xref: /openbmc/linux/fs/stat.c (revision da9aa5d96bfe49e903ce2bc01cfb8a776c2619e9)
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 (KSTAT_QUERY_FLAGS)
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 &= KSTAT_QUERY_FLAGS;
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 (KSTAT_QUERY_FLAGS)
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 static inline unsigned vfs_stat_set_lookup_flags(unsigned *lookup_flags,
152 						 int flags)
153 {
154 	if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
155 		       AT_EMPTY_PATH | KSTAT_QUERY_FLAGS)) != 0)
156 		return -EINVAL;
157 
158 	*lookup_flags = LOOKUP_FOLLOW | LOOKUP_AUTOMOUNT;
159 	if (flags & AT_SYMLINK_NOFOLLOW)
160 		*lookup_flags &= ~LOOKUP_FOLLOW;
161 	if (flags & AT_NO_AUTOMOUNT)
162 		*lookup_flags &= ~LOOKUP_AUTOMOUNT;
163 	if (flags & AT_EMPTY_PATH)
164 		*lookup_flags |= LOOKUP_EMPTY;
165 
166 	return 0;
167 }
168 
169 /**
170  * vfs_statx - Get basic and extra attributes by filename
171  * @dfd: A file descriptor representing the base dir for a relative filename
172  * @filename: The name of the file of interest
173  * @flags: Flags to control the query
174  * @stat: The result structure to fill in.
175  * @request_mask: STATX_xxx flags indicating what the caller wants
176  *
177  * This function is a wrapper around vfs_getattr().  The main difference is
178  * that it uses a filename and base directory to determine the file location.
179  * Additionally, the use of AT_SYMLINK_NOFOLLOW in flags will prevent a symlink
180  * at the given name from being referenced.
181  *
182  * 0 will be returned on success, and a -ve error code if unsuccessful.
183  */
184 int vfs_statx(int dfd, const char __user *filename, int flags,
185 	      struct kstat *stat, u32 request_mask)
186 {
187 	struct path path;
188 	int error = -EINVAL;
189 	unsigned lookup_flags;
190 
191 	if (vfs_stat_set_lookup_flags(&lookup_flags, flags))
192 		return -EINVAL;
193 retry:
194 	error = user_path_at(dfd, filename, lookup_flags, &path);
195 	if (error)
196 		goto out;
197 
198 	error = vfs_getattr(&path, stat, request_mask, flags);
199 	stat->mnt_id = real_mount(path.mnt)->mnt_id;
200 	stat->result_mask |= STATX_MNT_ID;
201 	if (path.mnt->mnt_root == path.dentry)
202 		stat->attributes |= STATX_ATTR_MOUNT_ROOT;
203 	stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT;
204 	path_put(&path);
205 	if (retry_estale(error, lookup_flags)) {
206 		lookup_flags |= LOOKUP_REVAL;
207 		goto retry;
208 	}
209 out:
210 	return error;
211 }
212 EXPORT_SYMBOL(vfs_statx);
213 
214 
215 #ifdef __ARCH_WANT_OLD_STAT
216 
217 /*
218  * For backward compatibility?  Maybe this should be moved
219  * into arch/i386 instead?
