Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
| 3 | * linux/ipc/shm.c |
| 4 | * Copyright (C) 1992, 1993 Krishna Balasubramanian |
| 5 | * Many improvements/fixes by Bruno Haible. |
| 6 | * Replaced `struct shm_desc' by `struct vm_area_struct', July 1994. |
| 7 | * Fixed the shm swap deallocation (shm_unuse()), August 1998 Andrea Arcangeli. |
| 8 | * |
| 9 | * /proc/sysvipc/shm support (c) 1999 Dragos Acostachioaie <dragos@iname.com> |
| 10 | * BIGMEM support, Andrea Arcangeli <andrea@suse.de> |
| 11 | * SMP thread shm, Jean-Luc Boyard <jean-luc.boyard@siemens.fr> |
| 12 | * HIGHMEM support, Ingo Molnar <mingo@redhat.com> |
| 13 | * Make shmmax, shmall, shmmni sysctl'able, Christoph Rohland <cr@sap.com> |
| 14 | * Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com> |
| 15 | * Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com> |
| 16 | * |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 17 | * support for audit of ipc object properties and permission changes |
| 18 | * Dustin Kirkland <dustin.kirkland@us.ibm.com> |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 19 | * |
| 20 | * namespaces support |
| 21 | * OpenVZ, SWsoft Inc. |
| 22 | * Pavel Emelianov <xemul@openvz.org> |
Davidlohr Bueso | c2c737a | 2013-09-11 14:26:23 -0700 | [diff] [blame] | 23 | * |
| 24 | * Better ipc lock (kern_ipc_perm.lock) handling |
| 25 | * Davidlohr Bueso <davidlohr.bueso@hp.com>, June 2013. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | */ |
| 27 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | #include <linux/slab.h> |
| 29 | #include <linux/mm.h> |
| 30 | #include <linux/hugetlb.h> |
| 31 | #include <linux/shm.h> |
| 32 | #include <linux/init.h> |
| 33 | #include <linux/file.h> |
| 34 | #include <linux/mman.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #include <linux/shmem_fs.h> |
| 36 | #include <linux/security.h> |
| 37 | #include <linux/syscalls.h> |
| 38 | #include <linux/audit.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 39 | #include <linux/capability.h> |
Stephen Rothwell | 7d87e14c | 2005-05-01 08:59:12 -0700 | [diff] [blame] | 40 | #include <linux/ptrace.h> |
Mike Waychison | 19b4946 | 2005-09-06 15:17:10 -0700 | [diff] [blame] | 41 | #include <linux/seq_file.h> |
Nadia Derbey | 3e148c7 | 2007-10-18 23:40:54 -0700 | [diff] [blame] | 42 | #include <linux/rwsem.h> |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 43 | #include <linux/nsproxy.h> |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 44 | #include <linux/mount.h> |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 45 | #include <linux/ipc_namespace.h> |
Stephen Rothwell | 7d87e14c | 2005-05-01 08:59:12 -0700 | [diff] [blame] | 46 | |
Paul McQuade | 7153e40 | 2014-06-06 14:37:37 -0700 | [diff] [blame] | 47 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | |
| 49 | #include "util.h" |
| 50 | |
Eric W. Biederman | a2e102c | 2018-03-22 21:34:44 -0500 | [diff] [blame] | 51 | struct shmid_kernel /* private to the kernel */ |
| 52 | { |
| 53 | struct kern_ipc_perm shm_perm; |
| 54 | struct file *shm_file; |
| 55 | unsigned long shm_nattch; |
| 56 | unsigned long shm_segsz; |
| 57 | time64_t shm_atim; |
| 58 | time64_t shm_dtim; |
| 59 | time64_t shm_ctim; |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 60 | struct pid *shm_cprid; |
| 61 | struct pid *shm_lprid; |
Eric W. Biederman | a2e102c | 2018-03-22 21:34:44 -0500 | [diff] [blame] | 62 | struct user_struct *mlock_user; |
| 63 | |
| 64 | /* The task created the shm object. NULL if the task is dead. */ |
| 65 | struct task_struct *shm_creator; |
| 66 | struct list_head shm_clist; /* list by creator */ |
| 67 | } __randomize_layout; |
| 68 | |
| 69 | /* shm_mode upper byte flags */ |
| 70 | #define SHM_DEST 01000 /* segment will be destroyed on last detach */ |
| 71 | #define SHM_LOCKED 02000 /* segment will not be swapped */ |
| 72 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 73 | struct shm_file_data { |
| 74 | int id; |
| 75 | struct ipc_namespace *ns; |
| 76 | struct file *file; |
| 77 | const struct vm_operations_struct *vm_ops; |
| 78 | }; |
| 79 | |
| 80 | #define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data)) |
| 81 | |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 82 | static const struct file_operations shm_file_operations; |
Alexey Dobriyan | f0f37e2f | 2009-09-27 22:29:37 +0400 | [diff] [blame] | 83 | static const struct vm_operations_struct shm_vm_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | |
Pierre Peiffer | ed2ddbf | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 85 | #define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS]) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 87 | #define shm_unlock(shp) \ |
| 88 | ipc_unlock(&(shp)->shm_perm) |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 89 | |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 90 | static int newseg(struct ipc_namespace *, struct ipc_params *); |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 91 | static void shm_open(struct vm_area_struct *vma); |
| 92 | static void shm_close(struct vm_area_struct *vma); |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 93 | static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | #ifdef CONFIG_PROC_FS |
Mike Waychison | 19b4946 | 2005-09-06 15:17:10 -0700 | [diff] [blame] | 95 | static int sysvipc_shm_proc_show(struct seq_file *s, void *it); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | #endif |
| 97 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 98 | int shm_init_ns(struct ipc_namespace *ns) |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 99 | { |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 100 | ns->shm_ctlmax = SHMMAX; |
| 101 | ns->shm_ctlall = SHMALL; |
| 102 | ns->shm_ctlmni = SHMMNI; |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 103 | ns->shm_rmid_forced = 0; |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 104 | ns->shm_tot = 0; |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 105 | return ipc_init_ids(&shm_ids(ns)); |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 106 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 108 | /* |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 109 | * Called with shm_ids.rwsem (writer) and the shp structure locked. |
| 110 | * Only shm_ids.rwsem remains locked on exit. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 111 | */ |
Pierre Peiffer | 01b8b07 | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 112 | static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 113 | { |
Pierre Peiffer | 01b8b07 | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 114 | struct shmid_kernel *shp; |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 115 | |
Pierre Peiffer | 01b8b07 | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 116 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); |
| 117 | |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 118 | if (shp->shm_nattch) { |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 119 | shp->shm_perm.mode |= SHM_DEST; |
| 120 | /* Do not find it any more */ |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 121 | ipc_set_key_private(&shm_ids(ns), &shp->shm_perm); |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 122 | shm_unlock(shp); |
| 123 | } else |
| 124 | shm_destroy(ns, shp); |
| 125 | } |
| 126 | |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 127 | #ifdef CONFIG_IPC_NS |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 128 | void shm_exit_ns(struct ipc_namespace *ns) |
| 129 | { |
Pierre Peiffer | 01b8b07 | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 130 | free_ipcs(ns, &shm_ids(ns), do_shm_rmid); |
Serge E. Hallyn | 7d6feeb | 2009-12-15 16:47:27 -0800 | [diff] [blame] | 131 | idr_destroy(&ns->ids[IPC_SHM_IDS].ipcs_idr); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 132 | rhashtable_destroy(&ns->ids[IPC_SHM_IDS].key_ht); |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 133 | } |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 134 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | |
Linus Torvalds | 140d0b2 | 2011-08-04 19:35:59 -1000 | [diff] [blame] | 136 | static int __init ipc_ns_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | { |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 138 | const int err = shm_init_ns(&init_ipc_ns); |
| 139 | WARN(err, "ipc: sysv shm_init_ns failed: %d\n", err); |
| 140 | return err; |
Linus Torvalds | 140d0b2 | 2011-08-04 19:35:59 -1000 | [diff] [blame] | 141 | } |
| 142 | |
| 143 | pure_initcall(ipc_ns_init); |
| 144 | |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 145 | void __init shm_init(void) |
Linus Torvalds | 140d0b2 | 2011-08-04 19:35:59 -1000 | [diff] [blame] | 146 | { |
Mike Waychison | 19b4946 | 2005-09-06 15:17:10 -0700 | [diff] [blame] | 147 | ipc_init_proc_interface("sysvipc/shm", |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 148 | #if BITS_PER_LONG <= 32 |
| 149 | " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n", |
| 150 | #else |
| 151 | " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n", |
| 152 | #endif |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 153 | IPC_SHM_IDS, sysvipc_shm_proc_show); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | } |
| 155 | |
Davidlohr Bueso | 8b8d52a | 2013-09-11 14:26:15 -0700 | [diff] [blame] | 156 | static inline struct shmid_kernel *shm_obtain_object(struct ipc_namespace *ns, int id) |
| 157 | { |
Davidlohr Bueso | 55b7ae5 | 2015-06-30 14:58:42 -0700 | [diff] [blame] | 158 | struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&shm_ids(ns), id); |
Davidlohr Bueso | 8b8d52a | 2013-09-11 14:26:15 -0700 | [diff] [blame] | 159 | |
| 160 | if (IS_ERR(ipcp)) |
| 161 | return ERR_CAST(ipcp); |
| 162 | |
| 163 | return container_of(ipcp, struct shmid_kernel, shm_perm); |
| 164 | } |
| 165 | |
| 166 | static inline struct shmid_kernel *shm_obtain_object_check(struct ipc_namespace *ns, int id) |
| 167 | { |
| 168 | struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&shm_ids(ns), id); |
| 169 | |
| 170 | if (IS_ERR(ipcp)) |
| 171 | return ERR_CAST(ipcp); |
| 172 | |
| 173 | return container_of(ipcp, struct shmid_kernel, shm_perm); |
| 174 | } |
| 175 | |
Nadia Derbey | 3e148c7 | 2007-10-18 23:40:54 -0700 | [diff] [blame] | 176 | /* |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 177 | * shm_lock_(check_) routines are called in the paths where the rwsem |
Nadia Derbey | 00c2bf8 | 2008-07-25 01:48:03 -0700 | [diff] [blame] | 178 | * is not necessarily held. |
Nadia Derbey | 3e148c7 | 2007-10-18 23:40:54 -0700 | [diff] [blame] | 179 | */ |
Nadia Derbey | 023a535 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 180 | static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | { |
Nadia Derbey | 03f02c7 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 182 | struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id); |
| 183 | |
Davidlohr Bueso | c5c8975 | 2015-06-30 14:58:36 -0700 | [diff] [blame] | 184 | /* |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 185 | * Callers of shm_lock() must validate the status of the returned ipc |
| 186 | * object pointer (as returned by ipc_lock()), and error out as |
| 187 | * appropriate. |
Davidlohr Bueso | c5c8975 | 2015-06-30 14:58:36 -0700 | [diff] [blame] | 188 | */ |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 189 | if (IS_ERR(ipcp)) |
| 190 | return (void *)ipcp; |
