]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/open.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
7 | #include <linux/string.h> | |
8 | #include <linux/mm.h> | |
1da177e4 | 9 | #include <linux/file.h> |
9f3acc31 | 10 | #include <linux/fdtable.h> |
0eeca283 | 11 | #include <linux/fsnotify.h> |
1da177e4 | 12 | #include <linux/module.h> |
1da177e4 LT |
13 | #include <linux/tty.h> |
14 | #include <linux/namei.h> | |
15 | #include <linux/backing-dev.h> | |
16f7e0fe | 16 | #include <linux/capability.h> |
086f7316 | 17 | #include <linux/securebits.h> |
1da177e4 LT |
18 | #include <linux/security.h> |
19 | #include <linux/mount.h> | |
5590ff0d | 20 | #include <linux/fcntl.h> |
5a0e3ad6 | 21 | #include <linux/slab.h> |
1da177e4 LT |
22 | #include <asm/uaccess.h> |
23 | #include <linux/fs.h> | |
ef3daeda | 24 | #include <linux/personality.h> |
1da177e4 LT |
25 | #include <linux/pagemap.h> |
26 | #include <linux/syscalls.h> | |
ab2af1f5 | 27 | #include <linux/rcupdate.h> |
73241ccc | 28 | #include <linux/audit.h> |
97ac7350 | 29 | #include <linux/falloc.h> |
5ad4e53b | 30 | #include <linux/fs_struct.h> |
b65a9cfc | 31 | #include <linux/ima.h> |
2dfc1cae | 32 | #include <linux/dnotify.h> |
1da177e4 | 33 | |
e81e3f4d EP |
34 | #include "internal.h" |
35 | ||
4a30131e N |
36 | int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, |
37 | struct file *filp) | |
1da177e4 | 38 | { |
939a9421 | 39 | int ret; |
1da177e4 LT |
40 | struct iattr newattrs; |
41 | ||
42 | /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */ | |
43 | if (length < 0) | |
44 | return -EINVAL; | |
45 | ||
46 | newattrs.ia_size = length; | |
4a30131e | 47 | newattrs.ia_valid = ATTR_SIZE | time_attrs; |
cc4e69de MS |
48 | if (filp) { |
49 | newattrs.ia_file = filp; | |
50 | newattrs.ia_valid |= ATTR_FILE; | |
51 | } | |
1da177e4 | 52 | |
7b82dc0e | 53 | /* Remove suid/sgid on truncate too */ |
939a9421 AW |
54 | ret = should_remove_suid(dentry); |
55 | if (ret) | |
56 | newattrs.ia_valid |= ret | ATTR_FORCE; | |
7b82dc0e | 57 | |
1b1dcc1b | 58 | mutex_lock(&dentry->d_inode->i_mutex); |
939a9421 | 59 | ret = notify_change(dentry, &newattrs); |
1b1dcc1b | 60 | mutex_unlock(&dentry->d_inode->i_mutex); |
939a9421 | 61 | return ret; |
1da177e4 LT |
62 | } |
63 | ||
a02de960 | 64 | long vfs_truncate(struct path *path, loff_t length) |
1da177e4 | 65 | { |
2d8f3038 | 66 | struct inode *inode; |
a02de960 | 67 | long error; |
1da177e4 | 68 | |
a02de960 | 69 | inode = path->dentry->d_inode; |
1da177e4 LT |
70 | |
71 | /* For directories it's -EISDIR, for other non-regulars - -EINVAL */ | |
1da177e4 | 72 | if (S_ISDIR(inode->i_mode)) |
a02de960 | 73 | return -EISDIR; |
1da177e4 | 74 | if (!S_ISREG(inode->i_mode)) |
a02de960 | 75 | return -EINVAL; |
1da177e4 | 76 | |
a02de960 | 77 | error = mnt_want_write(path->mnt); |
1da177e4 | 78 | if (error) |
a02de960 | 79 | goto out; |
1da177e4 | 80 | |
256984a8 | 81 | error = inode_permission(inode, MAY_WRITE); |
9ac9b847 DH |
82 | if (error) |
83 | goto mnt_drop_write_and_out; | |
1da177e4 LT |
84 | |
85 | error = -EPERM; | |
c82e42da | 86 | if (IS_APPEND(inode)) |
9ac9b847 | 87 | goto mnt_drop_write_and_out; |
1da177e4 | 88 | |
9700382c | 89 | error = get_write_access(inode); |
1da177e4 | 90 | if (error) |
9ac9b847 | 91 | goto mnt_drop_write_and_out; |
1da177e4 | 92 | |
9700382c | 93 | /* |
94 | * Make sure that there are no leases. get_write_access() protects | |
95 | * against the truncate racing with a lease-granting setlease(). | |
96 | */ | |
8737c930 | 97 | error = break_lease(inode, O_WRONLY); |
1da177e4 | 98 | if (error) |
9700382c | 99 | goto put_write_and_out; |
1da177e4 LT |
100 | |
101 | error = locks_verify_truncate(inode, NULL, length); | |
be6d3e56 | 102 | if (!error) |
a02de960 | 103 | error = security_path_truncate(path); |
907f4554 | 104 | if (!error) |
a02de960 | 105 | error = do_truncate(path->dentry, length, 0, NULL); |
1da177e4 | 106 | |
9700382c | 107 | put_write_and_out: |
108 | put_write_access(inode); | |
9ac9b847 | 109 | mnt_drop_write_and_out: |
a02de960 | 110 | mnt_drop_write(path->mnt); |
1da177e4 LT |
111 | out: |
112 | return error; | |
113 | } | |
a02de960 DH |
114 | EXPORT_SYMBOL_GPL(vfs_truncate); |
115 | ||
116 | static long do_sys_truncate(const char __user *pathname, loff_t length) | |
117 | { | |
48f7530d | 118 | unsigned int lookup_flags = LOOKUP_FOLLOW; |
a02de960 DH |
119 | struct path path; |
120 | int error; | |
121 | ||
122 | if (length < 0) /* sorry, but loff_t says... */ | |
123 | return -EINVAL; | |
124 | ||
48f7530d JL |
125 | retry: |
126 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); | |
a02de960 DH |
127 | if (!error) { |
128 | error = vfs_truncate(&path, length); | |
129 | path_put(&path); | |
130 | } | |
48f7530d JL |
131 | if (retry_estale(error, lookup_flags)) { |
132 | lookup_flags |= LOOKUP_REVAL; | |
133 | goto retry; | |
134 | } | |
a02de960 DH |
135 | return error; |
136 | } | |
