF_UNSPEC) |
| return 0; |
| |
| /* |
| * If a TCP, DCCP or SCTP socket, check name_connect permission |
| * for the port. |
| */ |
| if (sksec->sclass == SECCLASS_TCP_SOCKET || |
| sksec->sclass == SECCLASS_DCCP_SOCKET || |
| sksec->sclass == SECCLASS_SCTP_SOCKET) { |
| struct common_audit_data ad; |
| struct lsm_network_audit net = {0,}; |
| struct sockaddr_in *addr4 = NULL; |
| struct sockaddr_in6 *addr6 = NULL; |
| unsigned short snum; |
| u32 sid, perm; |
| |
| /* sctp_connectx(3) calls via selinux_sctp_bind_connect() |
| * that validates multiple connect addresses. Because of this |
| * need to check address->sa_family as it is possible to have |
| * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. |
| */ |
| switch (address->sa_family) { |
| case AF_INET: |
| addr4 = (struct sockaddr_in *)address; |
| if (addrlen < sizeof(struct sockaddr_in)) |
| return -EINVAL; |
| snum = ntohs(addr4->sin_port); |
| break; |
| case AF_INET6: |
| addr6 = (struct sockaddr_in6 *)address; |
| if (addrlen < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| snum = ntohs(addr6->sin6_port); |
| break; |
| default: |
| /* Note that SCTP services expect -EINVAL, whereas |
| * others expect -EAFNOSUPPORT. |
| */ |
| if (sksec->sclass == SECCLASS_SCTP_SOCKET) |
| return -EINVAL; |
| else |
| return -EAFNOSUPPORT; |
| } |
| |
| err = sel_netport_sid(sk->sk_protocol, snum, &sid); |
| if (err) |
| return err; |
| |
| switch (sksec->sclass) { |
| case SECCLASS_TCP_SOCKET: |
| perm = TCP_SOCKET__NAME_CONNECT; |
| break; |
| case SECCLASS_DCCP_SOCKET: |
| perm = DCCP_SOCKET__NAME_CONNECT; |
| break; |
| case SECCLASS_SCTP_SOCKET: |
| perm = SCTP_SOCKET__NAME_CONNECT; |
| break; |
| } |
| |
| ad.type = LSM_AUDIT_DATA_NET; |
| ad.u.net = &net; |
| ad.u.net->dport = htons(snum); |
| ad.u.net->family = address->sa_family; |
| err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); |
| if (err) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| /* Supports connect(2), see comments in selinux_socket_connect_helper() */ |
| static int selinux_socket_connect(struct socket *sock, |
| struct sockaddr *address, int addrlen) |
| { |
| int err; |
| struct sock *sk = sock->sk; |
| |
| err = selinux_socket_connect_helper(sock, address, addrlen); |
| if (err) |
| return err; |
| |
| return selinux_netlbl_socket_connect(sk, address); |
| } |
| |
| static int selinux_socket_listen(struct socket *sock, int backlog) |
| { |
| return sock_has_perm(sock->sk, SOCKET__LISTEN); |
| } |
| |
| static int selinux_socket_accept(struct socket *sock, struct socket *newsock) |
| { |
| int err; |
| struct inode_security_struct *isec; |
| struct inode_security_struct *newisec; |
| u16 sclass; |
| u32 sid; |
| |
| err = sock_has_perm(sock->sk, SOCKET__ACCEPT); |
| if (err) |
| return err; |
| |
| isec = inode_security_novalidate(SOCK_INODE(sock)); |
| spin_lock(&isec->lock); |
| sclass = isec->sclass; |
| sid = isec->sid; |
| spin_unlock(&isec->lock); |
| |
| newisec = inode_security_novalidate(SOCK_INODE(newsock)); |
| newisec->sclass = sclass; |
| newisec->sid = sid; |
| newisec->initialized = LABEL_INITIALIZED; |
| |
| return 0; |
| } |
| |
| static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, |
| int size) |
| { |
| return sock_has_perm(sock->sk, SOCKET__WRITE); |
| } |
| |
| static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, |
| int size, int flags) |
| { |
| return sock_has_perm(sock->sk, SOCKET__READ); |
| } |
| |
| static int selinux_socket_getsockname(struct socket *sock) |
| { |
| return sock_has_perm(sock->sk, SOCKET__GETATTR); |
| } |
| |
| static int selinux_socket_getpeername(struct socket *sock) |
| { |
| return sock_has_perm(sock->sk, SOCKET__GETATTR); |
| } |
| |
| static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) |
| { |
| int err; |
| |
| err = sock_has_perm(sock->sk, SOCKET__SETOPT); |
| if (err) |
| return err; |
| |
| return selinux_netlbl_socket_setsockopt(sock, level, optname); |
| } |
| |
| static int selinux_socket_getsockopt(struct socket *sock, int level, |
| int optname) |
| { |
| return sock_has_perm(sock->sk, SOCKET__GETOPT); |
| } |
| |
| static int selinux_socket_shutdown(struct socket *sock, int how) |
| { |
| return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); |
| } |
| |
| static int selinux_socket_unix_stream_connect(struct sock *sock, |
| struct sock *other, |
| struct sock *newsk) |
| { |
| struct sk_security_struct *sksec_sock = sock->sk_security; |
| struct sk_security_struct *sksec_other = other->sk_security; |
| struct sk_security_struct *sksec_new = newsk->sk_security; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| int err; |
| |
| ad_net_init_from_sk(&ad, &net, other); |
| |
| err = avc_has_perm(sksec_sock->sid, sksec_other->sid, |
| sksec_other->sclass, |
| UNIX_STREAM_SOCKET__CONNECTTO, &ad); |
| if (err) |
| return err; |
| |
| /* server child socket */ |
| sksec_new->peer_sid = sksec_sock->sid; |
| err = security_sid_mls_copy(sksec_other->sid, |
| sksec_sock->sid, &sksec_new->sid); |
| if (err) |
| return err; |
| |
| /* connecting socket */ |
| sksec_sock->peer_sid = sksec_new->sid; |
| |
| return 0; |
| } |
| |
| static int selinux_socket_unix_may_send(struct socket *sock, |
| struct socket *other) |
| { |
| struct sk_security_struct *ssec = sock->sk->sk_security; |
| struct sk_security_struct *osec = other->sk->sk_security; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| |
| ad_net_init_from_sk(&ad, &net, other->sk); |
| |
| return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, |
| &ad); |
| } |
| |
| static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, |
| char *addrp, u16 family, u32 peer_sid, |
| struct common_audit_data *ad) |
| { |
| int err; |
| u32 if_sid; |
| u32 node_sid; |
| |
| err = sel_netif_sid(ns, ifindex, &if_sid); |
| if (err) |
| return err; |
| err = avc_has_perm(peer_sid, if_sid, |
| SECCLASS_NETIF, NETIF__INGRESS, ad); |
| if (err) |
| return err; |
| |
| err = sel_netnode_sid(addrp, family, &node_sid); |
| if (err) |
| return err; |
| return avc_has_perm(peer_sid, node_sid, |
| SECCLASS_NODE, NODE__RECVFROM, ad); |
| } |
| |
| static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, |
| u16 family) |
| { |
| int err = 0; |
| struct sk_security_struct *sksec = sk->sk_security; |
| u32 sk_sid = sksec->sid; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| char *addrp; |
| |
| ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); |
| err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); |
| if (err) |
| return err; |
| |
| if (selinux_secmark_enabled()) { |
| err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, |
| PACKET__RECV, &ad); |
| if (err) |
| return err; |
| } |
| |
| err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); |
| if (err) |
| return err; |
| err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); |
| |
| return err; |
| } |
| |
| static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| { |
| int err, peerlbl_active, secmark_active; |
| struct sk_security_struct *sksec = sk->sk_security; |
| u16 family = sk->sk_family; |
| u32 sk_sid = sksec->sid; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| char *addrp; |
| |
| if (family != PF_INET && family != PF_INET6) |
| return 0; |
| |
| /* Handle mapped IPv4 packets arriving via IPv6 sockets */ |
| if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| |
| /* If any sort of compatibility mode is enabled then handoff processing |
| * to the selinux_sock_rcv_skb_compat() function to deal with the |
| * special handling. We do this in an attempt to keep this function |
| * as fast and as clean as possible. */ |
| if (!selinux_policycap_netpeer()) |
| return selinux_sock_rcv_skb_compat(sk, skb, family); |
| |
| secmark_active = selinux_secmark_enabled(); |
| peerlbl_active = selinux_peerlbl_enabled(); |
| if (!secmark_active && !peerlbl_active) |
| return 0; |
| |
| ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); |
| err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); |
| if (err) |
| return err; |
| |
| if (peerlbl_active) { |
| u32 peer_sid; |
| |
| err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); |
| if (err) |
| return err; |
| err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, |
| addrp, family, peer_sid, &ad); |
| if (err) { |
| selinux_netlbl_err(skb, family, err, 0); |
| return err; |
| } |
| err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, |
| PEER__RECV, &ad); |
| if (err) { |
| selinux_netlbl_err(skb, family, err, 0); |
| return err; |
| } |
| } |
| |
| if (secmark_active) { |
| err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, |
| PACKET__RECV, &ad); |
| if (err) |
| return err; |
| } |
| |
| return err; |
| } |
| |
| static int selinux_socket_getpeersec_stream(struct socket *sock, |
| sockptr_t optval, sockptr_t optlen, |
| unsigned int len) |
| { |
| int err = 0; |
| char *scontext = NULL; |
| u32 scontext_len; |
| struct sk_security_struct *sksec = sock->sk->sk_security; |
| u32 peer_sid = SECSID_NULL; |
| |
| if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || |
| sksec->sclass == SECCLASS_TCP_SOCKET || |
| sksec->sclass == SECCLASS_SCTP_SOCKET) |
| peer_sid = sksec->peer_sid; |
| if (peer_sid == SECSID_NULL) |
| return -ENOPROTOOPT; |
| |
| err = security_sid_to_context(peer_sid, &scontext, |
| &scontext_len); |
| if (err) |
| return err; |
| if (scontext_len > len) { |
| err = -ERANGE; |
| goto out_len; |
| } |
| |
| if (copy_to_sockptr(optval, scontext, scontext_len)) |
| err = -EFAULT; |
| out_len: |
| if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) |
| err = -EFAULT; |
| kfree(scontext); |
| return err; |
| } |
| |
| static int selinux_socket_getpeersec_dgram(struct socket *sock, |
| struct sk_buff *skb, u32 *secid) |
| { |
| u32 peer_secid = SECSID_NULL; |
| u16 family; |
| |