Nadia Derbey | 03f02c7 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 191 | return container_of(ipcp, struct shmid_kernel, shm_perm); |
Nadia Derbey | 023a535 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 192 | } |
| 193 | |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 194 | static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp) |
| 195 | { |
| 196 | rcu_read_lock(); |
Davidlohr Bueso | cf9d5d7 | 2013-07-08 16:01:11 -0700 | [diff] [blame] | 197 | ipc_lock_object(&ipcp->shm_perm); |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 198 | } |
| 199 | |
Davidlohr Bueso | 53dad6d | 2013-09-23 17:04:45 -0700 | [diff] [blame] | 200 | static void shm_rcu_free(struct rcu_head *head) |
| 201 | { |
Manfred Spraul | dba4cdd | 2017-07-12 14:34:41 -0700 | [diff] [blame] | 202 | struct kern_ipc_perm *ptr = container_of(head, struct kern_ipc_perm, |
| 203 | rcu); |
| 204 | struct shmid_kernel *shp = container_of(ptr, struct shmid_kernel, |
| 205 | shm_perm); |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 206 | security_shm_free(&shp->shm_perm); |
Kees Cook | 42e618f | 2017-07-12 14:35:25 -0700 | [diff] [blame] | 207 | kvfree(shp); |
Davidlohr Bueso | 53dad6d | 2013-09-23 17:04:45 -0700 | [diff] [blame] | 208 | } |
| 209 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 210 | static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | { |
Jack Miller | ab602f7 | 2014-08-08 14:23:19 -0700 | [diff] [blame] | 212 | list_del(&s->shm_clist); |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 213 | ipc_rmid(&shm_ids(ns), &s->shm_perm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | } |
| 215 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 217 | static int __shm_open(struct vm_area_struct *vma) |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 218 | { |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 219 | struct file *file = vma->vm_file; |
| 220 | struct shm_file_data *sfd = shm_file_data(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | struct shmid_kernel *shp; |
| 222 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 223 | shp = shm_lock(sfd->ns, sfd->id); |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 224 | |
| 225 | if (IS_ERR(shp)) |
| 226 | return PTR_ERR(shp); |
| 227 | |
Deepa Dinamani | 7ff2819 | 2017-08-02 19:51:14 -0700 | [diff] [blame] | 228 | shp->shm_atim = ktime_get_real_seconds(); |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 229 | ipc_update_pid(&shp->shm_lprid, task_tgid(current)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | shp->shm_nattch++; |
| 231 | shm_unlock(shp); |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 232 | return 0; |
| 233 | } |
| 234 | |
| 235 | /* This is called by fork, once for every shm attach. */ |
| 236 | static void shm_open(struct vm_area_struct *vma) |
| 237 | { |
| 238 | int err = __shm_open(vma); |
| 239 | /* |
| 240 | * We raced in the idr lookup or with shm_destroy(). |
| 241 | * Either way, the ID is busted. |
| 242 | */ |
| 243 | WARN_ON_ONCE(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | } |
| 245 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | /* |
| 247 | * shm_destroy - free the struct shmid_kernel |
| 248 | * |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 249 | * @ns: namespace |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | * @shp: struct to free |
| 251 | * |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 252 | * It has to be called with shp and shm_ids.rwsem (writer) locked, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | * but returns with shp unlocked and freed. |
| 254 | */ |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 255 | static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | { |
Greg Thelen | a399b29 | 2013-11-21 14:32:00 -0800 | [diff] [blame] | 257 | struct file *shm_file; |
| 258 | |
| 259 | shm_file = shp->shm_file; |
| 260 | shp->shm_file = NULL; |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 261 | ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 262 | shm_rmid(ns, shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | shm_unlock(shp); |
Greg Thelen | a399b29 | 2013-11-21 14:32:00 -0800 | [diff] [blame] | 264 | if (!is_file_hugepages(shm_file)) |
| 265 | shmem_lock(shm_file, 0, shp->mlock_user); |
Hugh Dickins | 353d5c3 | 2009-08-24 16:30:28 +0100 | [diff] [blame] | 266 | else if (shp->mlock_user) |
Dave Hansen | 07a46ed | 2014-12-12 16:58:22 -0800 | [diff] [blame] | 267 | user_shm_unlock(i_size_read(file_inode(shm_file)), |
| 268 | shp->mlock_user); |
Greg Thelen | a399b29 | 2013-11-21 14:32:00 -0800 | [diff] [blame] | 269 | fput(shm_file); |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 270 | ipc_update_pid(&shp->shm_cprid, NULL); |
| 271 | ipc_update_pid(&shp->shm_lprid, NULL); |
Manfred Spraul | dba4cdd | 2017-07-12 14:34:41 -0700 | [diff] [blame] | 272 | ipc_rcu_putref(&shp->shm_perm, shm_rcu_free); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | } |
| 274 | |
| 275 | /* |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 276 | * shm_may_destroy - identifies whether shm segment should be destroyed now |
| 277 | * |
| 278 | * Returns true if and only if there are no active users of the segment and |
| 279 | * one of the following is true: |
| 280 | * |
| 281 | * 1) shmctl(id, IPC_RMID, NULL) was called for this shp |
| 282 | * |
| 283 | * 2) sysctl kernel.shm_rmid_forced is set to 1. |
| 284 | */ |
| 285 | static bool shm_may_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp) |
| 286 | { |
| 287 | return (shp->shm_nattch == 0) && |
| 288 | (ns->shm_rmid_forced || |
| 289 | (shp->shm_perm.mode & SHM_DEST)); |
| 290 | } |
| 291 | |
| 292 | /* |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 293 | * remove the attach descriptor vma. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | * free memory for segment if it is marked destroyed. |
| 295 | * The descriptor has already been removed from the current->mm->mmap list |
| 296 | * and will later be kfree()d. |
| 297 | */ |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 298 | static void shm_close(struct vm_area_struct *vma) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | { |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 300 | struct file *file = vma->vm_file; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 301 | struct shm_file_data *sfd = shm_file_data(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | struct shmid_kernel *shp; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 303 | struct ipc_namespace *ns = sfd->ns; |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 304 | |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 305 | down_write(&shm_ids(ns).rwsem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | /* remove from the list of attaches of the shm segment */ |
Nadia Derbey | 00c2bf8 | 2008-07-25 01:48:03 -0700 | [diff] [blame] | 307 | shp = shm_lock(ns, sfd->id); |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 308 | |
| 309 | /* |
| 310 | * We raced in the idr lookup or with shm_destroy(). |
| 311 | * Either way, the ID is busted. |
| 312 | */ |
| 313 | if (WARN_ON_ONCE(IS_ERR(shp))) |
| 314 | goto done; /* no-op */ |
| 315 | |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 316 | ipc_update_pid(&shp->shm_lprid, task_tgid(current)); |
Deepa Dinamani | 7ff2819 | 2017-08-02 19:51:14 -0700 | [diff] [blame] | 317 | shp->shm_dtim = ktime_get_real_seconds(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | shp->shm_nattch--; |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 319 | if (shm_may_destroy(ns, shp)) |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 320 | shm_destroy(ns, shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | else |
| 322 | shm_unlock(shp); |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 323 | done: |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 324 | up_write(&shm_ids(ns).rwsem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | } |
| 326 | |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 327 | /* Called with ns->shm_ids(ns).rwsem locked */ |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 328 | static int shm_try_destroy_orphaned(int id, void *p, void *data) |
| 329 | { |
| 330 | struct ipc_namespace *ns = data; |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 331 | struct kern_ipc_perm *ipcp = p; |
| 332 | struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm); |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 333 | |
| 334 | /* |
| 335 | * We want to destroy segments without users and with already |
| 336 | * exit'ed originating process. |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 337 | * |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 338 | * As shp->* are changed under rwsem, it's safe to skip shp locking. |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 339 | */ |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 340 | if (shp->shm_creator != NULL) |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 341 | return 0; |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 342 | |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 343 | if (shm_may_destroy(ns, shp)) { |
| 344 | shm_lock_by_ptr(shp); |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 345 | shm_destroy(ns, shp); |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 346 | } |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 347 | return 0; |
| 348 | } |
| 349 | |
| 350 | void shm_destroy_orphaned(struct ipc_namespace *ns) |
| 351 | { |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 352 | down_write(&shm_ids(ns).rwsem); |
Vasiliy Kulikov | 33a30ed | 2011-08-03 22:26:55 +0400 | [diff] [blame] | 353 | if (shm_ids(ns).in_use) |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 354 | idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_orphaned, ns); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 355 | up_write(&shm_ids(ns).rwsem); |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 356 | } |
| 357 | |
Jack Miller | 83293c0f5 | 2014-08-08 14:23:21 -0700 | [diff] [blame] | 358 | /* Locking assumes this will only be called with task == current */ |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 359 | void exit_shm(struct task_struct *task) |
| 360 | { |
Vasiliy Kulikov | 4c677e2 | 2011-07-29 03:56:40 +0400 | [diff] [blame] | 361 | struct ipc_namespace *ns = task->nsproxy->ipc_ns; |
Jack Miller | ab602f7 | 2014-08-08 14:23:19 -0700 | [diff] [blame] | 362 | struct shmid_kernel *shp, *n; |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 363 | |
Jack Miller | 83293c0f5 | 2014-08-08 14:23:21 -0700 | [diff] [blame] | 364 | if (list_empty(&task->sysvshm.shm_clist)) |
Vasiliy Kulikov | 298507d | 2011-08-03 22:28:26 +0400 | [diff] [blame] | 365 | return; |
| 366 | |
Jack Miller | 83293c0f5 | 2014-08-08 14:23:21 -0700 | [diff] [blame] | 367 | /* |
| 368 | * If kernel.shm_rmid_forced is not set then only keep track of |
| 369 | * which shmids are orphaned, so that a later set of the sysctl |
| 370 | * can clean them up. |
| 371 | */ |
| 372 | if (!ns->shm_rmid_forced) { |
| 373 | down_read(&shm_ids(ns).rwsem); |
| 374 | list_for_each_entry(shp, &task->sysvshm.shm_clist, shm_clist) |
| 375 | shp->shm_creator = NULL; |
| 376 | /* |
| 377 | * Only under read lock but we are only called on current |
| 378 | * so no entry on the list will be shared. |
| 379 | */ |
| 380 | list_del(&task->sysvshm.shm_clist); |
| 381 | up_read(&shm_ids(ns).rwsem); |
| 382 | return; |
| 383 | } |
| 384 | |