1da177e4 | 137 | |
4fd8da8d | 138 | SYSCALL_DEFINE2(truncate, const char __user *, path, long, length) |
1da177e4 | 139 | { |
4fd8da8d | 140 | return do_sys_truncate(path, length); |
1da177e4 LT |
141 | } |
142 | ||
b01ec0ef | 143 | static long do_sys_ftruncate(unsigned int fd, loff_t length, int small) |
1da177e4 | 144 | { |
bf2965d5 | 145 | struct inode *inode; |
1da177e4 | 146 | struct dentry *dentry; |
2903ff01 | 147 | struct fd f; |
1da177e4 LT |
148 | int error; |
149 | ||
150 | error = -EINVAL; | |
151 | if (length < 0) | |
152 | goto out; | |
153 | error = -EBADF; | |
2903ff01 AV |
154 | f = fdget(fd); |
155 | if (!f.file) | |
1da177e4 LT |
156 | goto out; |
157 | ||
158 | /* explicitly opened as large or we are on 64-bit box */ | |
2903ff01 | 159 | if (f.file->f_flags & O_LARGEFILE) |
1da177e4 LT |
160 | small = 0; |
161 | ||
2903ff01 | 162 | dentry = f.file->f_path.dentry; |
1da177e4 LT |
163 | inode = dentry->d_inode; |
164 | error = -EINVAL; | |
2903ff01 | 165 | if (!S_ISREG(inode->i_mode) || !(f.file->f_mode & FMODE_WRITE)) |
1da177e4 LT |
166 | goto out_putf; |
167 | ||
168 | error = -EINVAL; | |
169 | /* Cannot ftruncate over 2^31 bytes without large file support */ | |
170 | if (small && length > MAX_NON_LFS) | |
171 | goto out_putf; | |
172 | ||
173 | error = -EPERM; | |
174 | if (IS_APPEND(inode)) | |
175 | goto out_putf; | |
176 | ||
14da9200 | 177 | sb_start_write(inode->i_sb); |
2903ff01 | 178 | error = locks_verify_truncate(inode, f.file, length); |
be6d3e56 | 179 | if (!error) |
2903ff01 | 180 | error = security_path_truncate(&f.file->f_path); |
1da177e4 | 181 | if (!error) |
2903ff01 | 182 | error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, f.file); |
14da9200 | 183 | sb_end_write(inode->i_sb); |
1da177e4 | 184 | out_putf: |
2903ff01 | 185 | fdput(f); |
1da177e4 LT |
186 | out: |
187 | return error; | |
188 | } | |
189 | ||
bdc480e3 | 190 | SYSCALL_DEFINE2(ftruncate, unsigned int, fd, unsigned long, length) |
1da177e4 | 191 | { |
0a489cb3 | 192 | long ret = do_sys_ftruncate(fd, length, 1); |
385910f2 | 193 | /* avoid REGPARM breakage on x86: */ |
54a01510 | 194 | asmlinkage_protect(2, ret, fd, length); |
0a489cb3 | 195 | return ret; |
1da177e4 LT |
196 | } |
197 | ||
198 | /* LFS versions of truncate are only needed on 32 bit machines */ | |
199 | #if BITS_PER_LONG == 32 | |
6673e0c3 | 200 | SYSCALL_DEFINE(truncate64)(const char __user * path, loff_t length) |
1da177e4 LT |
201 | { |
202 | return do_sys_truncate(path, length); | |
203 | } | |
6673e0c3 HC |
204 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
205 | asmlinkage long SyS_truncate64(long path, loff_t length) | |
206 | { | |
207 | return SYSC_truncate64((const char __user *) path, length); | |
208 | } | |
209 | SYSCALL_ALIAS(sys_truncate64, SyS_truncate64); | |
210 | #endif | |
1da177e4 | 211 | |
6673e0c3 | 212 | SYSCALL_DEFINE(ftruncate64)(unsigned int fd, loff_t length) |
1da177e4 | 213 | { |
0a489cb3 | 214 | long ret = do_sys_ftruncate(fd, length, 0); |
385910f2 | 215 | /* avoid REGPARM breakage on x86: */ |
54a01510 | 216 | asmlinkage_protect(2, ret, fd, length); |
0a489cb3 | 217 | return ret; |
1da177e4 | 218 | } |
6673e0c3 HC |
219 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
220 | asmlinkage long SyS_ftruncate64(long fd, loff_t length) | |
221 | { | |
222 | return SYSC_ftruncate64((unsigned int) fd, length); | |
223 | } | |
224 | SYSCALL_ALIAS(sys_ftruncate64, SyS_ftruncate64); | |
1da177e4 | 225 | #endif |
6673e0c3 | 226 | #endif /* BITS_PER_LONG == 32 */ |
1da177e4 | 227 | |
3e63cbb1 AJ |
228 | |
229 | int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len) | |
97ac7350 | 230 | { |
3e63cbb1 AJ |
231 | struct inode *inode = file->f_path.dentry->d_inode; |
232 | long ret; | |
97ac7350 AA |
233 | |
234 | if (offset < 0 || len <= 0) | |
3e63cbb1 | 235 | return -EINVAL; |
97ac7350 AA |
236 | |
237 | /* Return error if mode is not supported */ | |
79124f18 JB |
238 | if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) |
239 | return -EOPNOTSUPP; | |
240 | ||
241 | /* Punch hole must have keep size set */ | |
242 | if ((mode & FALLOC_FL_PUNCH_HOLE) && | |
243 | !(mode & FALLOC_FL_KEEP_SIZE)) | |
3e63cbb1 | 244 | return -EOPNOTSUPP; |
97ac7350 | 245 | |
97ac7350 | 246 | if (!(file->f_mode & FMODE_WRITE)) |
3e63cbb1 | 247 | return -EBADF; |
1ca551c6 MS |
248 | |
249 | /* It's not possible punch hole on append only file */ | |
250 | if (mode & FALLOC_FL_PUNCH_HOLE && IS_APPEND(inode)) | |
251 | return -EPERM; | |
252 | ||
253 | if (IS_IMMUTABLE(inode)) | |
254 | return -EPERM; | |
255 | ||
97ac7350 AA |
256 | /* |
257 | * Revalidate the write permissions, in case security policy has | |
258 | * changed since the files were opened. | |
259 | */ | |
260 | ret = security_file_permission(file, MAY_WRITE); | |
261 | if (ret) | |
3e63cbb1 | 262 | return ret; |
97ac7350 | 263 | |
97ac7350 | 264 | if (S_ISFIFO(inode->i_mode)) |
3e63cbb1 | 265 | return -ESPIPE; |
