| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/fs/stat.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| */ |
| |
| #include <linux/blkdev.h> |
| #include <linux/export.h> |
| #include <linux/mm.h> |
| #include <linux/errno.h> |
| #include <linux/file.h> |
| #include <linux/highuid.h> |
| #include <linux/fs.h> |
| #include <linux/namei.h> |
| #include <linux/security.h> |
| #include <linux/cred.h> |
| #include <linux/syscalls.h> |
| #include <linux/pagemap.h> |
| #include <linux/compat.h> |
| #include <linux/iversion.h> |
| |
| #include <linux/uaccess.h> |
| #include <asm/unistd.h> |
| |
| #include "internal.h" |
| #include "mount.h" |
| |
| /** |
| * fill_mg_cmtime - Fill in the mtime and ctime and flag ctime as QUERIED |
| * @stat: where to store the resulting values |
| * @request_mask: STATX_* values requested |
| * @inode: inode from which to grab the c/mtime |
| * |
| * Given @inode, grab the ctime and mtime out if it and store the result |
| * in @stat. When fetching the value, flag it as queried so the next write |
| * will use a fine-grained timestamp. |
| */ |
| void fill_mg_cmtime(struct kstat *stat, u32 request_mask, struct inode *inode) |
| { |
| atomic_long_t *pnsec = (atomic_long_t *)&inode->__i_ctime.tv_nsec; |
| |
| /* If neither time was requested, then don't report them */ |
| if (!(request_mask & (STATX_CTIME|STATX_MTIME))) { |
| stat->result_mask &= ~(STATX_CTIME|STATX_MTIME); |
| return; |
| } |
| |
| stat->mtime = inode->i_mtime; |
| stat->ctime.tv_sec = inode->__i_ctime.tv_sec; |
| /* |
| * Atomically set the QUERIED flag and fetch the new value with |
| * the flag masked off. |
| */ |
| stat->ctime.tv_nsec = atomic_long_fetch_or(I_CTIME_QUERIED, pnsec) & |
| ~I_CTIME_QUERIED; |
| } |
| EXPORT_SYMBOL(fill_mg_cmtime); |
| |
| /** |
| * generic_fillattr - Fill in the basic attributes from the inode struct |
| * @idmap: idmap of the mount the inode was found from |
| * @request_mask: statx request_mask |
| * @inode: Inode to use as the source |
| * @stat: Where to fill in the attributes |
| * |
| * Fill in the basic attributes in the kstat structure from data that's to be |
| * found on the VFS inode structure. This is the default if no getattr inode |
| * operation is supplied. |
| * |
| * If the inode has been found through an idmapped mount the idmap of |
| * the vfsmount must be passed through @idmap. This function will then |
| * take care to map the inode according to @idmap before filling in the |
| * uid and gid filds. On non-idmapped mounts or if permission checking is to be |
| * performed on the raw inode simply passs @nop_mnt_idmap. |
| */ |
| void generic_fillattr(struct mnt_idmap *idmap, u32 request_mask, |
| struct inode *inode, struct kstat *stat) |
| { |
| vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode); |
| vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode); |
| |
| stat->dev = inode->i_sb->s_dev; |
| stat->ino = inode->i_ino; |
| stat->mode = inode->i_mode; |
| stat->nlink = inode->i_nlink; |
| stat->uid = vfsuid_into_kuid(vfsuid); |
| stat->gid = vfsgid_into_kgid(vfsgid); |
| stat->rdev = inode->i_rdev; |
| stat->size = i_size_read(inode); |
| stat->atime = inode->i_atime; |
| |
| if (is_mgtime(inode)) { |
| fill_mg_cmtime(stat, request_mask, inode); |
| } else { |
| stat->mtime = inode->i_mtime; |
| stat->ctime = inode_get_ctime(inode); |
| } |
| |
| stat->blksize = i_blocksize(inode); |
| stat->blocks = inode->i_blocks; |
| |
| if ((request_mask & STATX_CHANGE_COOKIE) && IS_I_VERSION(inode)) { |
| stat->result_mask |= STATX_CHANGE_COOKIE; |
| stat->change_cookie = inode_query_iversion(inode); |
| } |
| |
| } |
| EXPORT_SYMBOL(generic_fillattr); |
| |
| /** |
| * generic_fill_statx_attr - Fill in the statx attributes from the inode flags |