| 385 | /* |
| 386 | * Destroy all already created segments, that were not yet mapped, |
| 387 | * and mark any mapped as orphan to cover the sysctl toggling. |
| 388 | * Destroy is skipped if shm_may_destroy() returns false. |
| 389 | */ |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 390 | down_write(&shm_ids(ns).rwsem); |
Jack Miller | 83293c0f5 | 2014-08-08 14:23:21 -0700 | [diff] [blame] | 391 | list_for_each_entry_safe(shp, n, &task->sysvshm.shm_clist, shm_clist) { |
| 392 | shp->shm_creator = NULL; |
| 393 | |
| 394 | if (shm_may_destroy(ns, shp)) { |
| 395 | shm_lock_by_ptr(shp); |
| 396 | shm_destroy(ns, shp); |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | /* Remove the list head from any segments still attached. */ |
Jack Miller | ab602f7 | 2014-08-08 14:23:19 -0700 | [diff] [blame] | 401 | list_del(&task->sysvshm.shm_clist); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 402 | up_write(&shm_ids(ns).rwsem); |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 403 | } |
| 404 | |
Dave Jiang | 11bac80 | 2017-02-24 14:56:41 -0800 | [diff] [blame] | 405 | static int shm_fault(struct vm_fault *vmf) |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 406 | { |
Dave Jiang | 11bac80 | 2017-02-24 14:56:41 -0800 | [diff] [blame] | 407 | struct file *file = vmf->vma->vm_file; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 408 | struct shm_file_data *sfd = shm_file_data(file); |
| 409 | |
Dave Jiang | 11bac80 | 2017-02-24 14:56:41 -0800 | [diff] [blame] | 410 | return sfd->vm_ops->fault(vmf); |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 411 | } |
| 412 | |
| 413 | #ifdef CONFIG_NUMA |
Adrian Bunk | d823e3e | 2007-10-16 23:26:42 -0700 | [diff] [blame] | 414 | static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new) |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 415 | { |
| 416 | struct file *file = vma->vm_file; |
| 417 | struct shm_file_data *sfd = shm_file_data(file); |
| 418 | int err = 0; |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 419 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 420 | if (sfd->vm_ops->set_policy) |
| 421 | err = sfd->vm_ops->set_policy(vma, new); |
| 422 | return err; |
| 423 | } |
| 424 | |
Adrian Bunk | d823e3e | 2007-10-16 23:26:42 -0700 | [diff] [blame] | 425 | static struct mempolicy *shm_get_policy(struct vm_area_struct *vma, |
| 426 | unsigned long addr) |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 427 | { |
| 428 | struct file *file = vma->vm_file; |
| 429 | struct shm_file_data *sfd = shm_file_data(file); |
| 430 | struct mempolicy *pol = NULL; |
| 431 | |
| 432 | if (sfd->vm_ops->get_policy) |
| 433 | pol = sfd->vm_ops->get_policy(vma, addr); |
Lee Schermerhorn | 52cd3b0 | 2008-04-28 02:13:16 -0700 | [diff] [blame] | 434 | else if (vma->vm_policy) |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 435 | pol = vma->vm_policy; |
Lee Schermerhorn | 52cd3b0 | 2008-04-28 02:13:16 -0700 | [diff] [blame] | 436 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 437 | return pol; |
| 438 | } |
| 439 | #endif |
| 440 | |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 441 | static int shm_mmap(struct file *file, struct vm_area_struct *vma) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | { |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 443 | struct shm_file_data *sfd = shm_file_data(file); |
David Howells | b0e1519 | 2006-01-06 00:11:42 -0800 | [diff] [blame] | 444 | int ret; |
| 445 | |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 446 | /* |
| 447 | * In case of remap_file_pages() emulation, the file can represent |
| 448 | * removed IPC ID: propogate shm_lock() error to caller. |
| 449 | */ |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 450 | ret = __shm_open(vma); |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 451 | if (ret) |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 452 | return ret; |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 453 | |
Miklos Szeredi | f74ac01 | 2017-02-20 16:51:23 +0100 | [diff] [blame] | 454 | ret = call_mmap(sfd->file, vma); |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 455 | if (ret) { |
| 456 | shm_close(vma); |
| 457 | return ret; |
| 458 | } |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 459 | sfd->vm_ops = vma->vm_ops; |
David Howells | 2e92a3b | 2007-07-31 00:37:24 -0700 | [diff] [blame] | 460 | #ifdef CONFIG_MMU |
Davidlohr Bueso | d0edd85 | 2015-09-09 15:39:20 -0700 | [diff] [blame] | 461 | WARN_ON(!sfd->vm_ops->fault); |
David Howells | 2e92a3b | 2007-07-31 00:37:24 -0700 | [diff] [blame] | 462 | #endif |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 463 | vma->vm_ops = &shm_vm_ops; |
Kirill A. Shutemov | 1ac0b6d | 2016-02-17 13:11:35 -0800 | [diff] [blame] | 464 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | } |
| 466 | |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 467 | static int shm_release(struct inode *ino, struct file *file) |
| 468 | { |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 469 | struct shm_file_data *sfd = shm_file_data(file); |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 470 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 471 | put_ipc_ns(sfd->ns); |
| 472 | shm_file_data(file) = NULL; |
| 473 | kfree(sfd); |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 474 | return 0; |
| 475 | } |
| 476 | |
Josef Bacik | 02c24a8 | 2011-07-16 20:44:56 -0400 | [diff] [blame] | 477 | static int shm_fsync(struct file *file, loff_t start, loff_t end, int datasync) |
Adam Litke | 516dffd | 2007-03-01 15:46:08 -0800 | [diff] [blame] | 478 | { |
Adam Litke | 516dffd | 2007-03-01 15:46:08 -0800 | [diff] [blame] | 479 | struct shm_file_data *sfd = shm_file_data(file); |
Adam Litke | 516dffd | 2007-03-01 15:46:08 -0800 | [diff] [blame] | 480 | |
Christoph Hellwig | 7ea8085 | 2010-05-26 17:53:25 +0200 | [diff] [blame] | 481 | if (!sfd->file->f_op->fsync) |
| 482 | return -EINVAL; |
Jeff Layton | 0f41074 | 2017-07-05 15:26:50 -0400 | [diff] [blame] | 483 | return sfd->file->f_op->fsync(sfd->file, start, end, datasync); |
Adam Litke | 516dffd | 2007-03-01 15:46:08 -0800 | [diff] [blame] | 484 | } |
| 485 | |
Will Deacon | 7d8a456 | 2012-06-07 14:21:13 -0700 | [diff] [blame] | 486 | static long shm_fallocate(struct file *file, int mode, loff_t offset, |
| 487 | loff_t len) |
| 488 | { |
| 489 | struct shm_file_data *sfd = shm_file_data(file); |
| 490 | |
| 491 | if (!sfd->file->f_op->fallocate) |
| 492 | return -EOPNOTSUPP; |
| 493 | return sfd->file->f_op->fallocate(file, mode, offset, len); |
| 494 | } |
| 495 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 496 | static unsigned long shm_get_unmapped_area(struct file *file, |
| 497 | unsigned long addr, unsigned long len, unsigned long pgoff, |
| 498 | unsigned long flags) |
| 499 | { |
| 500 | struct shm_file_data *sfd = shm_file_data(file); |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 501 | |
Al Viro | c4caa77 | 2009-11-30 08:38:43 -0500 | [diff] [blame] | 502 | return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len, |
| 503 | pgoff, flags); |
Adam Litke | 516dffd | 2007-03-01 15:46:08 -0800 | [diff] [blame] | 504 | } |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 505 | |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 506 | static const struct file_operations shm_file_operations = { |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 507 | .mmap = shm_mmap, |
Adam Litke | 516dffd | 2007-03-01 15:46:08 -0800 | [diff] [blame] | 508 | .fsync = shm_fsync, |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 509 | .release = shm_release, |
David Howells | ed5e589 | 2010-01-15 17:01:32 -0800 | [diff] [blame] | 510 | .get_unmapped_area = shm_get_unmapped_area, |
Arnd Bergmann | 6038f37 | 2010-08-15 18:52:59 +0200 | [diff] [blame] | 511 | .llseek = noop_llseek, |
Will Deacon | 7d8a456 | 2012-06-07 14:21:13 -0700 | [diff] [blame] | 512 | .fallocate = shm_fallocate, |
Al Viro | c4caa77 | 2009-11-30 08:38:43 -0500 | [diff] [blame] | 513 | }; |
| 514 | |
Hugh Dickins | c01d5b3 | 2016-07-26 15:26:15 -0700 | [diff] [blame] | 515 | /* |
| 516 | * shm_file_operations_huge is now identical to shm_file_operations, |
| 517 | * but we keep it distinct for the sake of is_file_shm_hugepages(). |
| 518 | */ |
Al Viro | c4caa77 | 2009-11-30 08:38:43 -0500 | [diff] [blame] | 519 | static const struct file_operations shm_file_operations_huge = { |
| 520 | .mmap = shm_mmap, |
| 521 | .fsync = shm_fsync, |
| 522 | .release = shm_release, |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 523 | .get_unmapped_area = shm_get_unmapped_area, |
Arnd Bergmann | 6038f37 | 2010-08-15 18:52:59 +0200 | [diff] [blame] | 524 | .llseek = noop_llseek, |
Will Deacon | 7d8a456 | 2012-06-07 14:21:13 -0700 | [diff] [blame] | 525 | .fallocate = shm_fallocate, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | }; |
| 527 | |
Yaowei Bai | 2954e440 | 2016-01-20 15:01:11 -0800 | [diff] [blame] | 528 | bool is_file_shm_hugepages(struct file *file) |
Al Viro | c4caa77 | 2009-11-30 08:38:43 -0500 | [diff] [blame] | 529 | { |
| 530 | return file->f_op == &shm_file_operations_huge; |
| 531 | } |
| 532 | |
Alexey Dobriyan | f0f37e2f | 2009-09-27 22:29:37 +0400 | [diff] [blame] | 533 | static const struct vm_operations_struct shm_vm_ops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 534 | .open = shm_open, /* callback for a new vm-area open */ |
| 535 | .close = shm_close, /* callback for when the vm-area is released */ |
Nick Piggin | 54cb882 | 2007-07-19 01:46:59 -0700 | [diff] [blame] | 536 | .fault = shm_fault, |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 537 | #if defined(CONFIG_NUMA) |
| 538 | .set_policy = shm_set_policy, |
| 539 | .get_policy = shm_get_policy, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | #endif |
| 541 | }; |
| 542 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 543 | /** |
| 544 | * newseg - Create a new shared memory segment |
| 545 | * @ns: namespace |
| 546 | * @params: ptr to the structure that contains key, size and shmflg |
| 547 | * |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 548 | * Called with shm_ids.rwsem held as a writer. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 549 | */ |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 550 | static int newseg(struct ipc_namespace *ns, struct ipc_params *params) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | { |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 552 | key_t key = params->key; |
| 553 | int shmflg = params->flg; |
| 554 | size_t size = params->u.size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | int error; |
| 556 | struct shmid_kernel *shp; |
Robin Holt | d69f3ba | 2013-04-30 19:15:54 -0700 | [diff] [blame] | 557 | size_t numpages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 558 | struct file *file; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | char name[13]; |
KOSAKI Motohiro | ca16d14 | 2011-05-26 19:16:19 +0900 | [diff] [blame] | 560 | vm_flags_t acctflag = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 562 | if (size < SHMMIN || size > ns->shm_ctlmax) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | return -EINVAL; |
| 564 | |
Manfred Spraul | 1376327 | 2014-06-06 14:37:41 -0700 | [diff] [blame] | 565 | if (numpages << PAGE_SHIFT < size) |
| 566 | return -ENOSPC; |
| 567 | |
Manfred Spraul | 09c6eb1 | 2014-06-06 14:37:40 -0700 | [diff] [blame] | 568 | if (ns->shm_tot + numpages < ns->shm_tot || |