97ac7350 | 266 | |
97ac7350 AA |
267 | /* |
268 | * Let individual file system decide if it supports preallocation | |
269 | * for directories or not. | |
270 | */ | |
271 | if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) | |
3e63cbb1 | 272 | return -ENODEV; |
97ac7350 | 273 | |
97ac7350 AA |
274 | /* Check for wrap through zero too */ |
275 | if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0)) | |
3e63cbb1 | 276 | return -EFBIG; |
97ac7350 | 277 | |
2fe17c10 | 278 | if (!file->f_op->fallocate) |
3e63cbb1 | 279 | return -EOPNOTSUPP; |
97ac7350 | 280 | |
14da9200 JK |
281 | sb_start_write(inode->i_sb); |
282 | ret = file->f_op->fallocate(file, mode, offset, len); | |
283 | sb_end_write(inode->i_sb); | |
284 | return ret; | |
3e63cbb1 AJ |
285 | } |
286 | ||
287 | SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len) | |
288 | { | |
2903ff01 | 289 | struct fd f = fdget(fd); |
3e63cbb1 AJ |
290 | int error = -EBADF; |
291 | ||
2903ff01 AV |
292 | if (f.file) { |
293 | error = do_fallocate(f.file, mode, offset, len); | |
294 | fdput(f); | |
3e63cbb1 | 295 | } |
3e63cbb1 | 296 | return error; |
97ac7350 | 297 | } |
3e63cbb1 | 298 | |
6673e0c3 HC |
299 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
300 | asmlinkage long SyS_fallocate(long fd, long mode, loff_t offset, loff_t len) | |
301 | { | |
302 | return SYSC_fallocate((int)fd, (int)mode, offset, len); | |
303 | } | |
304 | SYSCALL_ALIAS(sys_fallocate, SyS_fallocate); | |
305 | #endif | |
97ac7350 | 306 | |
1da177e4 LT |
307 | /* |
308 | * access() needs to use the real uid/gid, not the effective uid/gid. | |
309 | * We do this by temporarily clearing all FS-related capabilities and | |
310 | * switching the fsuid/fsgid around to the real ones. | |
311 | */ | |
6559eed8 | 312 | SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode) |
1da177e4 | 313 | { |
d84f4f99 DH |
314 | const struct cred *old_cred; |
315 | struct cred *override_cred; | |
2d8f3038 | 316 | struct path path; |
256984a8 | 317 | struct inode *inode; |
1da177e4 | 318 | int res; |
87fa5595 | 319 | unsigned int lookup_flags = LOOKUP_FOLLOW; |
1da177e4 LT |
320 | |
321 | if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */ | |
322 | return -EINVAL; | |
323 | ||
d84f4f99 DH |
324 | override_cred = prepare_creds(); |
325 | if (!override_cred) | |
326 | return -ENOMEM; | |
1da177e4 | 327 | |
d84f4f99 DH |
328 | override_cred->fsuid = override_cred->uid; |
329 | override_cred->fsgid = override_cred->gid; | |
1da177e4 | 330 | |
086f7316 | 331 | if (!issecure(SECURE_NO_SETUID_FIXUP)) { |
1cdcbec1 | 332 | /* Clear the capabilities if we switch to a non-root user */ |
18815a18 EB |
333 | kuid_t root_uid = make_kuid(override_cred->user_ns, 0); |
334 | if (!uid_eq(override_cred->uid, root_uid)) | |
d84f4f99 | 335 | cap_clear(override_cred->cap_effective); |
086f7316 | 336 | else |
d84f4f99 DH |
337 | override_cred->cap_effective = |
338 | override_cred->cap_permitted; | |
086f7316 | 339 | } |
1da177e4 | 340 | |
d84f4f99 | 341 | old_cred = override_creds(override_cred); |
87fa5595 JL |
342 | retry: |
343 | res = user_path_at(dfd, filename, lookup_flags, &path); | |
6902d925 DH |
344 | if (res) |
345 | goto out; | |
346 | ||
2d8f3038 | 347 | inode = path.dentry->d_inode; |
256984a8 AV |
348 | |
349 | if ((mode & MAY_EXEC) && S_ISREG(inode->i_mode)) { | |
30524472 AV |
350 | /* |
351 | * MAY_EXEC on regular files is denied if the fs is mounted | |
352 | * with the "noexec" flag. | |
353 | */ | |
354 | res = -EACCES; | |
2d8f3038 | 355 | if (path.mnt->mnt_flags & MNT_NOEXEC) |
30524472 AV |
356 | goto out_path_release; |
357 | } | |
358 | ||
256984a8 | 359 | res = inode_permission(inode, mode | MAY_ACCESS); |
6902d925 | 360 | /* SuS v2 requires we report a read only fs too */ |
256984a8 | 361 | if (res || !(mode & S_IWOTH) || special_file(inode->i_mode)) |
6902d925 | 362 | goto out_path_release; |
2f676cbc DH |
363 | /* |
364 | * This is a rare case where using __mnt_is_readonly() | |
365 | * is OK without a mnt_want/drop_write() pair. Since | |
366 | * no actual write to the fs is performed here, we do | |
367 | * not need to telegraph to that to anyone. | |
368 | * | |
369 | * By doing this, we accept that this access is | |
370 | * inherently racy and know that the fs may change | |
371 | * state before we even see this result. | |
372 | */ | |
2d8f3038 | 373 | if (__mnt_is_readonly(path.mnt)) |
6902d925 | 374 | res = -EROFS; |
1da177e4 | 375 | |
6902d925 | 376 | out_path_release: |
2d8f3038 | 377 | path_put(&path); |
87fa5595 JL |
378 | if (retry_estale(res, lookup_flags)) { |
379 | lookup_flags |= LOOKUP_REVAL; | |
380 | goto retry; | |
381 | } | |
6902d925 | 382 | out: |
d84f4f99 DH |
383 | revert_creds(old_cred); |
384 | put_cred(override_cred); | |
1da177e4 LT |
385 | return res; |
386 | } | |
387 | ||
ca013e94 | 388 | SYSCALL_DEFINE2(access, const char __user *, filename, int, mode) |
5590ff0d UD |
389 | { |
