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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> |
1da177e4 | 11 | #include <linux/quotaops.h> |
0eeca283 | 12 | #include <linux/fsnotify.h> |
1da177e4 LT |
13 | #include <linux/module.h> |
14 | #include <linux/slab.h> | |
15 | #include <linux/tty.h> | |
16 | #include <linux/namei.h> | |
17 | #include <linux/backing-dev.h> | |
16f7e0fe | 18 | #include <linux/capability.h> |
1da177e4 LT |
19 | #include <linux/security.h> |
20 | #include <linux/mount.h> | |
21 | #include <linux/vfs.h> | |
5590ff0d | 22 | #include <linux/fcntl.h> |
1da177e4 LT |
23 | #include <asm/uaccess.h> |
24 | #include <linux/fs.h> | |
ef3daeda | 25 | #include <linux/personality.h> |
1da177e4 LT |
26 | #include <linux/pagemap.h> |
27 | #include <linux/syscalls.h> | |
ab2af1f5 | 28 | #include <linux/rcupdate.h> |
73241ccc | 29 | #include <linux/audit.h> |
97ac7350 | 30 | #include <linux/falloc.h> |
1da177e4 | 31 | |
726c3342 | 32 | int vfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 LT |
33 | { |
34 | int retval = -ENODEV; | |
35 | ||
726c3342 | 36 | if (dentry) { |
1da177e4 | 37 | retval = -ENOSYS; |
726c3342 | 38 | if (dentry->d_sb->s_op->statfs) { |
1da177e4 | 39 | memset(buf, 0, sizeof(*buf)); |
726c3342 | 40 | retval = security_sb_statfs(dentry); |
1da177e4 LT |
41 | if (retval) |
42 | return retval; | |
726c3342 | 43 | retval = dentry->d_sb->s_op->statfs(dentry, buf); |
1da177e4 LT |
44 | if (retval == 0 && buf->f_frsize == 0) |
45 | buf->f_frsize = buf->f_bsize; | |
46 | } | |
47 | } | |
48 | return retval; | |
49 | } | |
50 | ||
51 | EXPORT_SYMBOL(vfs_statfs); | |
52 | ||
726c3342 | 53 | static int vfs_statfs_native(struct dentry *dentry, struct statfs *buf) |
1da177e4 LT |
54 | { |
55 | struct kstatfs st; | |
56 | int retval; | |
57 | ||
726c3342 | 58 | retval = vfs_statfs(dentry, &st); |
1da177e4 LT |
59 | if (retval) |
60 | return retval; | |
61 | ||
62 | if (sizeof(*buf) == sizeof(st)) | |
63 | memcpy(buf, &st, sizeof(st)); | |
64 | else { | |
65 | if (sizeof buf->f_blocks == 4) { | |
66 | if ((st.f_blocks | st.f_bfree | st.f_bavail) & | |
67 | 0xffffffff00000000ULL) | |
68 | return -EOVERFLOW; | |
69 | /* | |
70 | * f_files and f_ffree may be -1; it's okay to stuff | |
71 | * that into 32 bits | |
72 | */ | |
73 | if (st.f_files != -1 && | |
74 | (st.f_files & 0xffffffff00000000ULL)) | |
75 | return -EOVERFLOW; | |
76 | if (st.f_ffree != -1 && | |
77 | (st.f_ffree & 0xffffffff00000000ULL)) | |
78 | return -EOVERFLOW; | |
79 | } | |
80 | ||
81 | buf->f_type = st.f_type; | |
82 | buf->f_bsize = st.f_bsize; | |
83 | buf->f_blocks = st.f_blocks; | |
84 | buf->f_bfree = st.f_bfree; | |
85 | buf->f_bavail = st.f_bavail; | |
86 | buf->f_files = st.f_files; | |
87 | buf->f_ffree = st.f_ffree; | |
88 | buf->f_fsid = st.f_fsid; | |
89 | buf->f_namelen = st.f_namelen; | |
90 | buf->f_frsize = st.f_frsize; | |
91 | memset(buf->f_spare, 0, sizeof(buf->f_spare)); | |
92 | } | |
93 | return 0; | |
94 | } | |
95 | ||
726c3342 | 96 | static int vfs_statfs64(struct dentry *dentry, struct statfs64 *buf) |
1da177e4 LT |
97 | { |
98 | struct kstatfs st; | |
99 | int retval; | |
100 | ||
726c3342 | 101 | retval = vfs_statfs(dentry, &st); |
1da177e4 LT |
102 | if (retval) |
103 | return retval; | |
104 | ||
105 | if (sizeof(*buf) == sizeof(st)) | |
106 | memcpy(buf, &st, sizeof(st)); | |
107 | else { | |
108 | buf->f_type = st.f_type; | |
109 | buf->f_bsize = st.f_bsize; | |
110 | buf->f_blocks = st.f_blocks; | |
111 | buf->f_bfree = st.f_bfree; | |
112 | buf->f_bavail = st.f_bavail; | |
113 | buf->f_files = st.f_files; | |
114 | buf->f_ffree = st.f_ffree; | |
115 | buf->f_fsid = st.f_fsid; | |
116 | buf->f_namelen = st.f_namelen; | |
117 | buf->f_frsize = st.f_frsize; | |
118 | memset(buf->f_spare, 0, sizeof(buf->f_spare)); | |
119 | } | |
120 | return 0; | |
121 | } | |
122 | ||
123 | asmlinkage long sys_statfs(const char __user * path, struct statfs __user * buf) | |
124 | { | |
125 | struct nameidata nd; | |
126 | int error; | |
127 | ||
128 | error = user_path_walk(path, &nd); | |
129 | if (!error) { | |
130 | struct statfs tmp; | |
4ac91378 | 131 | error = vfs_statfs_native(nd.path.dentry, &tmp); |
1da177e4 LT |
132 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
133 | error = -EFAULT; | |
1d957f9b | 134 | path_put(&nd.path); |
1da177e4 LT |
135 | } |
136 | return error; | |
137 | } | |
138 | ||
139 | ||
140 | asmlinkage long sys_statfs64(const char __user *path, size_t sz, struct statfs64 __user *buf) | |
141 | { | |
142 | struct nameidata nd; | |
143 | long error; | |
144 | ||
145 | if (sz != sizeof(*buf)) | |
146 | return -EINVAL; | |
147 | error = user_path_walk(path, &nd); | |
148 | if (!error) { | |
149 | struct statfs64 tmp; | |
4ac91378 | 150 | error = vfs_statfs64(nd.path.dentry, &tmp); |
1da177e4 LT |
151 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
152 | error = -EFAULT; | |
1d957f9b | 153 | path_put(&nd.path); |
1da177e4 LT |
154 | } |
155 | return error; | |
156 | } | |
157 | ||
158 | ||
159 | asmlinkage long sys_fstatfs(unsigned int fd, struct statfs __user * buf) | |
160 | { | |
161 | struct file * file; | |
162 | struct statfs tmp; | |
163 | int error; | |
164 | ||
165 | error = -EBADF; | |
166 | file = fget(fd); | |
167 | if (!file) | |
168 | goto out; | |