| 569 | ns->shm_tot + numpages > ns->shm_ctlall) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | return -ENOSPC; |
| 571 | |
Kees Cook | 42e618f | 2017-07-12 14:35:25 -0700 | [diff] [blame] | 572 | shp = kvmalloc(sizeof(*shp), GFP_KERNEL); |
| 573 | if (unlikely(!shp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | return -ENOMEM; |
| 575 | |
| 576 | shp->shm_perm.key = key; |
Andrew Morton | b33291c | 2006-01-08 01:02:21 -0800 | [diff] [blame] | 577 | shp->shm_perm.mode = (shmflg & S_IRWXUGO); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | shp->mlock_user = NULL; |
| 579 | |
| 580 | shp->shm_perm.security = NULL; |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 581 | error = security_shm_alloc(&shp->shm_perm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 582 | if (error) { |
Kees Cook | 42e618f | 2017-07-12 14:35:25 -0700 | [diff] [blame] | 583 | kvfree(shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | return error; |
| 585 | } |
| 586 | |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 587 | sprintf(name, "SYSV%08x", key); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | if (shmflg & SHM_HUGETLB) { |
Andrew Morton | c103a4d | 2013-07-08 16:01:08 -0700 | [diff] [blame] | 589 | struct hstate *hs; |
Li Zefan | 091d0d5 | 2013-05-09 15:08:15 +0800 | [diff] [blame] | 590 | size_t hugesize; |
| 591 | |
Andrew Morton | c103a4d | 2013-07-08 16:01:08 -0700 | [diff] [blame] | 592 | hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK); |
Li Zefan | 091d0d5 | 2013-05-09 15:08:15 +0800 | [diff] [blame] | 593 | if (!hs) { |
| 594 | error = -EINVAL; |
| 595 | goto no_file; |
| 596 | } |
| 597 | hugesize = ALIGN(size, huge_page_size(hs)); |
Naoya Horiguchi | af73e4d | 2013-05-07 16:18:13 -0700 | [diff] [blame] | 598 | |
Mel Gorman | 5a6fe12 | 2009-02-10 14:02:27 +0000 | [diff] [blame] | 599 | /* hugetlb_file_setup applies strict accounting */ |
| 600 | if (shmflg & SHM_NORESERVE) |
| 601 | acctflag = VM_NORESERVE; |
Naoya Horiguchi | af73e4d | 2013-05-07 16:18:13 -0700 | [diff] [blame] | 602 | file = hugetlb_file_setup(name, hugesize, acctflag, |
Andi Kleen | 42d7395 | 2012-12-11 16:01:34 -0800 | [diff] [blame] | 603 | &shp->mlock_user, HUGETLB_SHMFS_INODE, |
| 604 | (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | } else { |
Badari Pulavarty | bf8f972 | 2005-11-07 00:59:27 -0800 | [diff] [blame] | 606 | /* |
| 607 | * Do not allow no accounting for OVERCOMMIT_NEVER, even |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 608 | * if it's asked for. |
Badari Pulavarty | bf8f972 | 2005-11-07 00:59:27 -0800 | [diff] [blame] | 609 | */ |
| 610 | if ((shmflg & SHM_NORESERVE) && |
| 611 | sysctl_overcommit_memory != OVERCOMMIT_NEVER) |
Linus Torvalds | fc8744a | 2009-01-31 15:08:56 -0800 | [diff] [blame] | 612 | acctflag = VM_NORESERVE; |
Stephen Smalley | e1832f2 | 2015-08-06 15:46:55 -0700 | [diff] [blame] | 613 | file = shmem_kernel_file_setup(name, size, acctflag); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | } |
| 615 | error = PTR_ERR(file); |
| 616 | if (IS_ERR(file)) |
| 617 | goto no_file; |
| 618 | |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 619 | shp->shm_cprid = get_pid(task_tgid(current)); |
| 620 | shp->shm_lprid = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | shp->shm_atim = shp->shm_dtim = 0; |
Deepa Dinamani | 7ff2819 | 2017-08-02 19:51:14 -0700 | [diff] [blame] | 622 | shp->shm_ctim = ktime_get_real_seconds(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | shp->shm_segsz = size; |
| 624 | shp->shm_nattch = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | shp->shm_file = file; |
Vasiliy Kulikov | 5774ed0 | 2011-07-29 03:55:31 +0400 | [diff] [blame] | 626 | shp->shm_creator = current; |
Linus Torvalds | b9a5322 | 2015-09-30 12:48:40 -0400 | [diff] [blame] | 627 | |
Davidlohr Bueso | 39c96a1 | 2017-11-17 15:31:11 -0800 | [diff] [blame] | 628 | /* ipc_addid() locks shp upon success. */ |
Manfred Spraul | a2642f8 | 2017-07-12 14:35:16 -0700 | [diff] [blame] | 629 | error = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni); |
| 630 | if (error < 0) |
Linus Torvalds | b9a5322 | 2015-09-30 12:48:40 -0400 | [diff] [blame] | 631 | goto no_id; |
Linus Torvalds | b9a5322 | 2015-09-30 12:48:40 -0400 | [diff] [blame] | 632 | |
Jack Miller | ab602f7 | 2014-08-08 14:23:19 -0700 | [diff] [blame] | 633 | list_add(&shp->shm_clist, ¤t->sysvshm.shm_clist); |
Davidlohr Bueso | dbfcd91 | 2013-07-08 16:01:09 -0700 | [diff] [blame] | 634 | |
Badari Pulavarty | 30475cc | 2007-06-16 10:15:59 -0700 | [diff] [blame] | 635 | /* |
| 636 | * shmid gets reported as "inode#" in /proc/pid/maps. |
| 637 | * proc-ps tools use this. Changing this will break them. |
| 638 | */ |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 639 | file_inode(file)->i_ino = shp->shm_perm.id; |
Krishnakumar R | 551110a | 2005-10-29 18:16:45 -0700 | [diff] [blame] | 640 | |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 641 | ns->shm_tot += numpages; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 642 | error = shp->shm_perm.id; |
Davidlohr Bueso | dbfcd91 | 2013-07-08 16:01:09 -0700 | [diff] [blame] | 643 | |
Davidlohr Bueso | cf9d5d7 | 2013-07-08 16:01:11 -0700 | [diff] [blame] | 644 | ipc_unlock_object(&shp->shm_perm); |
Davidlohr Bueso | dbfcd91 | 2013-07-08 16:01:09 -0700 | [diff] [blame] | 645 | rcu_read_unlock(); |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 646 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | |
| 648 | no_id: |
Hugh Dickins | 2195d281 | 2009-09-12 12:21:27 +0100 | [diff] [blame] | 649 | if (is_file_hugepages(file) && shp->mlock_user) |
Hugh Dickins | 353d5c3 | 2009-08-24 16:30:28 +0100 | [diff] [blame] | 650 | user_shm_unlock(size, shp->mlock_user); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 651 | fput(file); |
| 652 | no_file: |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 653 | ipc_update_pid(&shp->shm_cprid, NULL); |
| 654 | ipc_update_pid(&shp->shm_lprid, NULL); |
Manfred Spraul | a2642f8 | 2017-07-12 14:35:16 -0700 | [diff] [blame] | 655 | call_rcu(&shp->shm_perm.rcu, shm_rcu_free); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 656 | return error; |
| 657 | } |
| 658 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 659 | /* |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 660 | * Called with shm_ids.rwsem and ipcp locked. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 661 | */ |
Nadia Derbey | 03f02c7 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 662 | static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 663 | { |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 664 | return security_shm_associate(ipcp, shmflg); |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 665 | } |
| 666 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 667 | /* |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 668 | * Called with shm_ids.rwsem and ipcp locked. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 669 | */ |
Nadia Derbey | 03f02c7 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 670 | static inline int shm_more_checks(struct kern_ipc_perm *ipcp, |
| 671 | struct ipc_params *params) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 672 | { |
Nadia Derbey | 03f02c7 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 673 | struct shmid_kernel *shp; |
| 674 | |
| 675 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); |
| 676 | if (shp->shm_segsz < params->u.size) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 677 | return -EINVAL; |
| 678 | |
| 679 | return 0; |
| 680 | } |
| 681 | |
Heiko Carstens | d5460c9 | 2009-01-14 14:14:27 +0100 | [diff] [blame] | 682 | SYSCALL_DEFINE3(shmget, key_t, key, size_t, size, int, shmflg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | { |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 684 | struct ipc_namespace *ns; |
Mathias Krause | eb66ec4 | 2014-06-06 14:37:36 -0700 | [diff] [blame] | 685 | static const struct ipc_ops shm_ops = { |
| 686 | .getnew = newseg, |
| 687 | .associate = shm_security, |
| 688 | .more_checks = shm_more_checks, |
| 689 | }; |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 690 | struct ipc_params shm_params; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 692 | ns = current->nsproxy->ipc_ns; |
| 693 | |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 694 | shm_params.key = key; |
| 695 | shm_params.flg = shmflg; |
| 696 | shm_params.u.size = size; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 697 | |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 698 | return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | } |
| 700 | |
| 701 | static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version) |
| 702 | { |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 703 | switch (version) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | case IPC_64: |
| 705 | return copy_to_user(buf, in, sizeof(*in)); |
| 706 | case IPC_OLD: |
| 707 | { |
| 708 | struct shmid_ds out; |
| 709 | |
Vasiliy Kulikov | 3af54c9 | 2010-10-30 18:22:49 +0400 | [diff] [blame] | 710 | memset(&out, 0, sizeof(out)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm); |
| 712 | out.shm_segsz = in->shm_segsz; |
| 713 | out.shm_atime = in->shm_atime; |
| 714 | out.shm_dtime = in->shm_dtime; |
| 715 | out.shm_ctime = in->shm_ctime; |
| 716 | out.shm_cpid = in->shm_cpid; |
| 717 | out.shm_lpid = in->shm_lpid; |
| 718 | out.shm_nattch = in->shm_nattch; |
| 719 | |
| 720 | return copy_to_user(buf, &out, sizeof(out)); |
| 721 | } |
| 722 | default: |
| 723 | return -EINVAL; |
| 724 | } |
| 725 | } |
| 726 | |
Pierre Peiffer | 016d713 | 2008-04-29 01:00:50 -0700 | [diff] [blame] | 727 | static inline unsigned long |
| 728 | copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | { |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 730 | switch (version) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | case IPC_64: |
Pierre Peiffer | 016d713 | 2008-04-29 01:00:50 -0700 | [diff] [blame] | 732 | if (copy_from_user(out, buf, sizeof(*out))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | case IPC_OLD: |
| 736 | { |
| 737 | struct shmid_ds tbuf_old; |
| 738 | |
| 739 | if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) |
| 740 | return -EFAULT; |
| 741 | |
Pierre Peiffer | 016d713 | 2008-04-29 01:00:50 -0700 | [diff] [blame] | 742 | out->shm_perm.uid = tbuf_old.shm_perm.uid; |
| 743 | out->shm_perm.gid = tbuf_old.shm_perm.gid; |
| 744 | out->shm_perm.mode = tbuf_old.shm_perm.mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 745 | |
| 746 | return 0; |
| 747 | } |
| 748 | default: |
| 749 | return -EINVAL; |
| 750 | } |
| 751 | } |
| 752 | |
| 753 | static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version) |
| 754 | { |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 755 | switch (version) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | case IPC_64: |
| 757 | return copy_to_user(buf, in, sizeof(*in)); |
| 758 | case IPC_OLD: |
| 759 | { |
| 760 | struct shminfo out; |
| 761 | |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 762 | if (in->shmmax > INT_MAX) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | out.shmmax = INT_MAX; |
| 764 | else |
| 765 | out.shmmax = (int)in->shmmax; |
| 766 | |
| 767 | out.shmmin = in->shmmin; |
| 768 | out.shmmni = in->shmmni; |
| 769 | out.shmseg = in->shmseg; |
Paul McQuade | 46c0a8c | 2014-06-06 14:37:37 -0700 | [diff] [blame] | 770 | out.shmall = in->shmall; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 771 | |