390 | return sys_faccessat(AT_FDCWD, filename, mode); | |
391 | } | |
392 | ||
3cdad428 | 393 | SYSCALL_DEFINE1(chdir, const char __user *, filename) |
1da177e4 | 394 | { |
2d8f3038 | 395 | struct path path; |
1da177e4 LT |
396 | int error; |
397 | ||
2d8f3038 | 398 | error = user_path_dir(filename, &path); |
1da177e4 LT |
399 | if (error) |
400 | goto out; | |
401 | ||
9cfcac81 | 402 | error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); |
1da177e4 LT |
403 | if (error) |
404 | goto dput_and_out; | |
405 | ||
2d8f3038 | 406 | set_fs_pwd(current->fs, &path); |
1da177e4 LT |
407 | |
408 | dput_and_out: | |
2d8f3038 | 409 | path_put(&path); |
1da177e4 LT |
410 | out: |
411 | return error; | |
412 | } | |
413 | ||
3cdad428 | 414 | SYSCALL_DEFINE1(fchdir, unsigned int, fd) |
1da177e4 | 415 | { |
2903ff01 | 416 | struct fd f = fdget_raw(fd); |
1da177e4 | 417 | struct inode *inode; |
2903ff01 | 418 | int error = -EBADF; |
1da177e4 LT |
419 | |
420 | error = -EBADF; | |
2903ff01 | 421 | if (!f.file) |
1da177e4 LT |
422 | goto out; |
423 | ||
2903ff01 | 424 | inode = f.file->f_path.dentry->d_inode; |
1da177e4 LT |
425 | |
426 | error = -ENOTDIR; | |
427 | if (!S_ISDIR(inode->i_mode)) | |
428 | goto out_putf; | |
429 | ||
9cfcac81 | 430 | error = inode_permission(inode, MAY_EXEC | MAY_CHDIR); |
1da177e4 | 431 | if (!error) |
2903ff01 | 432 | set_fs_pwd(current->fs, &f.file->f_path); |
1da177e4 | 433 | out_putf: |
2903ff01 | 434 | fdput(f); |
1da177e4 LT |
435 | out: |
436 | return error; | |
437 | } | |
438 | ||
3480b257 | 439 | SYSCALL_DEFINE1(chroot, const char __user *, filename) |
1da177e4 | 440 | { |
2d8f3038 | 441 | struct path path; |
1da177e4 LT |
442 | int error; |
443 | ||
2d8f3038 | 444 | error = user_path_dir(filename, &path); |
1da177e4 LT |
445 | if (error) |
446 | goto out; | |
447 | ||
9cfcac81 | 448 | error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); |
1da177e4 LT |
449 | if (error) |
450 | goto dput_and_out; | |
451 | ||
452 | error = -EPERM; | |
a85fb273 | 453 | if (!nsown_capable(CAP_SYS_CHROOT)) |
1da177e4 | 454 | goto dput_and_out; |
8b8efb44 TH |
455 | error = security_path_chroot(&path); |
456 | if (error) | |
457 | goto dput_and_out; | |
1da177e4 | 458 | |
2d8f3038 | 459 | set_fs_root(current->fs, &path); |
1da177e4 LT |
460 | error = 0; |
461 | dput_and_out: | |
2d8f3038 | 462 | path_put(&path); |
1da177e4 LT |
463 | out: |
464 | return error; | |
465 | } | |
466 | ||
e57712eb | 467 | static int chmod_common(struct path *path, umode_t mode) |
1da177e4 | 468 | { |
e57712eb | 469 | struct inode *inode = path->dentry->d_inode; |
1da177e4 | 470 | struct iattr newattrs; |
e57712eb | 471 | int error; |
1da177e4 | 472 | |
e57712eb AV |
473 | error = mnt_want_write(path->mnt); |
474 | if (error) | |
475 | return error; | |
fe542cf5 | 476 | mutex_lock(&inode->i_mutex); |
cdcf116d | 477 | error = security_path_chmod(path, mode); |
e57712eb | 478 | if (error) |
fe542cf5 | 479 | goto out_unlock; |
1da177e4 LT |
480 | newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); |
481 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; | |
e57712eb | 482 | error = notify_change(path->dentry, &newattrs); |
fe542cf5 | 483 | out_unlock: |
1b1dcc1b | 484 | mutex_unlock(&inode->i_mutex); |
e57712eb AV |
485 | mnt_drop_write(path->mnt); |
486 | return error; | |
487 | } | |
488 | ||
49f0a076 | 489 | SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode) |
e57712eb AV |
490 | { |
491 | struct file * file; | |
492 | int err = -EBADF; | |
493 | ||
494 | file = fget(fd); | |
495 | if (file) { | |
bfcec708 | 496 | audit_inode(NULL, file->f_path.dentry, 0); |
e57712eb AV |
497 | err = chmod_common(&file->f_path, mode); |
498 | fput(file); | |
499 | } | |
1da177e4 LT |
500 | return err; |
501 | } | |
502 | ||
49f0a076 | 503 | SYSCALL_DEFINE3(fchmodat, int, dfd, const char __user *, filename, umode_t, mode) |
1da177e4 | 504 | { |
2d8f3038 | 505 | struct path path; |
1da177e4 | 506 | int error; |
1da177e4 | 507 | |
2d8f3038 | 508 | error = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path); |
e57712eb AV |
509 | if (!error) { |
510 | error = chmod_common(&path, mode); | |
511 | path_put(&path); | |
512 | } | |
1da177e4 LT |
513 | return error; |
514 | } | |
515 | ||
49f0a076 | 516 | SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode) |
5590ff0d UD |
517 | { |
518 | return sys_fchmodat(AT_FDCWD, filename, mode); | |
519 | } | |
520 | ||
fe542cf5 | 521 | static int chown_common(struct path *path, uid_t user, gid_t group) |
1da177e4 | 522 | { |
fe542cf5 | 523 | struct inode *inode = path->dentry->d_inode; |
1da177e4 LT |
524 | int error; |
525 | struct iattr newattrs; | |
52137abe EB |
526 | kuid_t uid; |
527 | kgid_t gid; | |
528 | ||
529 | uid = make_kuid(current_user_ns(), user); | |
530 | gid = make_kgid(current_user_ns(), group); | |
1da177e4 | 531 | |
1da177e4 LT |
532 | newattrs.ia_valid = ATTR_CTIME; |
533 | if (user != (uid_t) -1) { | |
