Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/fs/readdir.c | |
4 | * | |
5 | * Copyright (C) 1995 Linus Torvalds | |
6 | */ | |
7 | ||
85c9fe8f | 8 | #include <linux/stddef.h> |
022a1692 | 9 | #include <linux/kernel.h> |
630d9c47 | 10 | #include <linux/export.h> |
1da177e4 LT |
11 | #include <linux/time.h> |
12 | #include <linux/mm.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/stat.h> | |
15 | #include <linux/file.h> | |
1da177e4 | 16 | #include <linux/fs.h> |
d4c7cf6c | 17 | #include <linux/fsnotify.h> |
1da177e4 LT |
18 | #include <linux/dirent.h> |
19 | #include <linux/security.h> | |
20 | #include <linux/syscalls.h> | |
21 | #include <linux/unistd.h> | |
0460b2a2 | 22 | #include <linux/compat.h> |
7c0f6ba6 | 23 | #include <linux/uaccess.h> |
1da177e4 | 24 | |
9f79b78e LT |
25 | #include <asm/unaligned.h> |
26 | ||
27 | /* | |
28 | * Note the "unsafe_put_user() semantics: we goto a | |
29 | * label for errors. | |
30 | * | |
31 | * Also note how we use a "while()" loop here, even though | |
32 | * only the biggest size needs to loop. The compiler (well, | |
33 | * at least gcc) is smart enough to turn the smaller sizes | |
34 | * into just if-statements, and this way we don't need to | |
35 | * care whether 'u64' or 'u32' is the biggest size. | |
36 | */ | |
37 | #define unsafe_copy_loop(dst, src, len, type, label) \ | |
38 | while (len >= sizeof(type)) { \ | |
39 | unsafe_put_user(get_unaligned((type *)src), \ | |
40 | (type __user *)dst, label); \ | |
41 | dst += sizeof(type); \ | |
42 | src += sizeof(type); \ | |
43 | len -= sizeof(type); \ | |
44 | } | |
45 | ||
46 | /* | |
47 | * We avoid doing 64-bit copies on 32-bit architectures. They | |
48 | * might be better, but the component names are mostly small, | |
49 | * and the 64-bit cases can end up being much more complex and | |
50 | * put much more register pressure on the code, so it's likely | |
51 | * not worth the pain of unaligned accesses etc. | |
52 | * | |
53 | * So limit the copies to "unsigned long" size. I did verify | |
54 | * that at least the x86-32 case is ok without this limiting, | |
55 | * but I worry about random other legacy 32-bit cases that | |
56 | * might not do as well. | |
57 | */ | |
58 | #define unsafe_copy_type(dst, src, len, type, label) do { \ | |
59 | if (sizeof(type) <= sizeof(unsigned long)) \ | |
60 | unsafe_copy_loop(dst, src, len, type, label); \ | |
61 | } while (0) | |
62 | ||
63 | /* | |
64 | * Copy the dirent name to user space, and NUL-terminate | |
65 | * it. This should not be a function call, since we're doing | |
66 | * the copy inside a "user_access_begin/end()" section. | |
67 | */ | |
68 | #define unsafe_copy_dirent_name(_dst, _src, _len, label) do { \ | |
69 | char __user *dst = (_dst); \ | |
70 | const char *src = (_src); \ | |
71 | size_t len = (_len); \ | |
72 | unsafe_copy_type(dst, src, len, u64, label); \ | |
73 | unsafe_copy_type(dst, src, len, u32, label); \ | |
74 | unsafe_copy_type(dst, src, len, u16, label); \ | |
75 | unsafe_copy_type(dst, src, len, u8, label); \ | |
76 | unsafe_put_user(0, dst, label); \ | |
77 | } while (0) | |
78 | ||