220  */
221 static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
222 {
223 	static int warncount = 5;
224 	struct __old_kernel_stat tmp;
225 
226 	if (warncount > 0) {
227 		warncount--;
228 		printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
229 			current->comm);
230 	} else if (warncount < 0) {
231 		/* it's laughable, but... */
232 		warncount = 0;
233 	}
234 
235 	memset(&tmp, 0, sizeof(struct __old_kernel_stat));
236 	tmp.st_dev = old_encode_dev(stat->dev);
237 	tmp.st_ino = stat->ino;
238 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
239 		return -EOVERFLOW;
240 	tmp.st_mode = stat->mode;
241 	tmp.st_nlink = stat->nlink;
242 	if (tmp.st_nlink != stat->nlink)
243 		return -EOVERFLOW;
244 	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
245 	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
246 	tmp.st_rdev = old_encode_dev(stat->rdev);
247 #if BITS_PER_LONG == 32
248 	if (stat->size > MAX_NON_LFS)
249 		return -EOVERFLOW;
250 #endif
251 	tmp.st_size = stat->size;
252 	tmp.st_atime = stat->atime.tv_sec;
253 	tmp.st_mtime = stat->mtime.tv_sec;
254 	tmp.st_ctime = stat->ctime.tv_sec;
255 	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
256 }
257 
258 SYSCALL_DEFINE2(stat, const char __user *, filename,
259 		struct __old_kernel_stat __user *, statbuf)
260 {
261 	struct kstat stat;
262 	int error;
263 
264 	error = vfs_stat(filename, &stat);
265 	if (error)
266 		return error;
267 
268 	return cp_old_stat(&stat, statbuf);
269 }
270 
271 SYSCALL_DEFINE2(lstat, const char __user *, filename,
272 		struct __old_kernel_stat __user *, statbuf)
273 {
274 	struct kstat stat;
275 	int error;
276 
277 	error = vfs_lstat(filename, &stat);
278 	if (error)
279 		return error;
280 
281 	return cp_old_stat(&stat, statbuf);
282 }
283 
284 SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
285 {
286 	struct kstat stat;
287 	int error = vfs_fstat(fd, &stat);
288 
289 	if (!error)
290 		error = cp_old_stat(&stat, statbuf);
291 
292 	return error;
293 }
294 
295 #endif /* __ARCH_WANT_OLD_STAT */
296 
297 #ifdef __ARCH_WANT_NEW_STAT
298 
299 #if BITS_PER_LONG == 32
300 #  define choose_32_64(a,b) a
301 #else
302 #  define choose_32_64(a,b) b
303 #endif
304 
305 #define valid_dev(x)  choose_32_64(old_valid_dev(x),true)
306 #define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
307 
308 #ifndef INIT_STRUCT_STAT_PADDING
309 #  define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
310 #endif
311 
312 static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
313 {
314 	struct stat tmp;
315 
316 	if (!valid_dev(stat->dev) || !valid_dev(stat->rdev))
317 		return -EOVERFLOW;
318 #if BITS_PER_LONG == 32
319 	if (stat->size > MAX_NON_LFS)
320 		return -EOVERFLOW;
321 #endif
322 
323 	INIT_STRUCT_STAT_PADDING(tmp);
324 	tmp.st_dev = encode_dev(stat->dev);
325 	tmp.st_ino = stat->ino;
326 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
327 		return -EOVERFLOW;
328 	tmp.st_mode = stat->mode;
329 	tmp.st_nlink = stat->nlink;
330 	if (tmp.st_nlink != stat->nlink)
331 		return -EOVERFLOW;
332 	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
333 	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
334 	tmp.st_rdev = encode_dev(stat->rdev);
335 	tmp.st_size = stat->size;
336 	tmp.st_atime = stat->atime.tv_sec;
337 	tmp.st_mtime = stat->mtime.tv_sec;
338 	tmp.st_ctime = stat->ctime.tv_sec;
339 #ifdef STAT_HAVE_NSEC
340 	tmp.st_atime_nsec = stat->atime.tv_nsec;
341 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
342 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
343 #endif
344 	tmp.st_blocks = stat->blocks;
345 	tmp.st_blksize = stat->blksize;
346 	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