| 772 | return copy_to_user(buf, &out, sizeof(out)); |
| 773 | } |
| 774 | default: |
| 775 | return -EINVAL; |
| 776 | } |
| 777 | } |
| 778 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 779 | /* |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 780 | * Calculate and add used RSS and swap pages of a shm. |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 781 | * Called with shm_ids.rwsem held as a reader |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 782 | */ |
| 783 | static void shm_add_rss_swap(struct shmid_kernel *shp, |
| 784 | unsigned long *rss_add, unsigned long *swp_add) |
| 785 | { |
| 786 | struct inode *inode; |
| 787 | |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 788 | inode = file_inode(shp->shm_file); |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 789 | |
| 790 | if (is_file_hugepages(shp->shm_file)) { |
| 791 | struct address_space *mapping = inode->i_mapping; |
| 792 | struct hstate *h = hstate_file(shp->shm_file); |
| 793 | *rss_add += pages_per_huge_page(h) * mapping->nrpages; |
| 794 | } else { |
| 795 | #ifdef CONFIG_SHMEM |
| 796 | struct shmem_inode_info *info = SHMEM_I(inode); |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 797 | |
Kirill A. Shutemov | 4595ef8 | 2016-07-26 15:26:29 -0700 | [diff] [blame] | 798 | spin_lock_irq(&info->lock); |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 799 | *rss_add += inode->i_mapping->nrpages; |
| 800 | *swp_add += info->swapped; |
Kirill A. Shutemov | 4595ef8 | 2016-07-26 15:26:29 -0700 | [diff] [blame] | 801 | spin_unlock_irq(&info->lock); |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 802 | #else |
| 803 | *rss_add += inode->i_mapping->nrpages; |
| 804 | #endif |
| 805 | } |
| 806 | } |
| 807 | |
| 808 | /* |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 809 | * Called with shm_ids.rwsem held as a reader |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 810 | */ |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 811 | static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss, |
| 812 | unsigned long *swp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 813 | { |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 814 | int next_id; |
| 815 | int total, in_use; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | |
| 817 | *rss = 0; |
| 818 | *swp = 0; |
| 819 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 820 | in_use = shm_ids(ns).in_use; |
| 821 | |
| 822 | for (total = 0, next_id = 0; total < in_use; next_id++) { |
Tony Battersby | e562aeb | 2009-04-02 16:58:26 -0700 | [diff] [blame] | 823 | struct kern_ipc_perm *ipc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 824 | struct shmid_kernel *shp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | |
Tony Battersby | e562aeb | 2009-04-02 16:58:26 -0700 | [diff] [blame] | 826 | ipc = idr_find(&shm_ids(ns).ipcs_idr, next_id); |
| 827 | if (ipc == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 828 | continue; |
Tony Battersby | e562aeb | 2009-04-02 16:58:26 -0700 | [diff] [blame] | 829 | shp = container_of(ipc, struct shmid_kernel, shm_perm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 830 | |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 831 | shm_add_rss_swap(shp, rss, swp); |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 832 | |
| 833 | total++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 834 | } |
| 835 | } |
| 836 | |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 837 | /* |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 838 | * This function handles some shmctl commands which require the rwsem |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 839 | * to be held in write mode. |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 840 | * NOTE: no locks must be held, the rwsem is taken inside this function. |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 841 | */ |
| 842 | static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd, |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 843 | struct shmid64_ds *shmid64) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 844 | { |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 845 | struct kern_ipc_perm *ipcp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | struct shmid_kernel *shp; |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 847 | int err; |
| 848 | |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 849 | down_write(&shm_ids(ns).rwsem); |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 850 | rcu_read_lock(); |
| 851 | |
Davidlohr Bueso | 79ccf0f | 2013-09-11 14:26:16 -0700 | [diff] [blame] | 852 | ipcp = ipcctl_pre_down_nolock(ns, &shm_ids(ns), shmid, cmd, |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 853 | &shmid64->shm_perm, 0); |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 854 | if (IS_ERR(ipcp)) { |
| 855 | err = PTR_ERR(ipcp); |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 856 | goto out_unlock1; |
| 857 | } |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 858 | |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 859 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 860 | |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 861 | err = security_shm_shmctl(&shp->shm_perm, cmd); |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 862 | if (err) |
Davidlohr Bueso | 79ccf0f | 2013-09-11 14:26:16 -0700 | [diff] [blame] | 863 | goto out_unlock1; |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 864 | |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 865 | switch (cmd) { |
| 866 | case IPC_RMID: |
Davidlohr Bueso | 79ccf0f | 2013-09-11 14:26:16 -0700 | [diff] [blame] | 867 | ipc_lock_object(&shp->shm_perm); |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 868 | /* do_shm_rmid unlocks the ipc object and rcu */ |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 869 | do_shm_rmid(ns, ipcp); |
| 870 | goto out_up; |
| 871 | case IPC_SET: |
Davidlohr Bueso | 79ccf0f | 2013-09-11 14:26:16 -0700 | [diff] [blame] | 872 | ipc_lock_object(&shp->shm_perm); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 873 | err = ipc_update_perm(&shmid64->shm_perm, ipcp); |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 874 | if (err) |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 875 | goto out_unlock0; |
Deepa Dinamani | 7ff2819 | 2017-08-02 19:51:14 -0700 | [diff] [blame] | 876 | shp->shm_ctim = ktime_get_real_seconds(); |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 877 | break; |
| 878 | default: |
| 879 | err = -EINVAL; |
Davidlohr Bueso | 79ccf0f | 2013-09-11 14:26:16 -0700 | [diff] [blame] | 880 | goto out_unlock1; |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 881 | } |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 882 | |
| 883 | out_unlock0: |
| 884 | ipc_unlock_object(&shp->shm_perm); |
| 885 | out_unlock1: |
| 886 | rcu_read_unlock(); |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 887 | out_up: |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 888 | up_write(&shm_ids(ns).rwsem); |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 889 | return err; |
| 890 | } |
| 891 | |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 892 | static int shmctl_ipc_info(struct ipc_namespace *ns, |
| 893 | struct shminfo64 *shminfo) |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 894 | { |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 895 | int err = security_shm_shmctl(NULL, IPC_INFO); |
| 896 | if (!err) { |
| 897 | memset(shminfo, 0, sizeof(*shminfo)); |
| 898 | shminfo->shmmni = shminfo->shmseg = ns->shm_ctlmni; |
| 899 | shminfo->shmmax = ns->shm_ctlmax; |
| 900 | shminfo->shmall = ns->shm_ctlall; |
| 901 | shminfo->shmmin = SHMMIN; |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 902 | down_read(&shm_ids(ns).rwsem); |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 903 | err = ipc_get_maxid(&shm_ids(ns)); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 904 | up_read(&shm_ids(ns).rwsem); |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 905 | if (err < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | err = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 907 | } |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 908 | return err; |
| 909 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 910 | |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 911 | static int shmctl_shm_info(struct ipc_namespace *ns, |
| 912 | struct shm_info *shm_info) |
| 913 | { |
| 914 | int err = security_shm_shmctl(NULL, SHM_INFO); |
| 915 | if (!err) { |
| 916 | memset(shm_info, 0, sizeof(*shm_info)); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 917 | down_read(&shm_ids(ns).rwsem); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 918 | shm_info->used_ids = shm_ids(ns).in_use; |
| 919 | shm_get_stat(ns, &shm_info->shm_rss, &shm_info->shm_swp); |
| 920 | shm_info->shm_tot = ns->shm_tot; |
| 921 | shm_info->swap_attempts = 0; |
| 922 | shm_info->swap_successes = 0; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 923 | err = ipc_get_maxid(&shm_ids(ns)); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 924 | up_read(&shm_ids(ns).rwsem); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 925 | if (err < 0) |
| 926 | err = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 927 | } |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 928 | return err; |
| 929 | } |
Nadia Derbey | 023a535 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 930 | |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 931 | static int shmctl_stat(struct ipc_namespace *ns, int shmid, |
| 932 | int cmd, struct shmid64_ds *tbuf) |
| 933 | { |
| 934 | struct shmid_kernel *shp; |
Philippe Mikoyan | 87ad4b0 | 2018-02-06 15:40:49 -0800 | [diff] [blame] | 935 | int id = 0; |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 936 | int err; |
Davidlohr Bueso | c97cb9c | 2013-09-11 14:26:20 -0700 | [diff] [blame] | 937 | |
Philippe Mikoyan | 87ad4b0 | 2018-02-06 15:40:49 -0800 | [diff] [blame] | 938 | memset(tbuf, 0, sizeof(*tbuf)); |
| 939 | |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 940 | rcu_read_lock(); |
| 941 | if (cmd == SHM_STAT) { |
| 942 | shp = shm_obtain_object(ns, shmid); |
| 943 | if (IS_ERR(shp)) { |
| 944 | err = PTR_ERR(shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 945 | goto out_unlock; |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 946 | } |
Philippe Mikoyan | 87ad4b0 | 2018-02-06 15:40:49 -0800 | [diff] [blame] | 947 | id = shp->shm_perm.id; |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 948 | } else { |
| 949 | shp = shm_obtain_object_check(ns, shmid); |
| 950 | if (IS_ERR(shp)) { |
| 951 | err = PTR_ERR(shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 952 | goto out_unlock; |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 953 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | } |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 955 | |
| 956 | err = -EACCES; |
| 957 | if (ipcperms(ns, &shp->shm_perm, S_IRUGO)) |
| 958 | goto out_unlock; |
| 959 | |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 960 | err = security_shm_shmctl(&shp->shm_perm, cmd); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 961 | if (err) |
| 962 | goto out_unlock; |
| 963 | |
Philippe Mikoyan | 87ad4b0 | 2018-02-06 15:40:49 -0800 | [diff] [blame] | 964 | ipc_lock_object(&shp->shm_perm); |
| 965 | |
| 966 | if (!ipc_valid_object(&shp->shm_perm)) { |
