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> |
1da177e4 | 10 | #include <linux/quotaops.h> |
0eeca283 | 11 | #include <linux/fsnotify.h> |
1da177e4 LT |
12 | #include <linux/module.h> |
13 | #include <linux/slab.h> | |
14 | #include <linux/tty.h> | |
15 | #include <linux/namei.h> | |
16 | #include <linux/backing-dev.h> | |
16f7e0fe | 17 | #include <linux/capability.h> |
1da177e4 LT |
18 | #include <linux/security.h> |
19 | #include <linux/mount.h> | |
20 | #include <linux/vfs.h> | |
5590ff0d | 21 | #include <linux/fcntl.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> |
1da177e4 | 30 | |
726c3342 | 31 | int vfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 LT |
32 | { |
33 | int retval = -ENODEV; | |
34 | ||
726c3342 | 35 | if (dentry) { |
1da177e4 | 36 | retval = -ENOSYS; |
726c3342 | 37 | if (dentry->d_sb->s_op->statfs) { |
1da177e4 | 38 | memset(buf, 0, sizeof(*buf)); |
726c3342 | 39 | retval = security_sb_statfs(dentry); |
1da177e4 LT |
40 | if (retval) |
41 | return retval; | |
726c3342 | 42 | retval = dentry->d_sb->s_op->statfs(dentry, buf); |
1da177e4 LT |
43 | if (retval == 0 && buf->f_frsize == 0) |
44 | buf->f_frsize = buf->f_bsize; | |
45 | } | |
46 | } | |
47 | return retval; | |
48 | } | |
49 | ||
50 | EXPORT_SYMBOL(vfs_statfs); | |
51 | ||
726c3342 | 52 | static int vfs_statfs_native(struct dentry *dentry, struct statfs *buf) |
1da177e4 LT |
53 | { |
54 | struct kstatfs st; | |
55 | int retval; | |
56 | ||
726c3342 | 57 | retval = vfs_statfs(dentry, &st); |
1da177e4 LT |
58 | if (retval) |
59 | return retval; | |
60 | ||
61 | if (sizeof(*buf) == sizeof(st)) | |
62 | memcpy(buf, &st, sizeof(st)); | |
63 | else { | |
64 | if (sizeof buf->f_blocks == 4) { | |
65 | if ((st.f_blocks | st.f_bfree | st.f_bavail) & | |
66 | 0xffffffff00000000ULL) | |
67 | return -EOVERFLOW; | |
68 | /* | |
69 | * f_files and f_ffree may be -1; it's okay to stuff | |
70 | * that into 32 bits | |
71 | */ | |
72 | if (st.f_files != -1 && | |
73 | (st.f_files & 0xffffffff00000000ULL)) | |
74 | return -EOVERFLOW; | |
75 | if (st.f_ffree != -1 && | |
76 | (st.f_ffree & 0xffffffff00000000ULL)) | |
77 | return -EOVERFLOW; | |
78 | } | |
79 | ||
80 | buf->f_type = st.f_type; | |
81 | buf->f_bsize = st.f_bsize; | |
82 | buf->f_blocks = st.f_blocks; | |
83 | buf->f_bfree = st.f_bfree; | |
84 | buf->f_bavail = st.f_bavail; | |
85 | buf->f_files = st.f_files; | |
86 | buf->f_ffree = st.f_ffree; | |
87 | buf->f_fsid = st.f_fsid; | |
88 | buf->f_namelen = st.f_namelen; | |
89 | buf->f_frsize = st.f_frsize; | |
90 | memset(buf->f_spare, 0, sizeof(buf->f_spare)); | |
91 | } | |
92 | return 0; | |
93 | } | |
94 | ||
726c3342 | 95 | static int vfs_statfs64(struct dentry *dentry, struct statfs64 *buf) |
1da177e4 LT |
96 | { |
97 | struct kstatfs st; | |
98 | int retval; | |
99 | ||
726c3342 | 100 | retval = vfs_statfs(dentry, &st); |
1da177e4 LT |
101 | if (retval) |
102 | return retval; | |
103 | ||
104 | if (sizeof(*buf) == sizeof(st)) | |
105 | memcpy(buf, &st, sizeof(st)); | |
106 | else { | |
107 | buf->f_type = st.f_type; | |
108 | buf->f_bsize = st.f_bsize; | |
109 | buf->f_blocks = st.f_blocks; | |
110 | buf->f_bfree = st.f_bfree; | |
111 | buf->f_bavail = st.f_bavail; | |
112 | buf->f_files = st.f_files; | |
113 | buf->f_ffree = st.f_ffree; | |
114 | buf->f_fsid = st.f_fsid; | |
115 | buf->f_namelen = st.f_namelen; | |
116 | buf->f_frsize = st.f_frsize; | |
117 | memset(buf->f_spare, 0, sizeof(buf->f_spare)); | |
118 | } | |
119 | return 0; | |
120 | } | |
121 | ||
122 | asmlinkage long sys_statfs(const char __user * path, struct statfs __user * buf) | |
123 | { | |
124 | struct nameidata nd; | |
125 | int error; | |
126 | ||
127 | error = user_path_walk(path, &nd); | |
128 | if (!error) { | |
129 | struct statfs tmp; | |
4ac91378 | 130 | error = vfs_statfs_native(nd.path.dentry, &tmp); |
1da177e4 LT |
131 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
132 | error = -EFAULT; | |
1d957f9b | 133 | path_put(&nd.path); |
1da177e4 LT |
134 | } |
135 | return error; | |
136 | } | |
137 | ||
138 | ||
139 | asmlinkage long sys_statfs64(const char __user *path, size_t sz, struct statfs64 __user *buf) | |
140 | { | |
141 | struct nameidata nd; | |
142 | long error; | |
143 | ||
144 | if (sz != sizeof(*buf)) | |
145 | return -EINVAL; | |
146 | error = user_path_walk(path, &nd); | |
147 | if (!error) { | |
148 | struct statfs64 tmp; | |
4ac91378 | 149 | error = vfs_statfs64(nd.path.dentry, &tmp); |
1da177e4 LT |
150 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
151 | error = -EFAULT; | |
1d957f9b | 152 | path_put(&nd.path); |
1da177e4 LT |
153 | } |
154 | return error; | |
155 | } | |
156 | ||
157 | ||
158 | asmlinkage long sys_fstatfs(unsigned int fd, struct statfs __user * buf) | |
159 | { | |
160 | struct file * file; | |
161 | struct statfs tmp; | |
162 | int error; | |
163 | ||
164 | error = -EBADF; | |
165 | file = fget(fd); | |
166 | if (!file) | |
167 | goto out; | |
