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7#include <linux/module.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->atime = inode->i_atime;
31 stat->mtime = inode->i_mtime;
32 stat->ctime = inode->i_ctime;
33 stat->size = i_size_read(inode);
34 stat->blocks = inode->i_blocks;
35 stat->blksize = (1 << inode->i_blkbits);
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_stat_fd(int dfd, char __user *name, struct kstat *stat)
59{
60 struct path path;
61 int error;
62
63 error = user_path_at(dfd, name, LOOKUP_FOLLOW, &path);
64 if (!error) {
65 error = vfs_getattr(path.mnt, path.dentry, stat);
66 path_put(&path);
67 }
68 return error;
69}
70
71int vfs_stat(char __user *name, struct kstat *stat)
72{
73 return vfs_stat_fd(AT_FDCWD, name, stat);
74}
75
76EXPORT_SYMBOL(vfs_stat);
77
78int vfs_lstat_fd(int dfd, char __user *name, struct kstat *stat)
79{
80 struct path path;
81 int error;
82
83 error = user_path_at(dfd, name, 0, &path);
84 if (!error) {
85 error = vfs_getattr(path.mnt, path.dentry, stat);
86 path_put(&path);
87 }
88 return error;
89}
90
91int vfs_lstat(char __user *name, struct kstat *stat)
92{
93 return vfs_lstat_fd(AT_FDCWD, name, stat);
94}
95
96EXPORT_SYMBOL(vfs_lstat);
97
98int vfs_fstat(unsigned int fd, struct kstat *stat)
99{
100 struct file *f = fget(fd);
101 int error = -EBADF;
102
103 if (f) {
104 error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat);
105 fput(f);
106 }
107 return error;
108}
109
110EXPORT_SYMBOL(vfs_fstat);
111
112#ifdef __ARCH_WANT_OLD_STAT
113
114
115
116
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
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, stat->uid);
142 SET_GID(tmp.st_gid, 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, char __user *, filename, struct __old_kernel_stat __user *, statbuf)
156{
157 struct kstat stat;
158 int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
159
160 if (!error)
161 error = cp_old_stat(&stat, statbuf);
162
163 return error;
164}
165
166SYSCALL_DEFINE2(lstat, char __user *, filename, struct __old_kernel_stat __user *, statbuf)
167{
168 struct kstat stat;
169 int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
170
171 if (!error)
172 error = cp_old_stat(&stat, statbuf);
173
174 return error;
175}
176
177SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
178{
179 struct kstat stat;
180 int error = vfs_fstat(fd, &stat);
181
182 if (!error)
183 error = cp_old_stat(&stat, statbuf);
184
185 return error;
186}
187
188#endif
189
190static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
191{
192 struct stat tmp;
193
194#if BITS_PER_LONG == 32
195 if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
196 return -EOVERFLOW;
197#else
198 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
199 return -EOVERFLOW;
200#endif
201
202 memset(&tmp, 0, sizeof(tmp));
203#if BITS_PER_LONG == 32
204 tmp.st_dev = old_encode_dev(stat->dev);
205#else
206 tmp.st_dev = new_encode_dev(stat->dev);
207#endif
208 tmp.st_ino = stat->ino;
209 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
210 return -EOVERFLOW;
211 tmp.st_mode = stat->mode;
212 tmp.st_nlink = stat->nlink;
213 if (tmp.st_nlink != stat->nlink)
214 return -EOVERFLOW;
215 SET_UID(tmp.st_uid, stat->uid);
216 SET_GID(tmp.st_gid, stat->gid);
217#if BITS_PER_LONG == 32
218 tmp.st_rdev = old_encode_dev(stat->rdev);
219#else
220 tmp.st_rdev = new_encode_dev(stat->rdev);
221#endif
222#if BITS_PER_LONG == 32
223 if (stat->size > MAX_NON_LFS)
224 return -EOVERFLOW;
225#endif
226 tmp.st_size = stat->size;
227 tmp.st_atime = stat->atime.tv_sec;
228 tmp.st_mtime = stat->mtime.tv_sec;
229 tmp.st_ctime = stat->ctime.tv_sec;
230#ifdef STAT_HAVE_NSEC
231 tmp.st_atime_nsec = stat->atime.tv_nsec;
232 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
233 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
234#endif
235 tmp.st_blocks = stat->blocks;
236 tmp.st_blksize = stat->blksize;
237 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
238}
239
240SYSCALL_DEFINE2(newstat, char __user *, filename, struct stat __user *, statbuf)
241{
242 struct kstat stat;
243 int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
244
245 if (!error)
246 error = cp_new_stat(&stat, statbuf);
247
248 return error;
249}
250
251SYSCALL_DEFINE2(newlstat, char __user *, filename, struct stat __user *, statbuf)
252{
253 struct kstat stat;
254 int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
255
256 if (!error)
257 error = cp_new_stat(&stat, statbuf);
258
259 return error;
260}
261
262#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
263SYSCALL_DEFINE4(newfstatat, int, dfd, char __user *, filename,
264 struct stat __user *, statbuf, int, flag)
265{
266 struct kstat stat;
267 int error = -EINVAL;
268
269 if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
270 goto out;