| if (skb && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| else if (skb && skb->protocol == htons(ETH_P_IPV6)) |
| family = PF_INET6; |
| else if (sock) |
| family = sock->sk->sk_family; |
| else { |
| *secid = SECSID_NULL; |
| return -EINVAL; |
| } |
| |
| if (sock && family == PF_UNIX) { |
| struct inode_security_struct *isec; |
| isec = inode_security_novalidate(SOCK_INODE(sock)); |
| peer_secid = isec->sid; |
| } else if (skb) |
| selinux_skb_peerlbl_sid(skb, family, &peer_secid); |
| |
| *secid = peer_secid; |
| if (peer_secid == SECSID_NULL) |
| return -ENOPROTOOPT; |
| return 0; |
| } |
| |
| static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
| { |
| struct sk_security_struct *sksec; |
| |
| sksec = kzalloc(sizeof(*sksec), priority); |
| if (!sksec) |
| return -ENOMEM; |
| |
| sksec->peer_sid = SECINITSID_UNLABELED; |
| sksec->sid = SECINITSID_UNLABELED; |
| sksec->sclass = SECCLASS_SOCKET; |
| selinux_netlbl_sk_security_reset(sksec); |
| sk->sk_security = sksec; |
| |
| return 0; |
| } |
| |
| static void selinux_sk_free_security(struct sock *sk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| sk->sk_security = NULL; |
| selinux_netlbl_sk_security_free(sksec); |
| kfree(sksec); |
| } |
| |
| static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct sk_security_struct *newsksec = newsk->sk_security; |
| |
| newsksec->sid = sksec->sid; |
| newsksec->peer_sid = sksec->peer_sid; |
| newsksec->sclass = sksec->sclass; |
| |
| selinux_netlbl_sk_security_reset(newsksec); |
| } |
| |
| static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) |
| { |
| if (!sk) |
| *secid = SECINITSID_ANY_SOCKET; |
| else { |
| const struct sk_security_struct *sksec = sk->sk_security; |
| |
| *secid = sksec->sid; |
| } |
| } |
| |
| static void selinux_sock_graft(struct sock *sk, struct socket *parent) |
| { |
| struct inode_security_struct *isec = |
| inode_security_novalidate(SOCK_INODE(parent)); |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || |
| sk->sk_family == PF_UNIX) |
| isec->sid = sksec->sid; |
| sksec->sclass = isec->sclass; |
| } |
| |
| /* |
| * Determines peer_secid for the asoc and updates socket's peer label |
| * if it's the first association on the socket. |
| */ |
| static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, |
| struct sk_buff *skb) |
| { |
| struct sock *sk = asoc->base.sk; |
| u16 family = sk->sk_family; |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| int err; |
| |
| /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
| if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| |
| if (selinux_peerlbl_enabled()) { |
| asoc->peer_secid = SECSID_NULL; |
| |
| /* This will return peer_sid = SECSID_NULL if there are |
| * no peer labels, see security_net_peersid_resolve(). |
| */ |
| err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); |
| if (err) |
| return err; |
| |
| if (asoc->peer_secid == SECSID_NULL) |
| asoc->peer_secid = SECINITSID_UNLABELED; |
| } else { |
| asoc->peer_secid = SECINITSID_UNLABELED; |
| } |
| |
| if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { |
| sksec->sctp_assoc_state = SCTP_ASSOC_SET; |
| |
| /* Here as first association on socket. As the peer SID |
| * was allowed by peer recv (and the netif/node checks), |
| * then it is approved by policy and used as the primary |
| * peer SID for getpeercon(3). |
| */ |
| sksec->peer_sid = asoc->peer_secid; |
| } else if (sksec->peer_sid != asoc->peer_secid) { |
| /* Other association peer SIDs are checked to enforce |
| * consistency among the peer SIDs. |
| */ |
| ad_net_init_from_sk(&ad, &net, asoc->base.sk); |
| err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, |
| sksec->sclass, SCTP_SOCKET__ASSOCIATION, |
| &ad); |
| if (err) |
| return err; |
| } |
| return 0; |
| } |
| |
| /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This |
| * happens on an incoming connect(2), sctp_connectx(3) or |
| * sctp_sendmsg(3) (with no association already present). |
| */ |
| static int selinux_sctp_assoc_request(struct sctp_association *asoc, |
| struct sk_buff *skb) |
| { |
| struct sk_security_struct *sksec = asoc->base.sk->sk_security; |
| u32 conn_sid; |
| int err; |
| |
| if (!selinux_policycap_extsockclass()) |
| return 0; |
| |
| err = selinux_sctp_process_new_assoc(asoc, skb); |
| if (err) |
| return err; |
| |
| /* Compute the MLS component for the connection and store |
| * the information in asoc. This will be used by SCTP TCP type |
| * sockets and peeled off connections as they cause a new |
| * socket to be generated. selinux_sctp_sk_clone() will then |
| * plug this into the new socket. |
| */ |
| err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); |
| if (err) |
| return err; |
| |
| asoc->secid = conn_sid; |
| |
| /* Set any NetLabel labels including CIPSO/CALIPSO options. */ |
| return selinux_netlbl_sctp_assoc_request(asoc, skb); |
| } |
| |
| /* Called when SCTP receives a COOKIE ACK chunk as the final |
| * response to an association request (initited by us). |
| */ |
| static int selinux_sctp_assoc_established(struct sctp_association *asoc, |
| struct sk_buff *skb) |
| { |
| struct sk_security_struct *sksec = asoc->base.sk->sk_security; |
| |
| if (!selinux_policycap_extsockclass()) |
| return 0; |
| |
| /* Inherit secid from the parent socket - this will be picked up |
| * by selinux_sctp_sk_clone() if the association gets peeled off |
| * into a new socket. |
| */ |
| asoc->secid = sksec->sid; |
| |
| return selinux_sctp_process_new_assoc(asoc, skb); |
| } |
| |
| /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting |
| * based on their @optname. |
| */ |
| static int selinux_sctp_bind_connect(struct sock *sk, int optname, |
| struct sockaddr *address, |
| int addrlen) |
| { |
| int len, err = 0, walk_size = 0; |
| void *addr_buf; |
| struct sockaddr *addr; |
| struct socket *sock; |
| |
| if (!selinux_policycap_extsockclass()) |
| return 0; |
| |
| /* Process one or more addresses that may be IPv4 or IPv6 */ |
| sock = sk->sk_socket; |
| addr_buf = address; |
| |
| while (walk_size < addrlen) { |
| if (walk_size + sizeof(sa_family_t) > addrlen) |
| return -EINVAL; |
| |
| addr = addr_buf; |
| switch (addr->sa_family) { |
| case AF_UNSPEC: |
| case AF_INET: |
| len = sizeof(struct sockaddr_in); |
| break; |
| case AF_INET6: |
| len = sizeof(struct sockaddr_in6); |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| if (walk_size + len > addrlen) |
| return -EINVAL; |
| |
| err = -EINVAL; |
| switch (optname) { |
| /* Bind checks */ |
| case SCTP_PRIMARY_ADDR: |
| case SCTP_SET_PEER_PRIMARY_ADDR: |
| case SCTP_SOCKOPT_BINDX_ADD: |
| err = selinux_socket_bind(sock, addr, len); |
| break; |
| /* Connect checks */ |
| case SCTP_SOCKOPT_CONNECTX: |
| case SCTP_PARAM_SET_PRIMARY: |
| case SCTP_PARAM_ADD_IP: |
| case SCTP_SENDMSG_CONNECT: |
| err = selinux_socket_connect_helper(sock, addr, len); |
| if (err) |
| return err; |
| |
| /* As selinux_sctp_bind_connect() is called by the |
| * SCTP protocol layer, the socket is already locked, |
| * therefore selinux_netlbl_socket_connect_locked() |
| * is called here. The situations handled are: |
| * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), |
| * whenever a new IP address is added or when a new |
| * primary address is selected. |
| * Note that an SCTP connect(2) call happens before |
| * the SCTP protocol layer and is handled via |
| * selinux_socket_connect(). |
| */ |
| err = selinux_netlbl_socket_connect_locked(sk, addr); |
| break; |
| } |
| |
| if (err) |
| return err; |
| |
| addr_buf += len; |
| walk_size += len; |
| } |
| |
| return 0; |
| } |
| |
| /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ |
| static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, |
| struct sock *newsk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct sk_security_struct *newsksec = newsk->sk_security; |
| |
| /* If policy does not support SECCLASS_SCTP_SOCKET then call |
| * the non-sctp clone version. |
| */ |
| if (!selinux_policycap_extsockclass()) |
| return selinux_sk_clone_security(sk, newsk); |
| |
| newsksec->sid = asoc->secid; |
| newsksec->peer_sid = asoc->peer_secid; |
| newsksec->sclass = sksec->sclass; |
| selinux_netlbl_sctp_sk_clone(sk, newsk); |
| } |
| |
| static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) |
| { |
| struct sk_security_struct *ssksec = ssk->sk_security; |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| ssksec->sclass = sksec->sclass; |
| ssksec->sid = sksec->sid; |
| |
| /* replace the existing subflow label deleting the existing one |
| * and re-recreating a new label using the updated context |
| */ |
| selinux_netlbl_sk_security_free(ssksec); |
| return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); |
| } |
| |
| static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, |
| struct request_sock *req) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| int err; |
| u16 family = req->rsk_ops->family; |
| u32 connsid; |
| u32 peersid; |
| |
| err = selinux_skb_peerlbl_sid(skb, family, &peersid); |
| if (err) |
| return err; |
| err = selinux_conn_sid(sksec->sid, peersid, &connsid); |
| if (err) |
| return err; |
| req->secid = connsid; |
| req->peer_secid = peersid; |
| |
| return selinux_netlbl_inet_conn_request(req, family); |
| } |
| |
| static void selinux_inet_csk_clone(struct sock *newsk, |
| const struct request_sock *req) |
| { |
| struct sk_security_struct *newsksec = newsk->sk_security; |
| |
| newsksec->sid = req->secid; |
| newsksec->peer_sid = req->peer_secid; |
| /* NOTE: Ideally, we should also get the isec->sid for the |
| new socket in sync, but we don't have the isec available yet. |
| So we will wait until sock_graft to do it, by which |
| time it will have been created and available. */ |
| |
| /* We don't need to take any sort of lock here as we are the only |
| * thread with access to newsksec */ |
| selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); |
| } |
| |
| static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) |
| { |
| u16 family = sk->sk_family; |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
| if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| |
| selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); |
| } |
| |
| static int selinux_secmark_relabel_packet(u32 sid) |
| { |
| return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO, |
| NULL); |
| } |
| |
| static void selinux_secmark_refcount_inc(void) |
| { |
| atomic_inc(&selinux_secmark_refcount); |
| } |
| |
| static void selinux_secmark_refcount_dec(void) |
| { |
| atomic_dec(&selinux_secmark_refcount); |
| } |
| |
| static void selinux_req_classify_flow(const struct request_sock *req, |
| struct flowi_common *flic) |
| { |
| flic->flowic_secid = req->secid; |
| } |
| |
| static int selinux_tun_dev_alloc_security(void **security) |
| { |
| struct tun_security_struct *tunsec; |
| |
| tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); |
| if (!tunsec) |
| return -ENOMEM; |
| tunsec->sid = current_sid(); |
| |
| *security = tunsec; |
| return 0; |
| } |
| |
| static void selinux_tun_dev_free_security(void *security) |
| { |
| kfree(security); |
| } |
| |
| static int selinux_tun_dev_create(void) |
| { |
| u32 sid = current_sid(); |
| |
| /* we aren't taking into account the "sockcreate" SID since the socket |
| * that is being created here is not a socket in the traditional sense, |
| * instead it is a private sock, accessible only to the kernel, and |
| * representing a wide range of network traffic spanning multiple |
| * connections unlike traditional sockets - check the TUN driver to |
| * get a better understanding of why this socket is special */ |
| |
| return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, |
| NULL); |
| } |
| |
| static int selinux_tun_dev_attach_queue(void *security) |
| { |
| struct tun_security_struct *tunsec = security; |
| |
| return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, |
| TUN_SOCKET__ATTACH_QUEUE, NULL); |
| } |
| |
| static int selinux_tun_dev_attach(struct sock *sk, void *security) |
| { |
| struct tun_security_struct *tunsec = security; |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| /* we don't currently perform any NetLabel based labeling here and it |
| * isn't clear that we would want to do so anyway; while we could apply |
| * labeling without the support of the TUN user the resulting labeled |
| * traffic from the other end of the connection would almost certainly |
| * cause confusion to the TUN user that had no idea network labeling |
| * protocols were being used */ |
| |
| sksec->sid = tunsec->sid; |
| sksec->sclass = SECCLASS_TUN_SOCKET; |
| |
| return 0; |
| } |
| |
| static int selinux_tun_dev_open(void *security) |
| { |
| struct tun_security_struct *tunsec = security; |
| u32 sid = current_sid(); |
| int err; |
| |
| err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, |
| TUN_SOCKET__RELABELFROM, NULL); |
| if (err) |
| return err; |
| err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, |
| TUN_SOCKET__RELABELTO, NULL); |
| if (err) |
| return err; |
| tunsec->sid = sid; |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_NETFILTER |
| |
| static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, |
| const struct nf_hook_state *state) |
| { |
| int ifindex; |
| u16 family; |
| char *addrp; |
| u32 peer_sid; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| int secmark_active, peerlbl_active; |
| |
| if (!selinux_policycap_netpeer()) |
| return NF_ACCEPT; |
| |
| secmark_active = selinux_secmark_enabled(); |
| peerlbl_active = selinux_peerlbl_enabled(); |
| if (!secmark_active && !peerlbl_active) |
| return NF_ACCEPT; |
| |
| family = state->pf; |
| if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) |
| return NF_DROP; |
| |
| ifindex = state->in->ifindex; |
| ad_net_init_from_iif(&ad, &net, ifindex, family); |
| if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) |
| return NF_DROP; |
| |
| if (peerlbl_active) { |
| int err; |
| |
| err = selinux_inet_sys_rcv_skb(state->net, ifindex, |
| addrp, family, peer_sid, &ad); |
| if (err) { |
| selinux_netlbl_err(skb, family, err, 1); |
| return NF_DROP; |
| } |
| } |
| |
| if (secmark_active) |
| if (avc_has_perm(peer_sid, skb->secmark, |
| SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) |
| return NF_DROP; |
| |
| if (netlbl_enabled()) |
| /* we do this in the FORWARD path and not the POST_ROUTING |
| * path because we want to make sure we apply the necessary |
| * labeling before IPsec is applied so we can leverage AH |
| * protection */ |
| if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) |
| return NF_DROP; |
| |
| return NF_ACCEPT; |
| } |
| |
| static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, |
| const struct nf_hook_state *state) |
| { |
| struct sock *sk; |
| u32 sid; |
| |
| if (!netlbl_enabled()) |
| return NF_ACCEPT; |
| |
| /* we do this in the LOCAL_OUT path and not the POST_ROUTING path |
| * because we want to make sure we apply the necessary labeling |
| * before IPsec is applied so we can leverage AH protection */ |
| sk = skb->sk; |
| if (sk) { |
| struct sk_security_struct *sksec; |
| |
| if (sk_listener(sk)) |
| /* if the socket is the listening state then this |
| * packet is a SYN-ACK packet which means it needs to |
| * be labeled based on the connection/request_sock and |
| * not the parent socket. unfortunately, we can't |
| * lookup the request_sock yet as it isn't queued on |
| * the parent socket until after the SYN-ACK is sent. |
| * the "solution" is to simply pass the packet as-is |
| * as any IP option based labeling should be copied |
| * from the initial connection request (in the IP |
| * layer). it is far from ideal, but until we get a |
| * security label in the packet itself this is the |
| * best we can do. */ |
| return NF_ACCEPT; |
| |
| /* standard practice, label using the parent socket */ |
| sksec = sk->sk_security; |
| sid = sksec->sid; |
| } else |
| sid = SECINITSID_KERNEL; |
| if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) |
| return NF_DROP; |
| |
| return NF_ACCEPT; |
| } |
| |
| |
| static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, |
| const struct nf_hook_state *state) |
| { |
| struct sock *sk; |
| struct sk_security_struct *sksec; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| u8 proto = 0; |
| |
| sk = skb_to_full_sk(skb); |
| if (sk == NULL) |
| return NF_ACCEPT; |
| sksec = sk->sk_security; |
| |
| ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); |
| if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) |
| return NF_DROP; |
| |
| if (selinux_secmark_enabled()) |
| if (avc_has_perm(sksec->sid, skb->secmark, |
| SECCLASS_PACKET, PACKET__SEND, &ad)) |
| return NF_DROP_ERR(-ECONNREFUSED); |
| |
| if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) |
| return NF_DROP_ERR(-ECONNREFUSED); |
| |
| return NF_ACCEPT; |
| } |
| |
| static unsigned int selinux_ip_postroute(void *priv, |
| struct sk_buff *skb, |
| const struct nf_hook_state *state) |
| { |
| u16 family; |
| u32 secmark_perm; |
| u32 peer_sid; |
| int ifindex; |
| struct sock *sk; |
| struct common_audit_data ad; |
| struct lsm_network_audit net; |
| char *addrp; |
| int secmark_active, peerlbl_active; |
| |
| /* If any sort of compatibility mode is enabled then handoff processing |
| * to the selinux_ip_postroute_compat() function to deal with the |
| * special handling. We do this in an attempt to keep this function |
| * as fast and as clean as possible. */ |
| if (!selinux_policycap_netpeer()) |
| return selinux_ip_postroute_compat(skb, state); |
| |
| secmark_active = selinux_secmark_enabled(); |
| peerlbl_active = selinux_peerlbl_enabled(); |
| if (!secmark_active && !peerlbl_active) |
| return NF_ACCEPT; |
| |
| sk = skb_to_full_sk(skb); |
| |
| #ifdef CONFIG_XFRM |
| /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec |
| * packet transformation so allow the packet to pass without any checks |
| * since we'll have another chance to perform access control checks |
| * when the packet is on it's final way out. |
| * NOTE: there appear to be some IPv6 multicast cases where skb->dst |
| * is NULL, in this case go ahead and apply access control. |
| * NOTE: if this is a local socket (skb->sk != NULL) that is in the |
| * TCP listening state we cannot wait until the XFRM processing |
| * is done as we will miss out on the SA label if we do; |
| * unfortunately, this means more work, but it is only once per |
| * connection. */ |
| if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && |
| !(sk && sk_listener(sk))) |
| return NF_ACCEPT; |
| #endif |
| |
| family = state->pf; |
| if (sk == NULL) { |
| /* Without an associated socket the packet is either coming |
| * from the kernel or it is being forwarded; check the packet |
| * to determine which and if the packet is being forwarded |
| * query the packet directly to determine the security label. */ |
| if (skb->skb_iif) { |
| secmark_perm = PACKET__FORWARD_OUT; |
| if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) |
| return NF_DROP; |
| } else { |
| secmark_perm = PACKET__SEND; |
| peer_sid = SECINITSID_KERNEL; |
| } |
| } else if (sk_listener(sk)) { |
| /* Locally generated packet but the associated socket is in the |
| * listening state which means this is a SYN-ACK packet. In |
| * this particular case the correct security label is assigned |
| * to the connection/request_sock but unfortunately we can't |
| * query the request_sock as it isn't queued on the parent |
| * socket until after the SYN-ACK packet is sent; the only |
| * viable choice is to regenerate the label like we do in |
| * selinux_inet_conn_request(). See also selinux_ip_output() |
| * for similar problems. */ |
| u32 skb_sid; |
