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compat.c
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1 /*
2  * linux/fs/compat.c
3  *
4  * Kernel compatibililty routines for e.g. 32 bit syscall support
5  * on 64 bit kernels.
6  *
7  * Copyright (C) 2002 Stephen Rothwell, IBM Corporation
8  * Copyright (C) 1997-2000 Jakub Jelinek ([email protected])
9  * Copyright (C) 1998 Eddie C. Dost ([email protected])
10  * Copyright (C) 2001,2002 Andi Kleen, SuSE Labs
11  * Copyright (C) 2003 Pavel Machek ([email protected])
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License version 2 as
15  * published by the Free Software Foundation.
16  */
17 
18 #include <linux/stddef.h>
19 #include <linux/kernel.h>
20 #include <linux/linkage.h>
21 #include <linux/compat.h>
22 #include <linux/errno.h>
23 #include <linux/time.h>
24 #include <linux/fs.h>
25 #include <linux/fcntl.h>
26 #include <linux/namei.h>
27 #include <linux/file.h>
28 #include <linux/fdtable.h>
29 #include <linux/vfs.h>
30 #include <linux/ioctl.h>
31 #include <linux/init.h>
32 #include <linux/ncp_mount.h>
33 #include <linux/nfs4_mount.h>
34 #include <linux/syscalls.h>
35 #include <linux/ctype.h>
36 #include <linux/dirent.h>
37 #include <linux/fsnotify.h>
38 #include <linux/highuid.h>
39 #include <linux/personality.h>
40 #include <linux/rwsem.h>
41 #include <linux/tsacct_kern.h>
42 #include <linux/security.h>
43 #include <linux/highmem.h>
44 #include <linux/signal.h>
45 #include <linux/poll.h>
46 #include <linux/mm.h>
47 #include <linux/eventpoll.h>
48 #include <linux/fs_struct.h>
49 #include <linux/slab.h>
50 #include <linux/pagemap.h>
51 
52 #include <asm/uaccess.h>
53 #include <asm/mmu_context.h>
54 #include <asm/ioctls.h>
55 #include "internal.h"
56 
57 int compat_log = 1;
58 
59 int compat_printk(const char *fmt, ...)
60 {
61  va_list ap;
62  int ret;
63  if (!compat_log)
64  return 0;
65  va_start(ap, fmt);
66  ret = vprintk(fmt, ap);
67  va_end(ap);
68  return ret;
69 }
70 
71 #include "read_write.h"
72 
73 /*
74  * Not all architectures have sys_utime, so implement this in terms
75  * of sys_utimes.
76  */
77 asmlinkage long compat_sys_utime(const char __user *filename,
78  struct compat_utimbuf __user *t)
79 {
80  struct timespec tv[2];
81 
82  if (t) {
83  if (get_user(tv[0].tv_sec, &t->actime) ||
84  get_user(tv[1].tv_sec, &t->modtime))
85  return -EFAULT;
86  tv[0].tv_nsec = 0;
87  tv[1].tv_nsec = 0;
88  }
89  return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
90 }
91 
92 asmlinkage long compat_sys_utimensat(unsigned int dfd, const char __user *filename, struct compat_timespec __user *t, int flags)
93 {
94  struct timespec tv[2];
95 
96  if (t) {
97  if (get_compat_timespec(&tv[0], &t[0]) ||
98  get_compat_timespec(&tv[1], &t[1]))
99  return -EFAULT;
100 
101  if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
102  return 0;
103  }
104  return do_utimes(dfd, filename, t ? tv : NULL, flags);
105 }
106 
107 asmlinkage long compat_sys_futimesat(unsigned int dfd, const char __user *filename, struct compat_timeval __user *t)
108 {
109  struct timespec tv[2];
110 
111  if (t) {
112  if (get_user(tv[0].tv_sec, &t[0].tv_sec) ||
113  get_user(tv[0].tv_nsec, &t[0].tv_usec) ||
114  get_user(tv[1].tv_sec, &t[1].tv_sec) ||
115  get_user(tv[1].tv_nsec, &t[1].tv_usec))
116  return -EFAULT;
117  if (tv[0].tv_nsec >= 1000000 || tv[0].tv_nsec < 0 ||
118  tv[1].tv_nsec >= 1000000 || tv[1].tv_nsec < 0)
119  return -EINVAL;
120  tv[0].tv_nsec *= 1000;
121  tv[1].tv_nsec *= 1000;
122  }
123  return do_utimes(dfd, filename, t ? tv : NULL, 0);