| * @inode: Inode to use as the source |
| * @stat: Where to fill in the attribute flags |
| * |
| * Fill in the STATX_ATTR_* flags in the kstat structure for properties of the |
| * inode that are published on i_flags and enforced by the VFS. |
| */ |
| void generic_fill_statx_attr(struct inode *inode, struct kstat *stat) |
| { |
| if (inode->i_flags & S_IMMUTABLE) |
| stat->attributes |= STATX_ATTR_IMMUTABLE; |
| if (inode->i_flags & S_APPEND) |
| stat->attributes |= STATX_ATTR_APPEND; |
| stat->attributes_mask |= KSTAT_ATTR_VFS_FLAGS; |
| } |
| EXPORT_SYMBOL(generic_fill_statx_attr); |
| |
| /** |
| * vfs_getattr_nosec - getattr without security checks |
| * @path: file to get attributes from |
| * @stat: structure to return attributes in |
| * @request_mask: STATX_xxx flags indicating what the caller wants |
| * @query_flags: Query mode (AT_STATX_SYNC_TYPE) |
| * |
| * Get attributes without calling security_inode_getattr. |
| * |
| * Currently the only caller other than vfs_getattr is internal to the |
| * filehandle lookup code, which uses only the inode number and returns no |
| * attributes to any user. Any other code probably wants vfs_getattr. |
| */ |
| int vfs_getattr_nosec(const struct path *path, struct kstat *stat, |
| u32 request_mask, unsigned int query_flags) |
| { |
| struct mnt_idmap *idmap; |
| struct inode *inode = d_backing_inode(path->dentry); |
| |
| memset(stat, 0, sizeof(*stat)); |
| stat->result_mask |= STATX_BASIC_STATS; |
| query_flags &= AT_STATX_SYNC_TYPE; |
| |
| /* allow the fs to override these if it really wants to */ |
| /* SB_NOATIME means filesystem supplies dummy atime value */ |
| if (inode->i_sb->s_flags & SB_NOATIME) |
| stat->result_mask &= ~STATX_ATIME; |
| |
| /* |
| * Note: If you add another clause to set an attribute flag, please |
| * update attributes_mask below. |
| */ |
| if (IS_AUTOMOUNT(inode)) |
| stat->attributes |= STATX_ATTR_AUTOMOUNT; |
| |
| if (IS_DAX(inode)) |
| stat->attributes |= STATX_ATTR_DAX; |
| |
| stat->attributes_mask |= (STATX_ATTR_AUTOMOUNT | |
| STATX_ATTR_DAX); |
| |
| idmap = mnt_idmap(path->mnt); |
| if (inode->i_op->getattr) |
| return inode->i_op->getattr(idmap, path, stat, |
| request_mask, query_flags); |
| |
| generic_fillattr(idmap, request_mask, inode, stat); |
| return 0; |
| } |
| EXPORT_SYMBOL(vfs_getattr_nosec); |
| |
| /* |
| * vfs_getattr - Get the enhanced basic attributes of a file |
| * @path: The file of interest |
| * @stat: Where to return the statistics |
| * @request_mask: STATX_xxx flags indicating what the caller wants |
| * @query_flags: Query mode (AT_STATX_SYNC_TYPE) |
| * |
| * Ask the filesystem for a file's attributes. The caller must indicate in |
| * request_mask and query_flags to indicate what they want. |
| * |
| * If the file is remote, the filesystem can be forced to update the attributes |
| * from the backing store by passing AT_STATX_FORCE_SYNC in query_flags or can |
| * suppress the update by passing AT_STATX_DONT_SYNC. |
| * |
| * Bits must have been set in request_mask to indicate which attributes the |
| * caller wants retrieving. Any such attribute not requested may be returned |
| * anyway, but the value may be approximate, and, if remote, may not have been |
| * synchronised with the server. |
| * |
| * 0 will be returned on success, and a -ve error code if unsuccessful. |
| */ |
| int vfs_getattr(const struct path *path, struct kstat *stat, |
| u32 request_mask, unsigned int query_flags) |
| { |
| int retval; |
| |
| retval = security_inode_getattr(path); |
| if (retval) |
| return retval; |
| return vfs_getattr_nosec(path, stat, request_mask, query_flags); |
| } |
| EXPORT_SYMBOL(vfs_getattr); |
| |
| /** |
| * vfs_fstat - Get the basic attributes by file descriptor |