271
272 if (flag & AT_SYMLINK_NOFOLLOW)
273 error = vfs_lstat_fd(dfd, filename, &stat);
274 else
275 error = vfs_stat_fd(dfd, filename, &stat);
276
277 if (!error)
278 error = cp_new_stat(&stat, statbuf);
279
280out:
281 return error;
282}
283#endif
284
285SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
286{
287 struct kstat stat;
288 int error = vfs_fstat(fd, &stat);
289
290 if (!error)
291 error = cp_new_stat(&stat, statbuf);
292
293 return error;
294}
295
296SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
297 char __user *, buf, int, bufsiz)
298{
299 struct path path;
300 int error;
301
302 if (bufsiz <= 0)
303 return -EINVAL;
304
305 error = user_path_at(dfd, pathname, 0, &path);
306 if (!error) {
307 struct inode *inode = path.dentry->d_inode;
308
309 error = -EINVAL;
310 if (inode->i_op->readlink) {
311 error = security_inode_readlink(path.dentry);
312 if (!error) {
313 touch_atime(path.mnt, path.dentry);
314 error = inode->i_op->readlink(path.dentry,
315 buf, bufsiz);
316 }
317 }
318 path_put(&path);
319 }
320 return error;
321}
322
323SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
324 int, bufsiz)
325{
326 return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
327}
328
329
330
331#ifdef __ARCH_WANT_STAT64
332
333static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
334{
335 struct stat64 tmp;
336
337 memset(&tmp, 0, sizeof(struct stat64));
338#ifdef CONFIG_MIPS
339
340 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
341 return -EOVERFLOW;
342 tmp.st_dev = new_encode_dev(stat->dev);
343 tmp.st_rdev = new_encode_dev(stat->rdev);
344#else
345 tmp.st_dev = huge_encode_dev(stat->dev);
346 tmp.st_rdev = huge_encode_dev(stat->rdev);
347#endif
348 tmp.st_ino = stat->ino;
349 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
350 return -EOVERFLOW;
351#ifdef STAT64_HAS_BROKEN_ST_INO
352 tmp.__st_ino = stat->ino;
353#endif
354 tmp.st_mode = stat->mode;
355 tmp.st_nlink = stat->nlink;
356 tmp.st_uid = stat->uid;
357 tmp.st_gid = stat->gid;
358 tmp.st_atime = stat->atime.tv_sec;
359 tmp.st_atime_nsec = stat->atime.tv_nsec;
360 tmp.st_mtime = stat->mtime.tv_sec;
361 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
362 tmp.st_ctime = stat->ctime.tv_sec;
363 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
364 tmp.st_size = stat->size;
365 tmp.st_blocks = stat->blocks;
366 tmp.st_blksize = stat->blksize;
367 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
368}
369
370SYSCALL_DEFINE2(stat64, char __user *, filename, struct stat64 __user *, statbuf)
371{
372 struct kstat stat;
373 int error = vfs_stat(filename, &stat);
374
375 if (!error)
376 error = cp_new_stat64(&stat, statbuf);
377
378 return error;
379}
380
381SYSCALL_DEFINE2(lstat64, char __user *, filename, struct stat64 __user *, statbuf)
382{
383 struct kstat stat;
384 int error = vfs_lstat(filename, &stat);
385
386 if (!error)
387 error = cp_new_stat64(&stat, statbuf);
388
389 return error;
390}
391
392SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
393{
394 struct kstat stat;
395 int error = vfs_fstat(fd, &stat);
396
397 if (!error)
398 error = cp_new_stat64(&stat, statbuf);
399
400 return error;
401}
402
403SYSCALL_DEFINE4(fstatat64, int, dfd, char __user *, filename,
404 struct stat64 __user *, statbuf, int, flag)
405{
406 struct kstat stat;
407 int error = -EINVAL;
408
409 if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
410 goto out;
411
412 if (flag & AT_SYMLINK_NOFOLLOW)
413 error = vfs_lstat_fd(dfd, filename, &stat);
414 else
415 error = vfs_stat_fd(dfd, filename, &stat);
416
417 if (!error)
418 error = cp_new_stat64(&stat, statbuf);
419
420out:
421 return error;
422}
423#endif
424
425void inode_add_bytes(struct inode *inode, loff_t bytes)
426{
427 spin_lock(&inode->i_lock);
428 inode->i_blocks += bytes >> 9;
429 bytes &= 511;
430 inode->i_bytes += bytes;
431 if (inode->i_bytes >= 512) {
432 inode->i_blocks++;
433 inode->i_bytes -= 512;
434 }
435 spin_unlock(&inode->i_lock);
436}
437
438EXPORT_SYMBOL(inode_add_bytes);
439
440void inode_sub_bytes(struct inode *inode, loff_t bytes)
441{
442 spin_lock(&inode->i_lock);
443 inode->i_blocks -= bytes >> 9;
444 bytes &= 511;
445 if (inode->i_bytes < bytes) {
446 inode->i_blocks--;
447 inode->i_bytes += 512;
448 }
449 inode->i_bytes -= bytes;
450 spin_unlock(&inode->i_lock);
451}
452
453EXPORT_SYMBOL(inode_sub_bytes);
454
455loff_t inode_get_bytes(struct inode *inode)
456{
457 loff_t ret;
458
459 spin_lock(&inode->i_lock);
460 ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
461 spin_unlock(&inode->i_lock);
462 return ret;
463}
464
465EXPORT_SYMBOL(inode_get_bytes);
466
467void inode_set_bytes(struct inode *inode, loff_t bytes)
468{
469
470
471 inode->i_blocks = bytes >> 9;
472 inode->i_bytes = bytes & 511;
473}
474
475EXPORT_SYMBOL(inode_set_bytes);
476