0f7fc9e4 | 169 | error = vfs_statfs_native(file->f_path.dentry, &tmp); |
1da177e4 LT |
170 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
171 | error = -EFAULT; | |
172 | fput(file); | |
173 | out: | |
174 | return error; | |
175 | } | |
176 | ||
177 | asmlinkage long sys_fstatfs64(unsigned int fd, size_t sz, struct statfs64 __user *buf) | |
178 | { | |
179 | struct file * file; | |
180 | struct statfs64 tmp; | |
181 | int error; | |
182 | ||
183 | if (sz != sizeof(*buf)) | |
184 | return -EINVAL; | |
185 | ||
186 | error = -EBADF; | |
187 | file = fget(fd); | |
188 | if (!file) | |
189 | goto out; | |
0f7fc9e4 | 190 | error = vfs_statfs64(file->f_path.dentry, &tmp); |
1da177e4 LT |
191 | if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) |
192 | error = -EFAULT; | |
193 | fput(file); | |
194 | out: | |
195 | return error; | |
196 | } | |
197 | ||
4a30131e N |
198 | int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, |
199 | struct file *filp) | |
1da177e4 LT |
200 | { |
201 | int err; | |
202 | struct iattr newattrs; | |
203 | ||
204 | /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */ | |
205 | if (length < 0) | |
206 | return -EINVAL; | |
207 | ||
208 | newattrs.ia_size = length; | |
4a30131e | 209 | newattrs.ia_valid = ATTR_SIZE | time_attrs; |
cc4e69de MS |
210 | if (filp) { |
211 | newattrs.ia_file = filp; | |
212 | newattrs.ia_valid |= ATTR_FILE; | |
213 | } | |
1da177e4 | 214 | |
7b82dc0e LT |
215 | /* Remove suid/sgid on truncate too */ |
216 | newattrs.ia_valid |= should_remove_suid(dentry); | |
217 | ||
1b1dcc1b | 218 | mutex_lock(&dentry->d_inode->i_mutex); |
1da177e4 | 219 | err = notify_change(dentry, &newattrs); |
1b1dcc1b | 220 | mutex_unlock(&dentry->d_inode->i_mutex); |
1da177e4 LT |
221 | return err; |
222 | } | |
223 | ||
b01ec0ef | 224 | static long do_sys_truncate(const char __user * path, loff_t length) |
1da177e4 LT |
225 | { |
226 | struct nameidata nd; | |
227 | struct inode * inode; | |
228 | int error; | |
229 | ||
230 | error = -EINVAL; | |
231 | if (length < 0) /* sorry, but loff_t says... */ | |
232 | goto out; | |
233 | ||
234 | error = user_path_walk(path, &nd); | |
235 | if (error) | |
236 | goto out; | |
4ac91378 | 237 | inode = nd.path.dentry->d_inode; |
1da177e4 LT |
238 | |
239 | /* For directories it's -EISDIR, for other non-regulars - -EINVAL */ | |
240 | error = -EISDIR; | |
241 | if (S_ISDIR(inode->i_mode)) | |
242 | goto dput_and_out; | |
243 | ||
244 | error = -EINVAL; | |
245 | if (!S_ISREG(inode->i_mode)) | |
246 | goto dput_and_out; | |
247 | ||
9ac9b847 | 248 | error = mnt_want_write(nd.path.mnt); |
1da177e4 LT |
249 | if (error) |
250 | goto dput_and_out; | |
251 | ||
9ac9b847 DH |
252 | error = vfs_permission(&nd, MAY_WRITE); |
253 | if (error) | |
254 | goto mnt_drop_write_and_out; | |
1da177e4 LT |
255 | |
256 | error = -EPERM; | |
257 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
9ac9b847 | 258 | goto mnt_drop_write_and_out; |
1da177e4 | 259 | |
9700382c | 260 | error = get_write_access(inode); |
1da177e4 | 261 | if (error) |
9ac9b847 | 262 | goto mnt_drop_write_and_out; |
1da177e4 | 263 | |
9700382c | 264 | /* |
265 | * Make sure that there are no leases. get_write_access() protects | |
266 | * against the truncate racing with a lease-granting setlease(). | |
267 | */ | |
268 | error = break_lease(inode, FMODE_WRITE); | |
1da177e4 | 269 | if (error) |
9700382c | 270 | goto put_write_and_out; |
1da177e4 LT |
271 | |
272 | error = locks_verify_truncate(inode, NULL, length); | |
273 | if (!error) { | |
274 | DQUOT_INIT(inode); | |
4ac91378 | 275 | error = do_truncate(nd.path.dentry, length, 0, NULL); |
1da177e4 | 276 | } |
1da177e4 | 277 | |
9700382c | 278 | put_write_and_out: |
279 | put_write_access(inode); | |
9ac9b847 DH |
280 | mnt_drop_write_and_out: |
281 | mnt_drop_write(nd.path.mnt); | |
1da177e4 | 282 | dput_and_out: |
1d957f9b | 283 | path_put(&nd.path); |
1da177e4 LT |
284 | out: |
285 | return error; | |
286 | } | |
287 | ||
288 | asmlinkage long sys_truncate(const char __user * path, unsigned long length) | |
289 | { | |
290 | /* on 32-bit boxen it will cut the range 2^31--2^32-1 off */ | |
291 | return do_sys_truncate(path, (long)length); | |
292 | } | |
293 | ||
b01ec0ef | 294 | static long do_sys_ftruncate(unsigned int fd, loff_t length, int small) |
1da177e4 LT |
295 | { |
296 | struct inode * inode; | |
297 | struct dentry *dentry; | |
298 | struct file * file; | |
299 | int error; | |
300 | ||
301 | error = -EINVAL; | |
302 | if (length < 0) | |
303 | goto out; | |
304 | error = -EBADF; | |
305 | file = fget(fd); | |
306 | if (!file) | |
307 | goto out; | |
308 | ||
309 | /* explicitly opened as large or we are on 64-bit box */ | |
310 | if (file->f_flags & O_LARGEFILE) | |
311 | small = 0; | |
312 | ||
0f7fc9e4 | 313 | dentry = file->f_path.dentry; |
1da177e4 LT |
314 | inode = dentry->d_inode; |
315 | error = -EINVAL; | |
316 | if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE)) | |
317 | goto out_putf; | |
318 | ||
319 | error = -EINVAL; | |
320 | /* Cannot ftruncate over 2^31 bytes without large file support */ | |
321 | if (small && length > MAX_NON_LFS) | |
322 | goto out_putf; | |
323 | ||
324 | error = -EPERM; | |
325 | if (IS_APPEND(inode)) | |
326 | goto out_putf; | |
327 | ||
328 | error = locks_verify_truncate(inode, file, length); | |