0f7fc9e4 | 168 | error = vfs_statfs_native(file->f_path.dentry, &tmp); |
1da177e4 LT |
169 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
170 | error = -EFAULT; | |
171 | fput(file); | |
172 | out: | |
173 | return error; | |
174 | } | |
175 | ||
176 | asmlinkage long sys_fstatfs64(unsigned int fd, size_t sz, struct statfs64 __user *buf) | |
177 | { | |
178 | struct file * file; | |
179 | struct statfs64 tmp; | |
180 | int error; | |
181 | ||
182 | if (sz != sizeof(*buf)) | |
183 | return -EINVAL; | |
184 | ||
185 | error = -EBADF; | |
186 | file = fget(fd); | |
187 | if (!file) | |
188 | goto out; | |
0f7fc9e4 | 189 | error = vfs_statfs64(file->f_path.dentry, &tmp); |
1da177e4 LT |
190 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
191 | error = -EFAULT; | |
192 | fput(file); | |
193 | out: | |
194 | return error; | |
195 | } | |
196 | ||
4a30131e N |
197 | int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, |
198 | struct file *filp) | |
1da177e4 LT |
199 | { |
200 | int err; | |
201 | struct iattr newattrs; | |
202 | ||
203 | /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */ | |
204 | if (length < 0) | |
205 | return -EINVAL; | |
206 | ||
207 | newattrs.ia_size = length; | |
4a30131e | 208 | newattrs.ia_valid = ATTR_SIZE | time_attrs; |
cc4e69de MS |
209 | if (filp) { |
210 | newattrs.ia_file = filp; | |
211 | newattrs.ia_valid |= ATTR_FILE; | |
212 | } | |
1da177e4 | 213 | |
7b82dc0e LT |
214 | /* Remove suid/sgid on truncate too */ |
215 | newattrs.ia_valid |= should_remove_suid(dentry); | |
216 | ||
1b1dcc1b | 217 | mutex_lock(&dentry->d_inode->i_mutex); |
1da177e4 | 218 | err = notify_change(dentry, &newattrs); |
1b1dcc1b | 219 | mutex_unlock(&dentry->d_inode->i_mutex); |
1da177e4 LT |
220 | return err; |
221 | } | |
222 | ||
b01ec0ef | 223 | static long do_sys_truncate(const char __user * path, loff_t length) |
1da177e4 LT |
224 | { |
225 | struct nameidata nd; | |
226 | struct inode * inode; | |
227 | int error; | |
228 | ||
229 | error = -EINVAL; | |
230 | if (length < 0) /* sorry, but loff_t says... */ | |
231 | goto out; | |
232 | ||
233 | error = user_path_walk(path, &nd); | |
234 | if (error) | |
235 | goto out; | |
4ac91378 | 236 | inode = nd.path.dentry->d_inode; |
1da177e4 LT |
237 | |
238 | /* For directories it's -EISDIR, for other non-regulars - -EINVAL */ | |
239 | error = -EISDIR; | |
240 | if (S_ISDIR(inode->i_mode)) | |
241 | goto dput_and_out; | |
242 | ||
243 | error = -EINVAL; | |
244 | if (!S_ISREG(inode->i_mode)) | |
245 | goto dput_and_out; | |
246 | ||
e4543edd | 247 | error = vfs_permission(&nd, MAY_WRITE); |
1da177e4 LT |
248 | if (error) |
249 | goto dput_and_out; | |
250 | ||
251 | error = -EROFS; | |
252 | if (IS_RDONLY(inode)) | |
253 | goto dput_and_out; | |
254 | ||
255 | error = -EPERM; | |
256 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
257 | goto dput_and_out; | |
258 | ||
9700382c | 259 | error = get_write_access(inode); |
1da177e4 LT |
260 | if (error) |
261 | goto dput_and_out; | |
262 | ||
9700382c | 263 | /* |
264 | * Make sure that there are no leases. get_write_access() protects | |
265 | * against the truncate racing with a lease-granting setlease(). | |
266 | */ | |
267 | error = break_lease(inode, FMODE_WRITE); | |
1da177e4 | 268 | if (error) |
9700382c | 269 | goto put_write_and_out; |
1da177e4 LT |
270 | |
271 | error = locks_verify_truncate(inode, NULL, length); | |
272 | if (!error) { | |
273 | DQUOT_INIT(inode); | |
4ac91378 | 274 | error = do_truncate(nd.path.dentry, length, 0, NULL); |
1da177e4 | 275 | } |
1da177e4 | 276 | |
9700382c | 277 | put_write_and_out: |
278 | put_write_access(inode); | |
1da177e4 | 279 | dput_and_out: |
1d957f9b | 280 | path_put(&nd.path); |
1da177e4 LT |
281 | out: |
282 | return error; | |
283 | } | |
284 | ||
285 | asmlinkage long sys_truncate(const char __user * path, unsigned long length) | |
286 | { | |
287 | /* on 32-bit boxen it will cut the range 2^31--2^32-1 off */ | |
288 | return do_sys_truncate(path, (long)length); | |
289 | } | |
290 | ||
b01ec0ef | 291 | static long do_sys_ftruncate(unsigned int fd, loff_t length, int small) |
1da177e4 LT |
292 | { |
293 | struct inode * inode; | |
294 | struct dentry *dentry; | |
295 | struct file * file; | |
296 | int error; | |
297 | ||
298 | error = -EINVAL; | |
299 | if (length < 0) | |
300 | goto out; | |
301 | error = -EBADF; | |
302 | file = fget(fd); | |
303 | if (!file) | |
304 | goto out; | |
305 | ||
306 | /* explicitly opened as large or we are on 64-bit box */ | |
307 | if (file->f_flags & O_LARGEFILE) | |
308 | small = 0; | |
309 | ||
0f7fc9e4 | 310 | dentry = file->f_path.dentry; |
1da177e4 LT |
311 | inode = dentry->d_inode; |
312 | error = -EINVAL; | |
313 | if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE)) | |
314 | goto out_putf; | |
315 | ||
316 | error = -EINVAL; | |
317 | /* Cannot ftruncate over 2^31 bytes without large file support */ | |
318 | if (small && length > MAX_NON_LFS) | |
319 | goto out_putf; | |
320 | ||
