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1/*
2 * linux/fs/stat.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/export.h>
8#include <linux/mm.h>
9#include <linux/errno.h>
10#include <linux/file.h>
11#include <linux/highuid.h>
12#include <linux/fs.h>
13#include <linux/namei.h>
14#include <linux/security.h>
15#include <linux/syscalls.h>
16#include <linux/pagemap.h>
17
18#include <asm/uaccess.h>
19#include <asm/unistd.h>
20
21void generic_fillattr(struct inode *inode, struct kstat *stat)
22{
23 stat->dev = inode->i_sb->s_dev;
24 stat->ino = inode->i_ino;
25 stat->mode = inode->i_mode;
26 stat->nlink = inode->i_nlink;
27 stat->uid = inode->i_uid;
28 stat->gid = inode->i_gid;
29 stat->rdev = inode->i_rdev;
30 stat->size = i_size_read(inode);
31 stat->atime = inode->i_atime;
32 stat->mtime = inode->i_mtime;
33 stat->ctime = inode->i_ctime;
34 stat->blksize = (1 << inode->i_blkbits);
35 stat->blocks = inode->i_blocks;
36}
37
38EXPORT_SYMBOL(generic_fillattr);
39
40/**
41 * vfs_getattr_nosec - getattr without security checks
42 * @path: file to get attributes from
43 * @stat: structure to return attributes in
44 *
45 * Get attributes without calling security_inode_getattr.
46 *
47 * Currently the only caller other than vfs_getattr is internal to the
48 * filehandle lookup code, which uses only the inode number and returns
49 * no attributes to any user. Any other code probably wants
50 * vfs_getattr.
51 */
52int vfs_getattr_nosec(struct path *path, struct kstat *stat)
53{
54 struct inode *inode = path->dentry->d_inode;
55
56 if (inode->i_op->getattr)
57 return inode->i_op->getattr(path->mnt, path->dentry, stat);
58
59 generic_fillattr(inode, stat);
60 return 0;
61}
62
63EXPORT_SYMBOL(vfs_getattr_nosec);
64
65int vfs_getattr(struct path *path, struct kstat *stat)
66{
67 int retval;
68
69 retval = security_inode_getattr(path->mnt, path->dentry);
70 if (retval)
71 return retval;
72 return vfs_getattr_nosec(path, stat);
73}
74
75EXPORT_SYMBOL(vfs_getattr);
76
77int vfs_fstat(unsigned int fd, struct kstat *stat)
78{
79 struct fd f = fdget_raw(fd);
80 int error = -EBADF;
81
82 if (f.file) {
83 error = vfs_getattr(&f.file->f_path, stat);
84 fdput(f);
85 }
86 return error;
87}
88EXPORT_SYMBOL(vfs_fstat);
89
90int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
91 int flag)
92{
93 struct path path;
94 int error = -EINVAL;
95 unsigned int lookup_flags = 0;
96
97 if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
98 AT_EMPTY_PATH)) != 0)
99 goto out;
100
101 if (!(flag & AT_SYMLINK_NOFOLLOW))
102 lookup_flags |= LOOKUP_FOLLOW;
103 if (flag & AT_EMPTY_PATH)
104 lookup_flags |= LOOKUP_EMPTY;
105retry:
106 error = user_path_at(dfd, filename, lookup_flags, &path);
107 if (error)
108 goto out;
109
110 error = vfs_getattr(&path, stat);
111 path_put(&path);
112 if (retry_estale(error, lookup_flags)) {
113 lookup_flags |= LOOKUP_REVAL;
114 goto retry;
115 }
116out:
117 return error;
118}
119EXPORT_SYMBOL(vfs_fstatat);
120
121int vfs_stat(const char __user *name, struct kstat *stat)
122{
123 return vfs_fstatat(AT_FDCWD, name, stat, 0);
124}
125EXPORT_SYMBOL(vfs_stat);
126
127int vfs_lstat(const char __user *name, struct kstat *stat)
128{
129 return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
130}
131EXPORT_SYMBOL(vfs_lstat);
132
133
134#ifdef __ARCH_WANT_OLD_STAT
135
136/*
137 * For backward compatibility? Maybe this should be moved
138 * into arch/i386 instead?