| * @fd: The file descriptor referring to the file of interest |
| * @stat: The result structure to fill in. |
| * |
| * This function is a wrapper around vfs_getattr(). The main difference is |
| * that it uses a file descriptor to determine the file location. |
| * |
| * 0 will be returned on success, and a -ve error code if unsuccessful. |
| */ |
| int vfs_fstat(int fd, struct kstat *stat) |
| { |
| struct fd f; |
| int error; |
| |
| f = fdget_raw(fd); |
| if (!f.file) |
| return -EBADF; |
| error = vfs_getattr(&f.file->f_path, stat, STATX_BASIC_STATS, 0); |
| fdput(f); |
| return error; |
| } |
| |
| int getname_statx_lookup_flags(int flags) |
| { |
| int lookup_flags = 0; |
| |
| if (!(flags & AT_SYMLINK_NOFOLLOW)) |
| lookup_flags |= LOOKUP_FOLLOW; |
| if (!(flags & AT_NO_AUTOMOUNT)) |
| lookup_flags |= LOOKUP_AUTOMOUNT; |
| if (flags & AT_EMPTY_PATH) |
| lookup_flags |= LOOKUP_EMPTY; |
| |
| return lookup_flags; |
| } |
| |
| /** |
| * vfs_statx - Get basic and extra attributes by filename |
| * @dfd: A file descriptor representing the base dir for a relative filename |
| * @filename: The name of the file of interest |
| * @flags: Flags to control the query |
| * @stat: The result structure to fill in. |
| * @request_mask: STATX_xxx flags indicating what the caller wants |
| * |
| * This function is a wrapper around vfs_getattr(). The main difference is |
| * that it uses a filename and base directory to determine the file location. |
| * Additionally, the use of AT_SYMLINK_NOFOLLOW in flags will prevent a symlink |
| * at the given name from being referenced. |
| * |
| * 0 will be returned on success, and a -ve error code if unsuccessful. |
| */ |
| static int vfs_statx(int dfd, struct filename *filename, int flags, |
| struct kstat *stat, u32 request_mask) |
| { |
| struct path path; |
| unsigned int lookup_flags = getname_statx_lookup_flags(flags); |
| int error; |
| |
| if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT | AT_EMPTY_PATH | |
| AT_STATX_SYNC_TYPE)) |
| return -EINVAL; |
| |
| retry: |
| error = filename_lookup(dfd, filename, lookup_flags, &path, NULL); |
| if (error) |
| goto out; |
| |
| error = vfs_getattr(&path, stat, request_mask, flags); |
| |
| stat->mnt_id = real_mount(path.mnt)->mnt_id; |
| stat->result_mask |= STATX_MNT_ID; |
| |
| if (path.mnt->mnt_root == path.dentry) |
| stat->attributes |= STATX_ATTR_MOUNT_ROOT; |
| stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT; |
| |
| /* Handle STATX_DIOALIGN for block devices. */ |
| if (request_mask & STATX_DIOALIGN) { |
| struct inode *inode = d_backing_inode(path.dentry); |
| |
| if (S_ISBLK(inode->i_mode)) |
| bdev_statx_dioalign(inode, stat); |
| } |
| |
| path_put(&path); |
| if (retry_estale(error, lookup_flags)) { |
| lookup_flags |= LOOKUP_REVAL; |
| goto retry; |
| } |
| out: |
| return error; |
| } |
| |
| int vfs_fstatat(int dfd, const char __user *filename, |
| struct kstat *stat, int flags) |
| { |
| int ret; |
| int statx_flags = flags | AT_NO_AUTOMOUNT; |
| struct filename *name; |
| |
| /* |
| * Work around glibc turning fstat() into fstatat(AT_EMPTY_PATH) |
| * |
| * If AT_EMPTY_PATH is set, we expect the common case to be that |
| * empty path, and avoid doing all the extra pathname work. |
| */ |
| if (dfd >= 0 && flags == AT_EMPTY_PATH) { |
| char c; |
| |
| ret = get_user(c, filename); |
| if (unlikely(ret)) |
| return ret; |
| |
| if (likely(!c)) |
| return vfs_fstat(dfd, stat); |
| } |
| |
| name = getname_flags(filename, getname_statx_lookup_flags(statx_flags), NULL); |
| ret = vfs_statx(dfd, name, statx_flags, stat, STATX_BASIC_STATS); |
| putname(name); |
| |
| return ret; |
| } |
| |
| #ifdef __ARCH_WANT_OLD_STAT |
| |
| /* |
| * For backward compatibility? Maybe this should be moved |
| * into arch/i386 instead? |