79 | ||
5c0ba4e0 | 80 | int iterate_dir(struct file *file, struct dir_context *ctx) |
1da177e4 | 81 | { |
496ad9aa | 82 | struct inode *inode = file_inode(file); |
61922694 | 83 | bool shared = false; |
1da177e4 | 84 | int res = -ENOTDIR; |
61922694 AV |
85 | if (file->f_op->iterate_shared) |
86 | shared = true; | |
87 | else if (!file->f_op->iterate) | |
1da177e4 LT |
88 | goto out; |
89 | ||
90 | res = security_file_permission(file, MAY_READ); | |
91 | if (res) | |
92 | goto out; | |
93 | ||
0dc208b5 KT |
94 | if (shared) |
95 | res = down_read_killable(&inode->i_rwsem); | |
96 | else | |
00235411 | 97 | res = down_write_killable(&inode->i_rwsem); |
0dc208b5 KT |
98 | if (res) |
99 | goto out; | |
da784511 | 100 | |
1da177e4 LT |
101 | res = -ENOENT; |
102 | if (!IS_DEADDIR(inode)) { | |
2233f31a | 103 | ctx->pos = file->f_pos; |
61922694 AV |
104 | if (shared) |
105 | res = file->f_op->iterate_shared(file, ctx); | |
106 | else | |
107 | res = file->f_op->iterate(file, ctx); | |
2233f31a | 108 | file->f_pos = ctx->pos; |
d4c7cf6c | 109 | fsnotify_access(file); |
1da177e4 LT |
110 | file_accessed(file); |
111 | } | |
61922694 AV |
112 | if (shared) |
113 | inode_unlock_shared(inode); | |
114 | else | |
115 | inode_unlock(inode); | |
1da177e4 LT |
116 | out: |
117 | return res; | |
118 | } | |
5c0ba4e0 | 119 | EXPORT_SYMBOL(iterate_dir); |
1da177e4 | 120 | |
8a23eb80 LT |
121 | /* |
122 | * POSIX says that a dirent name cannot contain NULL or a '/'. | |
123 | * | |
124 | * It's not 100% clear what we should really do in this case. | |
125 | * The filesystem is clearly corrupted, but returning a hard | |
126 | * error means that you now don't see any of the other names | |
127 | * either, so that isn't a perfect alternative. | |
128 | * | |
129 | * And if you return an error, what error do you use? Several | |
130 | * filesystems seem to have decided on EUCLEAN being the error | |
131 | * code for EFSCORRUPTED, and that may be the error to use. Or | |
132 | * just EIO, which is perhaps more obvious to users. | |
133 | * | |
134 | * In order to see the other file names in the directory, the | |
135 | * caller might want to make this a "soft" error: skip the | |
136 | * entry, and return the error at the end instead. | |
137 | * | |
138 | * Note that this should likely do a "memchr(name, 0, len)" | |
139 | * check too, since that would be filesystem corruption as | |
140 | * well. However, that case can't actually confuse user space, | |
141 | * which has to do a strlen() on the name anyway to find the | |
142 | * filename length, and the above "soft error" worry means | |
143 | * that it's probably better left alone until we have that | |
144 | * issue clarified. | |
145 | */ | |
146 | static int verify_dirent_name(const char *name, int len) | |
147 | { | |
148 | if (WARN_ON_ONCE(!len)) | |
149 | return -EIO; | |
150 | if (WARN_ON_ONCE(memchr(name, '/', len))) | |
151 | return -EIO; | |
152 | return 0; | |
153 | } | |
154 | ||
1da177e4 LT |
155 | /* |
156 | * Traditional linux readdir() handling.. | |
157 | * | |
158 | * "count=1" is a special case, meaning that the buffer is one | |