124 }
125 
126 asmlinkage long compat_sys_utimes(const char __user *filename, struct compat_timeval __user *t)
127 {
128  return compat_sys_futimesat(AT_FDCWD, filename, t);
129 }
130 
131 static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
132 {
133  struct compat_stat tmp;
134 
135  if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
136  return -EOVERFLOW;
137 
138  memset(&tmp, 0, sizeof(tmp));
139  tmp.st_dev = old_encode_dev(stat->dev);
140  tmp.st_ino = stat->ino;
141  if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
142  return -EOVERFLOW;
143  tmp.st_mode = stat->mode;
144  tmp.st_nlink = stat->nlink;
145  if (tmp.st_nlink != stat->nlink)
146  return -EOVERFLOW;
147  SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
148  SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
149  tmp.st_rdev = old_encode_dev(stat->rdev);
150  if ((u64) stat->size > MAX_NON_LFS)
151  return -EOVERFLOW;
152  tmp.st_size = stat->size;
153  tmp.st_atime = stat->atime.tv_sec;
154  tmp.st_atime_nsec = stat->atime.tv_nsec;
155  tmp.st_mtime = stat->mtime.tv_sec;
156  tmp.st_mtime_nsec = stat->mtime.tv_nsec;
157  tmp.st_ctime = stat->ctime.tv_sec;
158  tmp.st_ctime_nsec = stat->ctime.tv_nsec;
159  tmp.st_blocks = stat->blocks;
160  tmp.st_blksize = stat->blksize;
161  return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
162 }
163 
164 asmlinkage long compat_sys_newstat(const char __user * filename,
165  struct compat_stat __user *statbuf)
166 {
167  struct kstat stat;
168  int error;
169 
170  error = vfs_stat(filename, &stat);
171  if (error)
172  return error;
173  return cp_compat_stat(&stat, statbuf);
174 }
175 
176 asmlinkage long compat_sys_newlstat(const char __user * filename,
177  struct compat_stat __user *statbuf)
178 {
179  struct kstat stat;
180  int error;
181 
182  error = vfs_lstat(filename, &stat);
183  if (error)
184  return error;
185  return cp_compat_stat(&stat, statbuf);
186 }
187 
188 #ifndef __ARCH_WANT_STAT64
189 asmlinkage long compat_sys_newfstatat(unsigned int dfd,
190  const char __user *filename,
191  struct compat_stat __user *statbuf, int flag)
192 {
193  struct kstat stat;
194  int error;
195 
196  error = vfs_fstatat(dfd, filename, &stat, flag);
197  if (error)
198  return error;
199  return cp_compat_stat(&stat, statbuf);
200 }
201 #endif
202 
203 asmlinkage long compat_sys_newfstat(unsigned int fd,
204  struct compat_stat __user * statbuf)
205 {
206  struct kstat stat;
207  int error = vfs_fstat(fd, &stat);
208 
209  if (!error)
210  error = cp_compat_stat(&stat, statbuf);
211  return error;
212 }
213 
214 static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf)
215 {
216 
217  if (sizeof ubuf->f_blocks == 4) {
218  if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
219  kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
220  return -EOVERFLOW;
221  /* f_files and f_ffree may be -1; it's okay
222  * to stuff that into 32 bits */
223  if (kbuf->f_files != 0xffffffffffffffffULL
224  && (kbuf->f_files & 0xffffffff00000000ULL))
225  return -EOVERFLOW;
226  if (kbuf->f_ffree != 0xffffffffffffffffULL
227  && (kbuf->f_ffree & 0xffffffff00000000ULL))
228  return -EOVERFLOW;
229  }
230  if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
231  __put_user(kbuf->f_type, &ubuf->f_type) ||
232  __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
233  __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
234  __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
235  __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