| 967 | ipc_unlock_object(&shp->shm_perm); |
| 968 | err = -EIDRM; |
| 969 | goto out_unlock; |
| 970 | } |
| 971 | |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 972 | kernel_to_ipc64_perm(&shp->shm_perm, &tbuf->shm_perm); |
| 973 | tbuf->shm_segsz = shp->shm_segsz; |
| 974 | tbuf->shm_atime = shp->shm_atim; |
| 975 | tbuf->shm_dtime = shp->shm_dtim; |
| 976 | tbuf->shm_ctime = shp->shm_ctim; |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 977 | tbuf->shm_cpid = pid_vnr(shp->shm_cprid); |
| 978 | tbuf->shm_lpid = pid_vnr(shp->shm_lprid); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 979 | tbuf->shm_nattch = shp->shm_nattch; |
Philippe Mikoyan | 87ad4b0 | 2018-02-06 15:40:49 -0800 | [diff] [blame] | 980 | |
| 981 | ipc_unlock_object(&shp->shm_perm); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 982 | rcu_read_unlock(); |
Philippe Mikoyan | 87ad4b0 | 2018-02-06 15:40:49 -0800 | [diff] [blame] | 983 | return id; |
Davidlohr Bueso | 68eccc1 | 2013-09-11 14:26:18 -0700 | [diff] [blame] | 984 | |
| 985 | out_unlock: |
Davidlohr Bueso | c97cb9c | 2013-09-11 14:26:20 -0700 | [diff] [blame] | 986 | rcu_read_unlock(); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 987 | return err; |
| 988 | } |
| 989 | |
| 990 | static int shmctl_do_lock(struct ipc_namespace *ns, int shmid, int cmd) |
| 991 | { |
| 992 | struct shmid_kernel *shp; |
| 993 | struct file *shm_file; |
| 994 | int err; |
| 995 | |
| 996 | rcu_read_lock(); |
| 997 | shp = shm_obtain_object_check(ns, shmid); |
| 998 | if (IS_ERR(shp)) { |
| 999 | err = PTR_ERR(shp); |
| 1000 | goto out_unlock1; |
| 1001 | } |
| 1002 | |
| 1003 | audit_ipc_obj(&(shp->shm_perm)); |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 1004 | err = security_shm_shmctl(&shp->shm_perm, cmd); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1005 | if (err) |
| 1006 | goto out_unlock1; |
| 1007 | |
| 1008 | ipc_lock_object(&shp->shm_perm); |
| 1009 | |
| 1010 | /* check if shm_destroy() is tearing down shp */ |
| 1011 | if (!ipc_valid_object(&shp->shm_perm)) { |
| 1012 | err = -EIDRM; |
| 1013 | goto out_unlock0; |
| 1014 | } |
| 1015 | |
| 1016 | if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) { |
| 1017 | kuid_t euid = current_euid(); |
| 1018 | |
| 1019 | if (!uid_eq(euid, shp->shm_perm.uid) && |
| 1020 | !uid_eq(euid, shp->shm_perm.cuid)) { |
| 1021 | err = -EPERM; |
| 1022 | goto out_unlock0; |
| 1023 | } |
| 1024 | if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK)) { |
| 1025 | err = -EPERM; |
| 1026 | goto out_unlock0; |
| 1027 | } |
| 1028 | } |
| 1029 | |
| 1030 | shm_file = shp->shm_file; |
| 1031 | if (is_file_hugepages(shm_file)) |
| 1032 | goto out_unlock0; |
| 1033 | |
| 1034 | if (cmd == SHM_LOCK) { |
| 1035 | struct user_struct *user = current_user(); |
| 1036 | |
| 1037 | err = shmem_lock(shm_file, 1, user); |
| 1038 | if (!err && !(shp->shm_perm.mode & SHM_LOCKED)) { |
| 1039 | shp->shm_perm.mode |= SHM_LOCKED; |
| 1040 | shp->mlock_user = user; |
| 1041 | } |
| 1042 | goto out_unlock0; |
| 1043 | } |
| 1044 | |
| 1045 | /* SHM_UNLOCK */ |
| 1046 | if (!(shp->shm_perm.mode & SHM_LOCKED)) |
| 1047 | goto out_unlock0; |
| 1048 | shmem_lock(shm_file, 0, shp->mlock_user); |
| 1049 | shp->shm_perm.mode &= ~SHM_LOCKED; |
| 1050 | shp->mlock_user = NULL; |
| 1051 | get_file(shm_file); |
| 1052 | ipc_unlock_object(&shp->shm_perm); |
| 1053 | rcu_read_unlock(); |
| 1054 | shmem_unlock_mapping(shm_file->f_mapping); |
| 1055 | |
| 1056 | fput(shm_file); |
| 1057 | return err; |
| 1058 | |
| 1059 | out_unlock0: |
| 1060 | ipc_unlock_object(&shp->shm_perm); |
| 1061 | out_unlock1: |
| 1062 | rcu_read_unlock(); |
Davidlohr Bueso | 68eccc1 | 2013-09-11 14:26:18 -0700 | [diff] [blame] | 1063 | return err; |
| 1064 | } |
| 1065 | |
| 1066 | SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) |
| 1067 | { |
Davidlohr Bueso | 68eccc1 | 2013-09-11 14:26:18 -0700 | [diff] [blame] | 1068 | int err, version; |
| 1069 | struct ipc_namespace *ns; |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1070 | struct shmid64_ds sem64; |
Davidlohr Bueso | 68eccc1 | 2013-09-11 14:26:18 -0700 | [diff] [blame] | 1071 | |
Davidlohr Bueso | 2caacaa | 2013-09-11 14:26:21 -0700 | [diff] [blame] | 1072 | if (cmd < 0 || shmid < 0) |
| 1073 | return -EINVAL; |
Davidlohr Bueso | 68eccc1 | 2013-09-11 14:26:18 -0700 | [diff] [blame] | 1074 | |
| 1075 | version = ipc_parse_version(&cmd); |
| 1076 | ns = current->nsproxy->ipc_ns; |
| 1077 | |
| 1078 | switch (cmd) { |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1079 | case IPC_INFO: { |
| 1080 | struct shminfo64 shminfo; |
| 1081 | err = shmctl_ipc_info(ns, &shminfo); |
| 1082 | if (err < 0) |
| 1083 | return err; |
| 1084 | if (copy_shminfo_to_user(buf, &shminfo, version)) |
| 1085 | err = -EFAULT; |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 1086 | return err; |
Davidlohr Bueso | 2caacaa | 2013-09-11 14:26:21 -0700 | [diff] [blame] | 1087 | } |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1088 | case SHM_INFO: { |
| 1089 | struct shm_info shm_info; |
| 1090 | err = shmctl_shm_info(ns, &shm_info); |
| 1091 | if (err < 0) |
| 1092 | return err; |
| 1093 | if (copy_to_user(buf, &shm_info, sizeof(shm_info))) |
| 1094 | err = -EFAULT; |
| 1095 | return err; |
| 1096 | } |
| 1097 | case SHM_STAT: |
| 1098 | case IPC_STAT: { |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1099 | err = shmctl_stat(ns, shmid, cmd, &sem64); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1100 | if (err < 0) |
| 1101 | return err; |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1102 | if (copy_shmid_to_user(buf, &sem64, version)) |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1103 | err = -EFAULT; |
| 1104 | return err; |
| 1105 | } |
| 1106 | case IPC_SET: |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1107 | if (copy_shmid_from_user(&sem64, buf, version)) |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1108 | return -EFAULT; |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1109 | /* fallthru */ |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1110 | case IPC_RMID: |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1111 | return shmctl_down(ns, shmid, cmd, &sem64); |
Al Viro | 9ba720c | 2017-07-08 20:58:06 -0400 | [diff] [blame] | 1112 | case SHM_LOCK: |
| 1113 | case SHM_UNLOCK: |
| 1114 | return shmctl_do_lock(ns, shmid, cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1115 | default: |
Pierre Peiffer | 8d4cc8b | 2008-04-29 01:00:47 -0700 | [diff] [blame] | 1116 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1117 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1118 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1120 | #ifdef CONFIG_COMPAT |
| 1121 | |
| 1122 | struct compat_shmid_ds { |
| 1123 | struct compat_ipc_perm shm_perm; |
| 1124 | int shm_segsz; |
| 1125 | compat_time_t shm_atime; |
| 1126 | compat_time_t shm_dtime; |
| 1127 | compat_time_t shm_ctime; |
| 1128 | compat_ipc_pid_t shm_cpid; |
| 1129 | compat_ipc_pid_t shm_lpid; |
| 1130 | unsigned short shm_nattch; |
| 1131 | unsigned short shm_unused; |
| 1132 | compat_uptr_t shm_unused2; |
| 1133 | compat_uptr_t shm_unused3; |
| 1134 | }; |
| 1135 | |
| 1136 | struct compat_shminfo64 { |
| 1137 | compat_ulong_t shmmax; |
| 1138 | compat_ulong_t shmmin; |
| 1139 | compat_ulong_t shmmni; |
| 1140 | compat_ulong_t shmseg; |
| 1141 | compat_ulong_t shmall; |
| 1142 | compat_ulong_t __unused1; |
| 1143 | compat_ulong_t __unused2; |
| 1144 | compat_ulong_t __unused3; |
| 1145 | compat_ulong_t __unused4; |
| 1146 | }; |
| 1147 | |
| 1148 | struct compat_shm_info { |
| 1149 | compat_int_t used_ids; |
| 1150 | compat_ulong_t shm_tot, shm_rss, shm_swp; |
| 1151 | compat_ulong_t swap_attempts, swap_successes; |
| 1152 | }; |
| 1153 | |
| 1154 | static int copy_compat_shminfo_to_user(void __user *buf, struct shminfo64 *in, |
| 1155 | int version) |
| 1156 | { |
| 1157 | if (in->shmmax > INT_MAX) |
| 1158 | in->shmmax = INT_MAX; |
| 1159 | if (version == IPC_64) { |
| 1160 | struct compat_shminfo64 info; |
| 1161 | memset(&info, 0, sizeof(info)); |
| 1162 | info.shmmax = in->shmmax; |
| 1163 | info.shmmin = in->shmmin; |
| 1164 | info.shmmni = in->shmmni; |
| 1165 | info.shmseg = in->shmseg; |
| 1166 | info.shmall = in->shmall; |
| 1167 | return copy_to_user(buf, &info, sizeof(info)); |
| 1168 | } else { |
| 1169 | struct shminfo info; |
| 1170 | memset(&info, 0, sizeof(info)); |
| 1171 | info.shmmax = in->shmmax; |
| 1172 | info.shmmin = in->shmmin; |
| 1173 | info.shmmni = in->shmmni; |
| 1174 | info.shmseg = in->shmseg; |
| 1175 | info.shmall = in->shmall; |
| 1176 | return copy_to_user(buf, &info, sizeof(info)); |
| 1177 | } |
| 1178 | } |
| 1179 | |
| 1180 | static int put_compat_shm_info(struct shm_info *ip, |
| 1181 | struct compat_shm_info __user *uip) |
| 1182 | { |
| 1183 | struct compat_shm_info info; |
| 1184 | |
| 1185 | memset(&info, 0, sizeof(info)); |
| 1186 | info.used_ids = ip->used_ids; |
| 1187 | info.shm_tot = ip->shm_tot; |
| 1188 | info.shm_rss = ip->shm_rss; |
| 1189 | info.shm_swp = ip->shm_swp; |
| 1190 | info.swap_attempts = ip->swap_attempts; |
| 1191 | info.swap_successes = ip->swap_successes; |
Al Viro | b776e4b | 2017-09-25 20:38:45 -0400 | [diff] [blame] | 1192 | return copy_to_user(uip, &info, sizeof(info)); |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1193 | } |
| 1194 | |
| 1195 | static int copy_compat_shmid_to_user(void __user *buf, struct shmid64_ds *in, |
| 1196 | int version) |
| 1197 | { |
| 1198 | if (version == IPC_64) { |
| 1199 | struct compat_shmid64_ds v; |
| 1200 | memset(&v, 0, sizeof(v)); |
Al Viro | 28327fa | 2017-07-09 10:10:32 -0400 | [diff] [blame] | 1201 | to_compat_ipc64_perm(&v.shm_perm, &in->shm_perm); |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1202 | v.shm_atime = in->shm_atime; |
| 1203 | v.shm_dtime = in->shm_dtime; |
| 1204 | v.shm_ctime = in->shm_ctime; |
| 1205 | v.shm_segsz = in->shm_segsz; |
| 1206 | v.shm_nattch = in->shm_nattch; |
| 1207 | v.shm_cpid = in->shm_cpid; |
| 1208 | v.shm_lpid = in->shm_lpid; |
| 1209 | return copy_to_user(buf, &v, sizeof(v)); |
| 1210 | } else { |
| 1211 | struct compat_shmid_ds v; |
| 1212 | memset(&v, 0, sizeof(v)); |
Al Viro | 28327fa | 2017-07-09 10:10:32 -0400 | [diff] [blame] | 1213 | to_compat_ipc_perm(&v.shm_perm, &in->shm_perm); |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1214 | v.shm_perm.key = in->shm_perm.key; |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1215 | v.shm_atime = in->shm_atime; |
| 1216 | v.shm_dtime = in->shm_dtime; |
| 1217 | v.shm_ctime = in->shm_ctime; |
| 1218 | v.shm_segsz = in->shm_segsz; |
| 1219 | v.shm_nattch = in->shm_nattch; |
| 1220 | v.shm_cpid = in->shm_cpid; |
| 1221 | v.shm_lpid = in->shm_lpid; |
| 1222 | return copy_to_user(buf, &v, sizeof(v)); |
| 1223 | } |
| 1224 | } |
| 1225 | |
| 1226 | static int copy_compat_shmid_from_user(struct shmid64_ds *out, void __user *buf, |
| 1227 | int version) |
| 1228 | { |
| 1229 | memset(out, 0, sizeof(*out)); |
| 1230 | if (version == IPC_64) { |
Linus Torvalds | 6aa211e | 2017-09-25 18:37:28 -0700 | [diff] [blame] | 1231 | struct compat_shmid64_ds __user *p = buf; |
Al Viro | 28327fa | 2017-07-09 10:10:32 -0400 | [diff] [blame] | 1232 | return get_compat_ipc64_perm(&out->shm_perm, &p->shm_perm); |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1233 | } else { |
Linus Torvalds | 6aa211e | 2017-09-25 18:37:28 -0700 | [diff] [blame] | 1234 | struct compat_shmid_ds __user *p = buf; |