159 | * dirent-structure in size and that the code can't handle more | |
160 | * anyway. Thus the special "fillonedir()" function for that | |
161 | * case (the low-level handlers don't need to care about this). | |
162 | */ | |
1da177e4 LT |
163 | |
164 | #ifdef __ARCH_WANT_OLD_READDIR | |
165 | ||
166 | struct old_linux_dirent { | |
167 | unsigned long d_ino; | |
168 | unsigned long d_offset; | |
169 | unsigned short d_namlen; | |
170 | char d_name[1]; | |
171 | }; | |
172 | ||
173 | struct readdir_callback { | |
5c0ba4e0 | 174 | struct dir_context ctx; |
1da177e4 LT |
175 | struct old_linux_dirent __user * dirent; |
176 | int result; | |
177 | }; | |
178 | ||
ac7576f4 MS |
179 | static int fillonedir(struct dir_context *ctx, const char *name, int namlen, |
180 | loff_t offset, u64 ino, unsigned int d_type) | |
1da177e4 | 181 | { |
ac7576f4 MS |
182 | struct readdir_callback *buf = |
183 | container_of(ctx, struct readdir_callback, ctx); | |
1da177e4 | 184 | struct old_linux_dirent __user * dirent; |
afefdbb2 | 185 | unsigned long d_ino; |
1da177e4 LT |
186 | |
187 | if (buf->result) | |
188 | return -EINVAL; | |
afefdbb2 | 189 | d_ino = ino; |
8f3f655d AV |
190 | if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) { |
191 | buf->result = -EOVERFLOW; | |
afefdbb2 | 192 | return -EOVERFLOW; |
8f3f655d | 193 | } |
1da177e4 LT |
194 | buf->result++; |
195 | dirent = buf->dirent; | |
96d4f267 | 196 | if (!access_ok(dirent, |
1da177e4 LT |
197 | (unsigned long)(dirent->d_name + namlen + 1) - |
198 | (unsigned long)dirent)) | |
199 | goto efault; | |
afefdbb2 | 200 | if ( __put_user(d_ino, &dirent->d_ino) || |
1da177e4 LT |
201 | __put_user(offset, &dirent->d_offset) || |
202 | __put_user(namlen, &dirent->d_namlen) || | |
203 | __copy_to_user(dirent->d_name, name, namlen) || | |
204 | __put_user(0, dirent->d_name + namlen)) | |
205 | goto efault; | |
206 | return 0; | |
207 | efault: | |
208 | buf->result = -EFAULT; | |
209 | return -EFAULT; | |
210 | } | |
211 | ||
d4e82042 HC |
212 | SYSCALL_DEFINE3(old_readdir, unsigned int, fd, |
213 | struct old_linux_dirent __user *, dirent, unsigned int, count) | |
1da177e4 LT |
214 | { |
215 | int error; | |
63b6df14 | 216 | struct fd f = fdget_pos(fd); |
ac6614b7 AV |
217 | struct readdir_callback buf = { |
218 | .ctx.actor = fillonedir, | |
219 | .dirent = dirent | |
220 | }; | |
1da177e4 | 221 | |
2903ff01 | 222 | if (!f.file) |
863ced7f | 223 | return -EBADF; |
1da177e4 | 224 | |
5c0ba4e0 | 225 | error = iterate_dir(f.file, &buf.ctx); |
53c9c5c0 | 226 | if (buf.result) |
1da177e4 LT |
227 | error = buf.result; |
228 | ||
63b6df14 | 229 | fdput_pos(f); |
1da177e4 LT |
230 | return error; |
231 | } | |
232 | ||
233 | #endif /* __ARCH_WANT_OLD_READDIR */ | |
234 | ||
235 | /* | |
236 | * New, all-improved, singing, dancing, iBCS2-compliant getdents() | |
237 | * interface. | |
238 | */ | |
239 | struct linux_dirent { | |
240 | unsigned long d_ino; | |
241 | unsigned long d_off; | |
242 | unsigned short d_reclen; | |
243 | char d_name[1]; | |
244 | }; | |
245 | ||
246 | struct getdents_callback { | |