321 | error = -EPERM; | |
322 | if (IS_APPEND(inode)) | |
323 | goto out_putf; | |
324 | ||
325 | error = locks_verify_truncate(inode, file, length); | |
326 | if (!error) | |
6e656be8 | 327 | error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file); |
1da177e4 LT |
328 | out_putf: |
329 | fput(file); | |
330 | out: | |
331 | return error; | |
332 | } | |
333 | ||
334 | asmlinkage long sys_ftruncate(unsigned int fd, unsigned long length) | |
335 | { | |
0a489cb3 | 336 | long ret = do_sys_ftruncate(fd, length, 1); |
385910f2 | 337 | /* avoid REGPARM breakage on x86: */ |
0a489cb3 LT |
338 | prevent_tail_call(ret); |
339 | return ret; | |
1da177e4 LT |
340 | } |
341 | ||
342 | /* LFS versions of truncate are only needed on 32 bit machines */ | |
343 | #if BITS_PER_LONG == 32 | |
344 | asmlinkage long sys_truncate64(const char __user * path, loff_t length) | |
345 | { | |
346 | return do_sys_truncate(path, length); | |
347 | } | |
348 | ||
349 | asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length) | |
350 | { | |
0a489cb3 | 351 | long ret = do_sys_ftruncate(fd, length, 0); |
385910f2 | 352 | /* avoid REGPARM breakage on x86: */ |
0a489cb3 LT |
353 | prevent_tail_call(ret); |
354 | return ret; | |
1da177e4 LT |
355 | } |
356 | #endif | |
357 | ||
97ac7350 AA |
358 | asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len) |
359 | { | |
360 | struct file *file; | |
361 | struct inode *inode; | |
362 | long ret = -EINVAL; | |
363 | ||
364 | if (offset < 0 || len <= 0) | |
365 | goto out; | |
366 | ||
367 | /* Return error if mode is not supported */ | |
368 | ret = -EOPNOTSUPP; | |
369 | if (mode && !(mode & FALLOC_FL_KEEP_SIZE)) | |
370 | goto out; | |
371 | ||
372 | ret = -EBADF; | |
373 | file = fget(fd); | |
374 | if (!file) | |
375 | goto out; | |
376 | if (!(file->f_mode & FMODE_WRITE)) | |
377 | goto out_fput; | |
378 | /* | |
379 | * Revalidate the write permissions, in case security policy has | |
380 | * changed since the files were opened. | |
381 | */ | |
382 | ret = security_file_permission(file, MAY_WRITE); | |
383 | if (ret) | |
384 | goto out_fput; | |
385 | ||
386 | inode = file->f_path.dentry->d_inode; | |
387 | ||
388 | ret = -ESPIPE; | |
389 | if (S_ISFIFO(inode->i_mode)) | |
390 | goto out_fput; | |
391 | ||
392 | ret = -ENODEV; | |
393 | /* | |
394 | * Let individual file system decide if it supports preallocation | |
395 | * for directories or not. | |
396 | */ | |
397 | if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) | |
398 | goto out_fput; | |
399 | ||
400 | ret = -EFBIG; | |
401 | /* Check for wrap through zero too */ | |
402 | if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0)) | |
403 | goto out_fput; | |
404 | ||
405 | if (inode->i_op && inode->i_op->fallocate) | |
406 | ret = inode->i_op->fallocate(inode, mode, offset, len); | |
407 | else | |
0d786d4a | 408 | ret = -EOPNOTSUPP; |
97ac7350 AA |
409 | |
410 | out_fput: | |
411 | fput(file); | |
412 | out: | |
413 | return ret; | |
414 | } | |
415 | ||
1da177e4 LT |
416 | /* |
417 | * access() needs to use the real uid/gid, not the effective uid/gid. | |
418 | * We do this by temporarily clearing all FS-related capabilities and | |
419 | * switching the fsuid/fsgid around to the real ones. | |
420 | */ | |
5590ff0d | 421 | asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode) |
1da177e4 LT |
422 | { |
423 | struct nameidata nd; | |
424 | int old_fsuid, old_fsgid; | |
425 | kernel_cap_t old_cap; | |
426 | int res; | |
427 | ||
428 | if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */ | |
429 | return -EINVAL; | |
430 | ||
431 | old_fsuid = current->fsuid; | |
432 | old_fsgid = current->fsgid; | |
433 | old_cap = current->cap_effective; | |
434 | ||
435 | current->fsuid = current->uid; | |
436 | current->fsgid = current->gid; | |
437 | ||
438 | /* | |
439 | * Clear the capabilities if we switch to a non-root user | |
440 | * | |
441 | * FIXME: There is a race here against sys_capset. The | |
442 | * capabilities can change yet we will restore the old | |
443 | * value below. We should hold task_capabilities_lock, | |
444 | * but we cannot because user_path_walk can sleep. | |
445 | */ | |
446 | if (current->uid) | |
447 | cap_clear(current->cap_effective); | |
448 | else | |
449 | current->cap_effective = current->cap_permitted; | |
450 | ||
5590ff0d | 451 | res = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd); |
6902d925 DH |
452 | if (res) |
453 | goto out; | |
454 | ||
455 | res = vfs_permission(&nd, mode); | |
456 | /* SuS v2 requires we report a read only fs too */ | |
457 | if(res || !(mode & S_IWOTH) || | |
4ac91378 | 458 | special_file(nd.path.dentry->d_inode->i_mode)) |
6902d925 DH |
459 | goto out_path_release; |
460 | ||
4ac91378 | 461 | if(IS_RDONLY(nd.path.dentry->d_inode)) |
6902d925 | 462 | res = -EROFS; |
1da177e4 | 463 | |
6902d925 | 464 | out_path_release: |
1d957f9b | 465 | path_put(&nd.path); |
6902d925 | 466 | out: |
1da177e4 LT |
467 | current->fsuid = old_fsuid; |