| */ |
| static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf) |
| { |
| static int warncount = 5; |
| struct __old_kernel_stat tmp; |
| |
| if (warncount > 0) { |
| warncount--; |
| printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n", |
| current->comm); |
| } else if (warncount < 0) { |
| /* it's laughable, but... */ |
| warncount = 0; |
| } |
| |
| memset(&tmp, 0, sizeof(struct __old_kernel_stat)); |
| tmp.st_dev = old_encode_dev(stat->dev); |
| tmp.st_ino = stat->ino; |
| if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
| return -EOVERFLOW; |
| tmp.st_mode = stat->mode; |
| tmp.st_nlink = stat->nlink; |
| if (tmp.st_nlink != stat->nlink) |
| return -EOVERFLOW; |
| SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); |
| SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); |
| tmp.st_rdev = old_encode_dev(stat->rdev); |
| #if BITS_PER_LONG == 32 |
| if (stat->size > MAX_NON_LFS) |
| return -EOVERFLOW; |
| #endif |
| tmp.st_size = stat->size; |
| tmp.st_atime = stat->atime.tv_sec; |
| tmp.st_mtime = stat->mtime.tv_sec; |
| tmp.st_ctime = stat->ctime.tv_sec; |
| return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; |
| } |
| |
| SYSCALL_DEFINE2(stat, const char __user *, filename, |
| struct __old_kernel_stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_stat(filename, &stat); |
| if (error) |
| return error; |
| |
| return cp_old_stat(&stat, statbuf); |
| } |
| |
| SYSCALL_DEFINE2(lstat, const char __user *, filename, |
| struct __old_kernel_stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_lstat(filename, &stat); |
| if (error) |
| return error; |
| |
| return cp_old_stat(&stat, statbuf); |
| } |
| |
| SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_fstat(fd, &stat); |
| |
| if (!error) |
| error = cp_old_stat(&stat, statbuf); |
| |
| return error; |
| } |
| |
| #endif /* __ARCH_WANT_OLD_STAT */ |
| |
| #ifdef __ARCH_WANT_NEW_STAT |
| |
| #ifndef INIT_STRUCT_STAT_PADDING |
| # define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st)) |
| #endif |
| |
| static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) |
| { |
| struct stat tmp; |
| |
| if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev)) |
| return -EOVERFLOW; |
| if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev)) |
| return -EOVERFLOW; |
| #if BITS_PER_LONG == 32 |
| if (stat->size > MAX_NON_LFS) |
| return -EOVERFLOW; |
| #endif |
| |
| INIT_STRUCT_STAT_PADDING(tmp); |
| tmp.st_dev = new_encode_dev(stat->dev); |
| tmp.st_ino = stat->ino; |
| if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
| return -EOVERFLOW; |
| tmp.st_mode = stat->mode; |
| tmp.st_nlink = stat->nlink; |
| if (tmp.st_nlink != stat->nlink) |
| return -EOVERFLOW; |
| SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); |
| SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); |
| tmp.st_rdev = new_encode_dev(stat->rdev); |
| tmp.st_size = stat->size; |
| tmp.st_atime = stat->atime.tv_sec; |
| tmp.st_mtime = stat->mtime.tv_sec; |
| tmp.st_ctime = stat->ctime.tv_sec; |
| #ifdef STAT_HAVE_NSEC |
| tmp.st_atime_nsec = stat->atime.tv_nsec; |
| tmp.st_mtime_nsec = stat->mtime.tv_nsec; |
| tmp.st_ctime_nsec = stat->ctime.tv_nsec; |
| #endif |
| tmp.st_blocks = stat->blocks; |
| tmp.st_blksize = stat->blksize; |
| return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; |
| } |
| |
| SYSCALL_DEFINE2(newstat, const char __user *, filename, |
| struct stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_stat(filename, &stat); |
| |
| if (error) |
| return error; |
| return cp_new_stat(&stat, statbuf); |
| } |
| |
| SYSCALL_DEFINE2(newlstat, const char __user *, filename, |
| struct stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_lstat(filename, &stat); |
| if (error) |
| return error; |
