Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/fs/stat.c | |
4 | * | |
5 | * Copyright (C) 1991, 1992 Linus Torvalds | |
6 | */ | |
7 | ||
2d985f8c | 8 | #include <linux/blkdev.h> |
630d9c47 | 9 | #include <linux/export.h> |
1da177e4 LT |
10 | #include <linux/mm.h> |
11 | #include <linux/errno.h> | |
12 | #include <linux/file.h> | |
1da177e4 LT |
13 | #include <linux/highuid.h> |
14 | #include <linux/fs.h> | |
15 | #include <linux/namei.h> | |
16 | #include <linux/security.h> | |
5b825c3a | 17 | #include <linux/cred.h> |
1da177e4 | 18 | #include <linux/syscalls.h> |
ba52de12 | 19 | #include <linux/pagemap.h> |
ac565de3 | 20 | #include <linux/compat.h> |
a1175d6b | 21 | #include <linux/iversion.h> |
1da177e4 | 22 | |
7c0f6ba6 | 23 | #include <linux/uaccess.h> |
1da177e4 LT |
24 | #include <asm/unistd.h> |
25 | ||
3934e36f | 26 | #include "internal.h" |
fa2fcf4f | 27 | #include "mount.h" |
3934e36f | 28 | |
a528d35e DH |
29 | /** |
30 | * generic_fillattr - Fill in the basic attributes from the inode struct | |
0d72b928 JL |
31 | * @idmap: idmap of the mount the inode was found from |
32 | * @request_mask: statx request_mask | |
33 | * @inode: Inode to use as the source | |
34 | * @stat: Where to fill in the attributes | |
a528d35e DH |
35 | * |
36 | * Fill in the basic attributes in the kstat structure from data that's to be | |
37 | * found on the VFS inode structure. This is the default if no getattr inode | |
38 | * operation is supplied. | |
0d56a451 | 39 | * |
b74d24f7 CB |
40 | * If the inode has been found through an idmapped mount the idmap of |
41 | * the vfsmount must be passed through @idmap. This function will then | |
42 | * take care to map the inode according to @idmap before filling in the | |
0d56a451 | 43 | * uid and gid filds. On non-idmapped mounts or if permission checking is to be |
b74d24f7 | 44 | * performed on the raw inode simply passs @nop_mnt_idmap. |
a528d35e | 45 | */ |
0d72b928 JL |
46 | void generic_fillattr(struct mnt_idmap *idmap, u32 request_mask, |
47 | struct inode *inode, struct kstat *stat) | |
1da177e4 | 48 | { |
e67fe633 CB |
49 | vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode); |
50 | vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode); | |
a2bd096f | 51 | |
1da177e4 LT |
52 | stat->dev = inode->i_sb->s_dev; |
53 | stat->ino = inode->i_ino; | |
54 | stat->mode = inode->i_mode; | |
55 | stat->nlink = inode->i_nlink; | |
a2bd096f CB |
56 | stat->uid = vfsuid_into_kuid(vfsuid); |
57 | stat->gid = vfsgid_into_kgid(vfsgid); | |
1da177e4 | 58 | stat->rdev = inode->i_rdev; |
3ddcd056 | 59 | stat->size = i_size_read(inode); |
16a94965 JL |
60 | stat->atime = inode_get_atime(inode); |
61 | stat->mtime = inode_get_mtime(inode); | |
647aa768 | 62 | stat->ctime = inode_get_ctime(inode); |
93407472 | 63 | stat->blksize = i_blocksize(inode); |
3ddcd056 | 64 | stat->blocks = inode->i_blocks; |
0d72b928 JL |
65 | |
66 | if ((request_mask & STATX_CHANGE_COOKIE) && IS_I_VERSION(inode)) { | |
67 | stat->result_mask |= STATX_CHANGE_COOKIE; | |
68 | stat->change_cookie = inode_query_iversion(inode); | |
69 | } | |
70 | ||
a528d35e | 71 | } |
1da177e4 LT |
72 | EXPORT_SYMBOL(generic_fillattr); |
73 | ||
4f911138 AG |
74 | /** |
75 | * generic_fill_statx_attr - Fill in the statx attributes from the inode flags | |
76 | * @inode: Inode to use as the source | |
77 | * @stat: Where to fill in the attribute flags | |
78 | * | |
79 | * Fill in the STATX_ATTR_* flags in the kstat structure for properties of the | |
80 | * inode that are published on i_flags and enforced by the VFS. | |
81 | */ | |
82 | void generic_fill_statx_attr(struct inode *inode, struct kstat *stat) | |
83 | { | |
84 | if (inode->i_flags & S_IMMUTABLE) | |
85 | stat->attributes |= STATX_ATTR_IMMUTABLE; | |
86 | if (inode->i_flags & S_APPEND) | |
87 | stat->attributes |= STATX_ATTR_APPEND; | |
88 | stat->attributes_mask |= KSTAT_ATTR_VFS_FLAGS; | |
89 | } | |
90 | EXPORT_SYMBOL(generic_fill_statx_attr); | |
91 | ||
b7a6ec52 BF |
92 | /** |
93 | * vfs_getattr_nosec - getattr without security checks | |
94 | * @path: file to get attributes from | |
95 | * @stat: structure to return attributes in | |
a528d35e | 96 | * @request_mask: STATX_xxx flags indicating what the caller wants |