468 | current->fsgid = old_fsgid; | |
469 | current->cap_effective = old_cap; | |
470 | ||
471 | return res; | |
472 | } | |
473 | ||
5590ff0d UD |
474 | asmlinkage long sys_access(const char __user *filename, int mode) |
475 | { | |
476 | return sys_faccessat(AT_FDCWD, filename, mode); | |
477 | } | |
478 | ||
1da177e4 LT |
479 | asmlinkage long sys_chdir(const char __user * filename) |
480 | { | |
481 | struct nameidata nd; | |
482 | int error; | |
483 | ||
650a8983 MS |
484 | error = __user_walk(filename, |
485 | LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_CHDIR, &nd); | |
1da177e4 LT |
486 | if (error) |
487 | goto out; | |
488 | ||
e4543edd | 489 | error = vfs_permission(&nd, MAY_EXEC); |
1da177e4 LT |
490 | if (error) |
491 | goto dput_and_out; | |
492 | ||
ac748a09 | 493 | set_fs_pwd(current->fs, &nd.path); |
1da177e4 LT |
494 | |
495 | dput_and_out: | |
1d957f9b | 496 | path_put(&nd.path); |
1da177e4 LT |
497 | out: |
498 | return error; | |
499 | } | |
500 | ||
501 | asmlinkage long sys_fchdir(unsigned int fd) | |
502 | { | |
503 | struct file *file; | |
1da177e4 | 504 | struct inode *inode; |
1da177e4 LT |
505 | int error; |
506 | ||
507 | error = -EBADF; | |
508 | file = fget(fd); | |
509 | if (!file) | |
510 | goto out; | |
511 | ||
ac748a09 | 512 | inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
513 | |
514 | error = -ENOTDIR; | |
515 | if (!S_ISDIR(inode->i_mode)) | |
516 | goto out_putf; | |
517 | ||
8c744fb8 | 518 | error = file_permission(file, MAY_EXEC); |
1da177e4 | 519 | if (!error) |
ac748a09 | 520 | set_fs_pwd(current->fs, &file->f_path); |
1da177e4 LT |
521 | out_putf: |
522 | fput(file); | |
523 | out: | |
524 | return error; | |
525 | } | |
526 | ||
527 | asmlinkage long sys_chroot(const char __user * filename) | |
528 | { | |
529 | struct nameidata nd; | |
530 | int error; | |
531 | ||
532 | error = __user_walk(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY | LOOKUP_NOALT, &nd); | |
533 | if (error) | |
534 | goto out; | |
535 | ||
e4543edd | 536 | error = vfs_permission(&nd, MAY_EXEC); |
1da177e4 LT |
537 | if (error) |
538 | goto dput_and_out; | |
539 | ||
540 | error = -EPERM; | |
541 | if (!capable(CAP_SYS_CHROOT)) | |
542 | goto dput_and_out; | |
543 | ||
ac748a09 | 544 | set_fs_root(current->fs, &nd.path); |
1da177e4 LT |
545 | set_fs_altroot(); |
546 | error = 0; | |
547 | dput_and_out: | |
1d957f9b | 548 | path_put(&nd.path); |
1da177e4 LT |
549 | out: |
550 | return error; | |
551 | } | |
552 | ||
553 | asmlinkage long sys_fchmod(unsigned int fd, mode_t mode) | |
554 | { | |
555 | struct inode * inode; | |
556 | struct dentry * dentry; | |
557 | struct file * file; | |
558 | int err = -EBADF; | |
559 | struct iattr newattrs; | |
560 | ||
561 | file = fget(fd); | |
562 | if (!file) | |
563 | goto out; | |
564 | ||
0f7fc9e4 | 565 | dentry = file->f_path.dentry; |
1da177e4 LT |
566 | inode = dentry->d_inode; |
567 | ||
5a190ae6 | 568 | audit_inode(NULL, dentry); |
73241ccc | 569 | |
1da177e4 LT |
570 | err = -EROFS; |
571 | if (IS_RDONLY(inode)) | |
572 | goto out_putf; | |
573 | err = -EPERM; | |
574 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
575 | goto out_putf; | |
1b1dcc1b | 576 | mutex_lock(&inode->i_mutex); |
1da177e4 LT |
577 | if (mode == (mode_t) -1) |
578 | mode = inode->i_mode; | |
579 | newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); | |
580 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; | |
581 | err = notify_change(dentry, &newattrs); | |
1b1dcc1b | 582 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
583 | |
584 | out_putf: | |
585 | fput(file); | |
586 | out: | |
587 | return err; | |
588 | } | |
589 | ||
5590ff0d UD |
590 | asmlinkage long sys_fchmodat(int dfd, const char __user *filename, |
591 | mode_t mode) | |
1da177e4 LT |
592 | { |
593 | struct nameidata nd; | |
594 | struct inode * inode; | |
595 | int error; | |
596 | struct iattr newattrs; | |
597 | ||
5590ff0d | 598 | error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd); |
1da177e4 LT |
599 | if (error) |
600 | goto out; | |
4ac91378 | 601 | inode = nd.path.dentry->d_inode; |
1da177e4 LT |
602 | |
603 | error = -EROFS; | |
604 | if (IS_RDONLY(inode)) | |
605 | goto dput_and_out; | |
606 | ||
607 | error = -EPERM; | |
608 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
609 | goto dput_and_out; | |
610 | ||
1b1dcc1b | 611 | mutex_lock(&inode->i_mutex); |
1da177e4 LT |
612 | if (mode == (mode_t) -1) |
613 | mode = inode->i_mode; | |
614 | newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); | |
615 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; | |
4ac91378 | 616 | error = notify_change(nd.path.dentry, &newattrs); |
1b1dcc1b | 617 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
618 | |
619 | dput_and_out: | |
1d957f9b | 620 | path_put(&nd.path); |
1da177e4 LT |
621 | out: |
622 | return error; | |
623 | } | |
624 | ||
5590ff0d UD |
625 | asmlinkage long sys_chmod(const char __user *filename, mode_t mode) |