Al Viro | 28327fa | 2017-07-09 10:10:32 -0400 | [diff] [blame] | 1235 | return get_compat_ipc_perm(&out->shm_perm, &p->shm_perm); |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1236 | } |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1237 | } |
| 1238 | |
| 1239 | COMPAT_SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, void __user *, uptr) |
| 1240 | { |
| 1241 | struct ipc_namespace *ns; |
| 1242 | struct shmid64_ds sem64; |
| 1243 | int version = compat_ipc_parse_version(&cmd); |
| 1244 | int err; |
| 1245 | |
| 1246 | ns = current->nsproxy->ipc_ns; |
| 1247 | |
| 1248 | if (cmd < 0 || shmid < 0) |
| 1249 | return -EINVAL; |
| 1250 | |
| 1251 | switch (cmd) { |
| 1252 | case IPC_INFO: { |
| 1253 | struct shminfo64 shminfo; |
| 1254 | err = shmctl_ipc_info(ns, &shminfo); |
| 1255 | if (err < 0) |
| 1256 | return err; |
| 1257 | if (copy_compat_shminfo_to_user(uptr, &shminfo, version)) |
| 1258 | err = -EFAULT; |
| 1259 | return err; |
| 1260 | } |
| 1261 | case SHM_INFO: { |
| 1262 | struct shm_info shm_info; |
| 1263 | err = shmctl_shm_info(ns, &shm_info); |
| 1264 | if (err < 0) |
| 1265 | return err; |
| 1266 | if (put_compat_shm_info(&shm_info, uptr)) |
| 1267 | err = -EFAULT; |
| 1268 | return err; |
| 1269 | } |
| 1270 | case IPC_STAT: |
| 1271 | case SHM_STAT: |
| 1272 | err = shmctl_stat(ns, shmid, cmd, &sem64); |
| 1273 | if (err < 0) |
| 1274 | return err; |
Will Deacon | 58aff0a | 2017-09-18 17:47:38 +0100 | [diff] [blame] | 1275 | if (copy_compat_shmid_to_user(uptr, &sem64, version)) |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1276 | err = -EFAULT; |
| 1277 | return err; |
| 1278 | |
| 1279 | case IPC_SET: |
| 1280 | if (copy_compat_shmid_from_user(&sem64, uptr, version)) |
| 1281 | return -EFAULT; |
| 1282 | /* fallthru */ |
| 1283 | case IPC_RMID: |
| 1284 | return shmctl_down(ns, shmid, cmd, &sem64); |
| 1285 | case SHM_LOCK: |
| 1286 | case SHM_UNLOCK: |
| 1287 | return shmctl_do_lock(ns, shmid, cmd); |
| 1288 | break; |
| 1289 | default: |
| 1290 | return -EINVAL; |
| 1291 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1292 | return err; |
| 1293 | } |
Al Viro | 553f770 | 2017-07-08 22:52:47 -0400 | [diff] [blame] | 1294 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1295 | |
| 1296 | /* |
| 1297 | * Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists. |
| 1298 | * |
| 1299 | * NOTE! Despite the name, this is NOT a direct system call entrypoint. The |
| 1300 | * "raddr" thing points to kernel space, and there has to be a wrapper around |
| 1301 | * this. |
| 1302 | */ |
Davidlohr Bueso | 95e91b8 | 2017-02-27 14:28:24 -0800 | [diff] [blame] | 1303 | long do_shmat(int shmid, char __user *shmaddr, int shmflg, |
| 1304 | ulong *raddr, unsigned long shmlba) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1305 | { |
| 1306 | struct shmid_kernel *shp; |
Davidlohr Bueso | f0cb880 | 2017-05-08 15:57:03 -0700 | [diff] [blame] | 1307 | unsigned long addr = (unsigned long)shmaddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1308 | unsigned long size; |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 1309 | struct file *file; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1310 | int err; |
Davidlohr Bueso | f0cb880 | 2017-05-08 15:57:03 -0700 | [diff] [blame] | 1311 | unsigned long flags = MAP_SHARED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1312 | unsigned long prot; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1313 | int acc_mode; |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 1314 | struct ipc_namespace *ns; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1315 | struct shm_file_data *sfd; |
| 1316 | struct path path; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 1317 | fmode_t f_mode; |
Michel Lespinasse | 41badc1 | 2013-02-22 16:32:47 -0800 | [diff] [blame] | 1318 | unsigned long populate = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1319 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1320 | err = -EINVAL; |
| 1321 | if (shmid < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1322 | goto out; |
Davidlohr Bueso | f0cb880 | 2017-05-08 15:57:03 -0700 | [diff] [blame] | 1323 | |
| 1324 | if (addr) { |
Will Deacon | 079a96a | 2012-07-30 14:42:38 -0700 | [diff] [blame] | 1325 | if (addr & (shmlba - 1)) { |
Davidlohr Bueso | 95e91b8 | 2017-02-27 14:28:24 -0800 | [diff] [blame] | 1326 | /* |
| 1327 | * Round down to the nearest multiple of shmlba. |
| 1328 | * For sane do_mmap_pgoff() parameters, avoid |
| 1329 | * round downs that trigger nil-page and MAP_FIXED. |
| 1330 | */ |
| 1331 | if ((shmflg & SHM_RND) && addr >= shmlba) |
| 1332 | addr &= ~(shmlba - 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1333 | else |
| 1334 | #ifndef __ARCH_FORCE_SHMLBA |
| 1335 | if (addr & ~PAGE_MASK) |
| 1336 | #endif |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1337 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1338 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1339 | |
Davidlohr Bueso | f0cb880 | 2017-05-08 15:57:03 -0700 | [diff] [blame] | 1340 | flags |= MAP_FIXED; |
| 1341 | } else if ((shmflg & SHM_REMAP)) |
| 1342 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1343 | |
| 1344 | if (shmflg & SHM_RDONLY) { |
| 1345 | prot = PROT_READ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1346 | acc_mode = S_IRUGO; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1347 | f_mode = FMODE_READ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1348 | } else { |
| 1349 | prot = PROT_READ | PROT_WRITE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1350 | acc_mode = S_IRUGO | S_IWUGO; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1351 | f_mode = FMODE_READ | FMODE_WRITE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1352 | } |
| 1353 | if (shmflg & SHM_EXEC) { |
| 1354 | prot |= PROT_EXEC; |
| 1355 | acc_mode |= S_IXUGO; |
| 1356 | } |
| 1357 | |
| 1358 | /* |
| 1359 | * We cannot rely on the fs check since SYSV IPC does have an |
| 1360 | * additional creator id... |
| 1361 | */ |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 1362 | ns = current->nsproxy->ipc_ns; |
Davidlohr Bueso | c2c737a | 2013-09-11 14:26:23 -0700 | [diff] [blame] | 1363 | rcu_read_lock(); |
| 1364 | shp = shm_obtain_object_check(ns, shmid); |
Nadia Derbey | 023a535 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 1365 | if (IS_ERR(shp)) { |
| 1366 | err = PTR_ERR(shp); |
Davidlohr Bueso | c2c737a | 2013-09-11 14:26:23 -0700 | [diff] [blame] | 1367 | goto out_unlock; |
Nadia Derbey | 023a535 | 2007-10-18 23:40:51 -0700 | [diff] [blame] | 1368 | } |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1369 | |
| 1370 | err = -EACCES; |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 1371 | if (ipcperms(ns, &shp->shm_perm, acc_mode)) |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1372 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1373 | |
Eric W. Biederman | 7191adf | 2018-03-22 21:08:27 -0500 | [diff] [blame] | 1374 | err = security_shm_shmat(&shp->shm_perm, shmaddr, shmflg); |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1375 | if (err) |
| 1376 | goto out_unlock; |
| 1377 | |
Davidlohr Bueso | c2c737a | 2013-09-11 14:26:23 -0700 | [diff] [blame] | 1378 | ipc_lock_object(&shp->shm_perm); |
Greg Thelen | a399b29 | 2013-11-21 14:32:00 -0800 | [diff] [blame] | 1379 | |
| 1380 | /* check if shm_destroy() is tearing down shp */ |
Rafael Aquini | 0f3d2b0 | 2014-01-27 17:07:01 -0800 | [diff] [blame] | 1381 | if (!ipc_valid_object(&shp->shm_perm)) { |
Greg Thelen | a399b29 | 2013-11-21 14:32:00 -0800 | [diff] [blame] | 1382 | ipc_unlock_object(&shp->shm_perm); |
| 1383 | err = -EIDRM; |
| 1384 | goto out_unlock; |
| 1385 | } |
| 1386 | |
Al Viro | 2c48b9c | 2009-08-09 00:52:35 +0400 | [diff] [blame] | 1387 | path = shp->shm_file->f_path; |
| 1388 | path_get(&path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1389 | shp->shm_nattch++; |
David Howells | 75c3cfa | 2015-03-17 22:26:12 +0000 | [diff] [blame] | 1390 | size = i_size_read(d_inode(path.dentry)); |
Davidlohr Bueso | c2c737a | 2013-09-11 14:26:23 -0700 | [diff] [blame] | 1391 | ipc_unlock_object(&shp->shm_perm); |
| 1392 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1393 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1394 | err = -ENOMEM; |
| 1395 | sfd = kzalloc(sizeof(*sfd), GFP_KERNEL); |
Davidlohr Bueso | f42569b | 2013-09-11 14:26:22 -0700 | [diff] [blame] | 1396 | if (!sfd) { |
| 1397 | path_put(&path); |
| 1398 | goto out_nattch; |
| 1399 | } |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1400 | |
Al Viro | 2c48b9c | 2009-08-09 00:52:35 +0400 | [diff] [blame] | 1401 | file = alloc_file(&path, f_mode, |
| 1402 | is_file_hugepages(shp->shm_file) ? |
Al Viro | c4caa77 | 2009-11-30 08:38:43 -0500 | [diff] [blame] | 1403 | &shm_file_operations_huge : |
| 1404 | &shm_file_operations); |
Anatol Pomozov | 39b65252 | 2012-09-12 20:11:55 -0700 | [diff] [blame] | 1405 | err = PTR_ERR(file); |
Davidlohr Bueso | f42569b | 2013-09-11 14:26:22 -0700 | [diff] [blame] | 1406 | if (IS_ERR(file)) { |
| 1407 | kfree(sfd); |
| 1408 | path_put(&path); |
| 1409 | goto out_nattch; |
| 1410 | } |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1411 | |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1412 | file->private_data = sfd; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1413 | file->f_mapping = shp->shm_file->f_mapping; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 1414 | sfd->id = shp->shm_perm.id; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1415 | sfd->ns = get_ipc_ns(ns); |
| 1416 | sfd->file = shp->shm_file; |
| 1417 | sfd->vm_ops = NULL; |
| 1418 | |
Al Viro | 8b3ec68 | 2012-05-30 17:11:23 -0400 | [diff] [blame] | 1419 | err = security_mmap_file(file, prot, flags); |
| 1420 | if (err) |
| 1421 | goto out_fput; |
| 1422 | |
Michal Hocko | 91f4f94 | 2016-05-23 16:25:51 -0700 | [diff] [blame] | 1423 | if (down_write_killable(¤t->mm->mmap_sem)) { |
| 1424 | err = -EINTR; |
| 1425 | goto out_fput; |
| 1426 | } |
| 1427 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1428 | if (addr && !(shmflg & SHM_REMAP)) { |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1429 | err = -EINVAL; |
Manfred Spraul | 247a8ce | 2014-06-06 14:37:38 -0700 | [diff] [blame] | 1430 | if (addr + size < addr) |
| 1431 | goto invalid; |
| 1432 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1433 | if (find_vma_intersection(current->mm, addr, addr + size)) |
| 1434 | goto invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1435 | } |
Davidlohr Bueso | f42569b | 2013-09-11 14:26:22 -0700 | [diff] [blame] | 1436 | |
Mike Rapoport | 897ab3e | 2017-02-24 14:58:22 -0800 | [diff] [blame] | 1437 | addr = do_mmap_pgoff(file, addr, size, prot, flags, 0, &populate, NULL); |
Michel Lespinasse | bebeb3d | 2013-02-22 16:32:37 -0800 | [diff] [blame] | 1438 | *raddr = addr; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1439 | err = 0; |
Michel Lespinasse | bebeb3d | 2013-02-22 16:32:37 -0800 | [diff] [blame] | 1440 | if (IS_ERR_VALUE(addr)) |
| 1441 | err = (long)addr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1442 | invalid: |
| 1443 | up_write(¤t->mm->mmap_sem); |
Michel Lespinasse | bebeb3d | 2013-02-22 16:32:37 -0800 | [diff] [blame] | 1444 | if (populate) |
Michel Lespinasse | 41badc1 | 2013-02-22 16:32:47 -0800 | [diff] [blame] | 1445 | mm_populate(addr, populate); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1446 | |