5c0ba4e0 | 247 | struct dir_context ctx; |
1da177e4 LT |
248 | struct linux_dirent __user * current_dir; |
249 | struct linux_dirent __user * previous; | |
250 | int count; | |
251 | int error; | |
252 | }; | |
253 | ||
ac7576f4 MS |
254 | static int filldir(struct dir_context *ctx, const char *name, int namlen, |
255 | loff_t offset, u64 ino, unsigned int d_type) | |
1da177e4 LT |
256 | { |
257 | struct linux_dirent __user * dirent; | |
ac7576f4 MS |
258 | struct getdents_callback *buf = |
259 | container_of(ctx, struct getdents_callback, ctx); | |
afefdbb2 | 260 | unsigned long d_ino; |
85c9fe8f KW |
261 | int reclen = ALIGN(offsetof(struct linux_dirent, d_name) + namlen + 2, |
262 | sizeof(long)); | |
1da177e4 | 263 | |
8a23eb80 LT |
264 | buf->error = verify_dirent_name(name, namlen); |
265 | if (unlikely(buf->error)) | |
266 | return buf->error; | |
1da177e4 LT |
267 | buf->error = -EINVAL; /* only used if we fail.. */ |
268 | if (reclen > buf->count) | |
269 | return -EINVAL; | |
afefdbb2 | 270 | d_ino = ino; |
8f3f655d AV |
271 | if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) { |
272 | buf->error = -EOVERFLOW; | |
afefdbb2 | 273 | return -EOVERFLOW; |
8f3f655d | 274 | } |
1da177e4 | 275 | dirent = buf->previous; |
9f79b78e LT |
276 | if (dirent && signal_pending(current)) |
277 | return -EINTR; | |
278 | ||
279 | /* | |
280 | * Note! This range-checks 'previous' (which may be NULL). | |
281 | * The real range was checked in getdents | |
282 | */ | |
283 | if (!user_access_begin(dirent, sizeof(*dirent))) | |
1da177e4 | 284 | goto efault; |
9f79b78e LT |
285 | if (dirent) |
286 | unsafe_put_user(offset, &dirent->d_off, efault_end); | |
287 | dirent = buf->current_dir; | |
288 | unsafe_put_user(d_ino, &dirent->d_ino, efault_end); | |
289 | unsafe_put_user(reclen, &dirent->d_reclen, efault_end); | |
290 | unsafe_put_user(d_type, (char __user *) dirent + reclen - 1, efault_end); | |
291 | unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end); | |
292 | user_access_end(); | |
293 | ||
1da177e4 LT |
294 | buf->previous = dirent; |
295 | dirent = (void __user *)dirent + reclen; | |
296 | buf->current_dir = dirent; | |
297 | buf->count -= reclen; | |
298 | return 0; | |
9f79b78e LT |
299 | efault_end: |
300 | user_access_end(); | |
1da177e4 LT |
301 | efault: |
302 | buf->error = -EFAULT; | |
303 | return -EFAULT; | |
304 | } | |
305 | ||
20f37034 HC |
306 | SYSCALL_DEFINE3(getdents, unsigned int, fd, |
307 | struct linux_dirent __user *, dirent, unsigned int, count) | |
1da177e4 | 308 | { |
2903ff01 | 309 | struct fd f; |
1da177e4 | 310 | struct linux_dirent __user * lastdirent; |
ac6614b7 AV |
311 | struct getdents_callback buf = { |
312 | .ctx.actor = filldir, | |
313 | .count = count, | |
314 | .current_dir = dirent | |
315 | }; | |
1da177e4 LT |
316 | int error; |
317 | ||
96d4f267 | 318 | if (!access_ok(dirent, count)) |
863ced7f | 319 | return -EFAULT; |
1da177e4 | 320 | |
63b6df14 | 321 | f = fdget_pos(fd); |
2903ff01 | 322 | if (!f.file) |
863ced7f | 323 | return -EBADF; |
1da177e4 | 324 | |
5c0ba4e0 | 325 | error = iterate_dir(f.file, &buf.ctx); |
53c9c5c0 AV |