626 | { | |
627 | return sys_fchmodat(AT_FDCWD, filename, mode); | |
628 | } | |
629 | ||
1da177e4 LT |
630 | static int chown_common(struct dentry * dentry, uid_t user, gid_t group) |
631 | { | |
632 | struct inode * inode; | |
633 | int error; | |
634 | struct iattr newattrs; | |
635 | ||
636 | error = -ENOENT; | |
637 | if (!(inode = dentry->d_inode)) { | |
638 | printk(KERN_ERR "chown_common: NULL inode\n"); | |
639 | goto out; | |
640 | } | |
641 | error = -EROFS; | |
642 | if (IS_RDONLY(inode)) | |
643 | goto out; | |
644 | error = -EPERM; | |
645 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
646 | goto out; | |
647 | newattrs.ia_valid = ATTR_CTIME; | |
648 | if (user != (uid_t) -1) { | |
649 | newattrs.ia_valid |= ATTR_UID; | |
650 | newattrs.ia_uid = user; | |
651 | } | |
652 | if (group != (gid_t) -1) { | |
653 | newattrs.ia_valid |= ATTR_GID; | |
654 | newattrs.ia_gid = group; | |
655 | } | |
656 | if (!S_ISDIR(inode->i_mode)) | |
b5376771 SH |
657 | newattrs.ia_valid |= |
658 | ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV; | |
1b1dcc1b | 659 | mutex_lock(&inode->i_mutex); |
1da177e4 | 660 | error = notify_change(dentry, &newattrs); |
1b1dcc1b | 661 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
662 | out: |
663 | return error; | |
664 | } | |
665 | ||
666 | asmlinkage long sys_chown(const char __user * filename, uid_t user, gid_t group) | |
667 | { | |
668 | struct nameidata nd; | |
669 | int error; | |
670 | ||
671 | error = user_path_walk(filename, &nd); | |
6902d925 DH |
672 | if (error) |
673 | goto out; | |
4ac91378 | 674 | error = chown_common(nd.path.dentry, user, group); |
1d957f9b | 675 | path_put(&nd.path); |
6902d925 | 676 | out: |
1da177e4 LT |
677 | return error; |
678 | } | |
679 | ||
5590ff0d UD |
680 | asmlinkage long sys_fchownat(int dfd, const char __user *filename, uid_t user, |
681 | gid_t group, int flag) | |
682 | { | |
683 | struct nameidata nd; | |
684 | int error = -EINVAL; | |
685 | int follow; | |
686 | ||
687 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
688 | goto out; | |
689 | ||
690 | follow = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; | |
691 | error = __user_walk_fd(dfd, filename, follow, &nd); | |
6902d925 DH |
692 | if (error) |
693 | goto out; | |
4ac91378 | 694 | error = chown_common(nd.path.dentry, user, group); |
1d957f9b | 695 | path_put(&nd.path); |
5590ff0d UD |
696 | out: |
697 | return error; | |
698 | } | |
699 | ||
1da177e4 LT |
700 | asmlinkage long sys_lchown(const char __user * filename, uid_t user, gid_t group) |
701 | { | |
702 | struct nameidata nd; | |
703 | int error; | |
704 | ||
705 | error = user_path_walk_link(filename, &nd); | |
6902d925 DH |
706 | if (error) |
707 | goto out; | |
4ac91378 | 708 | error = chown_common(nd.path.dentry, user, group); |
1d957f9b | 709 | path_put(&nd.path); |
6902d925 | 710 | out: |
1da177e4 LT |
711 | return error; |
712 | } | |
713 | ||
714 | ||
715 | asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group) | |
716 | { | |
717 | struct file * file; | |
718 | int error = -EBADF; | |
6902d925 | 719 | struct dentry * dentry; |
1da177e4 LT |
720 | |
721 | file = fget(fd); | |
6902d925 DH |
722 | if (!file) |
723 | goto out; | |
724 | ||
0f7fc9e4 | 725 | dentry = file->f_path.dentry; |
5a190ae6 | 726 | audit_inode(NULL, dentry); |
6902d925 DH |
727 | error = chown_common(dentry, user, group); |
728 | fput(file); | |
729 | out: | |
1da177e4 LT |
730 | return error; |
731 | } | |
732 | ||
a1a5b3d9 | 733 | static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, |
834f2a4a TM |
734 | int flags, struct file *f, |
735 | int (*open)(struct inode *, struct file *)) | |
1da177e4 | 736 | { |
1da177e4 LT |
737 | struct inode *inode; |
738 | int error; | |
739 | ||
1da177e4 | 740 | f->f_flags = flags; |
a1a5b3d9 PS |
741 | f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK | |
742 | FMODE_PREAD | FMODE_PWRITE; | |
1da177e4 LT |
743 | inode = dentry->d_inode; |
744 | if (f->f_mode & FMODE_WRITE) { | |
745 | error = get_write_access(inode); | |
746 | if (error) | |
747 | goto cleanup_file; | |
748 | } | |
749 | ||
750 | f->f_mapping = inode->i_mapping; | |
0f7fc9e4 JJS |
751 | f->f_path.dentry = dentry; |
752 | f->f_path.mnt = mnt; | |
1da177e4 LT |
753 | f->f_pos = 0; |
754 | f->f_op = fops_get(inode->i_fop); | |
755 | file_move(f, &inode->i_sb->s_files); | |
756 | ||
788e7dd4 YN |
757 | error = security_dentry_open(f); |
758 | if (error) | |
759 | goto cleanup_all; | |
760 | ||
834f2a4a TM |
761 | if (!open && f->f_op) |
762 | open = f->f_op->open; | |
763 | if (open) { | |
764 | error = open(inode, f); | |
1da177e4 LT |
765 | if (error) |
766 | goto cleanup_all; | |
767 | } | |
834f2a4a | 768 | |
1da177e4 LT |
769 | f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); |
770 | ||
771 | file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); | |
772 | ||
773 | /* NB: we're sure to have correct a_ops only after f_op->open */ | |