347 }
348 
349 SYSCALL_DEFINE2(newstat, const char __user *, filename,
350 		struct stat __user *, statbuf)
351 {
352 	struct kstat stat;
353 	int error = vfs_stat(filename, &stat);
354 
355 	if (error)
356 		return error;
357 	return cp_new_stat(&stat, statbuf);
358 }
359 
360 SYSCALL_DEFINE2(newlstat, const char __user *, filename,
361 		struct stat __user *, statbuf)
362 {
363 	struct kstat stat;
364 	int error;
365 
366 	error = vfs_lstat(filename, &stat);
367 	if (error)
368 		return error;
369 
370 	return cp_new_stat(&stat, statbuf);
371 }
372 
373 #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
374 SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
375 		struct stat __user *, statbuf, int, flag)
376 {
377 	struct kstat stat;
378 	int error;
379 
380 	error = vfs_fstatat(dfd, filename, &stat, flag);
381 	if (error)
382 		return error;
383 	return cp_new_stat(&stat, statbuf);
384 }
385 #endif
386 
387 SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
388 {
389 	struct kstat stat;
390 	int error = vfs_fstat(fd, &stat);
391 
392 	if (!error)
393 		error = cp_new_stat(&stat, statbuf);
394 
395 	return error;
396 }
397 #endif
398 
399 static int do_readlinkat(int dfd, const char __user *pathname,
400 			 char __user *buf, int bufsiz)
401 {
402 	struct path path;
403 	int error;
404 	int empty = 0;
405 	unsigned int lookup_flags = LOOKUP_EMPTY;
406 
407 	if (bufsiz <= 0)
408 		return -EINVAL;
409 
410 retry:
411 	error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
412 	if (!error) {
413 		struct inode *inode = d_backing_inode(path.dentry);
414 
415 		error = empty ? -ENOENT : -EINVAL;
416 		/*
417 		 * AFS mountpoints allow readlink(2) but are not symlinks
418 		 */
419 		if (d_is_symlink(path.dentry) || inode->i_op->readlink) {
420 			error = security_inode_readlink(path.dentry);
421 			if (!error) {
422 				touch_atime(&path);
423 				error = vfs_readlink(path.dentry, buf, bufsiz);
424 			}
425 		}
426 		path_put(&path);
427 		if (retry_estale(error, lookup_flags)) {
428 			lookup_flags |= LOOKUP_REVAL;
429 			goto retry;
430 		}
431 	}
432 	return error;
433 }
434 
435 SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
436 		char __user *, buf, int, bufsiz)
437 {
438 	return do_readlinkat(dfd, pathname, buf, bufsiz);
439 }
440 
441 SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
442 		int, bufsiz)
443 {
444 	return do_readlinkat(AT_FDCWD, path, buf, bufsiz);
445 }
446 
447 
448 /* ---------- LFS-64 ----------- */
449 #if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
450 
451 #ifndef INIT_STRUCT_STAT64_PADDING
452 #  define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
453 #endif
454 
455 static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
456 {
457 	struct stat64 tmp;
458 
459 	INIT_STRUCT_STAT64_PADDING(tmp);
460 #ifdef CONFIG_MIPS
461 	/* mips has weird padding, so we don't get 64 bits there */
462 	tmp.st_dev = new_encode_dev(stat->dev);
463 	tmp.st_rdev = new_encode_dev(stat->rdev);
464 #else
465 	tmp.st_dev = huge_encode_dev(stat->dev);
466 	tmp.st_rdev = huge_encode_dev(stat->rdev);
467 #endif
468 	tmp.st_ino = stat->ino;
469 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
470 		return -EOVERFLOW;
471 #ifdef STAT64_HAS_BROKEN_ST_INO
472 	tmp.__st_ino = stat->ino;
473 #endif
474 	tmp.st_mode = stat->mode;
475 	tmp.st_nlink = stat->nlink;
476 	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
477 	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
478 	tmp.st_atime = stat->atime.tv_sec;
479 	tmp.st_atime_nsec = stat->atime.tv_nsec;
480 	tmp.st_mtime = stat->mtime.tv_sec;
481 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