139 */
140static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
141{
142 static int warncount = 5;
143 struct __old_kernel_stat tmp;
144
145 if (warncount > 0) {
146 warncount--;
147 printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
148 current->comm);
149 } else if (warncount < 0) {
150 /* it's laughable, but... */
151 warncount = 0;
152 }
153
154 memset(&tmp, 0, sizeof(struct __old_kernel_stat));
155 tmp.st_dev = old_encode_dev(stat->dev);
156 tmp.st_ino = stat->ino;
157 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
158 return -EOVERFLOW;
159 tmp.st_mode = stat->mode;
160 tmp.st_nlink = stat->nlink;
161 if (tmp.st_nlink != stat->nlink)
162 return -EOVERFLOW;
163 SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
164 SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
165 tmp.st_rdev = old_encode_dev(stat->rdev);
166#if BITS_PER_LONG == 32
167 if (stat->size > MAX_NON_LFS)
168 return -EOVERFLOW;
169#endif
170 tmp.st_size = stat->size;
171 tmp.st_atime = stat->atime.tv_sec;
172 tmp.st_mtime = stat->mtime.tv_sec;
173 tmp.st_ctime = stat->ctime.tv_sec;
174 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
175}
176
177SYSCALL_DEFINE2(stat, const char __user *, filename,
178 struct __old_kernel_stat __user *, statbuf)
179{
180 struct kstat stat;
181 int error;
182
183 error = vfs_stat(filename, &stat);
184 if (error)
185 return error;
186
187 return cp_old_stat(&stat, statbuf);
188}
189
190SYSCALL_DEFINE2(lstat, const char __user *, filename,
191 struct __old_kernel_stat __user *, statbuf)
192{
193 struct kstat stat;
194 int error;
195
196 error = vfs_lstat(filename, &stat);
197 if (error)
198 return error;
199
200 return cp_old_stat(&stat, statbuf);
201}
202
203SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
204{
205 struct kstat stat;
206 int error = vfs_fstat(fd, &stat);
207
208 if (!error)
209 error = cp_old_stat(&stat, statbuf);
210
211 return error;
212}
213
214#endif /* __ARCH_WANT_OLD_STAT */
215
216#if BITS_PER_LONG == 32
217# define choose_32_64(a,b) a
218#else
219# define choose_32_64(a,b) b
220#endif
221
222#define valid_dev(x) choose_32_64(old_valid_dev,new_valid_dev)(x)
223#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
224
225#ifndef INIT_STRUCT_STAT_PADDING
226# define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
227#endif
228
229static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
230{
231 struct stat tmp;
232
233 if (!valid_dev(stat->dev) || !valid_dev(stat->rdev))
234 return -EOVERFLOW;
235#if BITS_PER_LONG == 32
236 if (stat->size > MAX_NON_LFS)
237 return -EOVERFLOW;
238#endif
239
240 INIT_STRUCT_STAT_PADDING(tmp);
241 tmp.st_dev = encode_dev(stat->dev);
242 tmp.st_ino = stat->ino;
243 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
244 return -EOVERFLOW;
245 tmp.st_mode = stat->mode;
246 tmp.st_nlink = stat->nlink;
247 if (tmp.st_nlink != stat->nlink)
248 return -EOVERFLOW;
249 SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
250 SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
251 tmp.st_rdev = encode_dev(stat->rdev);
252 tmp.st_size = stat->size;
253 tmp.st_atime = stat->atime.tv_sec;
254 tmp.st_mtime = stat->mtime.tv_sec;
255 tmp.st_ctime = stat->ctime.tv_sec;
256#ifdef STAT_HAVE_NSEC
257 tmp.st_atime_nsec = stat->atime.tv_nsec;
258 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
259 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
260#endif
261 tmp.st_blocks = stat->blocks;
262 tmp.st_blksize = stat->blksize;
263 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
264}
265
266SYSCALL_DEFINE2(newstat, const char __user *, filename,
267 struct stat __user *, statbuf)