774 | if (f->f_flags & O_DIRECT) { | |
ceffc078 CO |
775 | if (!f->f_mapping->a_ops || |
776 | ((!f->f_mapping->a_ops->direct_IO) && | |
777 | (!f->f_mapping->a_ops->get_xip_page))) { | |
1da177e4 LT |
778 | fput(f); |
779 | f = ERR_PTR(-EINVAL); | |
780 | } | |
781 | } | |
782 | ||
783 | return f; | |
784 | ||
785 | cleanup_all: | |
786 | fops_put(f->f_op); | |
787 | if (f->f_mode & FMODE_WRITE) | |
788 | put_write_access(inode); | |
789 | file_kill(f); | |
0f7fc9e4 JJS |
790 | f->f_path.dentry = NULL; |
791 | f->f_path.mnt = NULL; | |
1da177e4 LT |
792 | cleanup_file: |
793 | put_filp(f); | |
1da177e4 LT |
794 | dput(dentry); |
795 | mntput(mnt); | |
796 | return ERR_PTR(error); | |
797 | } | |
798 | ||
a1a5b3d9 PS |
799 | /* |
800 | * Note that while the flag value (low two bits) for sys_open means: | |
801 | * 00 - read-only | |
802 | * 01 - write-only | |
803 | * 10 - read-write | |
804 | * 11 - special | |
805 | * it is changed into | |
806 | * 00 - no permissions needed | |
807 | * 01 - read-permission | |
808 | * 10 - write-permission | |
809 | * 11 - read-write | |
810 | * for the internal routines (ie open_namei()/follow_link() etc). 00 is | |
811 | * used by symlinks. | |
812 | */ | |
5590ff0d UD |
813 | static struct file *do_filp_open(int dfd, const char *filename, int flags, |
814 | int mode) | |
a1a5b3d9 PS |
815 | { |
816 | int namei_flags, error; | |
817 | struct nameidata nd; | |
a1a5b3d9 PS |
818 | |
819 | namei_flags = flags; | |
820 | if ((namei_flags+1) & O_ACCMODE) | |
821 | namei_flags++; | |
a1a5b3d9 | 822 | |
5590ff0d | 823 | error = open_namei(dfd, filename, namei_flags, mode, &nd); |
a1a5b3d9 | 824 | if (!error) |
834f2a4a | 825 | return nameidata_to_filp(&nd, flags); |
a1a5b3d9 | 826 | |
a1a5b3d9 PS |
827 | return ERR_PTR(error); |
828 | } | |
5590ff0d UD |
829 | |
830 | struct file *filp_open(const char *filename, int flags, int mode) | |
831 | { | |
832 | return do_filp_open(AT_FDCWD, filename, flags, mode); | |
833 | } | |
a1a5b3d9 PS |
834 | EXPORT_SYMBOL(filp_open); |
835 | ||
834f2a4a TM |
836 | /** |
837 | * lookup_instantiate_filp - instantiates the open intent filp | |
838 | * @nd: pointer to nameidata | |
839 | * @dentry: pointer to dentry | |
840 | * @open: open callback | |
841 | * | |
842 | * Helper for filesystems that want to use lookup open intents and pass back | |
843 | * a fully instantiated struct file to the caller. | |
844 | * This function is meant to be called from within a filesystem's | |
845 | * lookup method. | |
9a56c213 OD |
846 | * Beware of calling it for non-regular files! Those ->open methods might block |
847 | * (e.g. in fifo_open), leaving you with parent locked (and in case of fifo, | |
848 | * leading to a deadlock, as nobody can open that fifo anymore, because | |
849 | * another process to open fifo will block on locked parent when doing lookup). | |
834f2a4a TM |
850 | * Note that in case of error, nd->intent.open.file is destroyed, but the |
851 | * path information remains valid. | |
852 | * If the open callback is set to NULL, then the standard f_op->open() | |
853 | * filesystem callback is substituted. | |
854 | */ | |
855 | struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry, | |
856 | int (*open)(struct inode *, struct file *)) | |
857 | { | |
858 | if (IS_ERR(nd->intent.open.file)) | |
859 | goto out; | |
860 | if (IS_ERR(dentry)) | |
861 | goto out_err; | |
4ac91378 | 862 | nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->path.mnt), |
834f2a4a TM |
863 | nd->intent.open.flags - 1, |
864 | nd->intent.open.file, | |
865 | open); | |
866 | out: | |
867 | return nd->intent.open.file; | |
868 | out_err: | |
869 | release_open_intent(nd); | |
870 | nd->intent.open.file = (struct file *)dentry; | |
871 | goto out; | |
872 | } | |
873 | EXPORT_SYMBOL_GPL(lookup_instantiate_filp); | |
874 | ||
875 | /** | |
876 | * nameidata_to_filp - convert a nameidata to an open filp. | |
877 | * @nd: pointer to nameidata | |
878 | * @flags: open flags | |
879 | * | |
880 | * Note that this function destroys the original nameidata | |
881 | */ | |
882 | struct file *nameidata_to_filp(struct nameidata *nd, int flags) | |
883 | { | |
884 | struct file *filp; | |
885 | ||
886 | /* Pick up the filp from the open intent */ | |
887 | filp = nd->intent.open.file; | |
888 | /* Has the filesystem initialised the file for us? */ | |
0f7fc9e4 | 889 | if (filp->f_path.dentry == NULL) |
4ac91378 JB |
890 | filp = __dentry_open(nd->path.dentry, nd->path.mnt, flags, filp, |
891 | NULL); | |
834f2a4a | 892 | else |
1d957f9b | 893 | path_put(&nd->path); |
834f2a4a TM |
894 | return filp; |
895 | } | |
896 | ||
6fdcc216 PS |
897 | /* |
898 | * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an | |
899 | * error. | |
900 | */ | |
a1a5b3d9 PS |
901 | struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) |
902 | { | |
903 | int error; | |
904 | struct file *f; | |
905 | ||
906 | error = -ENFILE; | |
907 | f = get_empty_filp(); | |