326 | if (error >= 0) |
327 | error = buf.error; | |
1da177e4 LT |
328 | lastdirent = buf.previous; |
329 | if (lastdirent) { | |
bb6f619b | 330 | if (put_user(buf.ctx.pos, &lastdirent->d_off)) |
1da177e4 LT |
331 | error = -EFAULT; |
332 | else | |
333 | error = count - buf.count; | |
334 | } | |
63b6df14 | 335 | fdput_pos(f); |
1da177e4 LT |
336 | return error; |
337 | } | |
338 | ||
1da177e4 | 339 | struct getdents_callback64 { |
5c0ba4e0 | 340 | struct dir_context ctx; |
1da177e4 LT |
341 | struct linux_dirent64 __user * current_dir; |
342 | struct linux_dirent64 __user * previous; | |
343 | int count; | |
344 | int error; | |
345 | }; | |
346 | ||
ac7576f4 MS |
347 | static int filldir64(struct dir_context *ctx, const char *name, int namlen, |
348 | loff_t offset, u64 ino, unsigned int d_type) | |
1da177e4 LT |
349 | { |
350 | struct linux_dirent64 __user *dirent; | |
ac7576f4 MS |
351 | struct getdents_callback64 *buf = |
352 | container_of(ctx, struct getdents_callback64, ctx); | |
85c9fe8f KW |
353 | int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1, |
354 | sizeof(u64)); | |
1da177e4 | 355 | |
8a23eb80 LT |
356 | buf->error = verify_dirent_name(name, namlen); |
357 | if (unlikely(buf->error)) | |
358 | return buf->error; | |
1da177e4 LT |
359 | buf->error = -EINVAL; /* only used if we fail.. */ |
360 | if (reclen > buf->count) | |
361 | return -EINVAL; | |
362 | dirent = buf->previous; | |
9f79b78e LT |
363 | if (dirent && signal_pending(current)) |
364 | return -EINTR; | |
365 | ||
366 | /* | |
367 | * Note! This range-checks 'previous' (which may be NULL). | |
368 | * The real range was checked in getdents | |
369 | */ | |
370 | if (!user_access_begin(dirent, sizeof(*dirent))) | |
1da177e4 | 371 | goto efault; |
9f79b78e LT |
372 | if (dirent) |
373 | unsafe_put_user(offset, &dirent->d_off, efault_end); | |
374 | dirent = buf->current_dir; | |
375 | unsafe_put_user(ino, &dirent->d_ino, efault_end); | |
376 | unsafe_put_user(reclen, &dirent->d_reclen, efault_end); | |
377 | unsafe_put_user(d_type, &dirent->d_type, efault_end); | |
378 | unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end); | |
379 | user_access_end(); | |
380 | ||
1da177e4 LT |
381 | buf->previous = dirent; |
382 | dirent = (void __user *)dirent + reclen; | |
383 | buf->current_dir = dirent; | |
384 | buf->count -= reclen; | |
385 | return 0; | |
9f79b78e LT |
386 | efault_end: |
387 | user_access_end(); | |
1da177e4 LT |
388 | efault: |
389 | buf->error = -EFAULT; | |
390 | return -EFAULT; | |
391 | } | |
392 | ||
454dab3f DB |
393 | int ksys_getdents64(unsigned int fd, struct linux_dirent64 __user *dirent, |
394 | unsigned int count) | |
1da177e4 | 395 | { |
2903ff01 | 396 | struct fd f; |
1da177e4 | 397 | struct linux_dirent64 __user * lastdirent; |
ac6614b7 AV |
398 | struct getdents_callback64 buf = { |
399 | .ctx.actor = filldir64, | |
400 | .count = count, | |
401 | .current_dir = dirent | |
402 | }; | |
1da177e4 LT |
403 | int error; |
404 | ||
96d4f267 | 405 | if (!access_ok(dirent, count)) |
863ced7f | 406 | return -EFAULT; |
1da177e4 | 407 | |
63b6df14 | 408 | f = fdget_pos(fd); |
