xref: /linux/fs/stat.c (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/stat.c
4  *
5  *  Copyright (C) 1991, 1992  Linus Torvalds
6  */
7 
8 #include <linux/export.h>
9 #include <linux/mm.h>
10 #include <linux/errno.h>
11 #include <linux/file.h>
12 #include <linux/highuid.h>
13 #include <linux/fs.h>
14 #include <linux/namei.h>
15 #include <linux/security.h>
16 #include <linux/cred.h>
17 #include <linux/syscalls.h>
18 #include <linux/pagemap.h>
19 #include <linux/compat.h>
20 
21 #include <linux/uaccess.h>
22 #include <asm/unistd.h>
23 
24 #include "internal.h"
25 #include "mount.h"
26 
27 /**
28  * generic_fillattr - Fill in the basic attributes from the inode struct
29  * @inode: Inode to use as the source
30  * @stat: Where to fill in the attributes
31  *
32  * Fill in the basic attributes in the kstat structure from data that's to be
33  * found on the VFS inode structure.  This is the default if no getattr inode
34  * operation is supplied.
35  */
36 void generic_fillattr(struct inode *inode, struct kstat *stat)
37 {
38 	stat->dev = inode->i_sb->s_dev;
39 	stat->ino = inode->i_ino;
40 	stat->mode = inode->i_mode;
41 	stat->nlink = inode->i_nlink;
42 	stat->uid = inode->i_uid;
43 	stat->gid = inode->i_gid;
44 	stat->rdev = inode->i_rdev;
45 	stat->size = i_size_read(inode);
46 	stat->atime = inode->i_atime;
47 	stat->mtime = inode->i_mtime;
48 	stat->ctime = inode->i_ctime;
49 	stat->blksize = i_blocksize(inode);
50 	stat->blocks = inode->i_blocks;
51 }
52 EXPORT_SYMBOL(generic_fillattr);
53 
54 /**
55  * vfs_getattr_nosec - getattr without security checks
56  * @path: file to get attributes from
57  * @stat: structure to return attributes in
58  * @request_mask: STATX_xxx flags indicating what the caller wants
59  * @query_flags: Query mode (AT_STATX_SYNC_TYPE)
60  *
61  * Get attributes without calling security_inode_getattr.
62  *
63  * Currently the only caller other than vfs_getattr is internal to the
64  * filehandle lookup code, which uses only the inode number and returns no
65  * attributes to any user.  Any other code probably wants vfs_getattr.
66  */
67 int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
68 		      u32 request_mask, unsigned int query_flags)
69 {
70 	struct inode *inode = d_backing_inode(path->dentry);
71 
72 	memset(stat, 0, sizeof(*stat));
73 	stat->result_mask |= STATX_BASIC_STATS;
74 	query_flags &= AT_STATX_SYNC_TYPE;
75 
76 	/* allow the fs to override these if it really wants to */
77 	/* SB_NOATIME means filesystem supplies dummy atime value */
78 	if (inode->i_sb->s_flags & SB_NOATIME)
79 		stat->result_mask &= ~STATX_ATIME;
80 	if (IS_AUTOMOUNT(inode))
81 		stat->attributes |= STATX_ATTR_AUTOMOUNT;
82 
83 	if (IS_DAX(inode))
84 		stat->attributes |= STATX_ATTR_DAX;
85 
86 	if (inode->i_op->getattr)
87 		return inode->i_op->getattr(path, stat, request_mask,
88 					    query_flags);
89 
90 	generic_fillattr(inode, stat);
91 	return 0;
92 }
93 EXPORT_SYMBOL(vfs_getattr_nosec);
94 
95 /*
96  * vfs_getattr - Get the enhanced basic attributes of a file
97  * @path: The file of interest
98  * @stat: Where to return the statistics
99  * @request_mask: STATX_xxx flags indicating what the caller wants
100  * @query_flags: Query mode (AT_STATX_SYNC_TYPE)
101  *
102  * Ask the filesystem for a file's attributes.  The caller must indicate in
103  * request_mask and query_flags to indicate what they want.
104  *
105  * If the file is remote, the filesystem can be forced to update the attributes
106  * from the backing store by passing AT_STATX_FORCE_SYNC in query_flags or can
107  * suppress the update by passing AT_STATX_DONT_SYNC.