f2d077ff | 97 | * @query_flags: Query mode (AT_STATX_SYNC_TYPE) |
b7a6ec52 BF |
98 | * |
99 | * Get attributes without calling security_inode_getattr. | |
100 | * | |
101 | * Currently the only caller other than vfs_getattr is internal to the | |
a528d35e DH |
102 | * filehandle lookup code, which uses only the inode number and returns no |
103 | * attributes to any user. Any other code probably wants vfs_getattr. | |
b7a6ec52 | 104 | */ |
a528d35e DH |
105 | int vfs_getattr_nosec(const struct path *path, struct kstat *stat, |
106 | u32 request_mask, unsigned int query_flags) | |
1da177e4 | 107 | { |
b74d24f7 | 108 | struct mnt_idmap *idmap; |
bb668734 | 109 | struct inode *inode = d_backing_inode(path->dentry); |
1da177e4 | 110 | |
a528d35e DH |
111 | memset(stat, 0, sizeof(*stat)); |
112 | stat->result_mask |= STATX_BASIC_STATS; | |
f2d077ff | 113 | query_flags &= AT_STATX_SYNC_TYPE; |
801e5237 CH |
114 | |
115 | /* allow the fs to override these if it really wants to */ | |
761e28fa MS |
116 | /* SB_NOATIME means filesystem supplies dummy atime value */ |
117 | if (inode->i_sb->s_flags & SB_NOATIME) | |
801e5237 | 118 | stat->result_mask &= ~STATX_ATIME; |
5afa7e8b TT |
119 | |
120 | /* | |
121 | * Note: If you add another clause to set an attribute flag, please | |
122 | * update attributes_mask below. | |
123 | */ | |
801e5237 CH |
124 | if (IS_AUTOMOUNT(inode)) |
125 | stat->attributes |= STATX_ATTR_AUTOMOUNT; | |
126 | ||
712b2698 IW |
127 | if (IS_DAX(inode)) |
128 | stat->attributes |= STATX_ATTR_DAX; | |
129 | ||
5afa7e8b TT |
130 | stat->attributes_mask |= (STATX_ATTR_AUTOMOUNT | |
131 | STATX_ATTR_DAX); | |
132 | ||
b74d24f7 | 133 | idmap = mnt_idmap(path->mnt); |
1da177e4 | 134 | if (inode->i_op->getattr) |
b74d24f7 | 135 | return inode->i_op->getattr(idmap, path, stat, |
8a924db2 SB |
136 | request_mask, |
137 | query_flags | AT_GETATTR_NOSEC); | |
1da177e4 | 138 | |
0d72b928 | 139 | generic_fillattr(idmap, request_mask, inode, stat); |
1da177e4 LT |
140 | return 0; |
141 | } | |
b7a6ec52 BF |
142 | EXPORT_SYMBOL(vfs_getattr_nosec); |
143 | ||
a528d35e DH |
144 | /* |
145 | * vfs_getattr - Get the enhanced basic attributes of a file | |
146 | * @path: The file of interest | |
147 | * @stat: Where to return the statistics | |
148 | * @request_mask: STATX_xxx flags indicating what the caller wants | |
f2d077ff | 149 | * @query_flags: Query mode (AT_STATX_SYNC_TYPE) |
a528d35e DH |
150 | * |
151 | * Ask the filesystem for a file's attributes. The caller must indicate in | |
152 | * request_mask and query_flags to indicate what they want. | |
153 | * | |
154 | * If the file is remote, the filesystem can be forced to update the attributes | |
155 | * from the backing store by passing AT_STATX_FORCE_SYNC in query_flags or can | |
156 | * suppress the update by passing AT_STATX_DONT_SYNC. | |
157 | * | |
158 | * Bits must have been set in request_mask to indicate which attributes the | |
159 | * caller wants retrieving. Any such attribute not requested may be returned | |
160 | * anyway, but the value may be approximate, and, if remote, may not have been | |
161 | * synchronised with the server. | |
162 | * | |
163 | * 0 will be returned on success, and a -ve error code if unsuccessful. | |
164 | */ | |
165 | int vfs_getattr(const struct path *path, struct kstat *stat, | |
166 | u32 request_mask, unsigned int query_flags) | |
b7a6ec52 BF |
167 | { |
168 | int retval; | |
169 | ||
8a924db2 SB |
170 | if (WARN_ON_ONCE(query_flags & AT_GETATTR_NOSEC)) |
171 | return -EPERM; | |
172 | ||
3f7036a0 | 173 | retval = security_inode_getattr(path); |
b7a6ec52 BF |
174 | if (retval) |
175 | return retval; | |
a528d35e | 176 | return vfs_getattr_nosec(path, stat, request_mask, query_flags); |
b7a6ec52 | 177 | } |
1da177e4 LT |
178 | EXPORT_SYMBOL(vfs_getattr); |
179 | ||
a528d35e | 180 | /** |
da9aa5d9 | 181 | * vfs_fstat - Get the basic attributes by file descriptor |
a528d35e DH |
182 | * @fd: The file descriptor referring to the file of interest |
183 | * @stat: The result structure to fill in. | |
a528d35e DH |
184 | * |
185 | * This function is a wrapper around vfs_getattr(). The main difference is | |