268{
269 struct kstat stat;
270 int error = vfs_stat(filename, &stat);
271
272 if (error)
273 return error;
274 return cp_new_stat(&stat, statbuf);
275}
276
277SYSCALL_DEFINE2(newlstat, const char __user *, filename,
278 struct stat __user *, statbuf)
279{
280 struct kstat stat;
281 int error;
282
283 error = vfs_lstat(filename, &stat);
284 if (error)
285 return error;
286
287 return cp_new_stat(&stat, statbuf);
288}
289
290#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
291SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
292 struct stat __user *, statbuf, int, flag)
293{
294 struct kstat stat;
295 int error;
296
297 error = vfs_fstatat(dfd, filename, &stat, flag);
298 if (error)
299 return error;
300 return cp_new_stat(&stat, statbuf);
301}
302#endif
303
304SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
305{
306 struct kstat stat;
307 int error = vfs_fstat(fd, &stat);
308
309 if (!error)
310 error = cp_new_stat(&stat, statbuf);
311
312 return error;
313}
314
315SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
316 char __user *, buf, int, bufsiz)
317{
318 struct path path;
319 int error;
320 int empty = 0;
321 unsigned int lookup_flags = LOOKUP_EMPTY;
322
323 if (bufsiz <= 0)
324 return -EINVAL;
325
326retry:
327 error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
328 if (!error) {
329 struct inode *inode = path.dentry->d_inode;
330
331 error = empty ? -ENOENT : -EINVAL;
332 if (inode->i_op->readlink) {
333 error = security_inode_readlink(path.dentry);
334 if (!error) {
335 touch_atime(&path);
336 error = inode->i_op->readlink(path.dentry,
337 buf, bufsiz);
338 }
339 }
340 path_put(&path);
341 if (retry_estale(error, lookup_flags)) {
342 lookup_flags |= LOOKUP_REVAL;
343 goto retry;
344 }
345 }
346 return error;
347}
348
349SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
350 int, bufsiz)
351{
352 return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
353}
354
355
356/* ---------- LFS-64 ----------- */
357#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
358
359#ifndef INIT_STRUCT_STAT64_PADDING
360# define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
361#endif
362
363static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
364{
365 struct stat64 tmp;
366
367 INIT_STRUCT_STAT64_PADDING(tmp);
368#ifdef CONFIG_MIPS
369 /* mips has weird padding, so we don't get 64 bits there */
370 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
371 return -EOVERFLOW;
372 tmp.st_dev = new_encode_dev(stat->dev);
373 tmp.st_rdev = new_encode_dev(stat->rdev);
374#else
375 tmp.st_dev = huge_encode_dev(stat->dev);
376 tmp.st_rdev = huge_encode_dev(stat->rdev);
377#endif
378 tmp.st_ino = stat->ino;
379 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
380 return -EOVERFLOW;
381#ifdef STAT64_HAS_BROKEN_ST_INO
382 tmp.__st_ino = stat->ino;
383#endif
384 tmp.st_mode = stat->mode;
385 tmp.st_nlink = stat->nlink;
386 tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
387 tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
388 tmp.st_atime = stat->atime.tv_sec;
389 tmp.st_atime_nsec = stat->atime.tv_nsec;
390 tmp.st_mtime = stat->mtime.tv_sec;
391 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
392 tmp.st_ctime = stat->ctime.tv_sec;
393 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
394 tmp.st_size = stat->size;
395 tmp.st_blocks = stat->blocks;
396 tmp.st_blksize = stat->blksize;
397 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
398}
399
400SYSCALL_DEFINE2(stat64, const char __user *, filename,
401 struct stat64 __user *, statbuf)
402{
403 struct kstat stat;
404 int error = vfs_stat(filename, &stat);
