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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 nameidata nd;
61 int error;
62
63 error = __user_walk_fd(dfd, name, LOOKUP_FOLLOW, &nd);
64 if (!error) {
65 error = vfs_getattr(nd.mnt, nd.dentry, stat);
66 path_release(&nd);
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 nameidata nd;
81 int error;
82
83 error = __user_walk_fd(dfd, name, 0, &nd);
84 if (!error) {
85 error = vfs_getattr(nd.mnt, nd.dentry, stat);
86 path_release(&nd);
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
155asmlinkage long sys_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}
165asmlinkage long sys_lstat(char __user * filename, struct __old_kernel_stat __user * statbuf)
166{
167 struct kstat stat;
168 int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
169
170 if (!error)
171 error = cp_old_stat(&stat, statbuf);
172
173 return error;
174}
175asmlinkage long sys_fstat(unsigned int fd, struct __old_kernel_stat __user * statbuf)
176{
177 struct kstat stat;
178 int error = vfs_fstat(fd, &stat);
179
180 if (!error)
181 error = cp_old_stat(&stat, statbuf);
182
183 return error;
184}
185
186#endif
187
188static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
189{
190 struct stat tmp;
191
192#if BITS_PER_LONG == 32
193 if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
194 return -EOVERFLOW;
195#else
196 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
197 return -EOVERFLOW;
198#endif
199
200 memset(&tmp, 0, sizeof(tmp));
201#if BITS_PER_LONG == 32
202 tmp.st_dev = old_encode_dev(stat->dev);
203#else
204 tmp.st_dev = new_encode_dev(stat->dev);
205#endif
206 tmp.st_ino = stat->ino;
207 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
208 return -EOVERFLOW;
209 tmp.st_mode = stat->mode;
210 tmp.st_nlink = stat->nlink;
211 if (tmp.st_nlink != stat->nlink)
212 return -EOVERFLOW;
213 SET_UID(tmp.st_uid, stat->uid);
214 SET_GID(tmp.st_gid, stat->gid);
215#if BITS_PER_LONG == 32
216 tmp.st_rdev = old_encode_dev(stat->rdev);
217#else
218 tmp.st_rdev = new_encode_dev(stat->rdev);
219#endif
220#if BITS_PER_LONG == 32
221 if (stat->size > MAX_NON_LFS)
222 return -EOVERFLOW;
223#endif
224 tmp.st_size = stat->size;
225 tmp.st_atime = stat->atime.tv_sec;
226 tmp.st_mtime = stat->mtime.tv_sec;
227 tmp.st_ctime = stat->ctime.tv_sec;
228#ifdef STAT_HAVE_NSEC
229 tmp.st_atime_nsec = stat->atime.tv_nsec;
230 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
231 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
232#endif
233 tmp.st_blocks = stat->blocks;
234 tmp.st_blksize = stat->blksize;
235 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
236}
237
238asmlinkage long sys_newstat(char __user *filename, struct stat __user *statbuf)
239{
240 struct kstat stat;
241 int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
242
243 if (!error)
244 error = cp_new_stat(&stat, statbuf);
245
246 return error;
247}
248
249asmlinkage long sys_newlstat(char __user *filename, struct stat __user *statbuf)
250{
251 struct kstat stat;
252 int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
253
254 if (!error)
255 error = cp_new_stat(&stat, statbuf);
256
257 return error;
258}
259
260#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
261asmlinkage long sys_newfstatat(int dfd, char __user *filename,
262 struct stat __user *statbuf, int flag)
263{
264 struct kstat stat;
265 int error = -EINVAL;
266
267 if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
268 goto out;
269
270 if (flag & AT_SYMLINK_NOFOLLOW)
271 error = vfs_lstat_fd(dfd, filename, &stat);
272 else
273 error = vfs_stat_fd(dfd, filename, &stat);
274
275 if (!error)
276 error = cp_new_stat(&stat, statbuf);
277
278out:
279 return error;
280}
281#endif
282
283asmlinkage long sys_newfstat(unsigned int fd, struct stat __user *statbuf)
284{
285 struct kstat stat;
286 int error = vfs_fstat(fd, &stat);
287
288 if (!error)
289 error = cp_new_stat(&stat, statbuf);
290
291 return error;
292}
293
294asmlinkage long sys_readlinkat(int dfd, const char __user *path,
295 char __user *buf, int bufsiz)
296{
297 struct nameidata nd;
298 int error;