186 | * that it uses a file descriptor to determine the file location. | |
187 | * | |
188 | * 0 will be returned on success, and a -ve error code if unsuccessful. | |
189 | */ | |
da9aa5d9 | 190 | int vfs_fstat(int fd, struct kstat *stat) |
1da177e4 | 191 | { |
8c7493aa | 192 | struct fd f; |
da9aa5d9 | 193 | int error; |
8c7493aa EB |
194 | |
195 | f = fdget_raw(fd); | |
da9aa5d9 CH |
196 | if (!f.file) |
197 | return -EBADF; | |
198 | error = vfs_getattr(&f.file->f_path, stat, STATX_BASIC_STATS, 0); | |
199 | fdput(f); | |
1da177e4 LT |
200 | return error; |
201 | } | |
1da177e4 | 202 | |
1b6fe6e0 SR |
203 | int getname_statx_lookup_flags(int flags) |
204 | { | |
205 | int lookup_flags = 0; | |
206 | ||
207 | if (!(flags & AT_SYMLINK_NOFOLLOW)) | |
208 | lookup_flags |= LOOKUP_FOLLOW; | |
209 | if (!(flags & AT_NO_AUTOMOUNT)) | |
210 | lookup_flags |= LOOKUP_AUTOMOUNT; | |
211 | if (flags & AT_EMPTY_PATH) | |
212 | lookup_flags |= LOOKUP_EMPTY; | |
213 | ||
214 | return lookup_flags; | |
215 | } | |
216 | ||
a528d35e DH |
217 | /** |
218 | * vfs_statx - Get basic and extra attributes by filename | |
219 | * @dfd: A file descriptor representing the base dir for a relative filename | |
220 | * @filename: The name of the file of interest | |
221 | * @flags: Flags to control the query | |
222 | * @stat: The result structure to fill in. | |
223 | * @request_mask: STATX_xxx flags indicating what the caller wants | |
224 | * | |
225 | * This function is a wrapper around vfs_getattr(). The main difference is | |
226 | * that it uses a filename and base directory to determine the file location. | |
227 | * Additionally, the use of AT_SYMLINK_NOFOLLOW in flags will prevent a symlink | |
228 | * at the given name from being referenced. | |
229 | * | |
a528d35e DH |
230 | * 0 will be returned on success, and a -ve error code if unsuccessful. |
231 | */ | |
1b6fe6e0 | 232 | static int vfs_statx(int dfd, struct filename *filename, int flags, |
a528d35e | 233 | struct kstat *stat, u32 request_mask) |
0112fc22 | 234 | { |
2eae7a18 | 235 | struct path path; |
1b6fe6e0 | 236 | unsigned int lookup_flags = getname_statx_lookup_flags(flags); |
b3f05150 | 237 | int error; |
0112fc22 | 238 | |
b3f05150 | 239 | if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT | AT_EMPTY_PATH | |
f2d077ff | 240 | AT_STATX_SYNC_TYPE)) |
a528d35e | 241 | return -EINVAL; |
b3f05150 | 242 | |
836fb7e7 | 243 | retry: |
1b6fe6e0 | 244 | error = filename_lookup(dfd, filename, lookup_flags, &path, NULL); |
2eae7a18 CH |
245 | if (error) |
246 | goto out; | |
247 | ||
a528d35e | 248 | error = vfs_getattr(&path, stat, request_mask, flags); |
2d985f8c | 249 | |
fa2fcf4f MS |
250 | stat->mnt_id = real_mount(path.mnt)->mnt_id; |
251 | stat->result_mask |= STATX_MNT_ID; | |
2d985f8c | 252 | |
80340fe3 MS |
253 | if (path.mnt->mnt_root == path.dentry) |
254 | stat->attributes |= STATX_ATTR_MOUNT_ROOT; | |
255 | stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT; | |
2d985f8c EB |
256 | |
257 | /* Handle STATX_DIOALIGN for block devices. */ | |
258 | if (request_mask & STATX_DIOALIGN) { | |
259 | struct inode *inode = d_backing_inode(path.dentry); | |
260 | ||
261 | if (S_ISBLK(inode->i_mode)) | |
262 | bdev_statx_dioalign(inode, stat); | |
263 | } | |
264 | ||
2eae7a18 | 265 | path_put(&path); |
836fb7e7 JL |
266 | if (retry_estale(error, lookup_flags)) { |
267 | lookup_flags |= LOOKUP_REVAL; | |
268 | goto retry; | |
269 | } | |
0112fc22 OD |
270 | out: |
271 | return error; | |
272 | } | |
2eae7a18 | 273 | |
09f1bde4 CH |
274 | int vfs_fstatat(int dfd, const char __user *filename, |
275 | struct kstat *stat, int flags) | |
276 | { | |
1b6fe6e0 SR |
277 | int ret; |
278 | int statx_flags = flags | AT_NO_AUTOMOUNT; | |
279 | struct filename *name; | |
280 | ||
9013c51c LT |
281 | /* |
282 | * Work around glibc turning fstat() into fstatat(AT_EMPTY_PATH) | |
283 | * | |
284 | * If AT_EMPTY_PATH is set, we expect the common case to be that | |
285 | * empty path, and avoid doing all the extra pathname work. | |
286 | */ | |
287 | if (dfd >= 0 && flags == AT_EMPTY_PATH) { | |
288 | char c; | |
289 | ||
290 | ret = get_user(c, filename); | |
291 | if (unlikely(ret)) | |
292 | return ret; | |
293 | ||