Al Viro | 8b3ec68 | 2012-05-30 17:11:23 -0400 | [diff] [blame] | 1447 | out_fput: |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1448 | fput(file); |
| 1449 | |
| 1450 | out_nattch: |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 1451 | down_write(&shm_ids(ns).rwsem); |
Nadia Derbey | 00c2bf8 | 2008-07-25 01:48:03 -0700 | [diff] [blame] | 1452 | shp = shm_lock(ns, shmid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1453 | shp->shm_nattch--; |
Vasiliy Kulikov | b34a6b1 | 2011-07-26 16:08:48 -0700 | [diff] [blame] | 1454 | if (shm_may_destroy(ns, shp)) |
Kirill Korotaev | 4e98231 | 2006-10-02 02:18:22 -0700 | [diff] [blame] | 1455 | shm_destroy(ns, shp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1456 | else |
| 1457 | shm_unlock(shp); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 1458 | up_write(&shm_ids(ns).rwsem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1459 | return err; |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1460 | |
| 1461 | out_unlock: |
Davidlohr Bueso | c2c737a | 2013-09-11 14:26:23 -0700 | [diff] [blame] | 1462 | rcu_read_unlock(); |
Davidlohr Bueso | f42569b | 2013-09-11 14:26:22 -0700 | [diff] [blame] | 1463 | out: |
| 1464 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1465 | } |
| 1466 | |
Heiko Carstens | d5460c9 | 2009-01-14 14:14:27 +0100 | [diff] [blame] | 1467 | SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg) |
Stephen Rothwell | 7d87e14c | 2005-05-01 08:59:12 -0700 | [diff] [blame] | 1468 | { |
| 1469 | unsigned long ret; |
| 1470 | long err; |
| 1471 | |
Will Deacon | 079a96a | 2012-07-30 14:42:38 -0700 | [diff] [blame] | 1472 | err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA); |
Stephen Rothwell | 7d87e14c | 2005-05-01 08:59:12 -0700 | [diff] [blame] | 1473 | if (err) |
| 1474 | return err; |
| 1475 | force_successful_syscall_return(); |
| 1476 | return (long)ret; |
| 1477 | } |
| 1478 | |
Al Viro | a78ee9e | 2017-07-09 10:38:28 -0400 | [diff] [blame] | 1479 | #ifdef CONFIG_COMPAT |
| 1480 | |
| 1481 | #ifndef COMPAT_SHMLBA |
| 1482 | #define COMPAT_SHMLBA SHMLBA |
| 1483 | #endif |
| 1484 | |
| 1485 | COMPAT_SYSCALL_DEFINE3(shmat, int, shmid, compat_uptr_t, shmaddr, int, shmflg) |
| 1486 | { |
| 1487 | unsigned long ret; |
| 1488 | long err; |
| 1489 | |
| 1490 | err = do_shmat(shmid, compat_ptr(shmaddr), shmflg, &ret, COMPAT_SHMLBA); |
| 1491 | if (err) |
| 1492 | return err; |
| 1493 | force_successful_syscall_return(); |
| 1494 | return (long)ret; |
| 1495 | } |
| 1496 | #endif |
| 1497 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1498 | /* |
| 1499 | * detach and kill segment if marked destroyed. |
| 1500 | * The work is done in shm_close. |
| 1501 | */ |
Heiko Carstens | d5460c9 | 2009-01-14 14:14:27 +0100 | [diff] [blame] | 1502 | SYSCALL_DEFINE1(shmdt, char __user *, shmaddr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1503 | { |
| 1504 | struct mm_struct *mm = current->mm; |
Mike Frysinger | 586c7e6 | 2009-06-09 16:26:23 -0700 | [diff] [blame] | 1505 | struct vm_area_struct *vma; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1506 | unsigned long addr = (unsigned long)shmaddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1507 | int retval = -EINVAL; |
Mike Frysinger | 586c7e6 | 2009-06-09 16:26:23 -0700 | [diff] [blame] | 1508 | #ifdef CONFIG_MMU |
| 1509 | loff_t size = 0; |
Dave Hansen | d3c9790 | 2014-12-12 16:58:19 -0800 | [diff] [blame] | 1510 | struct file *file; |
Mike Frysinger | 586c7e6 | 2009-06-09 16:26:23 -0700 | [diff] [blame] | 1511 | struct vm_area_struct *next; |
| 1512 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1513 | |
Hugh Dickins | df1e2fb | 2006-03-24 03:18:06 -0800 | [diff] [blame] | 1514 | if (addr & ~PAGE_MASK) |
| 1515 | return retval; |
| 1516 | |
Michal Hocko | 91f4f94 | 2016-05-23 16:25:51 -0700 | [diff] [blame] | 1517 | if (down_write_killable(&mm->mmap_sem)) |
| 1518 | return -EINTR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | |
| 1520 | /* |
| 1521 | * This function tries to be smart and unmap shm segments that |
| 1522 | * were modified by partial mlock or munmap calls: |
| 1523 | * - It first determines the size of the shm segment that should be |
| 1524 | * unmapped: It searches for a vma that is backed by shm and that |
| 1525 | * started at address shmaddr. It records it's size and then unmaps |
| 1526 | * it. |
| 1527 | * - Then it unmaps all shm vmas that started at shmaddr and that |
Dave Hansen | d3c9790 | 2014-12-12 16:58:19 -0800 | [diff] [blame] | 1528 | * are within the initially determined size and that are from the |
| 1529 | * same shm segment from which we determined the size. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1530 | * Errors from do_munmap are ignored: the function only fails if |
| 1531 | * it's called with invalid parameters or if it's called to unmap |
| 1532 | * a part of a vma. Both calls in this function are for full vmas, |
| 1533 | * the parameters are directly copied from the vma itself and always |
| 1534 | * valid - therefore do_munmap cannot fail. (famous last words?) |
| 1535 | */ |
| 1536 | /* |
| 1537 | * If it had been mremap()'d, the starting address would not |
| 1538 | * match the usual checks anyway. So assume all vma's are |
| 1539 | * above the starting address given. |
| 1540 | */ |
| 1541 | vma = find_vma(mm, addr); |
| 1542 | |
David Howells | 8feae13 | 2009-01-08 12:04:47 +0000 | [diff] [blame] | 1543 | #ifdef CONFIG_MMU |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1544 | while (vma) { |
| 1545 | next = vma->vm_next; |
| 1546 | |
| 1547 | /* |
| 1548 | * Check if the starting address would match, i.e. it's |
| 1549 | * a fragment created by mprotect() and/or munmap(), or it |
| 1550 | * otherwise it starts at this address with no hassles. |
| 1551 | */ |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1552 | if ((vma->vm_ops == &shm_vm_ops) && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1553 | (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) { |
| 1554 | |
Dave Hansen | d3c9790 | 2014-12-12 16:58:19 -0800 | [diff] [blame] | 1555 | /* |
| 1556 | * Record the file of the shm segment being |
| 1557 | * unmapped. With mremap(), someone could place |
| 1558 | * page from another segment but with equal offsets |
| 1559 | * in the range we are unmapping. |
| 1560 | */ |
| 1561 | file = vma->vm_file; |
Dave Hansen | 07a46ed | 2014-12-12 16:58:22 -0800 | [diff] [blame] | 1562 | size = i_size_read(file_inode(vma->vm_file)); |
Mike Rapoport | 897ab3e | 2017-02-24 14:58:22 -0800 | [diff] [blame] | 1563 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1564 | /* |
| 1565 | * We discovered the size of the shm segment, so |
| 1566 | * break out of here and fall through to the next |
| 1567 | * loop that uses the size information to stop |
| 1568 | * searching for matching vma's. |
| 1569 | */ |
| 1570 | retval = 0; |
| 1571 | vma = next; |
| 1572 | break; |
| 1573 | } |
| 1574 | vma = next; |
| 1575 | } |
| 1576 | |
| 1577 | /* |
| 1578 | * We need look no further than the maximum address a fragment |
| 1579 | * could possibly have landed at. Also cast things to loff_t to |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 1580 | * prevent overflows and make comparisons vs. equal-width types. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1581 | */ |
KAMEZAWA Hiroyuki | 8e36709 | 2006-02-10 01:51:12 -0800 | [diff] [blame] | 1582 | size = PAGE_ALIGN(size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1583 | while (vma && (loff_t)(vma->vm_end - addr) <= size) { |
| 1584 | next = vma->vm_next; |
| 1585 | |
| 1586 | /* finding a matching vma now does not alter retval */ |
Eric W. Biederman | bc56bba | 2007-02-20 13:57:53 -0800 | [diff] [blame] | 1587 | if ((vma->vm_ops == &shm_vm_ops) && |
Dave Hansen | d3c9790 | 2014-12-12 16:58:19 -0800 | [diff] [blame] | 1588 | ((vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) && |
| 1589 | (vma->vm_file == file)) |
Mike Rapoport | 897ab3e | 2017-02-24 14:58:22 -0800 | [diff] [blame] | 1590 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1591 | vma = next; |
| 1592 | } |
| 1593 | |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 1594 | #else /* CONFIG_MMU */ |
David Howells | 8feae13 | 2009-01-08 12:04:47 +0000 | [diff] [blame] | 1595 | /* under NOMMU conditions, the exact address to be destroyed must be |
Shailesh Pandey | 63980c8 | 2016-12-14 15:06:10 -0800 | [diff] [blame] | 1596 | * given |
| 1597 | */ |
Davidlohr Bueso | 530fcd16 | 2013-09-11 14:26:28 -0700 | [diff] [blame] | 1598 | if (vma && vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) { |
Mike Rapoport | 897ab3e | 2017-02-24 14:58:22 -0800 | [diff] [blame] | 1599 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); |
David Howells | 8feae13 | 2009-01-08 12:04:47 +0000 | [diff] [blame] | 1600 | retval = 0; |
| 1601 | } |
| 1602 | |
| 1603 | #endif |
| 1604 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1605 | up_write(&mm->mmap_sem); |
| 1606 | return retval; |
| 1607 | } |
| 1608 | |
| 1609 | #ifdef CONFIG_PROC_FS |
Mike Waychison | 19b4946 | 2005-09-06 15:17:10 -0700 | [diff] [blame] | 1610 | static int sysvipc_shm_proc_show(struct seq_file *s, void *it) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1611 | { |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 1612 | struct pid_namespace *pid_ns = ipc_seq_pid_ns(s); |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 1613 | struct user_namespace *user_ns = seq_user_ns(s); |
Kees Cook | ade9f91 | 2017-08-02 13:32:21 -0700 | [diff] [blame] | 1614 | struct kern_ipc_perm *ipcp = it; |
| 1615 | struct shmid_kernel *shp; |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 1616 | unsigned long rss = 0, swp = 0; |
| 1617 | |
Kees Cook | ade9f91 | 2017-08-02 13:32:21 -0700 | [diff] [blame] | 1618 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); |
Helge Deller | b795218 | 2010-10-27 15:34:16 -0700 | [diff] [blame] | 1619 | shm_add_rss_swap(shp, &rss, &swp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1620 | |
Paul Menage | 6c82681 | 2008-06-12 15:21:49 -0700 | [diff] [blame] | 1621 | #if BITS_PER_LONG <= 32 |
| 1622 | #define SIZE_SPEC "%10lu" |
| 1623 | #else |
| 1624 | #define SIZE_SPEC "%21lu" |
| 1625 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1626 | |
Joe Perches | 7f032d6 | 2015-04-15 16:17:54 -0700 | [diff] [blame] | 1627 | seq_printf(s, |
| 1628 | "%10d %10d %4o " SIZE_SPEC " %5u %5u " |
Deepa Dinamani | 7ff2819 | 2017-08-02 19:51:14 -0700 | [diff] [blame] | 1629 | "%5lu %5u %5u %5u %5u %10llu %10llu %10llu " |
Joe Perches | 7f032d6 | 2015-04-15 16:17:54 -0700 | [diff] [blame] | 1630 | SIZE_SPEC " " SIZE_SPEC "\n", |
| 1631 | shp->shm_perm.key, |
| 1632 | shp->shm_perm.id, |
| 1633 | shp->shm_perm.mode, |
| 1634 | shp->shm_segsz, |
Eric W. Biederman | 98f929b1 | 2018-03-23 00:29:57 -0500 | [diff] [blame^] | 1635 | pid_nr_ns(shp->shm_cprid, pid_ns), |
| 1636 | pid_nr_ns(shp->shm_lprid, pid_ns), |
Joe Perches | 7f032d6 | 2015-04-15 16:17:54 -0700 | [diff] [blame] | 1637 | shp->shm_nattch, |
| 1638 | from_kuid_munged(user_ns, shp->shm_perm.uid), |
| 1639 | from_kgid_munged(user_ns, shp->shm_perm.gid), |
| 1640 | from_kuid_munged(user_ns, shp->shm_perm.cuid), |
| 1641 | from_kgid_munged(user_ns, shp->shm_perm.cgid), |
| 1642 | shp->shm_atim, |
| 1643 | shp->shm_dtim, |
| 1644 | shp->shm_ctim, |
| 1645 | rss * PAGE_SIZE, |
| 1646 | swp * PAGE_SIZE); |
| 1647 | |
| 1648 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1649 | } |
| 1650 | #endif |