108  *
109  * Bits must have been set in request_mask to indicate which attributes the
110  * caller wants retrieving.  Any such attribute not requested may be returned
111  * anyway, but the value may be approximate, and, if remote, may not have been
112  * synchronised with the server.
113  *
114  * 0 will be returned on success, and a -ve error code if unsuccessful.
115  */
116 int vfs_getattr(const struct path *path, struct kstat *stat,
117 		u32 request_mask, unsigned int query_flags)
118 {
119 	int retval;
120 
121 	retval = security_inode_getattr(path);
122 	if (retval)
123 		return retval;
124 	return vfs_getattr_nosec(path, stat, request_mask, query_flags);
125 }
126 EXPORT_SYMBOL(vfs_getattr);
127 
128 /**
129  * vfs_fstat - Get the basic attributes by file descriptor
130  * @fd: The file descriptor referring to the file of interest
131  * @stat: The result structure to fill in.
132  *
133  * This function is a wrapper around vfs_getattr().  The main difference is
134  * that it uses a file descriptor to determine the file location.
135  *
136  * 0 will be returned on success, and a -ve error code if unsuccessful.
137  */
138 int vfs_fstat(int fd, struct kstat *stat)
139 {
140 	struct fd f;
141 	int error;
142 
143 	f = fdget_raw(fd);
144 	if (!f.file)
145 		return -EBADF;
146 	error = vfs_getattr(&f.file->f_path, stat, STATX_BASIC_STATS, 0);
147 	fdput(f);
148 	return error;
149 }
150 
151 /**
152  * vfs_statx - Get basic and extra attributes by filename
153  * @dfd: A file descriptor representing the base dir for a relative filename
154  * @filename: The name of the file of interest
155  * @flags: Flags to control the query
156  * @stat: The result structure to fill in.
157  * @request_mask: STATX_xxx flags indicating what the caller wants
158  *
159  * This function is a wrapper around vfs_getattr().  The main difference is
160  * that it uses a filename and base directory to determine the file location.
161  * Additionally, the use of AT_SYMLINK_NOFOLLOW in flags will prevent a symlink
162  * at the given name from being referenced.
163  *
164  * 0 will be returned on success, and a -ve error code if unsuccessful.
165  */
166 static int vfs_statx(int dfd, const char __user *filename, int flags,
167 	      struct kstat *stat, u32 request_mask)
168 {
169 	struct path path;
170 	unsigned lookup_flags = 0;
171 	int error;
172 
173 	if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT | AT_EMPTY_PATH |
174 		      AT_STATX_SYNC_TYPE))
175 		return -EINVAL;
176 
177 	if (!(flags & AT_SYMLINK_NOFOLLOW))
178 		lookup_flags |= LOOKUP_FOLLOW;
179 	if (!(flags & AT_NO_AUTOMOUNT))
180 		lookup_flags |= LOOKUP_AUTOMOUNT;
181 	if (flags & AT_EMPTY_PATH)
182 		lookup_flags |= LOOKUP_EMPTY;
183 
184 retry:
185 	error = user_path_at(dfd, filename, lookup_flags, &path);
186 	if (error)
187 		goto out;
188 
189 	error = vfs_getattr(&path, stat, request_mask, flags);
190 	stat->mnt_id = real_mount(path.mnt)->mnt_id;
191 	stat->result_mask |= STATX_MNT_ID;
192 	if (path.mnt->mnt_root == path.dentry)
193 		stat->attributes |= STATX_ATTR_MOUNT_ROOT;
194 	stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT;
195 	path_put(&path);
196 	if (retry_estale(error, lookup_flags)) {
197 		lookup_flags |= LOOKUP_REVAL;
198 		goto retry;
199 	}
200 out:
201 	return error;
202 }
203 
204 int vfs_fstatat(int dfd, const char __user *filename,
205 			      struct kstat *stat, int flags)
206 {
207 	return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
208 			 stat, STATX_BASIC_STATS);
209 }
210 
211 #ifdef __ARCH_WANT_OLD_STAT
212 
213 /*
214  * For backward compatibility?  Maybe this should be moved
215  * into arch/i386 instead?