482 	tmp.st_ctime = stat->ctime.tv_sec;
483 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
484 	tmp.st_size = stat->size;
485 	tmp.st_blocks = stat->blocks;
486 	tmp.st_blksize = stat->blksize;
487 	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
488 }
489 
490 SYSCALL_DEFINE2(stat64, const char __user *, filename,
491 		struct stat64 __user *, statbuf)
492 {
493 	struct kstat stat;
494 	int error = vfs_stat(filename, &stat);
495 
496 	if (!error)
497 		error = cp_new_stat64(&stat, statbuf);
498 
499 	return error;
500 }
501 
502 SYSCALL_DEFINE2(lstat64, const char __user *, filename,
503 		struct stat64 __user *, statbuf)
504 {
505 	struct kstat stat;
506 	int error = vfs_lstat(filename, &stat);
507 
508 	if (!error)
509 		error = cp_new_stat64(&stat, statbuf);
510 
511 	return error;
512 }
513 
514 SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
515 {
516 	struct kstat stat;
517 	int error = vfs_fstat(fd, &stat);
518 
519 	if (!error)
520 		error = cp_new_stat64(&stat, statbuf);
521 
522 	return error;
523 }
524 
525 SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
526 		struct stat64 __user *, statbuf, int, flag)
527 {
528 	struct kstat stat;
529 	int error;
530 
531 	error = vfs_fstatat(dfd, filename, &stat, flag);
532 	if (error)
533 		return error;
534 	return cp_new_stat64(&stat, statbuf);
535 }
536 #endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
537 
538 static noinline_for_stack int
539 cp_statx(const struct kstat *stat, struct statx __user *buffer)
540 {
541 	struct statx tmp;
542 
543 	memset(&tmp, 0, sizeof(tmp));
544 
545 	tmp.stx_mask = stat->result_mask;
546 	tmp.stx_blksize = stat->blksize;
547 	tmp.stx_attributes = stat->attributes;
548 	tmp.stx_nlink = stat->nlink;
549 	tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid);
550 	tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid);
551 	tmp.stx_mode = stat->mode;
552 	tmp.stx_ino = stat->ino;
553 	tmp.stx_size = stat->size;
554 	tmp.stx_blocks = stat->blocks;
555 	tmp.stx_attributes_mask = stat->attributes_mask;
556 	tmp.stx_atime.tv_sec = stat->atime.tv_sec;
557 	tmp.stx_atime.tv_nsec = stat->atime.tv_nsec;
558 	tmp.stx_btime.tv_sec = stat->btime.tv_sec;
559 	tmp.stx_btime.tv_nsec = stat->btime.tv_nsec;
560 	tmp.stx_ctime.tv_sec = stat->ctime.tv_sec;
561 	tmp.stx_ctime.tv_nsec = stat->ctime.tv_nsec;
562 	tmp.stx_mtime.tv_sec = stat->mtime.tv_sec;
563 	tmp.stx_mtime.tv_nsec = stat->mtime.tv_nsec;
564 	tmp.stx_rdev_major = MAJOR(stat->rdev);
565 	tmp.stx_rdev_minor = MINOR(stat->rdev);
566 	tmp.stx_dev_major = MAJOR(stat->dev);
567 	tmp.stx_dev_minor = MINOR(stat->dev);
568 	tmp.stx_mnt_id = stat->mnt_id;
569 
570 	return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
571 }
572 
573 int do_statx(int dfd, const char __user *filename, unsigned flags,
574 	     unsigned int mask, struct statx __user *buffer)
575 {
576 	struct kstat stat;
577 	int error;
578 
579 	if (mask & STATX__RESERVED)
580 		return -EINVAL;
581 	if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
582 		return -EINVAL;
583 
584 	error = vfs_statx(dfd, filename, flags, &stat, mask);
585 	if (error)
586 		return error;
587 
588 	return cp_statx(&stat, buffer);
589 }
590 
591 /**
592  * sys_statx - System call to get enhanced stats
593  * @dfd: Base directory to pathwalk from *or* fd to stat.
594  * @filename: File to stat or "" with AT_EMPTY_PATH
595  * @flags: AT_* flags to control pathwalk.
596  * @mask: Parts of statx struct actually required.
597  * @buffer: Result buffer.
598  *
599  * Note that fstat() can be emulated by setting dfd to the fd of interest,
600  * supplying "" as the filename and setting AT_EMPTY_PATH in the flags.