236  __put_user(kbuf->f_files, &ubuf->f_files) ||
237  __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
238  __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
239  __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
240  __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
241  __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
242  __put_user(kbuf->f_flags, &ubuf->f_flags) ||
243  __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))
244  return -EFAULT;
245  return 0;
246 }
247 
248 /*
249  * The following statfs calls are copies of code from fs/statfs.c and
250  * should be checked against those from time to time
251  */
252 asmlinkage long compat_sys_statfs(const char __user *pathname, struct compat_statfs __user *buf)
253 {
254  struct kstatfs tmp;
255  int error = user_statfs(pathname, &tmp);
256  if (!error)
257  error = put_compat_statfs(buf, &tmp);
258  return error;
259 }
260 
261 asmlinkage long compat_sys_fstatfs(unsigned int fd, struct compat_statfs __user *buf)
262 {
263  struct kstatfs tmp;
264  int error = fd_statfs(fd, &tmp);
265  if (!error)
266  error = put_compat_statfs(buf, &tmp);
267  return error;
268 }
269 
270 static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf)
271 {
272  if (sizeof ubuf->f_blocks == 4) {
273  if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
274  kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
275  return -EOVERFLOW;
276  /* f_files and f_ffree may be -1; it's okay
277  * to stuff that into 32 bits */
278  if (kbuf->f_files != 0xffffffffffffffffULL
279  && (kbuf->f_files & 0xffffffff00000000ULL))
280  return -EOVERFLOW;
281  if (kbuf->f_ffree != 0xffffffffffffffffULL
282  && (kbuf->f_ffree & 0xffffffff00000000ULL))
283  return -EOVERFLOW;
284  }
285  if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
286  __put_user(kbuf->f_type, &ubuf->f_type) ||
287  __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
288  __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
289  __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
290  __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
291  __put_user(kbuf->f_files, &ubuf->f_files) ||
292  __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
293  __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
294  __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
295  __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
296  __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
297  __put_user(kbuf->f_flags, &ubuf->f_flags) ||
298  __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))
299  return -EFAULT;
300  return 0;
301 }
302 
303 asmlinkage long compat_sys_statfs64(const char __user *pathname, compat_size_t sz, struct compat_statfs64 __user *buf)
304 {
305  struct kstatfs tmp;
306  int error;
307 
308  if (sz != sizeof(*buf))
309  return -EINVAL;
310 
311  error = user_statfs(pathname, &tmp);
312  if (!error)
313  error = put_compat_statfs64(buf, &tmp);
314  return error;
315 }
316 
317 asmlinkage long compat_sys_fstatfs64(unsigned int fd, compat_size_t sz, struct compat_statfs64 __user *buf)
318 {
319  struct kstatfs tmp;
320  int error;
321 
322  if (sz != sizeof(*buf))
323  return -EINVAL;
324 
325  error = fd_statfs(fd, &tmp);
326  if (!error)
327  error = put_compat_statfs64(buf, &tmp);
328  return error;
329 }
330 
331 /*
332  * This is a copy of sys_ustat, just dealing with a structure layout.
333  * Given how simple this syscall is that apporach is more maintainable
334  * than the various conversion hacks.