| struct sk_security_struct *sksec; |
| |
| sksec = sk->sk_security; |
| if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) |
| return NF_DROP; |
| /* At this point, if the returned skb peerlbl is SECSID_NULL |
| * and the packet has been through at least one XFRM |
| * transformation then we must be dealing with the "final" |
| * form of labeled IPsec packet; since we've already applied |
| * all of our access controls on this packet we can safely |
| * pass the packet. */ |
| if (skb_sid == SECSID_NULL) { |
| switch (family) { |
| case PF_INET: |
| if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) |
| return NF_ACCEPT; |
| break; |
| case PF_INET6: |
| if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) |
| return NF_ACCEPT; |
| break; |
| default: |
| return NF_DROP_ERR(-ECONNREFUSED); |
| } |
| } |
| if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) |
| return NF_DROP; |
| secmark_perm = PACKET__SEND; |
| } else { |
| /* Locally generated packet, fetch the security label from the |
| * associated socket. */ |
| struct sk_security_struct *sksec = sk->sk_security; |
| peer_sid = sksec->sid; |
| secmark_perm = PACKET__SEND; |
| } |
| |
| ifindex = state->out->ifindex; |
| ad_net_init_from_iif(&ad, &net, ifindex, family); |
| if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) |
| return NF_DROP; |
| |
| if (secmark_active) |
| if (avc_has_perm(peer_sid, skb->secmark, |
| SECCLASS_PACKET, secmark_perm, &ad)) |
| return NF_DROP_ERR(-ECONNREFUSED); |
| |
| if (peerlbl_active) { |
| u32 if_sid; |
| u32 node_sid; |
| |
| if (sel_netif_sid(state->net, ifindex, &if_sid)) |
| return NF_DROP; |
| if (avc_has_perm(peer_sid, if_sid, |
| SECCLASS_NETIF, NETIF__EGRESS, &ad)) |
| return NF_DROP_ERR(-ECONNREFUSED); |
| |
| if (sel_netnode_sid(addrp, family, &node_sid)) |
| return NF_DROP; |
| if (avc_has_perm(peer_sid, node_sid, |
| SECCLASS_NODE, NODE__SENDTO, &ad)) |
| return NF_DROP_ERR(-ECONNREFUSED); |
| } |
| |
| return NF_ACCEPT; |
| } |
| #endif /* CONFIG_NETFILTER */ |
| |
| static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) |
| { |
| int rc = 0; |
| unsigned int msg_len; |
| unsigned int data_len = skb->len; |
| unsigned char *data = skb->data; |
| struct nlmsghdr *nlh; |
| struct sk_security_struct *sksec = sk->sk_security; |
| u16 sclass = sksec->sclass; |
| u32 perm; |
| |
| while (data_len >= nlmsg_total_size(0)) { |
| nlh = (struct nlmsghdr *)data; |
| |
| /* NOTE: the nlmsg_len field isn't reliably set by some netlink |
| * users which means we can't reject skb's with bogus |
| * length fields; our solution is to follow what |
| * netlink_rcv_skb() does and simply skip processing at |
| * messages with length fields that are clearly junk |
| */ |
| if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) |
| return 0; |
| |
| rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); |
| if (rc == 0) { |
| rc = sock_has_perm(sk, perm); |
| if (rc) |
| return rc; |
| } else if (rc == -EINVAL) { |
| /* -EINVAL is a missing msg/perm mapping */ |
| pr_warn_ratelimited("SELinux: unrecognized netlink" |
| " message: protocol=%hu nlmsg_type=%hu sclass=%s" |
| " pid=%d comm=%s\n", |
| sk->sk_protocol, nlh->nlmsg_type, |
| secclass_map[sclass - 1].name, |
| task_pid_nr(current), current->comm); |
| if (enforcing_enabled() && |
| !security_get_allow_unknown()) |
| return rc; |
| rc = 0; |
| } else if (rc == -ENOENT) { |
| /* -ENOENT is a missing socket/class mapping, ignore */ |
| rc = 0; |
| } else { |
| return rc; |
| } |
| |
| /* move to the next message after applying netlink padding */ |
| msg_len = NLMSG_ALIGN(nlh->nlmsg_len); |
| if (msg_len >= data_len) |
| return 0; |
| data_len -= msg_len; |
| data += msg_len; |
| } |
| |
| return rc; |
| } |
| |
| static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) |
| { |
| isec->sclass = sclass; |
| isec->sid = current_sid(); |
| } |
| |
| static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, |
| u32 perms) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(ipc_perms); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = ipc_perms->key; |
| |
| return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); |
| } |
| |
| static int selinux_msg_msg_alloc_security(struct msg_msg *msg) |
| { |
| struct msg_security_struct *msec; |
| |
| msec = selinux_msg_msg(msg); |
| msec->sid = SECINITSID_UNLABELED; |
| |
| return 0; |
| } |
| |
| /* message queue security operations */ |
| static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(msq); |
| ipc_init_security(isec, SECCLASS_MSGQ); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = msq->key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__CREATE, &ad); |
| } |
| |
| static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(msq); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = msq->key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__ASSOCIATE, &ad); |
| } |
| |
| static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) |
| { |
| u32 perms; |
| |
| switch (cmd) { |
| case IPC_INFO: |
| case MSG_INFO: |
| /* No specific object, just general system-wide information. */ |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); |
| case IPC_STAT: |
| case MSG_STAT: |
| case MSG_STAT_ANY: |
| perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; |
| break; |
| case IPC_SET: |
| perms = MSGQ__SETATTR; |
| break; |
| case IPC_RMID: |
| perms = MSGQ__DESTROY; |
| break; |
| default: |
| return 0; |
| } |
| |
| return ipc_has_perm(msq, perms); |
| } |
| |
| static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) |
| { |
| struct ipc_security_struct *isec; |
| struct msg_security_struct *msec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| int rc; |
| |
| isec = selinux_ipc(msq); |
| msec = selinux_msg_msg(msg); |
| |
| /* |
| * First time through, need to assign label to the message |
| */ |
| if (msec->sid == SECINITSID_UNLABELED) { |
| /* |
| * Compute new sid based on current process and |
| * message queue this message will be stored in |
| */ |
| rc = security_transition_sid(sid, isec->sid, |
| SECCLASS_MSG, NULL, &msec->sid); |
| if (rc) |
| return rc; |
| } |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = msq->key; |
| |
| /* Can this process write to the queue? */ |
| rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__WRITE, &ad); |
| if (!rc) |
| /* Can this process send the message */ |
| rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, |
| MSG__SEND, &ad); |
| if (!rc) |
| /* Can the message be put in the queue? */ |
| rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__ENQUEUE, &ad); |
| |
| return rc; |
| } |
| |
| static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, |
| struct task_struct *target, |
| long type, int mode) |
| { |
| struct ipc_security_struct *isec; |
| struct msg_security_struct *msec; |
| struct common_audit_data ad; |
| u32 sid = task_sid_obj(target); |
| int rc; |
| |
| isec = selinux_ipc(msq); |
| msec = selinux_msg_msg(msg); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = msq->key; |
| |
| rc = avc_has_perm(sid, isec->sid, |
| SECCLASS_MSGQ, MSGQ__READ, &ad); |
| if (!rc) |
| rc = avc_has_perm(sid, msec->sid, |
| SECCLASS_MSG, MSG__RECEIVE, &ad); |
| return rc; |
| } |
| |
| /* Shared Memory security operations */ |
| static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(shp); |
| ipc_init_security(isec, SECCLASS_SHM); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = shp->key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_SHM, |
| SHM__CREATE, &ad); |
| } |
| |
| static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(shp); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = shp->key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_SHM, |
| SHM__ASSOCIATE, &ad); |
| } |
| |
| /* Note, at this point, shp is locked down */ |
| static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) |
| { |
| u32 perms; |
| |
| switch (cmd) { |
| case IPC_INFO: |
| case SHM_INFO: |
| /* No specific object, just general system-wide information. */ |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); |
| case IPC_STAT: |
| case SHM_STAT: |
| case SHM_STAT_ANY: |
| perms = SHM__GETATTR | SHM__ASSOCIATE; |
| break; |
| case IPC_SET: |
| perms = SHM__SETATTR; |
| break; |
| case SHM_LOCK: |
| case SHM_UNLOCK: |
| perms = SHM__LOCK; |
| break; |
| case IPC_RMID: |
| perms = SHM__DESTROY; |
| break; |
| default: |
| return 0; |
| } |
| |
| return ipc_has_perm(shp, perms); |
| } |
| |
| static int selinux_shm_shmat(struct kern_ipc_perm *shp, |
| char __user *shmaddr, int shmflg) |
| { |
| u32 perms; |
| |
| if (shmflg & SHM_RDONLY) |
| perms = SHM__READ; |
| else |
| perms = SHM__READ | SHM__WRITE; |
| |
| return ipc_has_perm(shp, perms); |
| } |
| |
| /* Semaphore security operations */ |
| static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(sma); |
| ipc_init_security(isec, SECCLASS_SEM); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = sma->key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_SEM, |
| SEM__CREATE, &ad); |
| } |
| |
| static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = selinux_ipc(sma); |
| |
| ad.type = LSM_AUDIT_DATA_IPC; |
| ad.u.ipc_id = sma->key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_SEM, |
| SEM__ASSOCIATE, &ad); |
| } |
| |
| /* Note, at this point, sma is locked down */ |
| static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) |
| { |
| int err; |
| u32 perms; |
| |
| switch (cmd) { |
| case IPC_INFO: |
| case SEM_INFO: |
| /* No specific object, just general system-wide information. */ |
| return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); |
| case GETPID: |
| case GETNCNT: |
| case GETZCNT: |
| perms = SEM__GETATTR; |
| break; |
| case GETVAL: |
| case GETALL: |
| perms = SEM__READ; |
| break; |
| case SETVAL: |
| case SETALL: |
| perms = SEM__WRITE; |
| break; |