601  */
602 SYSCALL_DEFINE5(statx,
603 		int, dfd, const char __user *, filename, unsigned, flags,
604 		unsigned int, mask,
605 		struct statx __user *, buffer)
606 {
607 	return do_statx(dfd, filename, flags, mask, buffer);
608 }
609 
610 #ifdef CONFIG_COMPAT
611 static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
612 {
613 	struct compat_stat tmp;
614 
615 	if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
616 		return -EOVERFLOW;
617 
618 	memset(&tmp, 0, sizeof(tmp));
619 	tmp.st_dev = old_encode_dev(stat->dev);
620 	tmp.st_ino = stat->ino;
621 	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
622 		return -EOVERFLOW;
623 	tmp.st_mode = stat->mode;
624 	tmp.st_nlink = stat->nlink;
625 	if (tmp.st_nlink != stat->nlink)
626 		return -EOVERFLOW;
627 	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
628 	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
629 	tmp.st_rdev = old_encode_dev(stat->rdev);
630 	if ((u64) stat->size > MAX_NON_LFS)
631 		return -EOVERFLOW;
632 	tmp.st_size = stat->size;
633 	tmp.st_atime = stat->atime.tv_sec;
634 	tmp.st_atime_nsec = stat->atime.tv_nsec;
635 	tmp.st_mtime = stat->mtime.tv_sec;
636 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
637 	tmp.st_ctime = stat->ctime.tv_sec;
638 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
639 	tmp.st_blocks = stat->blocks;
640 	tmp.st_blksize = stat->blksize;
641 	return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
642 }
643 
644 COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename,
645 		       struct compat_stat __user *, statbuf)
646 {
647 	struct kstat stat;
648 	int error;
649 
650 	error = vfs_stat(filename, &stat);
651 	if (error)
652 		return error;
653 	return cp_compat_stat(&stat, statbuf);
654 }
655 
656 COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename,
657 		       struct compat_stat __user *, statbuf)
658 {
659 	struct kstat stat;
660 	int error;
661 
662 	error = vfs_lstat(filename, &stat);
663 	if (error)
664 		return error;
665 	return cp_compat_stat(&stat, statbuf);
666 }
667 
668 #ifndef __ARCH_WANT_STAT64
669 COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd,
670 		       const char __user *, filename,
671 		       struct compat_stat __user *, statbuf, int, flag)
672 {
673 	struct kstat stat;
674 	int error;
675 
676 	error = vfs_fstatat(dfd, filename, &stat, flag);
677 	if (error)
678 		return error;
679 	return cp_compat_stat(&stat, statbuf);
680 }
681 #endif
682 
683 COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd,
684 		       struct compat_stat __user *, statbuf)
685 {
686 	struct kstat stat;
687 	int error = vfs_fstat(fd, &stat);
688 
689 	if (!error)
690 		error = cp_compat_stat(&stat, statbuf);
691 	return error;
692 }
693 #endif
694 
695 /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
696 void __inode_add_bytes(struct inode *inode, loff_t bytes)
697 {
698 	inode->i_blocks += bytes >> 9;
699 	bytes &= 511;
700 	inode->i_bytes += bytes;
701 	if (inode->i_bytes >= 512) {
702 		inode->i_blocks++;
703 		inode->i_bytes -= 512;
704 	}
705 }
706 EXPORT_SYMBOL(__inode_add_bytes);
707 
708 void inode_add_bytes(struct inode *inode, loff_t bytes)
709 {
710 	spin_lock(&inode->i_lock);
711 	__inode_add_bytes(inode, bytes);
712 	spin_unlock(&inode->i_lock);
713 }
714 
715 EXPORT_SYMBOL(inode_add_bytes);
716 
717 void __inode_sub_bytes(struct inode *inode, loff_t bytes)
718 {
719 	inode->i_blocks -= bytes >> 9;
720 	bytes &= 511;
721 	if (inode->i_bytes < bytes) {
722 		inode->i_blocks--;
723 		inode->i_bytes += 512;
724 	}
725 	inode->i_bytes -= bytes;
726 }
727 
728 EXPORT_SYMBOL(__inode_sub_bytes);
729 
730 void inode_sub_bytes(struct inode *inode, loff_t bytes)
731 {
732 	spin_lock(&inode->i_lock);
733 	__inode_sub_bytes(inode, bytes);
734 	spin_unlock(&inode->i_lock);
735 }
736 
737 EXPORT_SYMBOL(inode_sub_bytes);
738 
739 loff_t inode_get_bytes(struct inode *inode)
740 {
741 	loff_t ret;
742 
743 	spin_lock(&inode->i_lock);
744 	ret = __inode_get_bytes(inode);
745 	spin_unlock(&inode->i_lock);
746 	return ret;
747 }
748 
749 EXPORT_SYMBOL(inode_get_bytes);
750 
751 void inode_set_bytes(struct inode *inode, loff_t bytes)
752 {
753 	/* Caller is here responsible for sufficient locking
754 	 * (ie. inode->i_lock) */
755 	inode->i_blocks = bytes >> 9;
756 	inode->i_bytes = bytes & 511;
757 }
758 
759 EXPORT_SYMBOL(inode_set_bytes);
760