329 | if (!error) | |
6e656be8 | 330 | error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file); |
1da177e4 LT |
331 | out_putf: |
332 | fput(file); | |
333 | out: | |
334 | return error; | |
335 | } | |
336 | ||
337 | asmlinkage long sys_ftruncate(unsigned int fd, unsigned long length) | |
338 | { | |
0a489cb3 | 339 | long ret = do_sys_ftruncate(fd, length, 1); |
385910f2 | 340 | /* avoid REGPARM breakage on x86: */ |
54a01510 | 341 | asmlinkage_protect(2, ret, fd, length); |
0a489cb3 | 342 | return ret; |
1da177e4 LT |
343 | } |
344 | ||
345 | /* LFS versions of truncate are only needed on 32 bit machines */ | |
346 | #if BITS_PER_LONG == 32 | |
347 | asmlinkage long sys_truncate64(const char __user * path, loff_t length) | |
348 | { | |
349 | return do_sys_truncate(path, length); | |
350 | } | |
351 | ||
352 | asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length) | |
353 | { | |
0a489cb3 | 354 | long ret = do_sys_ftruncate(fd, length, 0); |
385910f2 | 355 | /* avoid REGPARM breakage on x86: */ |
54a01510 | 356 | asmlinkage_protect(2, ret, fd, length); |
0a489cb3 | 357 | return ret; |
1da177e4 LT |
358 | } |
359 | #endif | |
360 | ||
97ac7350 AA |
361 | asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len) |
362 | { | |
363 | struct file *file; | |
364 | struct inode *inode; | |
365 | long ret = -EINVAL; | |
366 | ||
367 | if (offset < 0 || len <= 0) | |
368 | goto out; | |
369 | ||
370 | /* Return error if mode is not supported */ | |
371 | ret = -EOPNOTSUPP; | |
372 | if (mode && !(mode & FALLOC_FL_KEEP_SIZE)) | |
373 | goto out; | |
374 | ||
375 | ret = -EBADF; | |
376 | file = fget(fd); | |
377 | if (!file) | |
378 | goto out; | |
379 | if (!(file->f_mode & FMODE_WRITE)) | |
380 | goto out_fput; | |
381 | /* | |
382 | * Revalidate the write permissions, in case security policy has | |
383 | * changed since the files were opened. | |
384 | */ | |
385 | ret = security_file_permission(file, MAY_WRITE); | |
386 | if (ret) | |
387 | goto out_fput; | |
388 | ||
389 | inode = file->f_path.dentry->d_inode; | |
390 | ||
391 | ret = -ESPIPE; | |
392 | if (S_ISFIFO(inode->i_mode)) | |
393 | goto out_fput; | |
394 | ||
395 | ret = -ENODEV; | |
396 | /* | |
397 | * Let individual file system decide if it supports preallocation | |
398 | * for directories or not. | |
399 | */ | |
400 | if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) | |
401 | goto out_fput; | |
402 | ||
403 | ret = -EFBIG; | |
404 | /* Check for wrap through zero too */ | |
405 | if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0)) | |
406 | goto out_fput; | |
407 | ||
408 | if (inode->i_op && inode->i_op->fallocate) | |
409 | ret = inode->i_op->fallocate(inode, mode, offset, len); | |
410 | else | |
0d786d4a | 411 | ret = -EOPNOTSUPP; |
97ac7350 AA |
412 | |
413 | out_fput: | |
414 | fput(file); | |
415 | out: | |
416 | return ret; | |
417 | } | |
418 | ||
1da177e4 LT |
419 | /* |
420 | * access() needs to use the real uid/gid, not the effective uid/gid. | |
421 | * We do this by temporarily clearing all FS-related capabilities and | |
422 | * switching the fsuid/fsgid around to the real ones. | |
423 | */ | |
5590ff0d | 424 | asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode) |
1da177e4 LT |
425 | { |
426 | struct nameidata nd; | |
427 | int old_fsuid, old_fsgid; | |
428 | kernel_cap_t old_cap; | |
429 | int res; | |
430 | ||
431 | if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */ | |
432 | return -EINVAL; | |
433 | ||
434 | old_fsuid = current->fsuid; | |
435 | old_fsgid = current->fsgid; | |
436 | old_cap = current->cap_effective; | |
437 | ||
438 | current->fsuid = current->uid; | |
439 | current->fsgid = current->gid; | |
440 | ||
441 | /* | |
442 | * Clear the capabilities if we switch to a non-root user | |
443 | * | |
444 | * FIXME: There is a race here against sys_capset. The | |
445 | * capabilities can change yet we will restore the old | |
446 | * value below. We should hold task_capabilities_lock, | |
447 | * but we cannot because user_path_walk can sleep. | |
448 | */ | |
449 | if (current->uid) | |
450 | cap_clear(current->cap_effective); | |
451 | else | |
452 | current->cap_effective = current->cap_permitted; | |
453 | ||
5590ff0d | 454 | res = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd); |
6902d925 DH |
455 | if (res) |
456 | goto out; | |
457 | ||
458 | res = vfs_permission(&nd, mode); | |
459 | /* SuS v2 requires we report a read only fs too */ | |
460 | if(res || !(mode & S_IWOTH) || | |
4ac91378 | 461 | special_file(nd.path.dentry->d_inode->i_mode)) |
6902d925 | 462 | goto out_path_release; |
2f676cbc DH |
463 | /* |
464 | * This is a rare case where using __mnt_is_readonly() | |
465 | * is OK without a mnt_want/drop_write() pair. Since | |
466 | * no actual write to the fs is performed here, we do | |
467 | * not need to telegraph to that to anyone. | |
468 | * | |
469 | * By doing this, we accept that this access is | |
470 | * inherently racy and know that the fs may change | |
471 | * state before we even see this result. | |
472 | */ | |
473 | if (__mnt_is_readonly(nd.path.mnt)) | |
6902d925 | 474 | res = -EROFS; |
1da177e4 | 475 | |
6902d925 | 476 | out_path_release: |
1d957f9b | 477 | path_put(&nd.path); |
6902d925 | 478 | out: |
1da177e4 LT |