405
406 if (!error)
407 error = cp_new_stat64(&stat, statbuf);
408
409 return error;
410}
411
412SYSCALL_DEFINE2(lstat64, const char __user *, filename,
413 struct stat64 __user *, statbuf)
414{
415 struct kstat stat;
416 int error = vfs_lstat(filename, &stat);
417
418 if (!error)
419 error = cp_new_stat64(&stat, statbuf);
420
421 return error;
422}
423
424SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
425{
426 struct kstat stat;
427 int error = vfs_fstat(fd, &stat);
428
429 if (!error)
430 error = cp_new_stat64(&stat, statbuf);
431
432 return error;
433}
434
435SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
436 struct stat64 __user *, statbuf, int, flag)
437{
438 struct kstat stat;
439 int error;
440
441 error = vfs_fstatat(dfd, filename, &stat, flag);
442 if (error)
443 return error;
444 return cp_new_stat64(&stat, statbuf);
445}
446#endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
447
448/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
449void __inode_add_bytes(struct inode *inode, loff_t bytes)
450{
451 inode->i_blocks += bytes >> 9;
452 bytes &= 511;
453 inode->i_bytes += bytes;
454 if (inode->i_bytes >= 512) {
455 inode->i_blocks++;
456 inode->i_bytes -= 512;
457 }
458}
459
460void inode_add_bytes(struct inode *inode, loff_t bytes)
461{
462 spin_lock(&inode->i_lock);
463 __inode_add_bytes(inode, bytes);
464 spin_unlock(&inode->i_lock);
465}
466
467EXPORT_SYMBOL(inode_add_bytes);
468
469void __inode_sub_bytes(struct inode *inode, loff_t bytes)
470{
471 inode->i_blocks -= bytes >> 9;
472 bytes &= 511;
473 if (inode->i_bytes < bytes) {
474 inode->i_blocks--;
475 inode->i_bytes += 512;
476 }
477 inode->i_bytes -= bytes;
478}
479
480EXPORT_SYMBOL(__inode_sub_bytes);
481
482void inode_sub_bytes(struct inode *inode, loff_t bytes)
483{
484 spin_lock(&inode->i_lock);
485 __inode_sub_bytes(inode, bytes);
486 spin_unlock(&inode->i_lock);
487}
488
489EXPORT_SYMBOL(inode_sub_bytes);
490
491loff_t inode_get_bytes(struct inode *inode)
492{
493 loff_t ret;
494
495 spin_lock(&inode->i_lock);
496 ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
497 spin_unlock(&inode->i_lock);
498 return ret;
499}
500
501EXPORT_SYMBOL(inode_get_bytes);
502
503void inode_set_bytes(struct inode *inode, loff_t bytes)
504{
505 /* Caller is here responsible for sufficient locking
506 * (ie. inode->i_lock) */
507 inode->i_blocks = bytes >> 9;
508 inode->i_bytes = bytes & 511;
509}
510
511EXPORT_SYMBOL(inode_set_bytes);
1/*
2 * linux/fs/stat.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/export.h>
8#include <linux/mm.h>
9#include <linux/errno.h>
10#include <linux/file.h>
11#include <linux/highuid.h>
12#include <linux/fs.h>
13#include <linux/namei.h>
14#include <linux/security.h>
15#include <linux/syscalls.h>
16#include <linux/pagemap.h>
17
18#include <asm/uaccess.h>
19#include <asm/unistd.h>
20
21void generic_fillattr(struct inode *inode, struct kstat *stat)
22{
23 stat->dev = inode->i_sb->s_dev;
24 stat->ino = inode->i_ino;
25 stat->mode = inode->i_mode;
26 stat->nlink = inode->i_nlink;
27 stat->uid = inode->i_uid;
28 stat->gid = inode->i_gid;
29 stat->rdev = inode->i_rdev;
30 stat->size = i_size_read(inode);
31 stat->atime = inode->i_atime;
32 stat->mtime = inode->i_mtime;
33 stat->ctime = inode->i_ctime;
34 stat->blksize = (1 << inode->i_blkbits);
35 stat->blocks = inode->i_blocks;
36}
37
38EXPORT_SYMBOL(generic_fillattr);
39
40int vfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
41{
42 struct inode *inode = dentry->d_inode;
43 int retval;
44
45 retval = security_inode_getattr(mnt, dentry);
46 if (retval)
47 return retval;
48
49 if (inode->i_op->getattr)