335  */
336 asmlinkage long compat_sys_ustat(unsigned dev, struct compat_ustat __user *u)
337 {
338  struct compat_ustat tmp;
339  struct kstatfs sbuf;
340  int err = vfs_ustat(new_decode_dev(dev), &sbuf);
341  if (err)
342  return err;
343 
344  memset(&tmp, 0, sizeof(struct compat_ustat));
345  tmp.f_tfree = sbuf.f_bfree;
346  tmp.f_tinode = sbuf.f_ffree;
347  if (copy_to_user(u, &tmp, sizeof(struct compat_ustat)))
348  return -EFAULT;
349  return 0;
350 }
351 
352 static int get_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
353 {
354  if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
355  __get_user(kfl->l_type, &ufl->l_type) ||
356  __get_user(kfl->l_whence, &ufl->l_whence) ||
357  __get_user(kfl->l_start, &ufl->l_start) ||
358  __get_user(kfl->l_len, &ufl->l_len) ||
359  __get_user(kfl->l_pid, &ufl->l_pid))
360  return -EFAULT;
361  return 0;
362 }
363 
364 static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
365 {
366  if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
367  __put_user(kfl->l_type, &ufl->l_type) ||
368  __put_user(kfl->l_whence, &ufl->l_whence) ||
369  __put_user(kfl->l_start, &ufl->l_start) ||
370  __put_user(kfl->l_len, &ufl->l_len) ||
371  __put_user(kfl->l_pid, &ufl->l_pid))
372  return -EFAULT;
373  return 0;
374 }
375 
376 #ifndef HAVE_ARCH_GET_COMPAT_FLOCK64
377 static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
378 {
379  if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
380  __get_user(kfl->l_type, &ufl->l_type) ||
381  __get_user(kfl->l_whence, &ufl->l_whence) ||
382  __get_user(kfl->l_start, &ufl->l_start) ||
383  __get_user(kfl->l_len, &ufl->l_len) ||
384  __get_user(kfl->l_pid, &ufl->l_pid))
385  return -EFAULT;
386  return 0;
387 }
388 #endif
389 
390 #ifndef HAVE_ARCH_PUT_COMPAT_FLOCK64
391 static int put_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
392 {
393  if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
394  __put_user(kfl->l_type, &ufl->l_type) ||
395  __put_user(kfl->l_whence, &ufl->l_whence) ||
396  __put_user(kfl->l_start, &ufl->l_start) ||
397  __put_user(kfl->l_len, &ufl->l_len) ||
398  __put_user(kfl->l_pid, &ufl->l_pid))
399  return -EFAULT;
400  return 0;
401 }
402 #endif
403 
404 asmlinkage long compat_sys_fcntl64(unsigned int fd, unsigned int cmd,
405  unsigned long arg)
406 {
407  mm_segment_t old_fs;
408  struct flock f;
409  long ret;
410 
411  switch (cmd) {
412  case F_GETLK:
413  case F_SETLK:
414  case F_SETLKW:
415  ret = get_compat_flock(&f, compat_ptr(arg));
416  if (ret != 0)
417  break;
418  old_fs = get_fs();
419  set_fs(KERNEL_DS);
420  ret = sys_fcntl(fd, cmd, (unsigned long)&f);
421  set_fs(old_fs);
422  if (cmd == F_GETLK && ret == 0) {
423  /* GETLK was successful and we need to return the data...
424  * but it needs to fit in the compat structure.
425  * l_start shouldn't be too big, unless the original
426  * start + end is greater than COMPAT_OFF_T_MAX, in which
427  * case the app was asking for trouble, so we return
428  * -EOVERFLOW in that case.
429  * l_len could be too big, in which case we just truncate it,
430  * and only allow the app to see that part of the conflicting
431  * lock that might make sense to it anyway
432  */
433 
434  if (f.l_start > COMPAT_OFF_T_MAX)
435  ret = -EOVERFLOW;
436  if (f.l_len > COMPAT_OFF_T_MAX)
437  f.l_len = COMPAT_OFF_T_MAX;
438  if (ret == 0)
439  ret = put_compat_flock(&f, compat_ptr(arg));
440  }
441  break;
442 
443  case F_GETLK64:
444  case F_SETLK64:
445  case F_SETLKW64:
446  ret = get_compat_flock64(&f, compat_ptr(arg));
447  if (ret != 0)
448  break;
449  old_fs = get_fs();
450  set_fs(KERNEL_DS);
451  ret = sys_fcntl(fd, (cmd == F_GETLK64) ? F_GETLK :
452  ((cmd == F_SETLK64) ? F_SETLK : F_SETLKW),
453  (unsigned long)&f);
454  set_fs(old_fs);
455  if (cmd == F_GETLK64 && ret == 0) {
456  /* need to return lock information - see above for commentary */
457  if (f.l_start > COMPAT_LOFF_T_MAX)
458  ret = -EOVERFLOW;
459  if (f.l_len > COMPAT_LOFF_T_MAX)
460  f.l_len = COMPAT_LOFF_T_MAX;
461  if (ret == 0)
462  ret = put_compat_flock64(&f, compat_ptr(arg));
463  }
464  break;
465 
466  default:
467  ret = sys_fcntl(fd, cmd, arg);
468  break;
469  }
470  return ret;
471 }
472 
473 asmlinkage long compat_sys_fcntl(unsigned int fd, unsigned int cmd,
474  unsigned long arg)
475 {
476  if ((cmd == F_GETLK64) || (cmd == F_SETLK64) || (cmd == F_SETLKW64))
477  return -EINVAL;
478  return compat_sys_fcntl64(fd, cmd, arg);
479 }
480 
481 asmlinkage long
482 compat_sys_io_setup(unsigned nr_reqs, u32 __user *ctx32p)
483 {
484  long ret;
485  aio_context_t ctx64;
486 
487  mm_segment_t oldfs = get_fs();
488  if (unlikely(get_user(ctx64, ctx32p)))
489  return -EFAULT;
490 
491  set_fs(KERNEL_DS);
492  /* The __user pointer cast is valid because of the set_fs() */
493  ret = sys_io_setup(nr_reqs, (aio_context_t __user *) &ctx64);
494  set_fs(oldfs);
495  /* truncating is ok because it's a user address */
496  if (!ret)
497  ret = put_user((u32) ctx64, ctx32p);
498  return ret;
499 }
500 
501 asmlinkage long
502 compat_sys_io_getevents(aio_context_t ctx_id,
503  unsigned long min_nr,
504  unsigned long nr,
505  struct io_event __user *events,
506  struct compat_timespec __user *timeout)
507 {
508  long ret;
509  struct timespec t;
510  struct timespec __user *ut = NULL;
511 
512  ret = -EFAULT;
513  if (unlikely(!access_ok(VERIFY_WRITE, events,
514  nr * sizeof(struct io_event))))
515  goto out;
516  if (timeout) {
517  if (get_compat_timespec(&t, timeout))
518  goto out;
519 
520  ut = compat_alloc_user_space(sizeof(*ut));
521  if (copy_to_user(ut, &t, sizeof(t)) )
522  goto out;
523  }
524  ret = sys_io_getevents(ctx_id, min_nr, nr, events, ut);
525 out:
526  return ret;
527 }
528 
529 /* A write operation does a read from user space and vice versa */
530 #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
531 
532 ssize_t compat_rw_copy_check_uvector(int type,
533  const struct compat_iovec __user *uvector, unsigned long nr_segs,
534  unsigned long fast_segs, struct iovec *fast_pointer,
535  struct iovec **ret_pointer)
536 {
537  compat_ssize_t tot_len;
538  struct iovec *iov = *ret_pointer = fast_pointer;
539  ssize_t ret = 0;
540  int seg;
541 
542  /*
543  * SuS says "The readv() function *may* fail if the iovcnt argument
544  * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
545  * traditionally returned zero for zero segments, so...
546  */
547  if (nr_segs == 0)
548  goto out;
549 
550  ret = -EINVAL;
551  if (nr_segs > UIO_MAXIOV || nr_segs < 0)
552  goto out;
553  if (nr_segs > fast_segs) {
554  ret = -ENOMEM;
555  iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
556  if (iov == NULL)
557  goto out;
558  }
559  *ret_pointer = iov;
560 
561  /*
562  * Single unix specification:
563  * We should -EINVAL if an element length is not >= 0 and fitting an
564  * ssize_t.
565  *
566  * In Linux, the total length is limited to MAX_RW_COUNT, there is
567  * no overflow possibility.