| |
| return cp_new_stat(&stat, statbuf); |
| } |
| |
| #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT) |
| SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename, |
| struct stat __user *, statbuf, int, flag) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_fstatat(dfd, filename, &stat, flag); |
| if (error) |
| return error; |
| return cp_new_stat(&stat, statbuf); |
| } |
| #endif |
| |
| SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_fstat(fd, &stat); |
| |
| if (!error) |
| error = cp_new_stat(&stat, statbuf); |
| |
| return error; |
| } |
| #endif |
| |
| static int do_readlinkat(int dfd, const char __user *pathname, |
| char __user *buf, int bufsiz) |
| { |
| struct path path; |
| int error; |
| int empty = 0; |
| unsigned int lookup_flags = LOOKUP_EMPTY; |
| |
| if (bufsiz <= 0) |
| return -EINVAL; |
| |
| retry: |
| error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty); |
| if (!error) { |
| struct inode *inode = d_backing_inode(path.dentry); |
| |
| error = empty ? -ENOENT : -EINVAL; |
| /* |
| * AFS mountpoints allow readlink(2) but are not symlinks |
| */ |
| if (d_is_symlink(path.dentry) || inode->i_op->readlink) { |
| error = security_inode_readlink(path.dentry); |
| if (!error) { |
| touch_atime(&path); |
| error = vfs_readlink(path.dentry, buf, bufsiz); |
| } |
| } |
| path_put(&path); |
| if (retry_estale(error, lookup_flags)) { |
| lookup_flags |= LOOKUP_REVAL; |
| goto retry; |
| } |
| } |
| return error; |
| } |
| |
| SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname, |
| char __user *, buf, int, bufsiz) |
| { |
| return do_readlinkat(dfd, pathname, buf, bufsiz); |
| } |
| |
| SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf, |
| int, bufsiz) |
| { |
| return do_readlinkat(AT_FDCWD, path, buf, bufsiz); |
| } |
| |
| |
| /* ---------- LFS-64 ----------- */ |
| #if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64) |
| |
| #ifndef INIT_STRUCT_STAT64_PADDING |
| # define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st)) |
| #endif |
| |
| static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf) |
| { |
| struct stat64 tmp; |
| |
| INIT_STRUCT_STAT64_PADDING(tmp); |
| #ifdef CONFIG_MIPS |
| /* mips has weird padding, so we don't get 64 bits there */ |
| tmp.st_dev = new_encode_dev(stat->dev); |
| tmp.st_rdev = new_encode_dev(stat->rdev); |
| #else |
| tmp.st_dev = huge_encode_dev(stat->dev); |
| tmp.st_rdev = huge_encode_dev(stat->rdev); |
| #endif |
| tmp.st_ino = stat->ino; |
| if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
| return -EOVERFLOW; |
| #ifdef STAT64_HAS_BROKEN_ST_INO |
| tmp.__st_ino = stat->ino; |
| #endif |
| tmp.st_mode = stat->mode; |
| tmp.st_nlink = stat->nlink; |
| tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid); |
| tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid); |
| tmp.st_atime = stat->atime.tv_sec; |
| tmp.st_atime_nsec = stat->atime.tv_nsec; |
| tmp.st_mtime = stat->mtime.tv_sec; |
| tmp.st_mtime_nsec = stat->mtime.tv_nsec; |
| tmp.st_ctime = stat->ctime.tv_sec; |
| tmp.st_ctime_nsec = stat->ctime.tv_nsec; |
| tmp.st_size = stat->size; |
| tmp.st_blocks = stat->blocks; |
| tmp.st_blksize = stat->blksize; |
| return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; |
| } |
| |
| SYSCALL_DEFINE2(stat64, const char __user *, filename, |
| struct stat64 __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_stat(filename, &stat); |
| |
| if (!error) |
| error = cp_new_stat64(&stat, statbuf); |
| |
| return error; |
| } |
| |
| SYSCALL_DEFINE2(lstat64, const char __user *, filename, |
| struct stat64 __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_lstat(filename, &stat); |
| |
| if (!error) |
| error = cp_new_stat64(&stat, statbuf); |
| |
| return error; |
| } |
| |
| SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_fstat(fd, &stat); |
| |
| if (!error) |
| error = cp_new_stat64(&stat, statbuf); |
| |
| return error; |
| } |
| |
| SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename, |
| struct stat64 __user *, statbuf, int, flag) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_fstatat(dfd, filename, &stat, flag); |
| if (error) |
| return error; |
| return cp_new_stat64(&stat, statbuf); |
| } |
| #endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */ |
| |
| static noinline_for_stack int |
| cp_statx(const struct kstat *stat, struct statx __user *buffer) |
| { |
| struct statx tmp; |
| |
| memset(&tmp, 0, sizeof(tmp)); |
| |
| /* STATX_CHANGE_COOKIE is kernel-only for now */ |
| tmp.stx_mask = stat->result_mask & ~STATX_CHANGE_COOKIE; |
| tmp.stx_blksize = stat->blksize; |
| /* STATX_ATTR_CHANGE_MONOTONIC is kernel-only for now */ |
| tmp.stx_attributes = stat->attributes & ~STATX_ATTR_CHANGE_MONOTONIC; |
| tmp.stx_nlink = stat->nlink; |
| tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid); |
| tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid); |
| tmp.stx_mode = stat->mode; |
| tmp.stx_ino = stat->ino; |
| tmp.stx_size = stat->size; |
| tmp.stx_blocks = stat->blocks; |
| tmp.stx_attributes_mask = stat->attributes_mask; |
| tmp.stx_atime.tv_sec = stat->atime.tv_sec; |
| tmp.stx_atime.tv_nsec = stat->atime.tv_nsec; |
| tmp.stx_btime.tv_sec = stat->btime.tv_sec; |
| tmp.stx_btime.tv_nsec = stat->btime.tv_nsec; |
| tmp.stx_ctime.tv_sec = stat->ctime.tv_sec; |
| tmp.stx_ctime.tv_nsec = stat->ctime.tv_nsec; |
| tmp.stx_mtime.tv_sec = stat->mtime.tv_sec; |
| tmp.stx_mtime.tv_nsec = stat->mtime.tv_nsec; |
| tmp.stx_rdev_major = MAJOR(stat->rdev); |
| tmp.stx_rdev_minor = MINOR(stat->rdev); |
| tmp.stx_dev_major = MAJOR(stat->dev); |
| tmp.stx_dev_minor = MINOR(stat->dev); |
| tmp.stx_mnt_id = stat->mnt_id; |
| tmp.stx_dio_mem_align = stat->dio_mem_align; |
| tmp.stx_dio_offset_align = stat->dio_offset_align; |
| |
| return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
| } |
| |
| int do_statx(int dfd, struct filename *filename, unsigned int flags, |
| unsigned int mask, struct statx __user *buffer) |
| { |
| struct kstat stat; |
| int error; |
| |
| if (mask & STATX__RESERVED) |
| return -EINVAL; |
| if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE) |
| return -EINVAL; |
| |
| /* STATX_CHANGE_COOKIE is kernel-only for now. Ignore requests |
| * from userland. |
| */ |
| mask &= ~STATX_CHANGE_COOKIE; |
| |
| error = vfs_statx(dfd, filename, flags, &stat, mask); |
| if (error) |
| return error; |
| |
| return cp_statx(&stat, buffer); |
| } |
| |
| /** |
| * sys_statx - System call to get enhanced stats |
| * @dfd: Base directory to pathwalk from *or* fd to stat. |
| * @filename: File to stat or "" with AT_EMPTY_PATH |
| * @flags: AT_* flags to control pathwalk. |
| * @mask: Parts of statx struct actually required. |
| * @buffer: Result buffer. |
| * |
| * Note that fstat() can be emulated by setting dfd to the fd of interest, |
| * supplying "" as the filename and setting AT_EMPTY_PATH in the flags. |
| */ |
| SYSCALL_DEFINE5(statx, |
| int, dfd, const char __user *, filename, unsigned, flags, |
| unsigned int, mask, |
| struct statx __user *, buffer) |
| { |
| int ret; |
| struct filename *name; |
| |
| name = getname_flags(filename, getname_statx_lookup_flags(flags), NULL); |
| ret = do_statx(dfd, name, flags, mask, buffer); |
| putname(name); |
| |
| return ret; |
| } |
| |
| #if defined(CONFIG_COMPAT) && defined(__ARCH_WANT_COMPAT_STAT) |
| static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf) |
| { |
| struct compat_stat tmp; |
| |
| if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev)) |
| return -EOVERFLOW; |