299
300 if (bufsiz <= 0)
301 return -EINVAL;
302
303 error = __user_walk_fd(dfd, path, 0, &nd);
304 if (!error) {
305 struct inode * inode = nd.dentry->d_inode;
306
307 error = -EINVAL;
308 if (inode->i_op && inode->i_op->readlink) {
309 error = security_inode_readlink(nd.dentry);
310 if (!error) {
311 touch_atime(nd.mnt, nd.dentry);
312 error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
313 }
314 }
315 path_release(&nd);
316 }
317 return error;
318}
319
320asmlinkage long sys_readlink(const char __user *path, char __user *buf,
321 int bufsiz)
322{
323 return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
324}
325
326
327
328#ifdef __ARCH_WANT_STAT64
329
330static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
331{
332 struct stat64 tmp;
333
334 memset(&tmp, 0, sizeof(struct stat64));
335#ifdef CONFIG_MIPS
336
337 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
338 return -EOVERFLOW;
339 tmp.st_dev = new_encode_dev(stat->dev);
340 tmp.st_rdev = new_encode_dev(stat->rdev);
341#else
342 tmp.st_dev = huge_encode_dev(stat->dev);
343 tmp.st_rdev = huge_encode_dev(stat->rdev);
344#endif
345 tmp.st_ino = stat->ino;
346 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
347 return -EOVERFLOW;
348#ifdef STAT64_HAS_BROKEN_ST_INO
349 tmp.__st_ino = stat->ino;
350#endif
351 tmp.st_mode = stat->mode;
352 tmp.st_nlink = stat->nlink;
353 tmp.st_uid = stat->uid;
354 tmp.st_gid = stat->gid;
355 tmp.st_atime = stat->atime.tv_sec;
356 tmp.st_atime_nsec = stat->atime.tv_nsec;
357 tmp.st_mtime = stat->mtime.tv_sec;
358 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
359 tmp.st_ctime = stat->ctime.tv_sec;
360 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
361 tmp.st_size = stat->size;
362 tmp.st_blocks = stat->blocks;
363 tmp.st_blksize = stat->blksize;
364 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
365}
366
367asmlinkage long sys_stat64(char __user * filename, struct stat64 __user * statbuf)
368{
369 struct kstat stat;
370 int error = vfs_stat(filename, &stat);
371
372 if (!error)
373 error = cp_new_stat64(&stat, statbuf);
374
375 return error;
376}
377asmlinkage long sys_lstat64(char __user * filename, struct stat64 __user * statbuf)
378{
379 struct kstat stat;
380 int error = vfs_lstat(filename, &stat);
381
382 if (!error)
383 error = cp_new_stat64(&stat, statbuf);
384
385 return error;
386}
387asmlinkage long sys_fstat64(unsigned long fd, struct stat64 __user * statbuf)
388{
389 struct kstat stat;
390 int error = vfs_fstat(fd, &stat);
391
392 if (!error)
393 error = cp_new_stat64(&stat, statbuf);
394
395 return error;
396}
397
398asmlinkage long sys_fstatat64(int dfd, char __user *filename,
399 struct stat64 __user *statbuf, int flag)
400{
401 struct kstat stat;
402 int error = -EINVAL;
403
404 if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
405 goto out;
406
407 if (flag & AT_SYMLINK_NOFOLLOW)
408 error = vfs_lstat_fd(dfd, filename, &stat);
409 else
410 error = vfs_stat_fd(dfd, filename, &stat);
411
412 if (!error)
413 error = cp_new_stat64(&stat, statbuf);
414
415out:
416 return error;
417}
418#endif
419
420void inode_add_bytes(struct inode *inode, loff_t bytes)
421{
422 spin_lock(&inode->i_lock);
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 spin_unlock(&inode->i_lock);
431}
432
433EXPORT_SYMBOL(inode_add_bytes);
434
435void inode_sub_bytes(struct inode *inode, loff_t bytes)
436{
437 spin_lock(&inode->i_lock);
438 inode->i_blocks -= bytes >> 9;
439 bytes &= 511;
440 if (inode->i_bytes < bytes) {
441 inode->i_blocks--;
442 inode->i_bytes += 512;
443 }
444 inode->i_bytes -= bytes;
445 spin_unlock(&inode->i_lock);
446}
447
448EXPORT_SYMBOL(inode_sub_bytes);
449
450loff_t inode_get_bytes(struct inode *inode)
451{
452 loff_t ret;
453
454 spin_lock(&inode->i_lock);
455 ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
456 spin_unlock(&inode->i_lock);
457 return ret;
458}
459
460EXPORT_SYMBOL(inode_get_bytes);
461
462void inode_set_bytes(struct inode *inode, loff_t bytes)
463{
464
465
466 inode->i_blocks = bytes >> 9;
467 inode->i_bytes = bytes & 511;
468}
469
470EXPORT_SYMBOL(inode_set_bytes);
471