568  */
569  tot_len = 0;
570  ret = -EINVAL;
571  for (seg = 0; seg < nr_segs; seg++) {
572  compat_uptr_t buf;
573  compat_ssize_t len;
574 
575  if (__get_user(len, &uvector->iov_len) ||
576  __get_user(buf, &uvector->iov_base)) {
577  ret = -EFAULT;
578  goto out;
579  }
580  if (len < 0) /* size_t not fitting in compat_ssize_t .. */
581  goto out;
582  if (type >= 0 &&
583  !access_ok(vrfy_dir(type), compat_ptr(buf), len)) {
584  ret = -EFAULT;
585  goto out;
586  }
587  if (len > MAX_RW_COUNT - tot_len)
588  len = MAX_RW_COUNT - tot_len;
589  tot_len += len;
590  iov->iov_base = compat_ptr(buf);
591  iov->iov_len = (compat_size_t) len;
592  uvector++;
593  iov++;
594  }
595  ret = tot_len;
596 
597 out:
598  return ret;
599 }
600 
601 static inline long
602 copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64)
603 {
604  compat_uptr_t uptr;
605  int i;
606 
607  for (i = 0; i < nr; ++i) {
608  if (get_user(uptr, ptr32 + i))
609  return -EFAULT;
610  if (put_user(compat_ptr(uptr), ptr64 + i))
611  return -EFAULT;
612  }
613  return 0;
614 }
615 
616 #define MAX_AIO_SUBMITS (PAGE_SIZE/sizeof(struct iocb *))
617 
618 asmlinkage long
619 compat_sys_io_submit(aio_context_t ctx_id, int nr, u32 __user *iocb)
620 {
621  struct iocb __user * __user *iocb64;
622  long ret;
623 
624  if (unlikely(nr < 0))
625  return -EINVAL;
626 
627  if (nr > MAX_AIO_SUBMITS)
628  nr = MAX_AIO_SUBMITS;
629 
630  iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64));
631  ret = copy_iocb(nr, iocb, iocb64);
632  if (!ret)
633  ret = do_io_submit(ctx_id, nr, iocb64, 1);
634  return ret;
635 }
636 
637 struct compat_ncp_mount_data {
638  compat_int_t version;
639  compat_uint_t ncp_fd;
640  __compat_uid_t mounted_uid;
641  compat_pid_t wdog_pid;
642  unsigned char mounted_vol[NCP_VOLNAME_LEN + 1];
643  compat_uint_t time_out;
644  compat_uint_t retry_count;
645  compat_uint_t flags;
646  __compat_uid_t uid;
647  __compat_gid_t gid;
648  compat_mode_t file_mode;
649  compat_mode_t dir_mode;
650 };
651 
652 struct compat_ncp_mount_data_v4 {
653  compat_int_t version;
654  compat_ulong_t flags;
655  compat_ulong_t mounted_uid;
656  compat_long_t wdog_pid;
657  compat_uint_t ncp_fd;
658  compat_uint_t time_out;
659  compat_uint_t retry_count;
660  compat_ulong_t uid;
661  compat_ulong_t gid;
662  compat_ulong_t file_mode;
663  compat_ulong_t dir_mode;
664 };
665 
666 static void *do_ncp_super_data_conv(void *raw_data)
667 {
668  int version = *(unsigned int *)raw_data;
669 
670  if (version == 3) {
671  struct compat_ncp_mount_data *c_n = raw_data;
672  struct ncp_mount_data *n = raw_data;
673 
674  n->dir_mode = c_n->dir_mode;
675  n->file_mode = c_n->file_mode;
676  n->gid = c_n->gid;
677  n->uid = c_n->uid;
678  memmove (n->mounted_vol, c_n->mounted_vol, (sizeof (c_n->mounted_vol) + 3 * sizeof (unsigned int)));
679  n->wdog_pid = c_n->wdog_pid;
680  n->mounted_uid = c_n->mounted_uid;
681  } else if (version == 4) {
682  struct compat_ncp_mount_data_v4 *c_n = raw_data;
683  struct ncp_mount_data_v4 *n = raw_data;
684 
685  n->dir_mode = c_n->dir_mode;
686  n->file_mode = c_n->file_mode;
687  n->gid = c_n->gid;
688  n->uid = c_n->uid;
689  n->retry_count = c_n->retry_count;
690  n->time_out = c_n->time_out;
691  n->ncp_fd = c_n->ncp_fd;
692  n->wdog_pid = c_n->wdog_pid;
693  n->mounted_uid = c_n->mounted_uid;
694  n->flags = c_n->flags;
695  } else if (version != 5) {
696  return NULL;
697  }
698 
699  return raw_data;
700 }
701 
702 
703 struct compat_nfs_string {
704  compat_uint_t len;
705  compat_uptr_t data;
706 };
707 