294 | if (likely(!c)) | |
295 | return vfs_fstat(dfd, stat); | |
296 | } | |
297 | ||
1b6fe6e0 SR |
298 | name = getname_flags(filename, getname_statx_lookup_flags(statx_flags), NULL); |
299 | ret = vfs_statx(dfd, name, statx_flags, stat, STATX_BASIC_STATS); | |
300 | putname(name); | |
301 | ||
302 | return ret; | |
09f1bde4 | 303 | } |
0112fc22 | 304 | |
1da177e4 LT |
305 | #ifdef __ARCH_WANT_OLD_STAT |
306 | ||
307 | /* | |
308 | * For backward compatibility? Maybe this should be moved | |
309 | * into arch/i386 instead? | |
310 | */ | |
311 | static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf) | |
312 | { | |
313 | static int warncount = 5; | |
314 | struct __old_kernel_stat tmp; | |
a528d35e | 315 | |
1da177e4 LT |
316 | if (warncount > 0) { |
317 | warncount--; | |
318 | printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n", | |
319 | current->comm); | |
320 | } else if (warncount < 0) { | |
321 | /* it's laughable, but... */ | |
322 | warncount = 0; | |
323 | } | |
324 | ||
325 | memset(&tmp, 0, sizeof(struct __old_kernel_stat)); | |
326 | tmp.st_dev = old_encode_dev(stat->dev); | |
327 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
328 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
329 | return -EOVERFLOW; | |
1da177e4 LT |
330 | tmp.st_mode = stat->mode; |
331 | tmp.st_nlink = stat->nlink; | |
332 | if (tmp.st_nlink != stat->nlink) | |
333 | return -EOVERFLOW; | |
a7c1938e EB |
334 | SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); |
335 | SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); | |
1da177e4 LT |
336 | tmp.st_rdev = old_encode_dev(stat->rdev); |
337 | #if BITS_PER_LONG == 32 | |
338 | if (stat->size > MAX_NON_LFS) | |
339 | return -EOVERFLOW; | |
a528d35e | 340 | #endif |
1da177e4 LT |
341 | tmp.st_size = stat->size; |
342 | tmp.st_atime = stat->atime.tv_sec; | |
343 | tmp.st_mtime = stat->mtime.tv_sec; | |
344 | tmp.st_ctime = stat->ctime.tv_sec; | |
345 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
346 | } | |
347 | ||
c7887325 DH |
348 | SYSCALL_DEFINE2(stat, const char __user *, filename, |
349 | struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
350 | { |
351 | struct kstat stat; | |
2eae7a18 | 352 | int error; |
1da177e4 | 353 | |
2eae7a18 CH |
354 | error = vfs_stat(filename, &stat); |
355 | if (error) | |
356 | return error; | |
1da177e4 | 357 | |
2eae7a18 | 358 | return cp_old_stat(&stat, statbuf); |
1da177e4 | 359 | } |
257ac264 | 360 | |
c7887325 DH |
361 | SYSCALL_DEFINE2(lstat, const char __user *, filename, |
362 | struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
363 | { |
364 | struct kstat stat; | |
2eae7a18 | 365 | int error; |
1da177e4 | 366 | |
2eae7a18 CH |
367 | error = vfs_lstat(filename, &stat); |
368 | if (error) | |
369 | return error; | |
1da177e4 | 370 | |
2eae7a18 | 371 | return cp_old_stat(&stat, statbuf); |
1da177e4 | 372 | } |
257ac264 HC |
373 | |
374 | SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
375 | { |
376 | struct kstat stat; | |
377 | int error = vfs_fstat(fd, &stat); | |
378 | ||
379 | if (!error) | |
380 | error = cp_old_stat(&stat, statbuf); | |
381 | ||
382 | return error; | |
383 | } | |
384 | ||
385 | #endif /* __ARCH_WANT_OLD_STAT */ | |
386 | ||
82b355d1 AB |
387 | #ifdef __ARCH_WANT_NEW_STAT |
388 | ||
8529f613 LT |
389 | #ifndef INIT_STRUCT_STAT_PADDING |
390 | # define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st)) | |
391 | #endif | |
392 | ||
1da177e4 LT |
393 | static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) |
394 | { | |
395 | struct stat tmp; | |
396 | ||
932aba1e MP |
397 | if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev)) |
398 | return -EOVERFLOW; | |
399 | if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev)) | |
1da177e4 | 400 | return -EOVERFLOW; |
a52dd971 LT |
401 | #if BITS_PER_LONG == 32 |
402 | if (stat->size > MAX_NON_LFS) | |
1da177e4 LT |
403 | return -EOVERFLOW; |
404 | #endif | |
405 | ||
8529f613 | 406 | INIT_STRUCT_STAT_PADDING(tmp); |
932aba1e | 407 | tmp.st_dev = new_encode_dev(stat->dev); |
1da177e4 | 408 | tmp.st_ino = stat->ino; |
afefdbb2 DH |
409 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
410 | return -EOVERFLOW; | |