52137abe EB |
534 | if (!uid_valid(uid)) |
535 | return -EINVAL; | |
1da177e4 | 536 | newattrs.ia_valid |= ATTR_UID; |
52137abe | 537 | newattrs.ia_uid = uid; |
1da177e4 LT |
538 | } |
539 | if (group != (gid_t) -1) { | |
52137abe EB |
540 | if (!gid_valid(gid)) |
541 | return -EINVAL; | |
1da177e4 | 542 | newattrs.ia_valid |= ATTR_GID; |
52137abe | 543 | newattrs.ia_gid = gid; |
1da177e4 LT |
544 | } |
545 | if (!S_ISDIR(inode->i_mode)) | |
b5376771 SH |
546 | newattrs.ia_valid |= |
547 | ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV; | |
1b1dcc1b | 548 | mutex_lock(&inode->i_mutex); |
d2b31ca6 | 549 | error = security_path_chown(path, uid, gid); |
fe542cf5 TH |
550 | if (!error) |
551 | error = notify_change(path->dentry, &newattrs); | |
1b1dcc1b | 552 | mutex_unlock(&inode->i_mutex); |
beb29e05 | 553 | |
1da177e4 LT |
554 | return error; |
555 | } | |
556 | ||
6559eed8 HC |
557 | SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user, |
558 | gid_t, group, int, flag) | |
5590ff0d | 559 | { |
2d8f3038 | 560 | struct path path; |
5590ff0d | 561 | int error = -EINVAL; |
65cfc672 | 562 | int lookup_flags; |
5590ff0d | 563 | |
65cfc672 | 564 | if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) |
5590ff0d UD |
565 | goto out; |
566 | ||
65cfc672 AV |
567 | lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; |
568 | if (flag & AT_EMPTY_PATH) | |
569 | lookup_flags |= LOOKUP_EMPTY; | |
570 | error = user_path_at(dfd, filename, lookup_flags, &path); | |
6902d925 DH |
571 | if (error) |
572 | goto out; | |
2d8f3038 | 573 | error = mnt_want_write(path.mnt); |
2af482a7 DH |
574 | if (error) |
575 | goto out_release; | |
fe542cf5 | 576 | error = chown_common(&path, user, group); |
2d8f3038 | 577 | mnt_drop_write(path.mnt); |
2af482a7 | 578 | out_release: |
2d8f3038 | 579 | path_put(&path); |
5590ff0d UD |
580 | out: |
581 | return error; | |
582 | } | |
583 | ||
55e4def0 | 584 | SYSCALL_DEFINE3(chown, const char __user *, filename, uid_t, user, gid_t, group) |
1da177e4 | 585 | { |
55e4def0 DH |
586 | return sys_fchownat(AT_FDCWD, filename, user, group, 0); |
587 | } | |
1da177e4 | 588 | |
55e4def0 DH |
589 | SYSCALL_DEFINE3(lchown, const char __user *, filename, uid_t, user, gid_t, group) |
590 | { | |
591 | return sys_fchownat(AT_FDCWD, filename, user, group, | |
592 | AT_SYMLINK_NOFOLLOW); | |
1da177e4 LT |
593 | } |
594 | ||
ca013e94 | 595 | SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group) |
1da177e4 | 596 | { |
2903ff01 | 597 | struct fd f = fdget(fd); |
1da177e4 LT |
598 | int error = -EBADF; |
599 | ||
2903ff01 | 600 | if (!f.file) |
6902d925 DH |
601 | goto out; |
602 | ||
2903ff01 | 603 | error = mnt_want_write_file(f.file); |
2af482a7 DH |
604 | if (error) |
605 | goto out_fput; | |
bfcec708 | 606 | audit_inode(NULL, f.file->f_path.dentry, 0); |
2903ff01 AV |
607 | error = chown_common(&f.file->f_path, user, group); |
608 | mnt_drop_write_file(f.file); | |
2af482a7 | 609 | out_fput: |
2903ff01 | 610 | fdput(f); |
6902d925 | 611 | out: |
1da177e4 LT |
612 | return error; |
613 | } | |
614 | ||
4a3fd211 DH |
615 | /* |
616 | * You have to be very careful that these write | |
617 | * counts get cleaned up in error cases and | |
618 | * upon __fput(). This should probably never | |
619 | * be called outside of __dentry_open(). | |
620 | */ | |
621 | static inline int __get_file_write_access(struct inode *inode, | |
622 | struct vfsmount *mnt) | |
623 | { | |
624 | int error; | |
625 | error = get_write_access(inode); | |
626 | if (error) | |
627 | return error; | |
628 | /* | |
629 | * Do not take mount writer counts on | |
630 | * special files since no writes to | |
631 | * the mount itself will occur. | |
632 | */ | |
633 | if (!special_file(inode->i_mode)) { | |
634 | /* | |
635 | * Balanced in __fput() | |
636 | */ | |
eb04c282 | 637 | error = __mnt_want_write(mnt); |
4a3fd211 DH |
638 | if (error) |
639 | put_write_access(inode); | |
640 | } | |
641 | return error; | |
642 | } | |
643 | ||
90ad1a8e MS |
644 | int open_check_o_direct(struct file *f) |
645 | { | |
646 | /* NB: we're sure to have correct a_ops only after f_op->open */ | |
647 | if (f->f_flags & O_DIRECT) { | |
648 | if (!f->f_mapping->a_ops || | |
649 | ((!f->f_mapping->a_ops->direct_IO) && | |
650 | (!f->f_mapping->a_ops->get_xip_mem))) { | |
651 | return -EINVAL; | |
652 | } | |
653 | } | |
654 | return 0; | |
655 | } | |
656 | ||
02e5180d | 657 | static int do_dentry_open(struct file *f, |
96b7e579 AV |
658 | int (*open)(struct inode *, struct file *), |
659 | const struct cred *cred) | |
1da177e4 | 660 | { |
1abf0c71 | 661 | static const struct file_operations empty_fops = {}; |
1da177e4 LT |
662 | struct inode *inode; |
663 | int error; | |
664 | ||
5300990c | 665 | f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | |
a1a5b3d9 | 666 | FMODE_PREAD | FMODE_PWRITE; |
1abf0c71 AV |
667 | |
668 | if (unlikely(f->f_flags & O_PATH)) | |
669 | f->f_mode = FMODE_PATH; | |