216  */
217 static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
218 {
219 	static int warncount = 5;
220 	struct __old_kernel_stat tmp;
221 
222 	if (warncount > 0) {
223 		warncount--;
224 		printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
225 			current->comm);
226 	} else if (warncount < 0) {
227 		/* it's laughable, but... */
228 		warncount = 0;
229 	}
230 
231 	memset(&tmp, 0, sizeof(struct __old_kernel_stat));
232 	tmp.st_dev = old_encode_dev(stat->dev);
233 	tmp.st_ino = stat->ino;
234 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
235 		return -EOVERFLOW;
236 	tmp.st_mode = stat->mode;
237 	tmp.st_nlink = stat->nlink;
238 	if (tmp.st_nlink != stat->nlink)
239 		return -EOVERFLOW;
240 	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
241 	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
242 	tmp.st_rdev = old_encode_dev(stat->rdev);
243 #if BITS_PER_LONG == 32
244 	if (stat->size > MAX_NON_LFS)
245 		return -EOVERFLOW;
246 #endif
247 	tmp.st_size = stat->size;
248 	tmp.st_atime = stat->atime.tv_sec;
249 	tmp.st_mtime = stat->mtime.tv_sec;
250 	tmp.st_ctime = stat->ctime.tv_sec;
251 	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
252 }
253 
254 SYSCALL_DEFINE2(stat, const char __user *, filename,
255 		struct __old_kernel_stat __user *, statbuf)
256 {
257 	struct kstat stat;
258 	int error;
259 
260 	error = vfs_stat(filename, &stat);
261 	if (error)
262 		return error;
263 
264 	return cp_old_stat(&stat, statbuf);
265 }
266 
267 SYSCALL_DEFINE2(lstat, const char __user *, filename,
268 		struct __old_kernel_stat __user *, statbuf)
269 {
270 	struct kstat stat;
271 	int error;
272 
273 	error = vfs_lstat(filename, &stat);
274 	if (error)
275 		return error;
276 
277 	return cp_old_stat(&stat, statbuf);
278 }
279 
280 SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
281 {
282 	struct kstat stat;
283 	int error = vfs_fstat(fd, &stat);
284 
285 	if (!error)
286 		error = cp_old_stat(&stat, statbuf);
287 
288 	return error;
289 }
290 
291 #endif /* __ARCH_WANT_OLD_STAT */
292 
293 #ifdef __ARCH_WANT_NEW_STAT
294 
295 #if BITS_PER_LONG == 32
296 #  define choose_32_64(a,b) a
297 #else
298 #  define choose_32_64(a,b) b
299 #endif
300 
301 #define valid_dev(x)  choose_32_64(old_valid_dev(x),true)
302 #define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
303 
304 #ifndef INIT_STRUCT_STAT_PADDING
305 #  define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
306 #endif
307 
308 static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
309 {
310 	struct stat tmp;
311 
312 	if (!valid_dev(stat->dev) || !valid_dev(stat->rdev))
313 		return -EOVERFLOW;
314 #if BITS_PER_LONG == 32
315 	if (stat->size > MAX_NON_LFS)
316 		return -EOVERFLOW;
317 #endif
318 
319 	INIT_STRUCT_STAT_PADDING(tmp);
320 	tmp.st_dev = encode_dev(stat->dev);
321 	tmp.st_ino = stat->ino;
322 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
323 		return -EOVERFLOW;
324 	tmp.st_mode = stat->mode;
325 	tmp.st_nlink = stat->nlink;
326 	if (tmp.st_nlink != stat->nlink)
327 		return -EOVERFLOW;
328 	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
329 	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
330 	tmp.st_rdev = encode_dev(stat->rdev);
331 	tmp.st_size = stat->size;
332 	tmp.st_atime = stat->atime.tv_sec;
333 	tmp.st_mtime = stat->mtime.tv_sec;
334 	tmp.st_ctime = stat->ctime.tv_sec;
335 #ifdef STAT_HAVE_NSEC
336 	tmp.st_atime_nsec = stat->atime.tv_nsec;
337 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
338 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
339 #endif
340 	tmp.st_blocks = stat->blocks;
341 	tmp.st_blksize = stat->blksize;
342 	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