2903ff01 | 409 | if (!f.file) |
863ced7f | 410 | return -EBADF; |
1da177e4 | 411 | |
5c0ba4e0 | 412 | error = iterate_dir(f.file, &buf.ctx); |
53c9c5c0 AV |
413 | if (error >= 0) |
414 | error = buf.error; | |
1da177e4 LT |
415 | lastdirent = buf.previous; |
416 | if (lastdirent) { | |
bb6f619b | 417 | typeof(lastdirent->d_off) d_off = buf.ctx.pos; |
1da177e4 | 418 | if (__put_user(d_off, &lastdirent->d_off)) |
53c9c5c0 AV |
419 | error = -EFAULT; |
420 | else | |
421 | error = count - buf.count; | |
1da177e4 | 422 | } |
63b6df14 | 423 | fdput_pos(f); |
1da177e4 LT |
424 | return error; |
425 | } | |
0460b2a2 | 426 | |
454dab3f DB |
427 | |
428 | SYSCALL_DEFINE3(getdents64, unsigned int, fd, | |
429 | struct linux_dirent64 __user *, dirent, unsigned int, count) | |
430 | { | |
431 | return ksys_getdents64(fd, dirent, count); | |
432 | } | |
433 | ||
0460b2a2 AV |
434 | #ifdef CONFIG_COMPAT |
435 | struct compat_old_linux_dirent { | |
436 | compat_ulong_t d_ino; | |
437 | compat_ulong_t d_offset; | |
438 | unsigned short d_namlen; | |
439 | char d_name[1]; | |
440 | }; | |
441 | ||
442 | struct compat_readdir_callback { | |
443 | struct dir_context ctx; | |
444 | struct compat_old_linux_dirent __user *dirent; | |
445 | int result; | |
446 | }; | |
447 | ||
448 | static int compat_fillonedir(struct dir_context *ctx, const char *name, | |
449 | int namlen, loff_t offset, u64 ino, | |
450 | unsigned int d_type) | |
451 | { | |
452 | struct compat_readdir_callback *buf = | |
453 | container_of(ctx, struct compat_readdir_callback, ctx); | |
454 | struct compat_old_linux_dirent __user *dirent; | |
455 | compat_ulong_t d_ino; | |
456 | ||
457 | if (buf->result) | |
458 | return -EINVAL; | |
459 | d_ino = ino; | |
460 | if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) { | |
461 | buf->result = -EOVERFLOW; | |
462 | return -EOVERFLOW; | |
463 | } | |
464 | buf->result++; | |
465 | dirent = buf->dirent; | |
96d4f267 | 466 | if (!access_ok(dirent, |
0460b2a2 AV |
467 | (unsigned long)(dirent->d_name + namlen + 1) - |
468 | (unsigned long)dirent)) | |
469 | goto efault; | |
470 | if ( __put_user(d_ino, &dirent->d_ino) || | |
471 | __put_user(offset, &dirent->d_offset) || | |
472 | __put_user(namlen, &dirent->d_namlen) || | |
473 | __copy_to_user(dirent->d_name, name, namlen) || | |
474 | __put_user(0, dirent->d_name + namlen)) | |
475 | goto efault; | |
476 | return 0; | |
477 | efault: | |
478 | buf->result = -EFAULT; | |
479 | return -EFAULT; | |
480 | } | |
481 | ||
482 | COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd, | |
483 | struct compat_old_linux_dirent __user *, dirent, unsigned int, count) | |
484 | { | |
485 | int error; | |
486 | struct fd f = fdget_pos(fd); | |
487 | struct compat_readdir_callback buf = { | |
488 | .ctx.actor = compat_fillonedir, | |
489 | .dirent = dirent | |
490 | }; | |
491 | ||
492 | if (!f.file) | |
493 | return -EBADF; | |
494 | ||
495 | error = iterate_dir(f.file, &buf.ctx); | |
496 | if (buf.result) | |
497 | error = buf.result; | |
498 | ||
499 | fdput_pos(f); | |
500 | return error; | |
501 | } | |
502 | ||