670 | ||
b5bcdda3 | 671 | path_get(&f->f_path); |
02e5180d | 672 | inode = f->f_path.dentry->d_inode; |
1da177e4 | 673 | if (f->f_mode & FMODE_WRITE) { |
02e5180d | 674 | error = __get_file_write_access(inode, f->f_path.mnt); |
1da177e4 LT |
675 | if (error) |
676 | goto cleanup_file; | |
ad775f5a DH |
677 | if (!special_file(inode->i_mode)) |
678 | file_take_write(f); | |
1da177e4 LT |
679 | } |
680 | ||
681 | f->f_mapping = inode->i_mapping; | |
1da177e4 | 682 | f->f_pos = 0; |
ee2ffa0d | 683 | file_sb_list_add(f, inode->i_sb); |
1da177e4 | 684 | |
1abf0c71 AV |
685 | if (unlikely(f->f_mode & FMODE_PATH)) { |
686 | f->f_op = &empty_fops; | |
96b7e579 | 687 | return 0; |
1abf0c71 AV |
688 | } |
689 | ||
690 | f->f_op = fops_get(inode->i_fop); | |
691 | ||
83d49856 | 692 | error = security_file_open(f, cred); |
788e7dd4 YN |
693 | if (error) |
694 | goto cleanup_all; | |
695 | ||
f3c7691e BF |
696 | error = break_lease(inode, f->f_flags); |
697 | if (error) | |
698 | goto cleanup_all; | |
699 | ||
834f2a4a TM |
700 | if (!open && f->f_op) |
701 | open = f->f_op->open; | |
702 | if (open) { | |
703 | error = open(inode, f); | |
1da177e4 LT |
704 | if (error) |
705 | goto cleanup_all; | |
706 | } | |
890275b5 MZ |
707 | if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) |
708 | i_readcount_inc(inode); | |
834f2a4a | 709 | |
1da177e4 LT |
710 | f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); |
711 | ||
712 | file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); | |
713 | ||
96b7e579 | 714 | return 0; |
1da177e4 LT |
715 | |
716 | cleanup_all: | |
717 | fops_put(f->f_op); | |
c3c4f694 | 718 | file_sb_list_del(f); |
4a3fd211 | 719 | if (f->f_mode & FMODE_WRITE) { |
1da177e4 | 720 | put_write_access(inode); |
ad775f5a DH |
721 | if (!special_file(inode->i_mode)) { |
722 | /* | |
723 | * We don't consider this a real | |
724 | * mnt_want/drop_write() pair | |
725 | * because it all happenend right | |
726 | * here, so just reset the state. | |
727 | */ | |
728 | file_reset_write(f); | |
fe7c8051 | 729 | __mnt_drop_write(f->f_path.mnt); |
ad775f5a | 730 | } |
4a3fd211 | 731 | } |
1da177e4 | 732 | cleanup_file: |
02e5180d AV |
733 | path_put(&f->f_path); |
734 | f->f_path.mnt = NULL; | |
735 | f->f_path.dentry = NULL; | |
96b7e579 | 736 | return error; |
1da177e4 LT |
737 | } |
738 | ||
d18e9008 MS |
739 | /** |
740 | * finish_open - finish opening a file | |
741 | * @od: opaque open data | |
742 | * @dentry: pointer to dentry | |
743 | * @open: open callback | |
744 | * | |
745 | * This can be used to finish opening a file passed to i_op->atomic_open(). | |
746 | * | |
747 | * If the open callback is set to NULL, then the standard f_op->open() | |
748 | * filesystem callback is substituted. | |
749 | */ | |
30d90494 AV |
750 | int finish_open(struct file *file, struct dentry *dentry, |
751 | int (*open)(struct inode *, struct file *), | |
752 | int *opened) | |
d18e9008 | 753 | { |
96b7e579 | 754 | int error; |
3d8a00d2 | 755 | BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */ |
d18e9008 | 756 | |
b5bcdda3 | 757 | file->f_path.dentry = dentry; |
02e5180d | 758 | error = do_dentry_open(file, open, current_cred()); |
96b7e579 | 759 | if (!error) |
47237687 | 760 | *opened |= FILE_OPENED; |
d18e9008 | 761 | |
96b7e579 | 762 | return error; |
d18e9008 MS |
763 | } |
764 | EXPORT_SYMBOL(finish_open); | |
765 | ||
766 | /** | |
767 | * finish_no_open - finish ->atomic_open() without opening the file | |
768 | * | |
769 | * @od: opaque open data | |
770 | * @dentry: dentry or NULL (as returned from ->lookup()) | |
771 | * | |
772 | * This can be used to set the result of a successful lookup in ->atomic_open(). | |
773 | * The filesystem's atomic_open() method shall return NULL after calling this. | |
774 | */ | |
e45198a6 | 775 | int finish_no_open(struct file *file, struct dentry *dentry) |
d18e9008 | 776 | { |
30d90494 | 777 | file->f_path.dentry = dentry; |
e45198a6 | 778 | return 1; |
d18e9008 MS |
779 | } |
780 | EXPORT_SYMBOL(finish_no_open); | |
781 | ||
765927b2 | 782 | struct file *dentry_open(const struct path *path, int flags, |
745ca247 | 783 | const struct cred *cred) |
a1a5b3d9 PS |
784 | { |
785 | int error; | |
786 | struct file *f; | |
787 | ||
e0e81739 DH |
788 | validate_creds(cred); |
789 | ||
c212f9aa | 790 | /* We must always pass in a valid mount pointer. */ |
765927b2 | 791 | BUG_ON(!path->mnt); |
322ee5b3 | 792 | |
a1a5b3d9 PS |
793 | error = -ENFILE; |
794 | f = get_empty_filp(); | |
765927b2 | 795 | if (f == NULL) |
a1a5b3d9 PS |
796 | return ERR_PTR(error); |
797 | ||
482928d5 | 798 | f->f_flags = flags; |
765927b2 | 799 | f->f_path = *path; |
02e5180d | 800 | error = do_dentry_open(f, NULL, cred); |
2a027e7a AV |
801 | if (!error) { |
802 | error = open_check_o_direct(f); | |
803 | if (error) { | |
804 | fput(f); | |
805 | f = ERR_PTR(error); | |
806 | } | |
807 | } else { | |
808 | put_filp(f); | |
