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