| if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev)) |
| return -EOVERFLOW; |
| |
| memset(&tmp, 0, sizeof(tmp)); |
| tmp.st_dev = new_encode_dev(stat->dev); |
| tmp.st_ino = stat->ino; |
| if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
| return -EOVERFLOW; |
| tmp.st_mode = stat->mode; |
| tmp.st_nlink = stat->nlink; |
| if (tmp.st_nlink != stat->nlink) |
| return -EOVERFLOW; |
| SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); |
| SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); |
| tmp.st_rdev = new_encode_dev(stat->rdev); |
| if ((u64) stat->size > MAX_NON_LFS) |
| return -EOVERFLOW; |
| tmp.st_size = stat->size; |
| tmp.st_atime = stat->atime.tv_sec; |
| tmp.st_atime_nsec = stat->atime.tv_nsec; |
| tmp.st_mtime = stat->mtime.tv_sec; |
| tmp.st_mtime_nsec = stat->mtime.tv_nsec; |
| tmp.st_ctime = stat->ctime.tv_sec; |
| tmp.st_ctime_nsec = stat->ctime.tv_nsec; |
| tmp.st_blocks = stat->blocks; |
| tmp.st_blksize = stat->blksize; |
| return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
| } |
| |
| COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename, |
| struct compat_stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_stat(filename, &stat); |
| if (error) |
| return error; |
| return cp_compat_stat(&stat, statbuf); |
| } |
| |
| COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename, |
| struct compat_stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_lstat(filename, &stat); |
| if (error) |
| return error; |
| return cp_compat_stat(&stat, statbuf); |
| } |
| |
| #ifndef __ARCH_WANT_STAT64 |
| COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd, |
| const char __user *, filename, |
| struct compat_stat __user *, statbuf, int, flag) |
| { |
| struct kstat stat; |
| int error; |
| |
| error = vfs_fstatat(dfd, filename, &stat, flag); |
| if (error) |
| return error; |
| return cp_compat_stat(&stat, statbuf); |
| } |
| #endif |
| |
| COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd, |
| struct compat_stat __user *, statbuf) |
| { |
| struct kstat stat; |
| int error = vfs_fstat(fd, &stat); |
| |
| if (!error) |
| error = cp_compat_stat(&stat, statbuf); |
| return error; |
| } |
| #endif |
| |
| /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */ |
| void __inode_add_bytes(struct inode *inode, loff_t bytes) |
| { |
| inode->i_blocks += bytes >> 9; |
| bytes &= 511; |
| inode->i_bytes += bytes; |
| if (inode->i_bytes >= 512) { |
| inode->i_blocks++; |
| inode->i_bytes -= 512; |
| } |
| } |
| EXPORT_SYMBOL(__inode_add_bytes); |
| |
| void inode_add_bytes(struct inode *inode, loff_t bytes) |
| { |
| spin_lock(&inode->i_lock); |
| __inode_add_bytes(inode, bytes); |
| spin_unlock(&inode->i_lock); |
| } |
| |
| EXPORT_SYMBOL(inode_add_bytes); |
| |
| void __inode_sub_bytes(struct inode *inode, loff_t bytes) |
| { |
| inode->i_blocks -= bytes >> 9; |
| bytes &= 511; |
| if (inode->i_bytes < bytes) { |
| inode->i_blocks--; |
| inode->i_bytes += 512; |
| } |
| inode->i_bytes -= bytes; |
| } |
| |
| EXPORT_SYMBOL(__inode_sub_bytes); |
| |
| void inode_sub_bytes(struct inode *inode, loff_t bytes) |
| { |
| spin_lock(&inode->i_lock); |
| __inode_sub_bytes(inode, bytes); |
| spin_unlock(&inode->i_lock); |
| } |
| |
| EXPORT_SYMBOL(inode_sub_bytes); |
| |
| loff_t inode_get_bytes(struct inode *inode) |
| { |
| loff_t ret; |
| |
| spin_lock(&inode->i_lock); |
| ret = __inode_get_bytes(inode); |
| spin_unlock(&inode->i_lock); |
| return ret; |
| } |
| |
| EXPORT_SYMBOL(inode_get_bytes); |
| |
| void inode_set_bytes(struct inode *inode, loff_t bytes) |
| { |
| /* Caller is here responsible for sufficient locking |
| * (ie. inode->i_lock) */ |
| inode->i_blocks = bytes >> 9; |
| inode->i_bytes = bytes & 511; |
| } |
| |
| EXPORT_SYMBOL(inode_set_bytes); |