503 | struct compat_linux_dirent { | |
504 | compat_ulong_t d_ino; | |
505 | compat_ulong_t d_off; | |
506 | unsigned short d_reclen; | |
507 | char d_name[1]; | |
508 | }; | |
509 | ||
510 | struct compat_getdents_callback { | |
511 | struct dir_context ctx; | |
512 | struct compat_linux_dirent __user *current_dir; | |
513 | struct compat_linux_dirent __user *previous; | |
514 | int count; | |
515 | int error; | |
516 | }; | |
517 | ||
518 | static int compat_filldir(struct dir_context *ctx, const char *name, int namlen, | |
519 | loff_t offset, u64 ino, unsigned int d_type) | |
520 | { | |
521 | struct compat_linux_dirent __user * dirent; | |
522 | struct compat_getdents_callback *buf = | |
523 | container_of(ctx, struct compat_getdents_callback, ctx); | |
524 | compat_ulong_t d_ino; | |
525 | int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) + | |
526 | namlen + 2, sizeof(compat_long_t)); | |
527 | ||
528 | buf->error = -EINVAL; /* only used if we fail.. */ | |
529 | if (reclen > buf->count) | |
530 | return -EINVAL; | |
531 | d_ino = ino; | |
532 | if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) { | |
533 | buf->error = -EOVERFLOW; | |
534 | return -EOVERFLOW; | |
535 | } | |
536 | dirent = buf->previous; | |
537 | if (dirent) { | |
538 | if (signal_pending(current)) | |
539 | return -EINTR; | |
540 | if (__put_user(offset, &dirent->d_off)) | |
541 | goto efault; | |
542 | } | |
543 | dirent = buf->current_dir; | |
544 | if (__put_user(d_ino, &dirent->d_ino)) | |
545 | goto efault; | |
546 | if (__put_user(reclen, &dirent->d_reclen)) | |
547 | goto efault; | |
548 | if (copy_to_user(dirent->d_name, name, namlen)) | |
549 | goto efault; | |
550 | if (__put_user(0, dirent->d_name + namlen)) | |
551 | goto efault; | |
552 | if (__put_user(d_type, (char __user *) dirent + reclen - 1)) | |
553 | goto efault; | |
554 | buf->previous = dirent; | |
555 | dirent = (void __user *)dirent + reclen; | |
556 | buf->current_dir = dirent; | |
557 | buf->count -= reclen; | |
558 | return 0; | |
559 | efault: | |
560 | buf->error = -EFAULT; | |
561 | return -EFAULT; | |
562 | } | |
563 | ||
564 | COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, | |
565 | struct compat_linux_dirent __user *, dirent, unsigned int, count) | |
566 | { | |
567 | struct fd f; | |
568 | struct compat_linux_dirent __user * lastdirent; | |
569 | struct compat_getdents_callback buf = { | |
570 | .ctx.actor = compat_filldir, | |
571 | .current_dir = dirent, | |
572 | .count = count | |
573 | }; | |
574 | int error; | |
575 | ||
96d4f267 | 576 | if (!access_ok(dirent, count)) |
0460b2a2 AV |
577 | return -EFAULT; |
578 | ||
579 | f = fdget_pos(fd); | |
580 | if (!f.file) | |
581 | return -EBADF; | |
582 | ||
583 | error = iterate_dir(f.file, &buf.ctx); | |
584 | if (error >= 0) | |
585 | error = buf.error; | |
586 | lastdirent = buf.previous; | |
587 | if (lastdirent) { | |
588 | if (put_user(buf.ctx.pos, &lastdirent->d_off)) | |
589 | error = -EFAULT; | |
590 | else | |
591 | error = count - buf.count; | |
592 | } | |
593 | fdput_pos(f); | |
594 | return error; | |
595 | } | |
596 | #endif |