479 | current->fsuid = old_fsuid; |
480 | current->fsgid = old_fsgid; | |
481 | current->cap_effective = old_cap; | |
482 | ||
483 | return res; | |
484 | } | |
485 | ||
5590ff0d UD |
486 | asmlinkage long sys_access(const char __user *filename, int mode) |
487 | { | |
488 | return sys_faccessat(AT_FDCWD, filename, mode); | |
489 | } | |
490 | ||
1da177e4 LT |
491 | asmlinkage long sys_chdir(const char __user * filename) |
492 | { | |
493 | struct nameidata nd; | |
494 | int error; | |
495 | ||
650a8983 MS |
496 | error = __user_walk(filename, |
497 | LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_CHDIR, &nd); | |
1da177e4 LT |
498 | if (error) |
499 | goto out; | |
500 | ||
e4543edd | 501 | error = vfs_permission(&nd, MAY_EXEC); |
1da177e4 LT |
502 | if (error) |
503 | goto dput_and_out; | |
504 | ||
ac748a09 | 505 | set_fs_pwd(current->fs, &nd.path); |
1da177e4 LT |
506 | |
507 | dput_and_out: | |
1d957f9b | 508 | path_put(&nd.path); |
1da177e4 LT |
509 | out: |
510 | return error; | |
511 | } | |
512 | ||
513 | asmlinkage long sys_fchdir(unsigned int fd) | |
514 | { | |
515 | struct file *file; | |
1da177e4 | 516 | struct inode *inode; |
1da177e4 LT |
517 | int error; |
518 | ||
519 | error = -EBADF; | |
520 | file = fget(fd); | |
521 | if (!file) | |
522 | goto out; | |
523 | ||
ac748a09 | 524 | inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
525 | |
526 | error = -ENOTDIR; | |
527 | if (!S_ISDIR(inode->i_mode)) | |
528 | goto out_putf; | |
529 | ||
8c744fb8 | 530 | error = file_permission(file, MAY_EXEC); |
1da177e4 | 531 | if (!error) |
ac748a09 | 532 | set_fs_pwd(current->fs, &file->f_path); |
1da177e4 LT |
533 | out_putf: |
534 | fput(file); | |
535 | out: | |
536 | return error; | |
537 | } | |
538 | ||
539 | asmlinkage long sys_chroot(const char __user * filename) | |
540 | { | |
541 | struct nameidata nd; | |
542 | int error; | |
543 | ||
544 | error = __user_walk(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY | LOOKUP_NOALT, &nd); | |
545 | if (error) | |
546 | goto out; | |
547 | ||
e4543edd | 548 | error = vfs_permission(&nd, MAY_EXEC); |
1da177e4 LT |
549 | if (error) |
550 | goto dput_and_out; | |
551 | ||
552 | error = -EPERM; | |
553 | if (!capable(CAP_SYS_CHROOT)) | |
554 | goto dput_and_out; | |
555 | ||
ac748a09 | 556 | set_fs_root(current->fs, &nd.path); |
1da177e4 LT |
557 | set_fs_altroot(); |
558 | error = 0; | |
559 | dput_and_out: | |
1d957f9b | 560 | path_put(&nd.path); |
1da177e4 LT |
561 | out: |
562 | return error; | |
563 | } | |
564 | ||
565 | asmlinkage long sys_fchmod(unsigned int fd, mode_t mode) | |
566 | { | |
567 | struct inode * inode; | |
568 | struct dentry * dentry; | |
569 | struct file * file; | |
570 | int err = -EBADF; | |
571 | struct iattr newattrs; | |
572 | ||
573 | file = fget(fd); | |
574 | if (!file) | |
575 | goto out; | |
576 | ||
0f7fc9e4 | 577 | dentry = file->f_path.dentry; |
1da177e4 LT |
578 | inode = dentry->d_inode; |
579 | ||
5a190ae6 | 580 | audit_inode(NULL, dentry); |
73241ccc | 581 | |
2af482a7 DH |
582 | err = mnt_want_write(file->f_path.mnt); |
583 | if (err) | |
1da177e4 LT |
584 | goto out_putf; |
585 | err = -EPERM; | |
586 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
2af482a7 | 587 | goto out_drop_write; |
1b1dcc1b | 588 | mutex_lock(&inode->i_mutex); |
1da177e4 LT |
589 | if (mode == (mode_t) -1) |
590 | mode = inode->i_mode; | |
591 | newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); | |
592 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; | |
593 | err = notify_change(dentry, &newattrs); | |
1b1dcc1b | 594 | mutex_unlock(&inode->i_mutex); |
1da177e4 | 595 | |
2af482a7 DH |
596 | out_drop_write: |
597 | mnt_drop_write(file->f_path.mnt); | |
1da177e4 LT |
598 | out_putf: |
599 | fput(file); | |
600 | out: | |
601 | return err; | |
602 | } | |
603 | ||
5590ff0d UD |
604 | asmlinkage long sys_fchmodat(int dfd, const char __user *filename, |
605 | mode_t mode) | |
1da177e4 LT |
606 | { |
607 | struct nameidata nd; | |
608 | struct inode * inode; | |
609 | int error; | |
610 | struct iattr newattrs; | |
611 | ||
5590ff0d | 612 | error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd); |
1da177e4 LT |
613 | if (error) |
614 | goto out; | |
4ac91378 | 615 | inode = nd.path.dentry->d_inode; |
1da177e4 | 616 | |
2af482a7 DH |
617 | error = mnt_want_write(nd.path.mnt); |
618 | if (error) | |
1da177e4 LT |
619 | goto dput_and_out; |
620 | ||
621 | error = -EPERM; | |
622 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
2af482a7 | 623 | goto out_drop_write; |
1da177e4 | 624 | |
1b1dcc1b | 625 | mutex_lock(&inode->i_mutex); |
1da177e4 LT |
626 | if (mode == (mode_t) -1) |
627 | mode = inode->i_mode; | |
628 | newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); | |
629 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; | |
4ac91378 | 630 | error = notify_change(nd.path.dentry, &newattrs); |
1b1dcc1b | 631 | mutex_unlock(&inode->i_mutex); |
1da177e4 | 632 | |
2af482a7 DH |
633 | out_drop_write: |
634 | mnt_drop_write(nd.path.mnt); | |
1da177e4 | 635 | dput_and_out: |
1d957f9b | 636 | path_put(&nd.path); |
1da177e4 LT |
637 | out: |
638 | return error; | |
639 | } | |
640 | ||
5590ff0d UD |
641 | asmlinkage long sys_chmod(const char __user *filename, mode_t mode) |
642 | { | |
643 | return sys_fchmodat(AT_FDCWD, filename, mode); | |