6fdcc216 PS |
908 | if (f == NULL) { |
909 | dput(dentry); | |
910 | mntput(mnt); | |
a1a5b3d9 | 911 | return ERR_PTR(error); |
6fdcc216 | 912 | } |
a1a5b3d9 | 913 | |
834f2a4a | 914 | return __dentry_open(dentry, mnt, flags, f, NULL); |
a1a5b3d9 | 915 | } |
1da177e4 LT |
916 | EXPORT_SYMBOL(dentry_open); |
917 | ||
918 | /* | |
919 | * Find an empty file descriptor entry, and mark it busy. | |
920 | */ | |
4a19542e | 921 | int get_unused_fd_flags(int flags) |
1da177e4 LT |
922 | { |
923 | struct files_struct * files = current->files; | |
924 | int fd, error; | |
badf1662 | 925 | struct fdtable *fdt; |
1da177e4 LT |
926 | |
927 | error = -EMFILE; | |
928 | spin_lock(&files->file_lock); | |
929 | ||
930 | repeat: | |
badf1662 | 931 | fdt = files_fdtable(files); |
bbea9f69 | 932 | fd = find_next_zero_bit(fdt->open_fds->fds_bits, fdt->max_fds, |
0c9e63fd | 933 | files->next_fd); |
1da177e4 LT |
934 | |
935 | /* | |
936 | * N.B. For clone tasks sharing a files structure, this test | |
937 | * will limit the total number of files that can be opened. | |
938 | */ | |
939 | if (fd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | |
940 | goto out; | |
941 | ||
942 | /* Do we need to expand the fd array or fd set? */ | |
943 | error = expand_files(files, fd); | |
944 | if (error < 0) | |
945 | goto out; | |
946 | ||
947 | if (error) { | |
948 | /* | |
949 | * If we needed to expand the fs array we | |
950 | * might have blocked - try again. | |
951 | */ | |
952 | error = -EMFILE; | |
953 | goto repeat; | |
954 | } | |
955 | ||
badf1662 | 956 | FD_SET(fd, fdt->open_fds); |
f23513e8 UD |
957 | if (flags & O_CLOEXEC) |
958 | FD_SET(fd, fdt->close_on_exec); | |
959 | else | |
960 | FD_CLR(fd, fdt->close_on_exec); | |
0c9e63fd | 961 | files->next_fd = fd + 1; |
1da177e4 LT |
962 | #if 1 |
963 | /* Sanity check */ | |
badf1662 | 964 | if (fdt->fd[fd] != NULL) { |
1da177e4 | 965 | printk(KERN_WARNING "get_unused_fd: slot %d not NULL!\n", fd); |
badf1662 | 966 | fdt->fd[fd] = NULL; |
1da177e4 LT |
967 | } |
968 | #endif | |
969 | error = fd; | |
970 | ||
971 | out: | |
972 | spin_unlock(&files->file_lock); | |
973 | return error; | |
974 | } | |
975 | ||
f23513e8 UD |
976 | int get_unused_fd(void) |
977 | { | |
978 | return get_unused_fd_flags(0); | |
979 | } | |
980 | ||
1da177e4 LT |
981 | EXPORT_SYMBOL(get_unused_fd); |
982 | ||
b01ec0ef | 983 | static void __put_unused_fd(struct files_struct *files, unsigned int fd) |
1da177e4 | 984 | { |
badf1662 DS |
985 | struct fdtable *fdt = files_fdtable(files); |
986 | __FD_CLR(fd, fdt->open_fds); | |
0c9e63fd ED |
987 | if (fd < files->next_fd) |
988 | files->next_fd = fd; | |
1da177e4 LT |
989 | } |
990 | ||
fc9b52cd | 991 | void put_unused_fd(unsigned int fd) |
1da177e4 LT |
992 | { |
993 | struct files_struct *files = current->files; | |
994 | spin_lock(&files->file_lock); | |
995 | __put_unused_fd(files, fd); | |
996 | spin_unlock(&files->file_lock); | |
997 | } | |
998 | ||
999 | EXPORT_SYMBOL(put_unused_fd); | |
1000 | ||
1001 | /* | |
5590ff0d | 1002 | * Install a file pointer in the fd array. |
1da177e4 LT |
1003 | * |
1004 | * The VFS is full of places where we drop the files lock between | |
1005 | * setting the open_fds bitmap and installing the file in the file | |
1006 | * array. At any such point, we are vulnerable to a dup2() race | |
1007 | * installing a file in the array before us. We need to detect this and | |
1008 | * fput() the struct file we are about to overwrite in this case. | |
1009 | * | |
1010 | * It should never happen - if we allow dup2() do it, _really_ bad things | |
1011 | * will follow. | |
1012 | */ | |
1013 | ||
fc9b52cd | 1014 | void fd_install(unsigned int fd, struct file *file) |
1da177e4 LT |
1015 | { |
1016 | struct files_struct *files = current->files; | |
badf1662 | 1017 | struct fdtable *fdt; |
1da177e4 | 1018 | spin_lock(&files->file_lock); |
badf1662 | 1019 | fdt = files_fdtable(files); |
ab2af1f5 DS |
1020 | BUG_ON(fdt->fd[fd] != NULL); |
1021 | rcu_assign_pointer(fdt->fd[fd], file); | |
1da177e4 LT |
1022 | spin_unlock(&files->file_lock); |
1023 | } | |
1024 | ||
1025 | EXPORT_SYMBOL(fd_install); | |
1026 | ||
5590ff0d | 1027 | long do_sys_open(int dfd, const char __user *filename, int flags, int mode) |
1da177e4 | 1028 | { |
e922efc3 MS |
1029 | char *tmp = getname(filename); |
1030 | int fd = PTR_ERR(tmp); | |
1da177e4 | 1031 | |
1da177e4 | 1032 | if (!IS_ERR(tmp)) { |
f23513e8 | 1033 | fd = get_unused_fd_flags(flags); |
1da177e4 | 1034 | if (fd >= 0) { |
5590ff0d | 1035 | struct file *f = do_filp_open(dfd, tmp, flags, mode); |
fed2fc18 TN |
1036 | if (IS_ERR(f)) { |
1037 | put_unused_fd(fd); | |
1038 | fd = PTR_ERR(f); | |
1039 | } else { | |
0f7fc9e4 | 1040 | fsnotify_open(f->f_path.dentry); |
fed2fc18 TN |
1041 | fd_install(fd, f); |
1042 | } | |
1da177e4 | 1043 | } |
1da177e4 LT |
1044 | putname(tmp); |
1045 | } | |
1046 | return fd; | |
1da177e4 | 1047 | } |
e922efc3 MS |
1048 | |