809 | f = ERR_PTR(error); | |
810 | } | |
811 | return f; | |
a1a5b3d9 | 812 | } |
1da177e4 LT |
813 | EXPORT_SYMBOL(dentry_open); |
814 | ||
a218d0fd | 815 | static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op) |
47c805dc AV |
816 | { |
817 | int lookup_flags = 0; | |
818 | int acc_mode; | |
819 | ||
e68726ff MS |
820 | if (flags & O_CREAT) |
821 | op->mode = (mode & S_IALLUGO) | S_IFREG; | |
822 | else | |
823 | op->mode = 0; | |
47c805dc AV |
824 | |
825 | /* Must never be set by userspace */ | |
c6f3d811 | 826 | flags &= ~FMODE_NONOTIFY & ~O_CLOEXEC; |
47c805dc AV |
827 | |
828 | /* | |
829 | * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only | |
830 | * check for O_DSYNC if the need any syncing at all we enforce it's | |
831 | * always set instead of having to deal with possibly weird behaviour | |
832 | * for malicious applications setting only __O_SYNC. | |
833 | */ | |
834 | if (flags & __O_SYNC) | |
835 | flags |= O_DSYNC; | |
836 | ||
1abf0c71 AV |
837 | /* |
838 | * If we have O_PATH in the open flag. Then we | |
839 | * cannot have anything other than the below set of flags | |
840 | */ | |
841 | if (flags & O_PATH) { | |
842 | flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH; | |
843 | acc_mode = 0; | |
844 | } else { | |
845 | acc_mode = MAY_OPEN | ACC_MODE(flags); | |
846 | } | |
47c805dc | 847 | |
1abf0c71 | 848 | op->open_flag = flags; |
47c805dc AV |
849 | |
850 | /* O_TRUNC implies we need access checks for write permissions */ | |
851 | if (flags & O_TRUNC) | |
852 | acc_mode |= MAY_WRITE; | |
853 | ||
854 | /* Allow the LSM permission hook to distinguish append | |
855 | access from general write access. */ | |
856 | if (flags & O_APPEND) | |
857 | acc_mode |= MAY_APPEND; | |
858 | ||
859 | op->acc_mode = acc_mode; | |
860 | ||
1abf0c71 AV |
861 | op->intent = flags & O_PATH ? 0 : LOOKUP_OPEN; |
862 | ||
47c805dc AV |
863 | if (flags & O_CREAT) { |
864 | op->intent |= LOOKUP_CREATE; | |
865 | if (flags & O_EXCL) | |
866 | op->intent |= LOOKUP_EXCL; | |
867 | } | |
868 | ||
869 | if (flags & O_DIRECTORY) | |
870 | lookup_flags |= LOOKUP_DIRECTORY; | |
871 | if (!(flags & O_NOFOLLOW)) | |
872 | lookup_flags |= LOOKUP_FOLLOW; | |
873 | return lookup_flags; | |
874 | } | |
875 | ||
669abf4e JL |
876 | /** |
877 | * file_open_name - open file and return file pointer | |
878 | * | |
879 | * @name: struct filename containing path to open | |
880 | * @flags: open flags as per the open(2) second argument | |
881 | * @mode: mode for the new file if O_CREAT is set, else ignored | |
882 | * | |
883 | * This is the helper to open a file from kernelspace if you really | |
884 | * have to. But in generally you should not do this, so please move | |
885 | * along, nothing to see here.. | |
886 | */ | |
887 | struct file *file_open_name(struct filename *name, int flags, umode_t mode) | |
888 | { | |
889 | struct open_flags op; | |
890 | int lookup = build_open_flags(flags, mode, &op); | |
891 | return do_filp_open(AT_FDCWD, name, &op, lookup); | |
892 | } | |
893 | ||
47c805dc AV |
894 | /** |
895 | * filp_open - open file and return file pointer | |
896 | * | |
897 | * @filename: path to open | |
898 | * @flags: open flags as per the open(2) second argument | |
899 | * @mode: mode for the new file if O_CREAT is set, else ignored | |
900 | * | |
901 | * This is the helper to open a file from kernelspace if you really | |
902 | * have to. But in generally you should not do this, so please move | |
903 | * along, nothing to see here.. | |
904 | */ | |
a218d0fd | 905 | struct file *filp_open(const char *filename, int flags, umode_t mode) |
47c805dc | 906 | { |
669abf4e JL |
907 | struct filename name = {.name = filename}; |
908 | return file_open_name(&name, flags, mode); | |
47c805dc AV |
909 | } |
910 | EXPORT_SYMBOL(filp_open); | |
911 | ||
73d049a4 AV |
912 | struct file *file_open_root(struct dentry *dentry, struct vfsmount *mnt, |
913 | const char *filename, int flags) | |
914 | { | |
915 | struct open_flags op; | |
916 | int lookup = build_open_flags(flags, 0, &op); | |
917 | if (flags & O_CREAT) | |
918 | return ERR_PTR(-EINVAL); | |
919 | if (!filename && (flags & O_DIRECTORY)) | |
920 | if (!dentry->d_inode->i_op->lookup) | |
921 | return ERR_PTR(-ENOTDIR); | |
922 | return do_file_open_root(dentry, mnt, filename, &op, lookup); | |
923 | } | |
924 | EXPORT_SYMBOL(file_open_root); | |
925 | ||
a218d0fd | 926 | long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode) |
1da177e4 | 927 | { |
47c805dc AV |
928 | struct open_flags op; |
929 | int lookup = build_open_flags(flags, mode, &op); | |
91a27b2a | 930 | struct filename *tmp = getname(filename); |
e922efc3 | 931 | int fd = PTR_ERR(tmp); |
1da177e4 | 932 | |
1da177e4 | 933 | if (!IS_ERR(tmp)) { |
f23513e8 | 934 | fd = get_unused_fd_flags(flags); |
1da177e4 | 935 | if (fd >= 0) { |
669abf4e | 936 | struct file *f = do_filp_open(dfd, tmp, &op, lookup); |
fed2fc18 TN |