644 | } | |
645 | ||
1da177e4 LT |
646 | static int chown_common(struct dentry * dentry, uid_t user, gid_t group) |
647 | { | |
648 | struct inode * inode; | |
649 | int error; | |
650 | struct iattr newattrs; | |
651 | ||
652 | error = -ENOENT; | |
653 | if (!(inode = dentry->d_inode)) { | |
654 | printk(KERN_ERR "chown_common: NULL inode\n"); | |
655 | goto out; | |
656 | } | |
1da177e4 LT |
657 | error = -EPERM; |
658 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | |
659 | goto out; | |
660 | newattrs.ia_valid = ATTR_CTIME; | |
661 | if (user != (uid_t) -1) { | |
662 | newattrs.ia_valid |= ATTR_UID; | |
663 | newattrs.ia_uid = user; | |
664 | } | |
665 | if (group != (gid_t) -1) { | |
666 | newattrs.ia_valid |= ATTR_GID; | |
667 | newattrs.ia_gid = group; | |
668 | } | |
669 | if (!S_ISDIR(inode->i_mode)) | |
b5376771 SH |
670 | newattrs.ia_valid |= |
671 | ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV; | |
1b1dcc1b | 672 | mutex_lock(&inode->i_mutex); |
1da177e4 | 673 | error = notify_change(dentry, &newattrs); |
1b1dcc1b | 674 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
675 | out: |
676 | return error; | |
677 | } | |
678 | ||
679 | asmlinkage long sys_chown(const char __user * filename, uid_t user, gid_t group) | |
680 | { | |
681 | struct nameidata nd; | |
682 | int error; | |
683 | ||
684 | error = user_path_walk(filename, &nd); | |
6902d925 DH |
685 | if (error) |
686 | goto out; | |
2af482a7 DH |
687 | error = mnt_want_write(nd.path.mnt); |
688 | if (error) | |
689 | goto out_release; | |
4ac91378 | 690 | error = chown_common(nd.path.dentry, user, group); |
2af482a7 DH |
691 | mnt_drop_write(nd.path.mnt); |
692 | out_release: | |
1d957f9b | 693 | path_put(&nd.path); |
6902d925 | 694 | out: |
1da177e4 LT |
695 | return error; |
696 | } | |
697 | ||
5590ff0d UD |
698 | asmlinkage long sys_fchownat(int dfd, const char __user *filename, uid_t user, |
699 | gid_t group, int flag) | |
700 | { | |
701 | struct nameidata nd; | |
702 | int error = -EINVAL; | |
703 | int follow; | |
704 | ||
705 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
706 | goto out; | |
707 | ||
708 | follow = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; | |
709 | error = __user_walk_fd(dfd, filename, follow, &nd); | |
6902d925 DH |
710 | if (error) |
711 | goto out; | |
2af482a7 DH |
712 | error = mnt_want_write(nd.path.mnt); |
713 | if (error) | |
714 | goto out_release; | |
4ac91378 | 715 | error = chown_common(nd.path.dentry, user, group); |
2af482a7 DH |
716 | mnt_drop_write(nd.path.mnt); |
717 | out_release: | |
1d957f9b | 718 | path_put(&nd.path); |
5590ff0d UD |
719 | out: |
720 | return error; | |
721 | } | |
722 | ||
1da177e4 LT |
723 | asmlinkage long sys_lchown(const char __user * filename, uid_t user, gid_t group) |
724 | { | |
725 | struct nameidata nd; | |
726 | int error; | |
727 | ||
728 | error = user_path_walk_link(filename, &nd); | |
6902d925 DH |
729 | if (error) |
730 | goto out; | |
2af482a7 DH |
731 | error = mnt_want_write(nd.path.mnt); |
732 | if (error) | |
733 | goto out_release; | |
4ac91378 | 734 | error = chown_common(nd.path.dentry, user, group); |
2af482a7 DH |
735 | mnt_drop_write(nd.path.mnt); |
736 | out_release: | |
1d957f9b | 737 | path_put(&nd.path); |
6902d925 | 738 | out: |
1da177e4 LT |
739 | return error; |
740 | } | |
741 | ||
742 | ||
743 | asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group) | |
744 | { | |
745 | struct file * file; | |
746 | int error = -EBADF; | |
6902d925 | 747 | struct dentry * dentry; |
1da177e4 LT |
748 | |
749 | file = fget(fd); | |
6902d925 DH |
750 | if (!file) |
751 | goto out; | |
752 | ||
2af482a7 DH |
753 | error = mnt_want_write(file->f_path.mnt); |
754 | if (error) | |
755 | goto out_fput; | |
0f7fc9e4 | 756 | dentry = file->f_path.dentry; |
5a190ae6 | 757 | audit_inode(NULL, dentry); |
6902d925 | 758 | error = chown_common(dentry, user, group); |
2af482a7 DH |
759 | mnt_drop_write(file->f_path.mnt); |
760 | out_fput: | |
6902d925 DH |
761 | fput(file); |
762 | out: | |
1da177e4 LT |
763 | return error; |
764 | } | |
765 | ||
4a3fd211 DH |
766 | /* |
767 | * You have to be very careful that these write | |
768 | * counts get cleaned up in error cases and | |
769 | * upon __fput(). This should probably never | |
770 | * be called outside of __dentry_open(). | |
771 | */ | |
772 | static inline int __get_file_write_access(struct inode *inode, | |
773 | struct vfsmount *mnt) | |
774 | { | |
775 | int error; | |
776 | error = get_write_access(inode); | |
777 | if (error) | |
778 | return error; | |
779 | /* | |
780 | * Do not take mount writer counts on | |
781 | * special files since no writes to | |
782 | * the mount itself will occur. | |
783 | */ | |
784 | if (!special_file(inode->i_mode)) { | |
785 | /* | |
786 | * Balanced in __fput() | |
787 | */ | |
788 | error = mnt_want_write(mnt); | |
789 | if (error) | |
790 | put_write_access(inode); | |
791 | } | |
792 | return error; | |
793 | } | |
794 | ||
a1a5b3d9 | 795 | static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, |
834f2a4a TM |
796 | int flags, struct file *f, |
797 | int (*open)(struct inode *, struct file *)) | |
1da177e4 | 798 | { |
1da177e4 LT |
799 | struct inode *inode; |
800 | int error; | |
801 | ||
1da177e4 | 802 | f->f_flags = flags; |