1da177e4 LT |
411 | tmp.st_mode = stat->mode; |
412 | tmp.st_nlink = stat->nlink; | |
413 | if (tmp.st_nlink != stat->nlink) | |
414 | return -EOVERFLOW; | |
a7c1938e EB |
415 | SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); |
416 | SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); | |
932aba1e | 417 | tmp.st_rdev = new_encode_dev(stat->rdev); |
1da177e4 LT |
418 | tmp.st_size = stat->size; |
419 | tmp.st_atime = stat->atime.tv_sec; | |
420 | tmp.st_mtime = stat->mtime.tv_sec; | |
421 | tmp.st_ctime = stat->ctime.tv_sec; | |
422 | #ifdef STAT_HAVE_NSEC | |
423 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
424 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
425 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
426 | #endif | |
427 | tmp.st_blocks = stat->blocks; | |
428 | tmp.st_blksize = stat->blksize; | |
429 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
430 | } | |
431 | ||
c7887325 DH |
432 | SYSCALL_DEFINE2(newstat, const char __user *, filename, |
433 | struct stat __user *, statbuf) | |
5590ff0d UD |
434 | { |
435 | struct kstat stat; | |
2eae7a18 | 436 | int error = vfs_stat(filename, &stat); |
5590ff0d | 437 | |
2eae7a18 CH |
438 | if (error) |
439 | return error; | |
440 | return cp_new_stat(&stat, statbuf); | |
5590ff0d UD |
441 | } |
442 | ||
c7887325 DH |
443 | SYSCALL_DEFINE2(newlstat, const char __user *, filename, |
444 | struct stat __user *, statbuf) | |
1da177e4 LT |
445 | { |
446 | struct kstat stat; | |
2eae7a18 | 447 | int error; |
1da177e4 | 448 | |
2eae7a18 CH |
449 | error = vfs_lstat(filename, &stat); |
450 | if (error) | |
451 | return error; | |
1da177e4 | 452 | |
2eae7a18 | 453 | return cp_new_stat(&stat, statbuf); |
1da177e4 | 454 | } |
5590ff0d | 455 | |
2833c28a | 456 | #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT) |
c7887325 | 457 | SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename, |
6559eed8 | 458 | struct stat __user *, statbuf, int, flag) |
1da177e4 LT |
459 | { |
460 | struct kstat stat; | |
0112fc22 | 461 | int error; |
1da177e4 | 462 | |
0112fc22 OD |
463 | error = vfs_fstatat(dfd, filename, &stat, flag); |
464 | if (error) | |
465 | return error; | |
466 | return cp_new_stat(&stat, statbuf); | |
1da177e4 | 467 | } |
cff2b760 | 468 | #endif |
5590ff0d | 469 | |
257ac264 | 470 | SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf) |
1da177e4 LT |
471 | { |
472 | struct kstat stat; | |
473 | int error = vfs_fstat(fd, &stat); | |
474 | ||
475 | if (!error) | |
476 | error = cp_new_stat(&stat, statbuf); | |
477 | ||
478 | return error; | |
479 | } | |
82b355d1 | 480 | #endif |
1da177e4 | 481 | |
2dae0248 DB |
482 | static int do_readlinkat(int dfd, const char __user *pathname, |
483 | char __user *buf, int bufsiz) | |
1da177e4 | 484 | { |
2d8f3038 | 485 | struct path path; |
1da177e4 | 486 | int error; |
1fa1e7f6 | 487 | int empty = 0; |
7955119e | 488 | unsigned int lookup_flags = LOOKUP_EMPTY; |
1da177e4 LT |
489 | |
490 | if (bufsiz <= 0) | |
491 | return -EINVAL; | |
492 | ||
7955119e JL |
493 | retry: |
494 | error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty); | |
1da177e4 | 495 | if (!error) { |
bb668734 | 496 | struct inode *inode = d_backing_inode(path.dentry); |
1da177e4 | 497 | |
1fa1e7f6 | 498 | error = empty ? -ENOENT : -EINVAL; |
fd4a0edf MS |
499 | /* |
500 | * AFS mountpoints allow readlink(2) but are not symlinks | |
501 | */ | |
502 | if (d_is_symlink(path.dentry) || inode->i_op->readlink) { | |
2d8f3038 | 503 | error = security_inode_readlink(path.dentry); |
1da177e4 | 504 | if (!error) { |
68ac1234 | 505 | touch_atime(&path); |
fd4a0edf | 506 | error = vfs_readlink(path.dentry, buf, bufsiz); |
1da177e4 LT |
507 | } |
508 | } | |
2d8f3038 | 509 | path_put(&path); |
7955119e JL |
510 | if (retry_estale(error, lookup_flags)) { |
511 | lookup_flags |= LOOKUP_REVAL; | |
512 | goto retry; | |
513 | } | |
1da177e4 LT |
514 | } |
515 | return error; | |
516 | } | |
517 | ||
2dae0248 DB |
518 | SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname, |
519 | char __user *, buf, int, bufsiz) | |
520 | { | |
521 | return do_readlinkat(dfd, pathname, buf, bufsiz); | |
522 | } | |
523 | ||
002c8976 HC |