937 | if (IS_ERR(f)) { |
938 | put_unused_fd(fd); | |
939 | fd = PTR_ERR(f); | |
940 | } else { | |
2a12a9d7 | 941 | fsnotify_open(f); |
fed2fc18 TN |
942 | fd_install(fd, f); |
943 | } | |
1da177e4 | 944 | } |
1da177e4 LT |
945 | putname(tmp); |
946 | } | |
947 | return fd; | |
1da177e4 | 948 | } |
e922efc3 | 949 | |
a218d0fd | 950 | SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode) |
e922efc3 | 951 | { |
385910f2 LT |
952 | long ret; |
953 | ||
e922efc3 MS |
954 | if (force_o_largefile()) |
955 | flags |= O_LARGEFILE; | |
956 | ||
385910f2 LT |
957 | ret = do_sys_open(AT_FDCWD, filename, flags, mode); |
958 | /* avoid REGPARM breakage on x86: */ | |
54a01510 | 959 | asmlinkage_protect(3, ret, filename, flags, mode); |
385910f2 | 960 | return ret; |
e922efc3 | 961 | } |
1da177e4 | 962 | |
6559eed8 | 963 | SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags, |
a218d0fd | 964 | umode_t, mode) |
5590ff0d | 965 | { |
385910f2 LT |
966 | long ret; |
967 | ||
5590ff0d UD |
968 | if (force_o_largefile()) |
969 | flags |= O_LARGEFILE; | |
970 | ||
385910f2 LT |
971 | ret = do_sys_open(dfd, filename, flags, mode); |
972 | /* avoid REGPARM breakage on x86: */ | |
54a01510 | 973 | asmlinkage_protect(4, ret, dfd, filename, flags, mode); |
385910f2 | 974 | return ret; |
5590ff0d | 975 | } |
5590ff0d | 976 | |
1da177e4 LT |
977 | #ifndef __alpha__ |
978 | ||
979 | /* | |
980 | * For backward compatibility? Maybe this should be moved | |
981 | * into arch/i386 instead? | |
982 | */ | |
a218d0fd | 983 | SYSCALL_DEFINE2(creat, const char __user *, pathname, umode_t, mode) |
1da177e4 LT |
984 | { |
985 | return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode); | |
986 | } | |
987 | ||
988 | #endif | |
989 | ||
990 | /* | |
991 | * "id" is the POSIX thread ID. We use the | |
992 | * files pointer for this.. | |
993 | */ | |
994 | int filp_close(struct file *filp, fl_owner_t id) | |
995 | { | |
45778ca8 | 996 | int retval = 0; |
1da177e4 LT |
997 | |
998 | if (!file_count(filp)) { | |
999 | printk(KERN_ERR "VFS: Close: file count is 0\n"); | |
45778ca8 | 1000 | return 0; |
1da177e4 LT |
1001 | } |
1002 | ||
45778ca8 | 1003 | if (filp->f_op && filp->f_op->flush) |
75e1fcc0 | 1004 | retval = filp->f_op->flush(filp, id); |
1da177e4 | 1005 | |
1abf0c71 AV |
1006 | if (likely(!(filp->f_mode & FMODE_PATH))) { |
1007 | dnotify_flush(filp, id); | |
1008 | locks_remove_posix(filp, id); | |
1009 | } | |
1da177e4 LT |
1010 | fput(filp); |
1011 | return retval; | |
1012 | } | |
1013 | ||
1014 | EXPORT_SYMBOL(filp_close); | |
1015 | ||
1016 | /* | |
1017 | * Careful here! We test whether the file pointer is NULL before | |
1018 | * releasing the fd. This ensures that one clone task can't release | |
1019 | * an fd while another clone is opening it. | |
1020 | */ | |
ca013e94 | 1021 | SYSCALL_DEFINE1(close, unsigned int, fd) |
1da177e4 | 1022 | { |
483ce1d4 | 1023 | int retval = __close_fd(current->files, fd); |
ee731f4f EP |
1024 | |
1025 | /* can't restart close syscall because file table entry was cleared */ | |
1026 | if (unlikely(retval == -ERESTARTSYS || | |
1027 | retval == -ERESTARTNOINTR || | |
1028 | retval == -ERESTARTNOHAND || | |
1029 | retval == -ERESTART_RESTARTBLOCK)) | |
1030 | retval = -EINTR; | |
1031 | ||
1032 | return retval; | |
1da177e4 | 1033 | } |
1da177e4 LT |
1034 | EXPORT_SYMBOL(sys_close); |
1035 | ||
1036 | /* | |
1037 | * This routine simulates a hangup on the tty, to arrange that users | |
1038 | * are given clean terminals at login time. | |
1039 | */ | |
ca013e94 | 1040 | SYSCALL_DEFINE0(vhangup) |
1da177e4 LT |
1041 | { |
1042 | if (capable(CAP_SYS_TTY_CONFIG)) { | |
2cb5998b | 1043 | tty_vhangup_self(); |
1da177e4 LT |
1044 | return 0; |
1045 | } | |
1046 | return -EPERM; | |
1047 | } | |
1048 | ||
1049 | /* | |
1050 | * Called when an inode is about to be open. | |
1051 | * We use this to disallow opening large files on 32bit systems if | |
1052 | * the caller didn't specify O_LARGEFILE. On 64bit systems we force | |
1053 | * on this flag in sys_open. | |
1054 | */ | |
1055 | int generic_file_open(struct inode * inode, struct file * filp) | |
1056 | { | |
1057 | if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS) | |
a9c62a18 | 1058 | return -EOVERFLOW; |
1da177e4 LT |
1059 | return 0; |
1060 | } | |
1061 | ||
1062 | EXPORT_SYMBOL(generic_file_open); | |
1063 | ||
1064 | /* | |
1065 | * This is used by subsystems that don't want seekable | |
06b1e104 DT |
1066 | * file descriptors. The function is not supposed to ever fail, the only |
1067 | * reason it returns an 'int' and not 'void' is so that it can be plugged | |
1068 | * directly into file_operations structure. | |
1da177e4 LT |
1069 | */ |
1070 | int nonseekable_open(struct inode *inode, struct file *filp) | |
1071 | { | |
1072 | filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE); | |
1073 | return 0; | |
1074 | } | |
1075 | ||
1076 | EXPORT_SYMBOL(nonseekable_open); |