a1a5b3d9 PS |
803 | f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK | |
804 | FMODE_PREAD | FMODE_PWRITE; | |
1da177e4 LT |
805 | inode = dentry->d_inode; |
806 | if (f->f_mode & FMODE_WRITE) { | |
4a3fd211 | 807 | error = __get_file_write_access(inode, mnt); |
1da177e4 LT |
808 | if (error) |
809 | goto cleanup_file; | |
ad775f5a DH |
810 | if (!special_file(inode->i_mode)) |
811 | file_take_write(f); | |
1da177e4 LT |
812 | } |
813 | ||
814 | f->f_mapping = inode->i_mapping; | |
0f7fc9e4 JJS |
815 | f->f_path.dentry = dentry; |
816 | f->f_path.mnt = mnt; | |
1da177e4 LT |
817 | f->f_pos = 0; |
818 | f->f_op = fops_get(inode->i_fop); | |
819 | file_move(f, &inode->i_sb->s_files); | |
820 | ||
788e7dd4 YN |
821 | error = security_dentry_open(f); |
822 | if (error) | |
823 | goto cleanup_all; | |
824 | ||
834f2a4a TM |
825 | if (!open && f->f_op) |
826 | open = f->f_op->open; | |
827 | if (open) { | |
828 | error = open(inode, f); | |
1da177e4 LT |
829 | if (error) |
830 | goto cleanup_all; | |
831 | } | |
834f2a4a | 832 | |
1da177e4 LT |
833 | f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); |
834 | ||
835 | file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); | |
836 | ||
837 | /* NB: we're sure to have correct a_ops only after f_op->open */ | |
838 | if (f->f_flags & O_DIRECT) { | |
ceffc078 CO |
839 | if (!f->f_mapping->a_ops || |
840 | ((!f->f_mapping->a_ops->direct_IO) && | |
70688e4d | 841 | (!f->f_mapping->a_ops->get_xip_mem))) { |
1da177e4 LT |
842 | fput(f); |
843 | f = ERR_PTR(-EINVAL); | |
844 | } | |
845 | } | |
846 | ||
847 | return f; | |
848 | ||
849 | cleanup_all: | |
850 | fops_put(f->f_op); | |
4a3fd211 | 851 | if (f->f_mode & FMODE_WRITE) { |
1da177e4 | 852 | put_write_access(inode); |
ad775f5a DH |
853 | if (!special_file(inode->i_mode)) { |
854 | /* | |
855 | * We don't consider this a real | |
856 | * mnt_want/drop_write() pair | |
857 | * because it all happenend right | |
858 | * here, so just reset the state. | |
859 | */ | |
860 | file_reset_write(f); | |
4a3fd211 | 861 | mnt_drop_write(mnt); |
ad775f5a | 862 | } |
4a3fd211 | 863 | } |
1da177e4 | 864 | file_kill(f); |
0f7fc9e4 JJS |
865 | f->f_path.dentry = NULL; |
866 | f->f_path.mnt = NULL; | |
1da177e4 LT |
867 | cleanup_file: |
868 | put_filp(f); | |
1da177e4 LT |
869 | dput(dentry); |
870 | mntput(mnt); | |
871 | return ERR_PTR(error); | |
872 | } | |
873 | ||
834f2a4a TM |
874 | /** |
875 | * lookup_instantiate_filp - instantiates the open intent filp | |
876 | * @nd: pointer to nameidata | |
877 | * @dentry: pointer to dentry | |
878 | * @open: open callback | |
879 | * | |
880 | * Helper for filesystems that want to use lookup open intents and pass back | |
881 | * a fully instantiated struct file to the caller. | |
882 | * This function is meant to be called from within a filesystem's | |
883 | * lookup method. | |
9a56c213 OD |
884 | * Beware of calling it for non-regular files! Those ->open methods might block |
885 | * (e.g. in fifo_open), leaving you with parent locked (and in case of fifo, | |
886 | * leading to a deadlock, as nobody can open that fifo anymore, because | |
887 | * another process to open fifo will block on locked parent when doing lookup). | |
834f2a4a TM |
888 | * Note that in case of error, nd->intent.open.file is destroyed, but the |
889 | * path information remains valid. | |
890 | * If the open callback is set to NULL, then the standard f_op->open() | |
891 | * filesystem callback is substituted. | |
892 | */ | |
893 | struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry, | |
894 | int (*open)(struct inode *, struct file *)) | |
895 | { | |
896 | if (IS_ERR(nd->intent.open.file)) | |
897 | goto out; | |
898 | if (IS_ERR(dentry)) | |
899 | goto out_err; | |
4ac91378 | 900 | nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->path.mnt), |
834f2a4a TM |
901 | nd->intent.open.flags - 1, |
902 | nd->intent.open.file, | |
903 | open); | |
904 | out: | |
905 | return nd->intent.open.file; | |
906 | out_err: | |
907 | release_open_intent(nd); | |
908 | nd->intent.open.file = (struct file *)dentry; | |
909 | goto out; | |
910 | } | |
911 | EXPORT_SYMBOL_GPL(lookup_instantiate_filp); | |
912 | ||
913 | /** | |
914 | * nameidata_to_filp - convert a nameidata to an open filp. | |
915 | * @nd: pointer to nameidata | |
916 | * @flags: open flags | |
917 | * | |
918 | * Note that this function destroys the original nameidata | |
919 | */ | |
920 | struct file *nameidata_to_filp(struct nameidata *nd, int flags) | |
921 | { | |
922 | struct file *filp; | |
923 | ||
924 | /* Pick up the filp from the open intent */ | |
925 | filp = nd->intent.open.file; | |
926 | /* Has the filesystem initialised the file for us? */ | |
0f7fc9e4 | 927 | if (filp->f_path.dentry == NULL) |
4ac91378 JB |
928 | filp = __dentry_open(nd->path.dentry, nd->path.mnt, flags, filp, |
929 | NULL); | |
834f2a4a | 930 | else |
1d957f9b | 931 | path_put(&nd->path); |
834f2a4a TM |
932 | return filp; |
933 | } | |
934 | ||
6fdcc216 PS |
935 | /* |
936 | * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an | |
937 | * error. | |
938 | */ | |
a1a5b3d9 PS |
939 | struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) |
940 | { | |
941 | int error; | |
942 | struct file *f; | |
943 | ||
322ee5b3 CH |
944 | /* |