524 | SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf, |
525 | int, bufsiz) | |
5590ff0d | 526 | { |
2dae0248 | 527 | return do_readlinkat(AT_FDCWD, path, buf, bufsiz); |
5590ff0d UD |
528 | } |
529 | ||
1da177e4 LT |
530 | |
531 | /* ---------- LFS-64 ----------- */ | |
0753f70f | 532 | #if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64) |
1da177e4 | 533 | |
8529f613 LT |
534 | #ifndef INIT_STRUCT_STAT64_PADDING |
535 | # define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st)) | |
536 | #endif | |
537 | ||
1da177e4 LT |
538 | static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf) |
539 | { | |
540 | struct stat64 tmp; | |
541 | ||
8529f613 | 542 | INIT_STRUCT_STAT64_PADDING(tmp); |
1da177e4 LT |
543 | #ifdef CONFIG_MIPS |
544 | /* mips has weird padding, so we don't get 64 bits there */ | |
1da177e4 LT |
545 | tmp.st_dev = new_encode_dev(stat->dev); |
546 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
547 | #else | |
548 | tmp.st_dev = huge_encode_dev(stat->dev); | |
549 | tmp.st_rdev = huge_encode_dev(stat->rdev); | |
550 | #endif | |
551 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
552 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
553 | return -EOVERFLOW; | |
1da177e4 LT |
554 | #ifdef STAT64_HAS_BROKEN_ST_INO |
555 | tmp.__st_ino = stat->ino; | |
556 | #endif | |
557 | tmp.st_mode = stat->mode; | |
558 | tmp.st_nlink = stat->nlink; | |
a7c1938e EB |
559 | tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid); |
560 | tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid); | |
1da177e4 LT |
561 | tmp.st_atime = stat->atime.tv_sec; |
562 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
563 | tmp.st_mtime = stat->mtime.tv_sec; | |
564 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
565 | tmp.st_ctime = stat->ctime.tv_sec; | |
566 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
567 | tmp.st_size = stat->size; | |
568 | tmp.st_blocks = stat->blocks; | |
569 | tmp.st_blksize = stat->blksize; | |
570 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
571 | } | |
572 | ||
c7887325 DH |
573 | SYSCALL_DEFINE2(stat64, const char __user *, filename, |
574 | struct stat64 __user *, statbuf) | |
1da177e4 LT |
575 | { |
576 | struct kstat stat; | |
577 | int error = vfs_stat(filename, &stat); | |
578 | ||
579 | if (!error) | |
580 | error = cp_new_stat64(&stat, statbuf); | |
581 | ||
582 | return error; | |
583 | } | |
257ac264 | 584 | |
c7887325 DH |
585 | SYSCALL_DEFINE2(lstat64, const char __user *, filename, |
586 | struct stat64 __user *, statbuf) | |
1da177e4 LT |
587 | { |
588 | struct kstat stat; | |
589 | int error = vfs_lstat(filename, &stat); | |
590 | ||
591 | if (!error) | |
592 | error = cp_new_stat64(&stat, statbuf); | |
593 | ||
594 | return error; | |
595 | } | |
257ac264 HC |
596 | |
597 | SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf) | |
1da177e4 LT |
598 | { |
599 | struct kstat stat; | |
600 | int error = vfs_fstat(fd, &stat); | |
601 | ||
602 | if (!error) | |
603 | error = cp_new_stat64(&stat, statbuf); | |
604 | ||
605 | return error; | |
606 | } | |
607 | ||
c7887325 | 608 | SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename, |
6559eed8 | 609 | struct stat64 __user *, statbuf, int, flag) |
cff2b760 UD |
610 | { |
611 | struct kstat stat; | |
0112fc22 | 612 | int error; |
cff2b760 | 613 | |
0112fc22 OD |
614 | error = vfs_fstatat(dfd, filename, &stat, flag); |
615 | if (error) | |
616 | return error; | |
617 | return cp_new_stat64(&stat, statbuf); | |
cff2b760 | 618 | } |
0753f70f | 619 | #endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */ |
1da177e4 | 620 | |
6f88cc17 | 621 | static noinline_for_stack int |
64bd7204 | 622 | cp_statx(const struct kstat *stat, struct statx __user *buffer) |
a528d35e | 623 | { |
64bd7204 EB |
624 | struct statx tmp; |
625 | ||
626 | memset(&tmp, 0, sizeof(tmp)); | |
627 | ||
a1175d6b JL |
628 | /* STATX_CHANGE_COOKIE is kernel-only for now */ |
629 | tmp.stx_mask = stat->result_mask & ~STATX_CHANGE_COOKIE; | |
64bd7204 | 630 | tmp.stx_blksize = stat->blksize; |
a1175d6b JL |
631 | /* STATX_ATTR_CHANGE_MONOTONIC is kernel-only for now */ |
632 | tmp.stx_attributes = stat->attributes & ~STATX_ATTR_CHANGE_MONOTONIC; | |