343 }
344 
345 SYSCALL_DEFINE2(newstat, const char __user *, filename,
346 		struct stat __user *, statbuf)
347 {
348 	struct kstat stat;
349 	int error = vfs_stat(filename, &stat);
350 
351 	if (error)
352 		return error;
353 	return cp_new_stat(&stat, statbuf);
354 }
355 
356 SYSCALL_DEFINE2(newlstat, const char __user *, filename,
357 		struct stat __user *, statbuf)
358 {
359 	struct kstat stat;
360 	int error;
361 
362 	error = vfs_lstat(filename, &stat);
363 	if (error)
364 		return error;
365 
366 	return cp_new_stat(&stat, statbuf);
367 }
368 
369 #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
370 SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
371 		struct stat __user *, statbuf, int, flag)
372 {
373 	struct kstat stat;
374 	int error;
375 
376 	error = vfs_fstatat(dfd, filename, &stat, flag);
377 	if (error)
378 		return error;
379 	return cp_new_stat(&stat, statbuf);
380 }
381 #endif
382 
383 SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
384 {
385 	struct kstat stat;
386 	int error = vfs_fstat(fd, &stat);
387 
388 	if (!error)
389 		error = cp_new_stat(&stat, statbuf);
390 
391 	return error;
392 }
393 #endif
394 
395 static int do_readlinkat(int dfd, const char __user *pathname,
396 			 char __user *buf, int bufsiz)
397 {
398 	struct path path;
399 	int error;
400 	int empty = 0;
401 	unsigned int lookup_flags = LOOKUP_EMPTY;
402 
403 	if (bufsiz <= 0)
404 		return -EINVAL;
405 
406 retry:
407 	error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
408 	if (!error) {
409 		struct inode *inode = d_backing_inode(path.dentry);
410 
411 		error = empty ? -ENOENT : -EINVAL;
412 		/*
413 		 * AFS mountpoints allow readlink(2) but are not symlinks
414 		 */
415 		if (d_is_symlink(path.dentry) || inode->i_op->readlink) {
416 			error = security_inode_readlink(path.dentry);
417 			if (!error) {
418 				touch_atime(&path);
419 				error = vfs_readlink(path.dentry, buf, bufsiz);
420 			}
421 		}
422 		path_put(&path);
423 		if (retry_estale(error, lookup_flags)) {
424 			lookup_flags |= LOOKUP_REVAL;
425 			goto retry;
426 		}
427 	}
428 	return error;
429 }
430 
431 SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
432 		char __user *, buf, int, bufsiz)
433 {
434 	return do_readlinkat(dfd, pathname, buf, bufsiz);
435 }
436 
437 SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
438 		int, bufsiz)
439 {
440 	return do_readlinkat(AT_FDCWD, path, buf, bufsiz);
441 }
442 
443 
444 /* ---------- LFS-64 ----------- */
445 #if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
446 
447 #ifndef INIT_STRUCT_STAT64_PADDING
448 #  define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
449 #endif
450 
451 static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
452 {
453 	struct stat64 tmp;
454 
455 	INIT_STRUCT_STAT64_PADDING(tmp);
456 #ifdef CONFIG_MIPS
457 	/* mips has weird padding, so we don't get 64 bits there */
458 	tmp.st_dev = new_encode_dev(stat->dev);
459 	tmp.st_rdev = new_encode_dev(stat->rdev);
460 #else
461 	tmp.st_dev = huge_encode_dev(stat->dev);
462 	tmp.st_rdev = huge_encode_dev(stat->rdev);
463 #endif
464 	tmp.st_ino = stat->ino;
465 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
466 		return -EOVERFLOW;
467 #ifdef STAT64_HAS_BROKEN_ST_INO
468 	tmp.__st_ino = stat->ino;
469 #endif
470 	tmp.st_mode = stat->mode;
471 	tmp.st_nlink = stat->nlink;
472 	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
473 	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
474 	tmp.st_atime = stat->atime.tv_sec;
475 	tmp.st_atime_nsec = stat->atime.tv_nsec;
476 	tmp.st_mtime = stat->mtime.tv_sec;
477 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