945 | * We must always pass in a valid mount pointer. Historically | |
946 | * callers got away with not passing it, but we must enforce this at | |
947 | * the earliest possible point now to avoid strange problems deep in the | |
948 | * filesystem stack. | |
949 | */ | |
950 | if (!mnt) { | |
951 | printk(KERN_WARNING "%s called with NULL vfsmount\n", __func__); | |
952 | dump_stack(); | |
953 | return ERR_PTR(-EINVAL); | |
954 | } | |
955 | ||
a1a5b3d9 PS |
956 | error = -ENFILE; |
957 | f = get_empty_filp(); | |
6fdcc216 PS |
958 | if (f == NULL) { |
959 | dput(dentry); | |
960 | mntput(mnt); | |
a1a5b3d9 | 961 | return ERR_PTR(error); |
6fdcc216 | 962 | } |
a1a5b3d9 | 963 | |
834f2a4a | 964 | return __dentry_open(dentry, mnt, flags, f, NULL); |
a1a5b3d9 | 965 | } |
1da177e4 LT |
966 | EXPORT_SYMBOL(dentry_open); |
967 | ||
968 | /* | |
969 | * Find an empty file descriptor entry, and mark it busy. | |
970 | */ | |
4a19542e | 971 | int get_unused_fd_flags(int flags) |
1da177e4 LT |
972 | { |
973 | struct files_struct * files = current->files; | |
974 | int fd, error; | |
badf1662 | 975 | struct fdtable *fdt; |
1da177e4 LT |
976 | |
977 | error = -EMFILE; | |
978 | spin_lock(&files->file_lock); | |
979 | ||
980 | repeat: | |
badf1662 | 981 | fdt = files_fdtable(files); |
bbea9f69 | 982 | fd = find_next_zero_bit(fdt->open_fds->fds_bits, fdt->max_fds, |
0c9e63fd | 983 | files->next_fd); |
1da177e4 LT |
984 | |
985 | /* | |
986 | * N.B. For clone tasks sharing a files structure, this test | |
987 | * will limit the total number of files that can be opened. | |
988 | */ | |
989 | if (fd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | |
990 | goto out; | |
991 | ||
992 | /* Do we need to expand the fd array or fd set? */ | |
993 | error = expand_files(files, fd); | |
994 | if (error < 0) | |
995 | goto out; | |
996 | ||
997 | if (error) { | |
998 | /* | |
999 | * If we needed to expand the fs array we | |
1000 | * might have blocked - try again. | |
1001 | */ | |
1002 | error = -EMFILE; | |
1003 | goto repeat; | |
1004 | } | |
1005 | ||
badf1662 | 1006 | FD_SET(fd, fdt->open_fds); |
f23513e8 UD |
1007 | if (flags & O_CLOEXEC) |
1008 | FD_SET(fd, fdt->close_on_exec); | |
1009 | else | |
1010 | FD_CLR(fd, fdt->close_on_exec); | |
0c9e63fd | 1011 | files->next_fd = fd + 1; |
1da177e4 LT |
1012 | #if 1 |
1013 | /* Sanity check */ | |
badf1662 | 1014 | if (fdt->fd[fd] != NULL) { |
1da177e4 | 1015 | printk(KERN_WARNING "get_unused_fd: slot %d not NULL!\n", fd); |
badf1662 | 1016 | fdt->fd[fd] = NULL; |
1da177e4 LT |
1017 | } |
1018 | #endif | |
1019 | error = fd; | |
1020 | ||
1021 | out: | |
1022 | spin_unlock(&files->file_lock); | |
1023 | return error; | |
1024 | } | |
1025 | ||
f23513e8 UD |
1026 | int get_unused_fd(void) |
1027 | { | |
1028 | return get_unused_fd_flags(0); | |
1029 | } | |
1030 | ||
1da177e4 LT |
1031 | EXPORT_SYMBOL(get_unused_fd); |
1032 | ||
b01ec0ef | 1033 | static void __put_unused_fd(struct files_struct *files, unsigned int fd) |
1da177e4 | 1034 | { |
badf1662 DS |
1035 | struct fdtable *fdt = files_fdtable(files); |
1036 | __FD_CLR(fd, fdt->open_fds); | |
0c9e63fd ED |
1037 | if (fd < files->next_fd) |
1038 | files->next_fd = fd; | |
1da177e4 LT |
1039 | } |
1040 | ||
fc9b52cd | 1041 | void put_unused_fd(unsigned int fd) |
1da177e4 LT |
1042 | { |
1043 | struct files_struct *files = current->files; | |
1044 | spin_lock(&files->file_lock); | |
1045 | __put_unused_fd(files, fd); | |
1046 | spin_unlock(&files->file_lock); | |
1047 | } | |
1048 | ||
1049 | EXPORT_SYMBOL(put_unused_fd); | |
1050 | ||
1051 | /* | |
5590ff0d | 1052 | * Install a file pointer in the fd array. |
1da177e4 LT |
1053 | * |
1054 | * The VFS is full of places where we drop the files lock between | |
1055 | * setting the open_fds bitmap and installing the file in the file | |
1056 | * array. At any such point, we are vulnerable to a dup2() race | |
1057 | * installing a file in the array before us. We need to detect this and | |
1058 | * fput() the struct file we are about to overwrite in this case. | |
1059 | * | |
1060 | * It should never happen - if we allow dup2() do it, _really_ bad things | |
1061 | * will follow. | |
1062 | */ | |
1063 | ||
fc9b52cd | 1064 | void fd_install(unsigned int fd, struct file *file) |
1da177e4 LT |
1065 | { |
1066 | struct files_struct *files = current->files; | |
badf1662 | 1067 | struct fdtable *fdt; |
1da177e4 | 1068 | spin_lock(&files->file_lock); |
badf1662 | 1069 | fdt = files_fdtable(files); |
ab2af1f5 DS |
1070 | BUG_ON(fdt->fd[fd] != NULL); |
1071 | rcu_assign_pointer(fdt->fd[fd], file); | |
1da177e4 LT |
1072 | spin_unlock(&files->file_lock); |
1073 | } | |
1074 | ||
1075 | EXPORT_SYMBOL(fd_install); | |
1076 | ||
5590ff0d | 1077 | long do_sys_open(int dfd, const char __user *filename, int flags, int mode) |
1da177e4 | 1078 | { |
e922efc3 MS |
1079 | char *tmp = getname(filename); |
1080 | int fd = PTR_ERR(tmp); | |
1da177e4 | 1081 | |
1da177e4 | 1082 | if (!IS_ERR(tmp)) { |
f23513e8 | 1083 | fd = get_unused_fd_flags(flags); |
1da177e4 | 1084 | if (fd >= 0) { |
5590ff0d | 1085 | struct file *f = do_filp_open(dfd, tmp, flags, mode); |
fed2fc18 TN |
1086 | if (IS_ERR(f)) { |
1087 | put_unused_fd(fd); | |
1088 | fd = PTR_ERR(f); | |
1089 | } else { | |
0f7fc9e4 | 1090 | fsnotify_open(f->f_path.dentry); |