50 return inode->i_op->getattr(mnt, dentry, stat);
51
52 generic_fillattr(inode, stat);
53 return 0;
54}
55
56EXPORT_SYMBOL(vfs_getattr);
57
58int vfs_fstat(unsigned int fd, struct kstat *stat)
59{
60 int fput_needed;
61 struct file *f = fget_raw_light(fd, &fput_needed);
62 int error = -EBADF;
63
64 if (f) {
65 error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat);
66 fput_light(f, fput_needed);
67 }
68 return error;
69}
70EXPORT_SYMBOL(vfs_fstat);
71
72int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
73 int flag)
74{
75 struct path path;
76 int error = -EINVAL;
77 int lookup_flags = 0;
78
79 if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
80 AT_EMPTY_PATH)) != 0)
81 goto out;
82
83 if (!(flag & AT_SYMLINK_NOFOLLOW))
84 lookup_flags |= LOOKUP_FOLLOW;
85 if (flag & AT_EMPTY_PATH)
86 lookup_flags |= LOOKUP_EMPTY;
87
88 error = user_path_at(dfd, filename, lookup_flags, &path);
89 if (error)
90 goto out;
91
92 error = vfs_getattr(path.mnt, path.dentry, stat);
93 path_put(&path);
94out:
95 return error;
96}
97EXPORT_SYMBOL(vfs_fstatat);
98
99int vfs_stat(const char __user *name, struct kstat *stat)
100{
101 return vfs_fstatat(AT_FDCWD, name, stat, 0);
102}
103EXPORT_SYMBOL(vfs_stat);
104
105int vfs_lstat(const char __user *name, struct kstat *stat)
106{
107 return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
108}
109EXPORT_SYMBOL(vfs_lstat);
110
111
112#ifdef __ARCH_WANT_OLD_STAT
113
114/*
115 * For backward compatibility? Maybe this should be moved
116 * into arch/i386 instead?
117 */
118static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
119{
120 static int warncount = 5;
121 struct __old_kernel_stat tmp;
122
123 if (warncount > 0) {
124 warncount--;
125 printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
126 current->comm);
127 } else if (warncount < 0) {
128 /* it's laughable, but... */
129 warncount = 0;
130 }
131
132 memset(&tmp, 0, sizeof(struct __old_kernel_stat));
133 tmp.st_dev = old_encode_dev(stat->dev);
134 tmp.st_ino = stat->ino;
135 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
136 return -EOVERFLOW;
137 tmp.st_mode = stat->mode;
138 tmp.st_nlink = stat->nlink;
139 if (tmp.st_nlink != stat->nlink)
140 return -EOVERFLOW;
141 SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
142 SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
143 tmp.st_rdev = old_encode_dev(stat->rdev);
144#if BITS_PER_LONG == 32
145 if (stat->size > MAX_NON_LFS)
146 return -EOVERFLOW;
147#endif
148 tmp.st_size = stat->size;
149 tmp.st_atime = stat->atime.tv_sec;
150 tmp.st_mtime = stat->mtime.tv_sec;
151 tmp.st_ctime = stat->ctime.tv_sec;
152 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
153}
154
155SYSCALL_DEFINE2(stat, const char __user *, filename,
156 struct __old_kernel_stat __user *, statbuf)
157{
158 struct kstat stat;
159 int error;
160
161 error = vfs_stat(filename, &stat);
162 if (error)
163 return error;
164
165 return cp_old_stat(&stat, statbuf);
166}
167
168SYSCALL_DEFINE2(lstat, const char __user *, filename,
169 struct __old_kernel_stat __user *, statbuf)
170{
171 struct kstat stat;
172 int error;
173
174 error = vfs_lstat(filename, &stat);
175 if (error)
176 return error;
177
178 return cp_old_stat(&stat, statbuf);
179}
180
181SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
182{
183 struct kstat stat;
184 int error = vfs_fstat(fd, &stat);
185
186 if (!error)
187 error = cp_old_stat(&stat, statbuf);
188
189 return error;
190}
191
192#endif /* __ARCH_WANT_OLD_STAT */
193
194#if BITS_PER_LONG == 32
195# define choose_32_64(a,b) a
196#else
197# define choose_32_64(a,b) b
198#endif
199