| case IPC_RMID: |
| perms = SEM__DESTROY; |
| break; |
| case IPC_SET: |
| perms = SEM__SETATTR; |
| break; |
| case IPC_STAT: |
| case SEM_STAT: |
| case SEM_STAT_ANY: |
| perms = SEM__GETATTR | SEM__ASSOCIATE; |
| break; |
| default: |
| return 0; |
| } |
| |
| err = ipc_has_perm(sma, perms); |
| return err; |
| } |
| |
| static int selinux_sem_semop(struct kern_ipc_perm *sma, |
| struct sembuf *sops, unsigned nsops, int alter) |
| { |
| u32 perms; |
| |
| if (alter) |
| perms = SEM__READ | SEM__WRITE; |
| else |
| perms = SEM__READ; |
| |
| return ipc_has_perm(sma, perms); |
| } |
| |
| static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) |
| { |
| u32 av = 0; |
| |
| av = 0; |
| if (flag & S_IRUGO) |
| av |= IPC__UNIX_READ; |
| if (flag & S_IWUGO) |
| av |= IPC__UNIX_WRITE; |
| |
| if (av == 0) |
| return 0; |
| |
| return ipc_has_perm(ipcp, av); |
| } |
| |
| static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) |
| { |
| struct ipc_security_struct *isec = selinux_ipc(ipcp); |
| *secid = isec->sid; |
| } |
| |
| static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) |
| { |
| if (inode) |
| inode_doinit_with_dentry(inode, dentry); |
| } |
| |
| static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p, |
| char **value) |
| { |
| const struct task_security_struct *tsec; |
| int error; |
| u32 sid; |
| u32 len; |
| |
| rcu_read_lock(); |
| tsec = selinux_cred(__task_cred(p)); |
| if (p != current) { |
| error = avc_has_perm(current_sid(), tsec->sid, |
| SECCLASS_PROCESS, PROCESS__GETATTR, NULL); |
| if (error) |
| goto err_unlock; |
| } |
| switch (attr) { |
| case LSM_ATTR_CURRENT: |
| sid = tsec->sid; |
| break; |
| case LSM_ATTR_PREV: |
| sid = tsec->osid; |
| break; |
| case LSM_ATTR_EXEC: |
| sid = tsec->exec_sid; |
| break; |
| case LSM_ATTR_FSCREATE: |
| sid = tsec->create_sid; |
| break; |
| case LSM_ATTR_KEYCREATE: |
| sid = tsec->keycreate_sid; |
| break; |
| case LSM_ATTR_SOCKCREATE: |
| sid = tsec->sockcreate_sid; |
| break; |
| default: |
| error = -EOPNOTSUPP; |
| goto err_unlock; |
| } |
| rcu_read_unlock(); |
| |
| if (sid == SECSID_NULL) { |
| *value = NULL; |
| return 0; |
| } |
| |
| error = security_sid_to_context(sid, value, &len); |
| if (error) |
| return error; |
| return len; |
| |
| err_unlock: |
| rcu_read_unlock(); |
| return error; |
| } |
| |
| static int selinux_lsm_setattr(u64 attr, void *value, size_t size) |
| { |
| struct task_security_struct *tsec; |
| struct cred *new; |
| u32 mysid = current_sid(), sid = 0, ptsid; |
| int error; |
| char *str = value; |
| |
| /* |
| * Basic control over ability to set these attributes at all. |
| */ |
| switch (attr) { |
| case LSM_ATTR_EXEC: |
| error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
| PROCESS__SETEXEC, NULL); |
| break; |
| case LSM_ATTR_FSCREATE: |
| error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
| PROCESS__SETFSCREATE, NULL); |
| break; |
| case LSM_ATTR_KEYCREATE: |
| error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
| PROCESS__SETKEYCREATE, NULL); |
| break; |
| case LSM_ATTR_SOCKCREATE: |
| error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
| PROCESS__SETSOCKCREATE, NULL); |
| break; |
| case LSM_ATTR_CURRENT: |
| error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
| PROCESS__SETCURRENT, NULL); |
| break; |
| default: |
| error = -EOPNOTSUPP; |
| break; |
| } |
| if (error) |
| return error; |
| |
| /* Obtain a SID for the context, if one was specified. */ |
| if (size && str[0] && str[0] != '\n') { |
| if (str[size-1] == '\n') { |
| str[size-1] = 0; |
| size--; |
| } |
| error = security_context_to_sid(value, size, |
| &sid, GFP_KERNEL); |
| if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) { |
| if (!has_cap_mac_admin(true)) { |
| struct audit_buffer *ab; |
| size_t audit_size; |
| |
| /* We strip a nul only if it is at the end, |
| * otherwise the context contains a nul and |
| * we should audit that */ |
| if (str[size - 1] == '\0') |
| audit_size = size - 1; |
| else |
| audit_size = size; |
| ab = audit_log_start(audit_context(), |
| GFP_ATOMIC, |
| AUDIT_SELINUX_ERR); |
| if (!ab) |
| return error; |
| audit_log_format(ab, "op=fscreate invalid_context="); |
| audit_log_n_untrustedstring(ab, value, |
| audit_size); |
| audit_log_end(ab); |
| |
| return error; |
| } |
| error = security_context_to_sid_force(value, size, |
| &sid); |
| } |
| if (error) |
| return error; |
| } |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| |
| /* Permission checking based on the specified context is |
| performed during the actual operation (execve, |
| open/mkdir/...), when we know the full context of the |
| operation. See selinux_bprm_creds_for_exec for the execve |
| checks and may_create for the file creation checks. The |
| operation will then fail if the context is not permitted. */ |
| tsec = selinux_cred(new); |
| if (attr == LSM_ATTR_EXEC) { |
| tsec->exec_sid = sid; |
| } else if (attr == LSM_ATTR_FSCREATE) { |
| tsec->create_sid = sid; |
| } else if (attr == LSM_ATTR_KEYCREATE) { |
| if (sid) { |
| error = avc_has_perm(mysid, sid, |
| SECCLASS_KEY, KEY__CREATE, NULL); |
| if (error) |
| goto abort_change; |
| } |
| tsec->keycreate_sid = sid; |
| } else if (attr == LSM_ATTR_SOCKCREATE) { |
| tsec->sockcreate_sid = sid; |
| } else if (attr == LSM_ATTR_CURRENT) { |
| error = -EINVAL; |
| if (sid == 0) |
| goto abort_change; |
| |
| if (!current_is_single_threaded()) { |
| error = security_bounded_transition(tsec->sid, sid); |
| if (error) |
| goto abort_change; |
| } |
| |
| /* Check permissions for the transition. */ |
| error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, |
| PROCESS__DYNTRANSITION, NULL); |
| if (error) |
| goto abort_change; |
| |
| /* Check for ptracing, and update the task SID if ok. |
| Otherwise, leave SID unchanged and fail. */ |
| ptsid = ptrace_parent_sid(); |
| if (ptsid != 0) { |
| error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, |
| PROCESS__PTRACE, NULL); |
| if (error) |
| goto abort_change; |
| } |
| |
| tsec->sid = sid; |
| } else { |
| error = -EINVAL; |
| goto abort_change; |
| } |
| |
| commit_creds(new); |
| return size; |
| |
| abort_change: |
| abort_creds(new); |
| return error; |
| } |
| |
| /** |
| * selinux_getselfattr - Get SELinux current task attributes |
| * @attr: the requested attribute |
| * @ctx: buffer to receive the result |
| * @size: buffer size (input), buffer size used (output) |
| * @flags: unused |
| * |
| * Fill the passed user space @ctx with the details of the requested |
| * attribute. |
| * |
| * Returns the number of attributes on success, an error code otherwise. |
| * There will only ever be one attribute. |
| */ |
| static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, |
| u32 *size, u32 flags) |
| { |
| int rc; |
| char *val = NULL; |
| int val_len; |
| |
| val_len = selinux_lsm_getattr(attr, current, &val); |
| if (val_len < 0) |
| return val_len; |
| rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); |
| kfree(val); |
| return (!rc ? 1 : rc); |
| } |
| |
| static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, |
| u32 size, u32 flags) |
| { |
| int rc; |
| |
| rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len); |
| if (rc > 0) |
| return 0; |
| return rc; |
| } |
| |
| static int selinux_getprocattr(struct task_struct *p, |
| const char *name, char **value) |
| { |
| unsigned int attr = lsm_name_to_attr(name); |
| int rc; |
| |
| if (attr) { |
| rc = selinux_lsm_getattr(attr, p, value); |
| if (rc != -EOPNOTSUPP) |
| return rc; |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int selinux_setprocattr(const char *name, void *value, size_t size) |
| { |
| int attr = lsm_name_to_attr(name); |
| |
| if (attr) |
| return selinux_lsm_setattr(attr, value, size); |
| return -EINVAL; |
| } |
| |
| static int selinux_ismaclabel(const char *name) |
| { |
| return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); |
| } |
| |
| static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) |
| { |
| return security_sid_to_context(secid, |
| secdata, seclen); |
| } |
| |
| static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) |
| { |
| return security_context_to_sid(secdata, seclen, |
| secid, GFP_KERNEL); |
| } |
| |
| static void selinux_release_secctx(char *secdata, u32 seclen) |
| { |
| kfree(secdata); |
| } |
| |
| static void selinux_inode_invalidate_secctx(struct inode *inode) |
| { |
| struct inode_security_struct *isec = selinux_inode(inode); |
| |
| spin_lock(&isec->lock); |
| isec->initialized = LABEL_INVALID; |
| spin_unlock(&isec->lock); |
| } |
| |
| /* |
| * called with inode->i_mutex locked |
| */ |
| static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) |
| { |
| int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, |
| ctx, ctxlen, 0); |
| /* Do not return error when suppressing label (SBLABEL_MNT not set). */ |
| return rc == -EOPNOTSUPP ? 0 : rc; |
| } |
| |
| /* |
| * called with inode->i_mutex locked |
| */ |
| static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) |
| { |
| return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, |
| ctx, ctxlen, 0); |
| } |
| |
| static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) |
| { |
| int len = 0; |
| len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, |
| XATTR_SELINUX_SUFFIX, ctx, true); |
| if (len < 0) |
| return len; |
| *ctxlen = len; |
| return 0; |
| } |
| #ifdef CONFIG_KEYS |
| |
| static int selinux_key_alloc(struct key *k, const struct cred *cred, |
| unsigned long flags) |
| { |
| const struct task_security_struct *tsec; |
| struct key_security_struct *ksec; |
| |
| ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); |
| if (!ksec) |
| return -ENOMEM; |
| |
| tsec = selinux_cred(cred); |
| if (tsec->keycreate_sid) |
| ksec->sid = tsec->keycreate_sid; |
| else |
| ksec->sid = tsec->sid; |
| |