64bd7204 EB |
633 | tmp.stx_nlink = stat->nlink; |
634 | tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid); | |
635 | tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid); | |
636 | tmp.stx_mode = stat->mode; | |
637 | tmp.stx_ino = stat->ino; | |
638 | tmp.stx_size = stat->size; | |
639 | tmp.stx_blocks = stat->blocks; | |
3209f68b | 640 | tmp.stx_attributes_mask = stat->attributes_mask; |
64bd7204 EB |
641 | tmp.stx_atime.tv_sec = stat->atime.tv_sec; |
642 | tmp.stx_atime.tv_nsec = stat->atime.tv_nsec; | |
643 | tmp.stx_btime.tv_sec = stat->btime.tv_sec; | |
644 | tmp.stx_btime.tv_nsec = stat->btime.tv_nsec; | |
645 | tmp.stx_ctime.tv_sec = stat->ctime.tv_sec; | |
646 | tmp.stx_ctime.tv_nsec = stat->ctime.tv_nsec; | |
647 | tmp.stx_mtime.tv_sec = stat->mtime.tv_sec; | |
648 | tmp.stx_mtime.tv_nsec = stat->mtime.tv_nsec; | |
649 | tmp.stx_rdev_major = MAJOR(stat->rdev); | |
650 | tmp.stx_rdev_minor = MINOR(stat->rdev); | |
651 | tmp.stx_dev_major = MAJOR(stat->dev); | |
652 | tmp.stx_dev_minor = MINOR(stat->dev); | |
fa2fcf4f | 653 | tmp.stx_mnt_id = stat->mnt_id; |
825cf206 EB |
654 | tmp.stx_dio_mem_align = stat->dio_mem_align; |
655 | tmp.stx_dio_offset_align = stat->dio_offset_align; | |
64bd7204 EB |
656 | |
657 | return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0; | |
a528d35e DH |
658 | } |
659 | ||
1b6fe6e0 | 660 | int do_statx(int dfd, struct filename *filename, unsigned int flags, |
0018784f BM |
661 | unsigned int mask, struct statx __user *buffer) |
662 | { | |
663 | struct kstat stat; | |
664 | int error; | |
665 | ||
666 | if (mask & STATX__RESERVED) | |
667 | return -EINVAL; | |
668 | if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE) | |
669 | return -EINVAL; | |
670 | ||
a1175d6b JL |
671 | /* STATX_CHANGE_COOKIE is kernel-only for now. Ignore requests |
672 | * from userland. | |
673 | */ | |
674 | mask &= ~STATX_CHANGE_COOKIE; | |
675 | ||
0018784f BM |
676 | error = vfs_statx(dfd, filename, flags, &stat, mask); |
677 | if (error) | |
678 | return error; | |
679 | ||
680 | return cp_statx(&stat, buffer); | |
681 | } | |
682 | ||
a528d35e DH |
683 | /** |
684 | * sys_statx - System call to get enhanced stats | |
685 | * @dfd: Base directory to pathwalk from *or* fd to stat. | |
1e2f82d1 | 686 | * @filename: File to stat or "" with AT_EMPTY_PATH |
a528d35e DH |
687 | * @flags: AT_* flags to control pathwalk. |
688 | * @mask: Parts of statx struct actually required. | |
689 | * @buffer: Result buffer. | |
690 | * | |
1e2f82d1 DH |
691 | * Note that fstat() can be emulated by setting dfd to the fd of interest, |
692 | * supplying "" as the filename and setting AT_EMPTY_PATH in the flags. | |
a528d35e DH |
693 | */ |
694 | SYSCALL_DEFINE5(statx, | |
695 | int, dfd, const char __user *, filename, unsigned, flags, | |
696 | unsigned int, mask, | |
697 | struct statx __user *, buffer) | |
698 | { | |
1b6fe6e0 SR |
699 | int ret; |
700 | struct filename *name; | |
701 | ||
702 | name = getname_flags(filename, getname_statx_lookup_flags(flags), NULL); | |
703 | ret = do_statx(dfd, name, flags, mask, buffer); | |
704 | putname(name); | |
705 | ||
706 | return ret; | |
a528d35e DH |
707 | } |
708 | ||
f18ed30d | 709 | #if defined(CONFIG_COMPAT) && defined(__ARCH_WANT_COMPAT_STAT) |
ac565de3 AV |
710 | static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf) |
711 | { | |
712 | struct compat_stat tmp; | |
713 | ||
932aba1e MP |
714 | if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev)) |
715 | return -EOVERFLOW; | |
716 | if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev)) | |
ac565de3 AV |
717 | return -EOVERFLOW; |
718 | ||
719 | memset(&tmp, 0, sizeof(tmp)); | |
932aba1e | 720 | tmp.st_dev = new_encode_dev(stat->dev); |
ac565de3 AV |
721 | tmp.st_ino = stat->ino; |
722 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) | |
723 | return -EOVERFLOW; | |
724 | tmp.st_mode = stat->mode; | |
725 | tmp.st_nlink = stat->nlink; | |
726 | if (tmp.st_nlink != stat->nlink) | |
727 | return -EOVERFLOW; | |
728 | SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); | |
729 | SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); | |
932aba1e | 730 | tmp.st_rdev = new_encode_dev(stat->rdev); |