200#define valid_dev(x) choose_32_64(old_valid_dev,new_valid_dev)(x)
201#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
202
203#ifndef INIT_STRUCT_STAT_PADDING
204# define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
205#endif
206
207static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
208{
209 struct stat tmp;
210
211 if (!valid_dev(stat->dev) || !valid_dev(stat->rdev))
212 return -EOVERFLOW;
213#if BITS_PER_LONG == 32
214 if (stat->size > MAX_NON_LFS)
215 return -EOVERFLOW;
216#endif
217
218 INIT_STRUCT_STAT_PADDING(tmp);
219 tmp.st_dev = encode_dev(stat->dev);
220 tmp.st_ino = stat->ino;
221 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
222 return -EOVERFLOW;
223 tmp.st_mode = stat->mode;
224 tmp.st_nlink = stat->nlink;
225 if (tmp.st_nlink != stat->nlink)
226 return -EOVERFLOW;
227 SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
228 SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
229 tmp.st_rdev = encode_dev(stat->rdev);
230 tmp.st_size = stat->size;
231 tmp.st_atime = stat->atime.tv_sec;
232 tmp.st_mtime = stat->mtime.tv_sec;
233 tmp.st_ctime = stat->ctime.tv_sec;
234#ifdef STAT_HAVE_NSEC
235 tmp.st_atime_nsec = stat->atime.tv_nsec;
236 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
237 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
238#endif
239 tmp.st_blocks = stat->blocks;
240 tmp.st_blksize = stat->blksize;
241 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
242}
243
244SYSCALL_DEFINE2(newstat, const char __user *, filename,
245 struct stat __user *, statbuf)
246{
247 struct kstat stat;
248 int error = vfs_stat(filename, &stat);
249
250 if (error)
251 return error;
252 return cp_new_stat(&stat, statbuf);
253}
254
255SYSCALL_DEFINE2(newlstat, const char __user *, filename,
256 struct stat __user *, statbuf)
257{
258 struct kstat stat;
259 int error;
260
261 error = vfs_lstat(filename, &stat);
262 if (error)
263 return error;
264
265 return cp_new_stat(&stat, statbuf);
266}
267
268#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
269SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
270 struct stat __user *, statbuf, int, flag)
271{
272 struct kstat stat;
273 int error;
274
275 error = vfs_fstatat(dfd, filename, &stat, flag);
276 if (error)
277 return error;
278 return cp_new_stat(&stat, statbuf);
279}
280#endif
281
282SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
283{
284 struct kstat stat;
285 int error = vfs_fstat(fd, &stat);
286
287 if (!error)
288 error = cp_new_stat(&stat, statbuf);
289
290 return error;
291}
292
293SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
294 char __user *, buf, int, bufsiz)
295{
296 struct path path;
297 int error;
298 int empty = 0;
299
300 if (bufsiz <= 0)
301 return -EINVAL;
302
303 error = user_path_at_empty(dfd, pathname, LOOKUP_EMPTY, &path, &empty);
304 if (!error) {
305 struct inode *inode = path.dentry->d_inode;
306
307 error = empty ? -ENOENT : -EINVAL;
308 if (inode->i_op->readlink) {
309 error = security_inode_readlink(path.dentry);
310 if (!error) {
311 touch_atime(&path);
312 error = inode->i_op->readlink(path.dentry,
313 buf, bufsiz);
314 }
315 }
316 path_put(&path);
317 }
318 return error;
319}
320
321SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
322 int, bufsiz)
323{
324 return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
325}
326
327
328/* ---------- LFS-64 ----------- */
329#ifdef __ARCH_WANT_STAT64
330
331#ifndef INIT_STRUCT_STAT64_PADDING
332# define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
333#endif
334
335static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
336{
337 struct stat64 tmp;
338
339 INIT_STRUCT_STAT64_PADDING(tmp);