| k->security = ksec; |
| return 0; |
| } |
| |
| static void selinux_key_free(struct key *k) |
| { |
| struct key_security_struct *ksec = k->security; |
| |
| k->security = NULL; |
| kfree(ksec); |
| } |
| |
| static int selinux_key_permission(key_ref_t key_ref, |
| const struct cred *cred, |
| enum key_need_perm need_perm) |
| { |
| struct key *key; |
| struct key_security_struct *ksec; |
| u32 perm, sid; |
| |
| switch (need_perm) { |
| case KEY_NEED_VIEW: |
| perm = KEY__VIEW; |
| break; |
| case KEY_NEED_READ: |
| perm = KEY__READ; |
| break; |
| case KEY_NEED_WRITE: |
| perm = KEY__WRITE; |
| break; |
| case KEY_NEED_SEARCH: |
| perm = KEY__SEARCH; |
| break; |
| case KEY_NEED_LINK: |
| perm = KEY__LINK; |
| break; |
| case KEY_NEED_SETATTR: |
| perm = KEY__SETATTR; |
| break; |
| case KEY_NEED_UNLINK: |
| case KEY_SYSADMIN_OVERRIDE: |
| case KEY_AUTHTOKEN_OVERRIDE: |
| case KEY_DEFER_PERM_CHECK: |
| return 0; |
| default: |
| WARN_ON(1); |
| return -EPERM; |
| |
| } |
| |
| sid = cred_sid(cred); |
| key = key_ref_to_ptr(key_ref); |
| ksec = key->security; |
| |
| return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); |
| } |
| |
| static int selinux_key_getsecurity(struct key *key, char **_buffer) |
| { |
| struct key_security_struct *ksec = key->security; |
| char *context = NULL; |
| unsigned len; |
| int rc; |
| |
| rc = security_sid_to_context(ksec->sid, |
| &context, &len); |
| if (!rc) |
| rc = len; |
| *_buffer = context; |
| return rc; |
| } |
| |
| #ifdef CONFIG_KEY_NOTIFICATIONS |
| static int selinux_watch_key(struct key *key) |
| { |
| struct key_security_struct *ksec = key->security; |
| u32 sid = current_sid(); |
| |
| return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); |
| } |
| #endif |
| #endif |
| |
| #ifdef CONFIG_SECURITY_INFINIBAND |
| static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) |
| { |
| struct common_audit_data ad; |
| int err; |
| u32 sid = 0; |
| struct ib_security_struct *sec = ib_sec; |
| struct lsm_ibpkey_audit ibpkey; |
| |
| err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); |
| if (err) |
| return err; |
| |
| ad.type = LSM_AUDIT_DATA_IBPKEY; |
| ibpkey.subnet_prefix = subnet_prefix; |
| ibpkey.pkey = pkey_val; |
| ad.u.ibpkey = &ibpkey; |
| return avc_has_perm(sec->sid, sid, |
| SECCLASS_INFINIBAND_PKEY, |
| INFINIBAND_PKEY__ACCESS, &ad); |
| } |
| |
| static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, |
| u8 port_num) |
| { |
| struct common_audit_data ad; |
| int err; |
| u32 sid = 0; |
| struct ib_security_struct *sec = ib_sec; |
| struct lsm_ibendport_audit ibendport; |
| |
| err = security_ib_endport_sid(dev_name, port_num, |
| &sid); |
| |
| if (err) |
| return err; |
| |
| ad.type = LSM_AUDIT_DATA_IBENDPORT; |
| ibendport.dev_name = dev_name; |
| ibendport.port = port_num; |
| ad.u.ibendport = &ibendport; |
| return avc_has_perm(sec->sid, sid, |
| SECCLASS_INFINIBAND_ENDPORT, |
| INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); |
| } |
| |
| static int selinux_ib_alloc_security(void **ib_sec) |
| { |
| struct ib_security_struct *sec; |
| |
| sec = kzalloc(sizeof(*sec), GFP_KERNEL); |
| if (!sec) |
| return -ENOMEM; |
| sec->sid = current_sid(); |
| |
| *ib_sec = sec; |
| return 0; |
| } |
| |
| static void selinux_ib_free_security(void *ib_sec) |
| { |
| kfree(ib_sec); |
| } |
| #endif |
| |
| #ifdef CONFIG_BPF_SYSCALL |
| static int selinux_bpf(int cmd, union bpf_attr *attr, |
| unsigned int size) |
| { |
| u32 sid = current_sid(); |
| int ret; |
| |
| switch (cmd) { |
| case BPF_MAP_CREATE: |
| ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, |
| NULL); |
| break; |
| case BPF_PROG_LOAD: |
| ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, |
| NULL); |
| break; |
| default: |
| ret = 0; |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static u32 bpf_map_fmode_to_av(fmode_t fmode) |
| { |
| u32 av = 0; |
| |
| if (fmode & FMODE_READ) |
| av |= BPF__MAP_READ; |
| if (fmode & FMODE_WRITE) |
| av |= BPF__MAP_WRITE; |
| return av; |
| } |
| |
| /* This function will check the file pass through unix socket or binder to see |
| * if it is a bpf related object. And apply corresponding checks on the bpf |
| * object based on the type. The bpf maps and programs, not like other files and |
| * socket, are using a shared anonymous inode inside the kernel as their inode. |
| * So checking that inode cannot identify if the process have privilege to |
| * access the bpf object and that's why we have to add this additional check in |
| * selinux_file_receive and selinux_binder_transfer_files. |
| */ |
| static int bpf_fd_pass(const struct file *file, u32 sid) |
| { |
| struct bpf_security_struct *bpfsec; |
| struct bpf_prog *prog; |
| struct bpf_map *map; |
| int ret; |
| |
| if (file->f_op == &bpf_map_fops) { |
| map = file->private_data; |
| bpfsec = map->security; |
| ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
| bpf_map_fmode_to_av(file->f_mode), NULL); |
| if (ret) |
| return ret; |
| } else if (file->f_op == &bpf_prog_fops) { |
| prog = file->private_data; |
| bpfsec = prog->aux->security; |
| ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
| BPF__PROG_RUN, NULL); |
| if (ret) |
| return ret; |
| } |
| return 0; |
| } |
| |
| static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) |
| { |
| u32 sid = current_sid(); |
| struct bpf_security_struct *bpfsec; |
| |
| bpfsec = map->security; |
| return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
| bpf_map_fmode_to_av(fmode), NULL); |
| } |
| |
| static int selinux_bpf_prog(struct bpf_prog *prog) |
| { |
| u32 sid = current_sid(); |
| struct bpf_security_struct *bpfsec; |
| |
| bpfsec = prog->aux->security; |
| return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
| BPF__PROG_RUN, NULL); |
| } |
| |
| static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, |
| struct bpf_token *token) |
| { |
| struct bpf_security_struct *bpfsec; |
| |
| bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); |
| if (!bpfsec) |
| return -ENOMEM; |
| |
| bpfsec->sid = current_sid(); |
| map->security = bpfsec; |
| |
| return 0; |
| } |
| |
| static void selinux_bpf_map_free(struct bpf_map *map) |
| { |
| struct bpf_security_struct *bpfsec = map->security; |
| |
| map->security = NULL; |
| kfree(bpfsec); |
| } |
| |
| static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, |
| struct bpf_token *token) |
| { |
| struct bpf_security_struct *bpfsec; |
| |
| bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); |
| if (!bpfsec) |
| return -ENOMEM; |
| |
| bpfsec->sid = current_sid(); |
| prog->aux->security = bpfsec; |
| |
| return 0; |
| } |
| |
| static void selinux_bpf_prog_free(struct bpf_prog *prog) |
| { |
| struct bpf_security_struct *bpfsec = prog->aux->security; |
| |
| prog->aux->security = NULL; |
| kfree(bpfsec); |
| } |
| |
| static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, |
| struct path *path) |
| { |
| struct bpf_security_struct *bpfsec; |
| |
| bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); |
| if (!bpfsec) |
| return -ENOMEM; |
| |
| bpfsec->sid = current_sid(); |
| token->security = bpfsec; |
| |
| return 0; |
| } |
| |
| static void selinux_bpf_token_free(struct bpf_token *token) |
| { |
| struct bpf_security_struct *bpfsec = token->security; |
| |
| token->security = NULL; |
| kfree(bpfsec); |
| } |
| #endif |
| |
| struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { |
| .lbs_cred = sizeof(struct task_security_struct), |
| .lbs_file = sizeof(struct file_security_struct), |
| .lbs_inode = sizeof(struct inode_security_struct), |
| .lbs_ipc = sizeof(struct ipc_security_struct), |
| .lbs_msg_msg = sizeof(struct msg_security_struct), |
| .lbs_superblock = sizeof(struct superblock_security_struct), |
| .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, |
| }; |
| |
| #ifdef CONFIG_PERF_EVENTS |
| static int selinux_perf_event_open(struct perf_event_attr *attr, int type) |
| { |
| u32 requested, sid = current_sid(); |
| |
| if (type == PERF_SECURITY_OPEN) |
| requested = PERF_EVENT__OPEN; |
| else if (type == PERF_SECURITY_CPU) |
| requested = PERF_EVENT__CPU; |
| else if (type == PERF_SECURITY_KERNEL) |
| requested = PERF_EVENT__KERNEL; |
| else if (type == PERF_SECURITY_TRACEPOINT) |
| requested = PERF_EVENT__TRACEPOINT; |
| else |
| return -EINVAL; |
| |
| return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, |
| requested, NULL); |
| } |
| |
| static int selinux_perf_event_alloc(struct perf_event *event) |
| { |
| struct perf_event_security_struct *perfsec; |
| |
| perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); |
| if (!perfsec) |
| return -ENOMEM; |
| |
| perfsec->sid = current_sid(); |
| event->security = perfsec; |
| |
| return 0; |
| } |
| |
| static void selinux_perf_event_free(struct perf_event *event) |
| { |
| struct perf_event_security_struct *perfsec = event->security; |
| |
| event->security = NULL; |
| kfree(perfsec); |
| } |
| |
| static int selinux_perf_event_read(struct perf_event *event) |
| { |
| struct perf_event_security_struct *perfsec = event->security; |
| u32 sid = current_sid(); |
| |
| return avc_has_perm(sid, perfsec->sid, |
| SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); |
| } |
| |
| static int selinux_perf_event_write(struct perf_event *event) |
| { |
| struct perf_event_security_struct *perfsec = event->security; |
| u32 sid = current_sid(); |
| |
| return avc_has_perm(sid, perfsec->sid, |
| SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); |
| } |
| #endif |
| |
| #ifdef CONFIG_IO_URING |
| /** |
| * selinux_uring_override_creds - check the requested cred override |
| * @new: the target creds |
| * |
| * Check to see if the current task is allowed to override it's credentials |
| * to service an io_uring operation. |
| */ |
| static int selinux_uring_override_creds(const struct cred *new) |
| { |