1049 | asmlinkage long sys_open(const char __user *filename, int flags, int mode) | |
1050 | { | |
385910f2 LT |
1051 | long ret; |
1052 | ||
e922efc3 MS |
1053 | if (force_o_largefile()) |
1054 | flags |= O_LARGEFILE; | |
1055 | ||
385910f2 LT |
1056 | ret = do_sys_open(AT_FDCWD, filename, flags, mode); |
1057 | /* avoid REGPARM breakage on x86: */ | |
1058 | prevent_tail_call(ret); | |
1059 | return ret; | |
e922efc3 | 1060 | } |
1da177e4 | 1061 | |
5590ff0d UD |
1062 | asmlinkage long sys_openat(int dfd, const char __user *filename, int flags, |
1063 | int mode) | |
1064 | { | |
385910f2 LT |
1065 | long ret; |
1066 | ||
5590ff0d UD |
1067 | if (force_o_largefile()) |
1068 | flags |= O_LARGEFILE; | |
1069 | ||
385910f2 LT |
1070 | ret = do_sys_open(dfd, filename, flags, mode); |
1071 | /* avoid REGPARM breakage on x86: */ | |
1072 | prevent_tail_call(ret); | |
1073 | return ret; | |
5590ff0d | 1074 | } |
5590ff0d | 1075 | |
1da177e4 LT |
1076 | #ifndef __alpha__ |
1077 | ||
1078 | /* | |
1079 | * For backward compatibility? Maybe this should be moved | |
1080 | * into arch/i386 instead? | |
1081 | */ | |
1082 | asmlinkage long sys_creat(const char __user * pathname, int mode) | |
1083 | { | |
1084 | return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode); | |
1085 | } | |
1086 | ||
1087 | #endif | |
1088 | ||
1089 | /* | |
1090 | * "id" is the POSIX thread ID. We use the | |
1091 | * files pointer for this.. | |
1092 | */ | |
1093 | int filp_close(struct file *filp, fl_owner_t id) | |
1094 | { | |
45778ca8 | 1095 | int retval = 0; |
1da177e4 LT |
1096 | |
1097 | if (!file_count(filp)) { | |
1098 | printk(KERN_ERR "VFS: Close: file count is 0\n"); | |
45778ca8 | 1099 | return 0; |
1da177e4 LT |
1100 | } |
1101 | ||
45778ca8 | 1102 | if (filp->f_op && filp->f_op->flush) |
75e1fcc0 | 1103 | retval = filp->f_op->flush(filp, id); |
1da177e4 LT |
1104 | |
1105 | dnotify_flush(filp, id); | |
1106 | locks_remove_posix(filp, id); | |
1107 | fput(filp); | |
1108 | return retval; | |
1109 | } | |
1110 | ||
1111 | EXPORT_SYMBOL(filp_close); | |
1112 | ||
1113 | /* | |
1114 | * Careful here! We test whether the file pointer is NULL before | |
1115 | * releasing the fd. This ensures that one clone task can't release | |
1116 | * an fd while another clone is opening it. | |
1117 | */ | |
1118 | asmlinkage long sys_close(unsigned int fd) | |
1119 | { | |
1120 | struct file * filp; | |
1121 | struct files_struct *files = current->files; | |
badf1662 | 1122 | struct fdtable *fdt; |
ee731f4f | 1123 | int retval; |
1da177e4 LT |
1124 | |
1125 | spin_lock(&files->file_lock); | |
badf1662 DS |
1126 | fdt = files_fdtable(files); |
1127 | if (fd >= fdt->max_fds) | |
1da177e4 | 1128 | goto out_unlock; |
badf1662 | 1129 | filp = fdt->fd[fd]; |
1da177e4 LT |
1130 | if (!filp) |
1131 | goto out_unlock; | |
ab2af1f5 | 1132 | rcu_assign_pointer(fdt->fd[fd], NULL); |
badf1662 | 1133 | FD_CLR(fd, fdt->close_on_exec); |
1da177e4 LT |
1134 | __put_unused_fd(files, fd); |
1135 | spin_unlock(&files->file_lock); | |
ee731f4f EP |
1136 | retval = filp_close(filp, files); |
1137 | ||
1138 | /* can't restart close syscall because file table entry was cleared */ | |
1139 | if (unlikely(retval == -ERESTARTSYS || | |
1140 | retval == -ERESTARTNOINTR || | |
1141 | retval == -ERESTARTNOHAND || | |
1142 | retval == -ERESTART_RESTARTBLOCK)) | |
1143 | retval = -EINTR; | |
1144 | ||
1145 | return retval; | |
1da177e4 LT |
1146 | |
1147 | out_unlock: | |
1148 | spin_unlock(&files->file_lock); | |
1149 | return -EBADF; | |
1150 | } | |
1151 | ||
1152 | EXPORT_SYMBOL(sys_close); | |
1153 | ||
1154 | /* | |
1155 | * This routine simulates a hangup on the tty, to arrange that users | |
1156 | * are given clean terminals at login time. | |
1157 | */ | |
1158 | asmlinkage long sys_vhangup(void) | |
1159 | { | |
1160 | if (capable(CAP_SYS_TTY_CONFIG)) { | |
24ec839c | 1161 | /* XXX: this needs locking */ |
1da177e4 LT |
1162 | tty_vhangup(current->signal->tty); |
1163 | return 0; | |
1164 | } | |
1165 | return -EPERM; | |
1166 | } | |
1167 | ||
1168 | /* | |
1169 | * Called when an inode is about to be open. | |
1170 | * We use this to disallow opening large files on 32bit systems if | |
1171 | * the caller didn't specify O_LARGEFILE. On 64bit systems we force | |
1172 | * on this flag in sys_open. | |
1173 | */ | |
1174 | int generic_file_open(struct inode * inode, struct file * filp) | |
1175 | { | |
1176 | if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS) | |
a9c62a18 | 1177 | return -EOVERFLOW; |
1da177e4 LT |
1178 | return 0; |
1179 | } | |
1180 | ||
1181 | EXPORT_SYMBOL(generic_file_open); | |
1182 | ||
1183 | /* | |
1184 | * This is used by subsystems that don't want seekable | |
1185 | * file descriptors | |
1186 | */ | |
1187 | int nonseekable_open(struct inode *inode, struct file *filp) | |
1188 | { | |
1189 | filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE); | |
1190 | return 0; | |
1191 | } | |
1192 | ||
1193 | EXPORT_SYMBOL(nonseekable_open); |