340#ifdef CONFIG_MIPS
341 /* mips has weird padding, so we don't get 64 bits there */
342 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
343 return -EOVERFLOW;
344 tmp.st_dev = new_encode_dev(stat->dev);
345 tmp.st_rdev = new_encode_dev(stat->rdev);
346#else
347 tmp.st_dev = huge_encode_dev(stat->dev);
348 tmp.st_rdev = huge_encode_dev(stat->rdev);
349#endif
350 tmp.st_ino = stat->ino;
351 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
352 return -EOVERFLOW;
353#ifdef STAT64_HAS_BROKEN_ST_INO
354 tmp.__st_ino = stat->ino;
355#endif
356 tmp.st_mode = stat->mode;
357 tmp.st_nlink = stat->nlink;
358 tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
359 tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
360 tmp.st_atime = stat->atime.tv_sec;
361 tmp.st_atime_nsec = stat->atime.tv_nsec;
362 tmp.st_mtime = stat->mtime.tv_sec;
363 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
364 tmp.st_ctime = stat->ctime.tv_sec;
365 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
366 tmp.st_size = stat->size;
367 tmp.st_blocks = stat->blocks;
368 tmp.st_blksize = stat->blksize;
369 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
370}
371
372SYSCALL_DEFINE2(stat64, const char __user *, filename,
373 struct stat64 __user *, statbuf)
374{
375 struct kstat stat;
376 int error = vfs_stat(filename, &stat);
377
378 if (!error)
379 error = cp_new_stat64(&stat, statbuf);
380
381 return error;
382}
383
384SYSCALL_DEFINE2(lstat64, const char __user *, filename,
385 struct stat64 __user *, statbuf)
386{
387 struct kstat stat;
388 int error = vfs_lstat(filename, &stat);
389
390 if (!error)
391 error = cp_new_stat64(&stat, statbuf);
392
393 return error;
394}
395
396SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
397{
398 struct kstat stat;
399 int error = vfs_fstat(fd, &stat);
400
401 if (!error)
402 error = cp_new_stat64(&stat, statbuf);
403
404 return error;
405}
406
407SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
408 struct stat64 __user *, statbuf, int, flag)
409{
410 struct kstat stat;
411 int error;
412
413 error = vfs_fstatat(dfd, filename, &stat, flag);
414 if (error)
415 return error;
416 return cp_new_stat64(&stat, statbuf);
417}
418#endif /* __ARCH_WANT_STAT64 */
419
420/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
421void __inode_add_bytes(struct inode *inode, loff_t bytes)
422{
423 inode->i_blocks += bytes >> 9;
424 bytes &= 511;
425 inode->i_bytes += bytes;
426 if (inode->i_bytes >= 512) {
427 inode->i_blocks++;
428 inode->i_bytes -= 512;
429 }
430}
431
432void inode_add_bytes(struct inode *inode, loff_t bytes)
433{
434 spin_lock(&inode->i_lock);
435 __inode_add_bytes(inode, bytes);
436 spin_unlock(&inode->i_lock);
437}
438
439EXPORT_SYMBOL(inode_add_bytes);
440
441void inode_sub_bytes(struct inode *inode, loff_t bytes)
442{
443 spin_lock(&inode->i_lock);
444 inode->i_blocks -= bytes >> 9;
445 bytes &= 511;
446 if (inode->i_bytes < bytes) {
447 inode->i_blocks--;
448 inode->i_bytes += 512;
449 }
450 inode->i_bytes -= bytes;
451 spin_unlock(&inode->i_lock);
452}
453
454EXPORT_SYMBOL(inode_sub_bytes);
455
456loff_t inode_get_bytes(struct inode *inode)
457{
458 loff_t ret;
459
460 spin_lock(&inode->i_lock);
461 ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
462 spin_unlock(&inode->i_lock);
463 return ret;
464}
465
466EXPORT_SYMBOL(inode_get_bytes);
467
468void inode_set_bytes(struct inode *inode, loff_t bytes)
469{
470 /* Caller is here responsible for sufficient locking
471 * (ie. inode->i_lock) */
472 inode->i_blocks = bytes >> 9;
473 inode->i_bytes = bytes & 511;
474}
475
476EXPORT_SYMBOL(inode_set_bytes);