| return avc_has_perm(current_sid(), cred_sid(new), |
| SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); |
| } |
| |
| /** |
| * selinux_uring_sqpoll - check if a io_uring polling thread can be created |
| * |
| * Check to see if the current task is allowed to create a new io_uring |
| * kernel polling thread. |
| */ |
| static int selinux_uring_sqpoll(void) |
| { |
| u32 sid = current_sid(); |
| |
| return avc_has_perm(sid, sid, |
| SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); |
| } |
| |
| /** |
| * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed |
| * @ioucmd: the io_uring command structure |
| * |
| * Check to see if the current domain is allowed to execute an |
| * IORING_OP_URING_CMD against the device/file specified in @ioucmd. |
| * |
| */ |
| static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) |
| { |
| struct file *file = ioucmd->file; |
| struct inode *inode = file_inode(file); |
| struct inode_security_struct *isec = selinux_inode(inode); |
| struct common_audit_data ad; |
| |
| ad.type = LSM_AUDIT_DATA_FILE; |
| ad.u.file = file; |
| |
| return avc_has_perm(current_sid(), isec->sid, |
| SECCLASS_IO_URING, IO_URING__CMD, &ad); |
| } |
| #endif /* CONFIG_IO_URING */ |
| |
| static const struct lsm_id selinux_lsmid = { |
| .name = "selinux", |
| .id = LSM_ID_SELINUX, |
| }; |
| |
| /* |
| * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: |
| * 1. any hooks that don't belong to (2.) or (3.) below, |
| * 2. hooks that both access structures allocated by other hooks, and allocate |
| * structures that can be later accessed by other hooks (mostly "cloning" |
| * hooks), |
| * 3. hooks that only allocate structures that can be later accessed by other |
| * hooks ("allocating" hooks). |
| * |
| * Please follow block comment delimiters in the list to keep this order. |
| */ |
| static struct security_hook_list selinux_hooks[] __ro_after_init = { |
| LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), |
| LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), |
| LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), |
| LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), |
| |
| LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), |
| LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), |
| LSM_HOOK_INIT(capget, selinux_capget), |
| LSM_HOOK_INIT(capset, selinux_capset), |
| LSM_HOOK_INIT(capable, selinux_capable), |
| LSM_HOOK_INIT(quotactl, selinux_quotactl), |
| LSM_HOOK_INIT(quota_on, selinux_quota_on), |
| LSM_HOOK_INIT(syslog, selinux_syslog), |
| LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), |
| |
| LSM_HOOK_INIT(netlink_send, selinux_netlink_send), |
| |
| LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), |
| LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), |
| LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), |
| |
| LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), |
| LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), |
| LSM_HOOK_INIT(sb_remount, selinux_sb_remount), |
| LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), |
| LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), |
| LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), |
| LSM_HOOK_INIT(sb_mount, selinux_mount), |
| LSM_HOOK_INIT(sb_umount, selinux_umount), |
| LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), |
| LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), |
| |
| LSM_HOOK_INIT(move_mount, selinux_move_mount), |
| |
| LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), |
| LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), |
| |
| LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), |
| LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), |
| LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), |
| LSM_HOOK_INIT(inode_create, selinux_inode_create), |
| LSM_HOOK_INIT(inode_link, selinux_inode_link), |
| LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), |
| LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), |
| LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), |
| LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), |
| LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), |
| LSM_HOOK_INIT(inode_rename, selinux_inode_rename), |
| LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), |
| LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), |
| LSM_HOOK_INIT(inode_permission, selinux_inode_permission), |
| LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), |
| LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), |
| LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap), |
| LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), |
| LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), |
| LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), |
| LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), |
| LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), |
| LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), |
| LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), |
| LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), |
| LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), |
| LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), |
| LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), |
| LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), |
| LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), |
| LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), |
| LSM_HOOK_INIT(path_notify, selinux_path_notify), |
| |
| LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), |
| |
| LSM_HOOK_INIT(file_permission, selinux_file_permission), |
| LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), |
| LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), |
| LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), |
| LSM_HOOK_INIT(mmap_file, selinux_mmap_file), |
| LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), |
| LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), |
| LSM_HOOK_INIT(file_lock, selinux_file_lock), |
| LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), |
| LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), |
| LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), |
| LSM_HOOK_INIT(file_receive, selinux_file_receive), |
| |
| LSM_HOOK_INIT(file_open, selinux_file_open), |
| |
| LSM_HOOK_INIT(task_alloc, selinux_task_alloc), |
| LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), |
| LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), |
| LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), |
| LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), |
| LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), |
| LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), |
| LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), |
| LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), |
| LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), |
| LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), |
| LSM_HOOK_INIT(task_getsid, selinux_task_getsid), |
| LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), |
| LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), |
| LSM_HOOK_INIT(task_setnice, selinux_task_setnice), |
| LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), |
| LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), |
| LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), |
| LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), |
| LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), |
| LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), |
| LSM_HOOK_INIT(task_movememory, selinux_task_movememory), |
| LSM_HOOK_INIT(task_kill, selinux_task_kill), |
| LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), |
| LSM_HOOK_INIT(userns_create, selinux_userns_create), |
| |
| LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), |
| LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), |
| |
| LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), |
| LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), |
| LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), |
| LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), |
| |
| LSM_HOOK_INIT(shm_associate, selinux_shm_associate), |
| LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), |
| LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), |
| |
| LSM_HOOK_INIT(sem_associate, selinux_sem_associate), |
| LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), |
| LSM_HOOK_INIT(sem_semop, selinux_sem_semop), |
| |
| LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), |
| |
| LSM_HOOK_INIT(getselfattr, selinux_getselfattr), |
| LSM_HOOK_INIT(setselfattr, selinux_setselfattr), |
| LSM_HOOK_INIT(getprocattr, selinux_getprocattr), |
| LSM_HOOK_INIT(setprocattr, selinux_setprocattr), |
| |
| LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), |
| LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), |
| LSM_HOOK_INIT(release_secctx, selinux_release_secctx), |
| LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), |
| LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), |
| LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), |
| |
| LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), |
| LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), |
| |
| LSM_HOOK_INIT(socket_create, selinux_socket_create), |
| LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), |
| LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), |
| LSM_HOOK_INIT(socket_bind, selinux_socket_bind), |
| LSM_HOOK_INIT(socket_connect, selinux_socket_connect), |
| LSM_HOOK_INIT(socket_listen, selinux_socket_listen), |
| LSM_HOOK_INIT(socket_accept, selinux_socket_accept), |
| LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), |
| LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), |
| LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), |
| LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), |
| LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), |
| LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), |
| LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), |
| LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), |
| LSM_HOOK_INIT(socket_getpeersec_stream, |
| selinux_socket_getpeersec_stream), |
| LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), |
| LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), |
| LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), |
| LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), |
| LSM_HOOK_INIT(sock_graft, selinux_sock_graft), |
| LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), |
| LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), |
| LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), |
| LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), |
| LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), |
| LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), |
| LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), |
| LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), |
| LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), |
| LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), |
| LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), |
| LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), |
| LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), |
| LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), |
| LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), |
| LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), |
| LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), |
| #ifdef CONFIG_SECURITY_INFINIBAND |
| LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), |
| LSM_HOOK_INIT(ib_endport_manage_subnet, |
| selinux_ib_endport_manage_subnet), |
| LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), |
| #endif |
| #ifdef CONFIG_SECURITY_NETWORK_XFRM |
| LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), |
| LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), |
| LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), |
| LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), |
| LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), |
| LSM_HOOK_INIT(xfrm_state_pol_flow_match, |
| selinux_xfrm_state_pol_flow_match), |
| LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), |
| #endif |
| |
| #ifdef CONFIG_KEYS |
| LSM_HOOK_INIT(key_free, selinux_key_free), |
| LSM_HOOK_INIT(key_permission, selinux_key_permission), |
| LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), |
| #ifdef CONFIG_KEY_NOTIFICATIONS |
| LSM_HOOK_INIT(watch_key, selinux_watch_key), |
| #endif |
| #endif |
| |
| #ifdef CONFIG_AUDIT |
| LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), |
| LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), |
| LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), |
| #endif |
| |
| #ifdef CONFIG_BPF_SYSCALL |
| LSM_HOOK_INIT(bpf, selinux_bpf), |
| LSM_HOOK_INIT(bpf_map, selinux_bpf_map), |
| LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), |
| LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), |
| LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), |
| LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), |
| #endif |
| |
| #ifdef CONFIG_PERF_EVENTS |
| LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), |
| LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), |
| LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), |
| LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), |
| #endif |
| |
| #ifdef CONFIG_IO_URING |
| LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), |
| LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), |
| LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), |
| #endif |
| |
| /* |
| * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE |
| */ |
| LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), |
| LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), |
| LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), |
| LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), |
| #ifdef CONFIG_SECURITY_NETWORK_XFRM |
| LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), |
| #endif |
| |
| /* |
| * PUT "ALLOCATING" HOOKS HERE |
| */ |
| LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), |
| LSM_HOOK_INIT(msg_queue_alloc_security, |
| selinux_msg_queue_alloc_security), |
| LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), |
| LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), |
| LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), |
| LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), |
| LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), |
| LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), |
| LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), |
| LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), |
| #ifdef CONFIG_SECURITY_INFINIBAND |
| LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), |
| #endif |
| #ifdef CONFIG_SECURITY_NETWORK_XFRM |
| LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), |
| LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), |
| LSM_HOOK_INIT(xfrm_state_alloc_acquire, |
| selinux_xfrm_state_alloc_acquire), |
| #endif |
| #ifdef CONFIG_KEYS |
| LSM_HOOK_INIT(key_alloc, selinux_key_alloc), |
| #endif |
| #ifdef CONFIG_AUDIT |
| LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), |
| #endif |
| #ifdef CONFIG_BPF_SYSCALL |
| LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), |
| LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), |
| LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), |
| #endif |
| #ifdef CONFIG_PERF_EVENTS |
| LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), |
| #endif |
| }; |
| |
| static __init int selinux_init(void) |
| { |
| pr_info("SELinux: Initializing.\n"); |
| |
| memset(&selinux_state, 0, sizeof(selinux_state)); |
| enforcing_set(selinux_enforcing_boot); |
| selinux_avc_init(); |
| mutex_init(&selinux_state.status_lock); |
| mutex_init(&selinux_state.policy_mutex); |
| |
| /* Set the security state for the initial task. */ |
| cred_init_security(); |
| |
| default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); |
| if (!default_noexec) |
| pr_notice("SELinux: virtual memory is executable by default\n"); |
| |
| avc_init(); |
| |
| avtab_cache_init(); |
| |
| ebitmap_cache_init(); |
| |
| hashtab_cache_init(); |
| |
| security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), |
| &selinux_lsmid); |
| |
| if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) |
| panic("SELinux: Unable to register AVC netcache callback\n"); |
| |
| if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) |
| panic("SELinux: Unable to register AVC LSM notifier callback\n"); |
| |
| if (selinux_enforcing_boot) |
| pr_debug("SELinux: Starting in enforcing mode\n"); |
| else |
| pr_debug("SELinux: Starting in permissive mode\n"); |
| |
| fs_validate_description("selinux", selinux_fs_parameters); |
| |
| return 0; |
| } |
| |
| static void delayed_superblock_init(struct super_block *sb, void *unused) |
| { |
| selinux_set_mnt_opts(sb, NULL, 0, NULL); |
| } |
| |
| void selinux_complete_init(void) |
| { |
| pr_debug("SELinux: Completing initialization.\n"); |
| |
| /* Set up any superblocks initialized prior to the policy load. */ |
| pr_debug("SELinux: Setting up existing superblocks.\n"); |
| iterate_supers(delayed_superblock_init, NULL); |
| } |
| |
| /* SELinux requires early initialization in order to label |
| all processes and objects when they are created. */ |
| DEFINE_LSM(selinux) = { |
| .name = "selinux", |
| .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, |
| .enabled = &selinux_enabled_boot, |
| .blobs = &selinux_blob_sizes, |
| .init = selinux_init, |
| }; |
| |
| #if defined(CONFIG_NETFILTER) |
| static const struct nf_hook_ops selinux_nf_ops[] = { |
| { |
| .hook = selinux_ip_postroute, |
| .pf = NFPROTO_IPV4, |
| .hooknum = NF_INET_POST_ROUTING, |
| .priority = NF_IP_PRI_SELINUX_LAST, |
| }, |
| { |
| .hook = selinux_ip_forward, |
| .pf = NFPROTO_IPV4, |
| .hooknum = NF_INET_FORWARD, |
| .priority = NF_IP_PRI_SELINUX_FIRST, |
| }, |
| { |
| .hook = selinux_ip_output, |
| .pf = NFPROTO_IPV4, |
| .hooknum = NF_INET_LOCAL_OUT, |
| .priority = NF_IP_PRI_SELINUX_FIRST, |
| }, |
| #if IS_ENABLED(CONFIG_IPV6) |
| { |
| .hook = selinux_ip_postroute, |
| .pf = NFPROTO_IPV6, |
| .hooknum = NF_INET_POST_ROUTING, |
| .priority = NF_IP6_PRI_SELINUX_LAST, |
| }, |
| { |
| .hook = selinux_ip_forward, |
| .pf = NFPROTO_IPV6, |
| .hooknum = NF_INET_FORWARD, |
| .priority = NF_IP6_PRI_SELINUX_FIRST, |
| }, |
| { |
| .hook = selinux_ip_output, |
| .pf = NFPROTO_IPV6, |
| .hooknum = NF_INET_LOCAL_OUT, |
| .priority = NF_IP6_PRI_SELINUX_FIRST, |
| }, |
| #endif /* IPV6 */ |
| }; |
| |
| static int __net_init selinux_nf_register(struct net *net) |
| { |
| return nf_register_net_hooks(net, selinux_nf_ops, |
| ARRAY_SIZE(selinux_nf_ops)); |
| } |
| |
| static void __net_exit selinux_nf_unregister(struct net *net) |
| { |
| nf_unregister_net_hooks(net, selinux_nf_ops, |
| ARRAY_SIZE(selinux_nf_ops)); |
| } |
| |
| static struct pernet_operations selinux_net_ops = { |
| .init = selinux_nf_register, |
| .exit = selinux_nf_unregister, |
| }; |
| |
| static int __init selinux_nf_ip_init(void) |
| { |
| int err; |
| |
| if (!selinux_enabled_boot) |
| return 0; |
| |
| pr_debug("SELinux: Registering netfilter hooks\n"); |
| |
| err = register_pernet_subsys(&selinux_net_ops); |
| if (err) |
| panic("SELinux: register_pernet_subsys: error %d\n", err); |
| |
| return 0; |
| } |
| __initcall(selinux_nf_ip_init); |
| #endif /* CONFIG_NETFILTER */ |