478 	tmp.st_ctime = stat->ctime.tv_sec;
479 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
480 	tmp.st_size = stat->size;
481 	tmp.st_blocks = stat->blocks;
482 	tmp.st_blksize = stat->blksize;
483 	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
484 }
485 
486 SYSCALL_DEFINE2(stat64, const char __user *, filename,
487 		struct stat64 __user *, statbuf)
488 {
489 	struct kstat stat;
490 	int error = vfs_stat(filename, &stat);
491 
492 	if (!error)
493 		error = cp_new_stat64(&stat, statbuf);
494 
495 	return error;
496 }
497 
498 SYSCALL_DEFINE2(lstat64, const char __user *, filename,
499 		struct stat64 __user *, statbuf)
500 {
501 	struct kstat stat;
502 	int error = vfs_lstat(filename, &stat);
503 
504 	if (!error)
505 		error = cp_new_stat64(&stat, statbuf);
506 
507 	return error;
508 }
509 
510 SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
511 {
512 	struct kstat stat;
513 	int error = vfs_fstat(fd, &stat);
514 
515 	if (!error)
516 		error = cp_new_stat64(&stat, statbuf);
517 
518 	return error;
519 }
520 
521 SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
522 		struct stat64 __user *, statbuf, int, flag)
523 {
524 	struct kstat stat;
525 	int error;
526 
527 	error = vfs_fstatat(dfd, filename, &stat, flag);
528 	if (error)
529 		return error;
530 	return cp_new_stat64(&stat, statbuf);
531 }
532 #endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
533 
534 static noinline_for_stack int
535 cp_statx(const struct kstat *stat, struct statx __user *buffer)
536 {
537 	struct statx tmp;
538 
539 	memset(&tmp, 0, sizeof(tmp));
540 
541 	tmp.stx_mask = stat->result_mask;
542 	tmp.stx_blksize = stat->blksize;
543 	tmp.stx_attributes = stat->attributes;
544 	tmp.stx_nlink = stat->nlink;
545 	tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid);
546 	tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid);
547 	tmp.stx_mode = stat->mode;
548 	tmp.stx_ino = stat->ino;
549 	tmp.stx_size = stat->size;
550 	tmp.stx_blocks = stat->blocks;
551 	tmp.stx_attributes_mask = stat->attributes_mask;
552 	tmp.stx_atime.tv_sec = stat->atime.tv_sec;
553 	tmp.stx_atime.tv_nsec = stat->atime.tv_nsec;
554 	tmp.stx_btime.tv_sec = stat->btime.tv_sec;
555 	tmp.stx_btime.tv_nsec = stat->btime.tv_nsec;
556 	tmp.stx_ctime.tv_sec = stat->ctime.tv_sec;
557 	tmp.stx_ctime.tv_nsec = stat->ctime.tv_nsec;
558 	tmp.stx_mtime.tv_sec = stat->mtime.tv_sec;
559 	tmp.stx_mtime.tv_nsec = stat->mtime.tv_nsec;
560 	tmp.stx_rdev_major = MAJOR(stat->rdev);
561 	tmp.stx_rdev_minor = MINOR(stat->rdev);
562 	tmp.stx_dev_major = MAJOR(stat->dev);
563 	tmp.stx_dev_minor = MINOR(stat->dev);
564 	tmp.stx_mnt_id = stat->mnt_id;
565 
566 	return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
567 }
568 
569 int do_statx(int dfd, const char __user *filename, unsigned flags,
570 	     unsigned int mask, struct statx __user *buffer)
571 {
572 	struct kstat stat;
573 	int error;
574 
575 	if (mask & STATX__RESERVED)
576 		return -EINVAL;
577 	if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
578 		return -EINVAL;
579 
580 	error = vfs_statx(dfd, filename, flags, &stat, mask);
581 	if (error)
582 		return error;
583 
584 	return cp_statx(&stat, buffer);
585 }
586 
587 /**
588  * sys_statx - System call to get enhanced stats
589  * @dfd: Base directory to pathwalk from *or* fd to stat.
590  * @filename: File to stat or "" with AT_EMPTY_PATH
591  * @flags: AT_* flags to control pathwalk.
592  * @mask: Parts of statx struct actually required.
593  * @buffer: Result buffer.
594  *
595  * Note that fstat() can be emulated by setting dfd to the fd of interest,
596  * supplying "" as the filename and setting AT_EMPTY_PATH in the flags.