fed2fc18 TN |
1091 | fd_install(fd, f); |
1092 | } | |
1da177e4 | 1093 | } |
1da177e4 LT |
1094 | putname(tmp); |
1095 | } | |
1096 | return fd; | |
1da177e4 | 1097 | } |
e922efc3 MS |
1098 | |
1099 | asmlinkage long sys_open(const char __user *filename, int flags, int mode) | |
1100 | { | |
385910f2 LT |
1101 | long ret; |
1102 | ||
e922efc3 MS |
1103 | if (force_o_largefile()) |
1104 | flags |= O_LARGEFILE; | |
1105 | ||
385910f2 LT |
1106 | ret = do_sys_open(AT_FDCWD, filename, flags, mode); |
1107 | /* avoid REGPARM breakage on x86: */ | |
54a01510 | 1108 | asmlinkage_protect(3, ret, filename, flags, mode); |
385910f2 | 1109 | return ret; |
e922efc3 | 1110 | } |
1da177e4 | 1111 | |
5590ff0d UD |
1112 | asmlinkage long sys_openat(int dfd, const char __user *filename, int flags, |
1113 | int mode) | |
1114 | { | |
385910f2 LT |
1115 | long ret; |
1116 | ||
5590ff0d UD |
1117 | if (force_o_largefile()) |
1118 | flags |= O_LARGEFILE; | |
1119 | ||
385910f2 LT |
1120 | ret = do_sys_open(dfd, filename, flags, mode); |
1121 | /* avoid REGPARM breakage on x86: */ | |
54a01510 | 1122 | asmlinkage_protect(4, ret, dfd, filename, flags, mode); |
385910f2 | 1123 | return ret; |
5590ff0d | 1124 | } |
5590ff0d | 1125 | |
1da177e4 LT |
1126 | #ifndef __alpha__ |
1127 | ||
1128 | /* | |
1129 | * For backward compatibility? Maybe this should be moved | |
1130 | * into arch/i386 instead? | |
1131 | */ | |
1132 | asmlinkage long sys_creat(const char __user * pathname, int mode) | |
1133 | { | |
1134 | return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode); | |
1135 | } | |
1136 | ||
1137 | #endif | |
1138 | ||
1139 | /* | |
1140 | * "id" is the POSIX thread ID. We use the | |
1141 | * files pointer for this.. | |
1142 | */ | |
1143 | int filp_close(struct file *filp, fl_owner_t id) | |
1144 | { | |
45778ca8 | 1145 | int retval = 0; |
1da177e4 LT |
1146 | |
1147 | if (!file_count(filp)) { | |
1148 | printk(KERN_ERR "VFS: Close: file count is 0\n"); | |
45778ca8 | 1149 | return 0; |
1da177e4 LT |
1150 | } |
1151 | ||
45778ca8 | 1152 | if (filp->f_op && filp->f_op->flush) |
75e1fcc0 | 1153 | retval = filp->f_op->flush(filp, id); |
1da177e4 LT |
1154 | |
1155 | dnotify_flush(filp, id); | |
1156 | locks_remove_posix(filp, id); | |
1157 | fput(filp); | |
1158 | return retval; | |
1159 | } | |
1160 | ||
1161 | EXPORT_SYMBOL(filp_close); | |
1162 | ||
1163 | /* | |
1164 | * Careful here! We test whether the file pointer is NULL before | |
1165 | * releasing the fd. This ensures that one clone task can't release | |
1166 | * an fd while another clone is opening it. | |
1167 | */ | |
1168 | asmlinkage long sys_close(unsigned int fd) | |
1169 | { | |
1170 | struct file * filp; | |
1171 | struct files_struct *files = current->files; | |
badf1662 | 1172 | struct fdtable *fdt; |
ee731f4f | 1173 | int retval; |
1da177e4 LT |
1174 | |
1175 | spin_lock(&files->file_lock); | |
badf1662 DS |
1176 | fdt = files_fdtable(files); |
1177 | if (fd >= fdt->max_fds) | |
1da177e4 | 1178 | goto out_unlock; |
badf1662 | 1179 | filp = fdt->fd[fd]; |
1da177e4 LT |
1180 | if (!filp) |
1181 | goto out_unlock; | |
ab2af1f5 | 1182 | rcu_assign_pointer(fdt->fd[fd], NULL); |
badf1662 | 1183 | FD_CLR(fd, fdt->close_on_exec); |
1da177e4 LT |
1184 | __put_unused_fd(files, fd); |
1185 | spin_unlock(&files->file_lock); | |
ee731f4f EP |
1186 | retval = filp_close(filp, files); |
1187 | ||
1188 | /* can't restart close syscall because file table entry was cleared */ | |
1189 | if (unlikely(retval == -ERESTARTSYS || | |
1190 | retval == -ERESTARTNOINTR || | |
1191 | retval == -ERESTARTNOHAND || | |
1192 | retval == -ERESTART_RESTARTBLOCK)) | |
1193 | retval = -EINTR; | |
1194 | ||
1195 | return retval; | |
1da177e4 LT |
1196 | |
1197 | out_unlock: | |
1198 | spin_unlock(&files->file_lock); | |
1199 | return -EBADF; | |
1200 | } | |
1201 | ||
1202 | EXPORT_SYMBOL(sys_close); | |
1203 | ||
1204 | /* | |
1205 | * This routine simulates a hangup on the tty, to arrange that users | |
1206 | * are given clean terminals at login time. | |
1207 | */ | |
1208 | asmlinkage long sys_vhangup(void) | |
1209 | { | |
1210 | if (capable(CAP_SYS_TTY_CONFIG)) { | |
24ec839c | 1211 | /* XXX: this needs locking */ |
1da177e4 LT |
1212 | tty_vhangup(current->signal->tty); |
1213 | return 0; | |
1214 | } | |
1215 | return -EPERM; | |
1216 | } | |
1217 | ||
1218 | /* | |
1219 | * Called when an inode is about to be open. | |
1220 | * We use this to disallow opening large files on 32bit systems if | |
1221 | * the caller didn't specify O_LARGEFILE. On 64bit systems we force | |
1222 | * on this flag in sys_open. | |
1223 | */ | |
1224 | int generic_file_open(struct inode * inode, struct file * filp) | |
1225 | { | |
1226 | if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS) | |
a9c62a18 | 1227 | return -EOVERFLOW; |
1da177e4 LT |
1228 | return 0; |
1229 | } | |
1230 | ||
1231 | EXPORT_SYMBOL(generic_file_open); | |
1232 | ||
1233 | /* | |
1234 | * This is used by subsystems that don't want seekable | |
1235 | * file descriptors | |
1236 | */ | |
1237 | int nonseekable_open(struct inode *inode, struct file *filp) | |
1238 | { | |
1239 | filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE); | |
1240 | return 0; | |
1241 | } | |
1242 | ||
1243 | EXPORT_SYMBOL(nonseekable_open); |