ac565de3 AV |
731 | if ((u64) stat->size > MAX_NON_LFS) |
732 | return -EOVERFLOW; | |
733 | tmp.st_size = stat->size; | |
734 | tmp.st_atime = stat->atime.tv_sec; | |
735 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
736 | tmp.st_mtime = stat->mtime.tv_sec; | |
737 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
738 | tmp.st_ctime = stat->ctime.tv_sec; | |
739 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
740 | tmp.st_blocks = stat->blocks; | |
741 | tmp.st_blksize = stat->blksize; | |
742 | return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0; | |
743 | } | |
744 | ||
745 | COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename, | |
746 | struct compat_stat __user *, statbuf) | |
747 | { | |
748 | struct kstat stat; | |
749 | int error; | |
750 | ||
751 | error = vfs_stat(filename, &stat); | |
752 | if (error) | |
753 | return error; | |
754 | return cp_compat_stat(&stat, statbuf); | |
755 | } | |
756 | ||
757 | COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename, | |
758 | struct compat_stat __user *, statbuf) | |
759 | { | |
760 | struct kstat stat; | |
761 | int error; | |
762 | ||
763 | error = vfs_lstat(filename, &stat); | |
764 | if (error) | |
765 | return error; | |
766 | return cp_compat_stat(&stat, statbuf); | |
767 | } | |
768 | ||
769 | #ifndef __ARCH_WANT_STAT64 | |
770 | COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd, | |
771 | const char __user *, filename, | |
772 | struct compat_stat __user *, statbuf, int, flag) | |
773 | { | |
774 | struct kstat stat; | |
775 | int error; | |
776 | ||
777 | error = vfs_fstatat(dfd, filename, &stat, flag); | |
778 | if (error) | |
779 | return error; | |
780 | return cp_compat_stat(&stat, statbuf); | |
781 | } | |
782 | #endif | |
783 | ||
784 | COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd, | |
785 | struct compat_stat __user *, statbuf) | |
786 | { | |
787 | struct kstat stat; | |
788 | int error = vfs_fstat(fd, &stat); | |
789 | ||
790 | if (!error) | |
791 | error = cp_compat_stat(&stat, statbuf); | |
792 | return error; | |
793 | } | |
794 | #endif | |
795 | ||
b462707e DM |
796 | /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */ |
797 | void __inode_add_bytes(struct inode *inode, loff_t bytes) | |
1da177e4 | 798 | { |
1da177e4 LT |
799 | inode->i_blocks += bytes >> 9; |
800 | bytes &= 511; | |
801 | inode->i_bytes += bytes; | |
802 | if (inode->i_bytes >= 512) { | |
803 | inode->i_blocks++; | |
804 | inode->i_bytes -= 512; | |
805 | } | |
b462707e | 806 | } |
eb315d2a | 807 | EXPORT_SYMBOL(__inode_add_bytes); |
b462707e DM |
808 | |
809 | void inode_add_bytes(struct inode *inode, loff_t bytes) | |
810 | { | |
811 | spin_lock(&inode->i_lock); | |
812 | __inode_add_bytes(inode, bytes); | |
1da177e4 LT |
813 | spin_unlock(&inode->i_lock); |
814 | } | |
815 | ||
816 | EXPORT_SYMBOL(inode_add_bytes); | |
817 | ||
1c8924eb | 818 | void __inode_sub_bytes(struct inode *inode, loff_t bytes) |
1da177e4 | 819 | { |
1da177e4 LT |
820 | inode->i_blocks -= bytes >> 9; |
821 | bytes &= 511; | |
822 | if (inode->i_bytes < bytes) { | |
823 | inode->i_blocks--; | |
824 | inode->i_bytes += 512; | |
825 | } | |
826 | inode->i_bytes -= bytes; | |
1c8924eb JK |
827 | } |
828 | ||
829 | EXPORT_SYMBOL(__inode_sub_bytes); | |
830 | ||
831 | void inode_sub_bytes(struct inode *inode, loff_t bytes) | |
832 | { | |
833 | spin_lock(&inode->i_lock); | |
834 | __inode_sub_bytes(inode, bytes); | |
1da177e4 LT |
835 | spin_unlock(&inode->i_lock); |
836 | } | |
837 | ||
838 | EXPORT_SYMBOL(inode_sub_bytes); | |
839 | ||
840 | loff_t inode_get_bytes(struct inode *inode) | |
841 | { | |
842 | loff_t ret; | |
843 | ||
844 | spin_lock(&inode->i_lock); | |
f4a8116a | 845 | ret = __inode_get_bytes(inode); |
1da177e4 LT |
846 | spin_unlock(&inode->i_lock); |
847 | return ret; | |
848 | } | |
849 | ||
850 | EXPORT_SYMBOL(inode_get_bytes); | |
851 | ||
852 | void inode_set_bytes(struct inode *inode, loff_t bytes) | |
853 | { | |
854 | /* Caller is here responsible for sufficient locking | |
855 | * (ie. inode->i_lock) */ | |
856 | inode->i_blocks = bytes >> 9; | |
857 | inode->i_bytes = bytes & 511; | |
858 | } | |
859 | ||
860 | EXPORT_SYMBOL(inode_set_bytes); |