597  */
598 SYSCALL_DEFINE5(statx,
599 		int, dfd, const char __user *, filename, unsigned, flags,
600 		unsigned int, mask,
601 		struct statx __user *, buffer)
602 {
603 	return do_statx(dfd, filename, flags, mask, buffer);
604 }
605 
606 #ifdef CONFIG_COMPAT
607 static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
608 {
609 	struct compat_stat tmp;
610 
611 	if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
612 		return -EOVERFLOW;
613 
614 	memset(&tmp, 0, sizeof(tmp));
615 	tmp.st_dev = old_encode_dev(stat->dev);
616 	tmp.st_ino = stat->ino;
617 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
618 		return -EOVERFLOW;
619 	tmp.st_mode = stat->mode;
620 	tmp.st_nlink = stat->nlink;
621 	if (tmp.st_nlink != stat->nlink)
622 		return -EOVERFLOW;
623 	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
624 	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
625 	tmp.st_rdev = old_encode_dev(stat->rdev);
626 	if ((u64) stat->size > MAX_NON_LFS)
627 		return -EOVERFLOW;
628 	tmp.st_size = stat->size;
629 	tmp.st_atime = stat->atime.tv_sec;
630 	tmp.st_atime_nsec = stat->atime.tv_nsec;
631 	tmp.st_mtime = stat->mtime.tv_sec;
632 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
633 	tmp.st_ctime = stat->ctime.tv_sec;
634 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
635 	tmp.st_blocks = stat->blocks;
636 	tmp.st_blksize = stat->blksize;
637 	return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
638 }
639 
640 COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename,
641 		       struct compat_stat __user *, statbuf)
642 {
643 	struct kstat stat;
644 	int error;
645 
646 	error = vfs_stat(filename, &stat);
647 	if (error)
648 		return error;
649 	return cp_compat_stat(&stat, statbuf);
650 }
651 
652 COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename,
653 		       struct compat_stat __user *, statbuf)
654 {
655 	struct kstat stat;
656 	int error;
657 
658 	error = vfs_lstat(filename, &stat);
659 	if (error)
660 		return error;
661 	return cp_compat_stat(&stat, statbuf);
662 }
663 
664 #ifndef __ARCH_WANT_STAT64
665 COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd,
666 		       const char __user *, filename,
667 		       struct compat_stat __user *, statbuf, int, flag)
668 {
669 	struct kstat stat;
670 	int error;
671 
672 	error = vfs_fstatat(dfd, filename, &stat, flag);
673 	if (error)
674 		return error;
675 	return cp_compat_stat(&stat, statbuf);
676 }
677 #endif
678 
679 COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd,
680 		       struct compat_stat __user *, statbuf)
681 {
682 	struct kstat stat;
683 	int error = vfs_fstat(fd, &stat);
684 
685 	if (!error)
686 		error = cp_compat_stat(&stat, statbuf);
687 	return error;
688 }
689 #endif
690 
691 /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
692 void __inode_add_bytes(struct inode *inode, loff_t bytes)
693 {
694 	inode->i_blocks += bytes >> 9;
695 	bytes &= 511;
696 	inode->i_bytes += bytes;
697 	if (inode->i_bytes >= 512) {
698 		inode->i_blocks++;
699 		inode->i_bytes -= 512;
700 	}
701 }
702 EXPORT_SYMBOL(__inode_add_bytes);
703 
704 void inode_add_bytes(struct inode *inode, loff_t bytes)
705 {
706 	spin_lock(&inode->i_lock);
707 	__inode_add_bytes(inode, bytes);
708 	spin_unlock(&inode->i_lock);
709 }
710 
711 EXPORT_SYMBOL(inode_add_bytes);
712 
713 void __inode_sub_bytes(struct inode *inode, loff_t bytes)
714 {
715 	inode->i_blocks -= bytes >> 9;
716 	bytes &= 511;
717 	if (inode->i_bytes < bytes) {
718 		inode->i_blocks--;
719 		inode->i_bytes += 512;
720 	}
721 	inode->i_bytes -= bytes;
722 }
723 
724 EXPORT_SYMBOL(__inode_sub_bytes);
725 
726 void inode_sub_bytes(struct inode *inode, loff_t bytes)
727 {
728 	spin_lock(&inode->i_lock);
729 	__inode_sub_bytes(inode, bytes);
730 	spin_unlock(&inode->i_lock);
731 }
732 
733 EXPORT_SYMBOL(inode_sub_bytes);
734 
735 loff_t inode_get_bytes(struct inode *inode)
736 {
737 	loff_t ret;
738 
739 	spin_lock(&inode->i_lock);
740 	ret = __inode_get_bytes(inode);
741 	spin_unlock(&inode->i_lock);
742 	return ret;
743 }
744 
745 EXPORT_SYMBOL(inode_get_bytes);
746 
747 void inode_set_bytes(struct inode *inode, loff_t bytes)
748 {
749 	/* Caller is here responsible for sufficient locking
750 	 * (ie. inode->i_lock) */
751 	inode->i_blocks = bytes >> 9;
752 	inode->i_bytes = bytes & 511;
753 }
754 
755 EXPORT_SYMBOL(inode_set_bytes);
756