708 static inline void compat_nfs_string(struct nfs_string *dst,
709  struct compat_nfs_string *src)
710 {
711  dst->data = compat_ptr(src->data);
712  dst->len = src->len;
713 }
714 
715 struct compat_nfs4_mount_data_v1 {
716  compat_int_t version;
717  compat_int_t flags;
718  compat_int_t rsize;
719  compat_int_t wsize;
720  compat_int_t timeo;
721  compat_int_t retrans;
722  compat_int_t acregmin;
723  compat_int_t acregmax;
724  compat_int_t acdirmin;
725  compat_int_t acdirmax;
726  struct compat_nfs_string client_addr;
727  struct compat_nfs_string mnt_path;
728  struct compat_nfs_string hostname;
729  compat_uint_t host_addrlen;
730  compat_uptr_t host_addr;
731  compat_int_t proto;
732  compat_int_t auth_flavourlen;
733  compat_uptr_t auth_flavours;
734 };
735 
736 static int do_nfs4_super_data_conv(void *raw_data)
737 {
738  int version = *(compat_uint_t *) raw_data;
739 
740  if (version == 1) {
741  struct compat_nfs4_mount_data_v1 *raw = raw_data;
742  struct nfs4_mount_data *real = raw_data;
743 
744  /* copy the fields backwards */
745  real->auth_flavours = compat_ptr(raw->auth_flavours);
746  real->auth_flavourlen = raw->auth_flavourlen;
747  real->proto = raw->proto;
748  real->host_addr = compat_ptr(raw->host_addr);
749  real->host_addrlen = raw->host_addrlen;
750  compat_nfs_string(&real->hostname, &raw->hostname);
751  compat_nfs_string(&real->mnt_path, &raw->mnt_path);
752  compat_nfs_string(&real->client_addr, &raw->client_addr);
753  real->acdirmax = raw->acdirmax;
754  real->acdirmin = raw->acdirmin;
755  real->acregmax = raw->acregmax;
756  real->acregmin = raw->acregmin;
757  real->retrans = raw->retrans;
758  real->timeo = raw->timeo;
759  real->wsize = raw->wsize;
760  real->rsize = raw->rsize;
761  real->flags = raw->flags;
762  real->version = raw->version;
763  }
764 
765  return 0;
766 }
767 
768 #define NCPFS_NAME "ncpfs"
769 #define NFS4_NAME "nfs4"
770 
771 asmlinkage long compat_sys_mount(const char __user * dev_name,
772  const char __user * dir_name,
773  const char __user * type, unsigned long flags,
774  const void __user * data)
775 {
776  char *kernel_type;
777  unsigned long data_page;
778  char *kernel_dev;
779  struct filename *dir;
780  int retval;
781 
782  retval = copy_mount_string(type, &kernel_type);
783  if (retval < 0)
784  goto out;
785 
786  dir = getname(dir_name);
787  retval = PTR_ERR(dir);
788  if (IS_ERR(dir))
789  goto out1;
790 
791  retval = copy_mount_string(dev_name, &kernel_dev);
792  if (retval < 0)
793  goto out2;
794 
795  retval = copy_mount_options(data, &data_page);
796  if (retval < 0)
797  goto out3;
798 
799  retval = -EINVAL;
800 
801  if (kernel_type && data_page) {
802  if (!strcmp(kernel_type, NCPFS_NAME)) {
803  do_ncp_super_data_conv((void *)data_page);
804  } else if (!strcmp(kernel_type, NFS4_NAME)) {
805  if (do_nfs4_super_data_conv((void *) data_page))
806  goto out4;
807  }
808  }
809 
810  retval = do_mount(kernel_dev, dir->name, kernel_type,
811  flags, (void*)data_page);
812 
813  out4:
814  free_page(data_page);
815  out3:
816  kfree(kernel_dev);
817  out2:
818  putname(dir);
819  out1:
820  kfree(kernel_type);
821  out:
822  return retval;
823 }
824 
825 struct compat_old_linux_dirent {
826  compat_ulong_t d_ino;
827  compat_ulong_t d_offset;
828  unsigned short d_namlen;
829  char d_name[1];
830 };
831 
832 struct compat_readdir_callback {
833  struct compat_old_linux_dirent __user *dirent;
834  int result;
835 };
836 
837 static int compat_fillonedir(void *__buf, const char *name, int namlen,
838  loff_t offset, u64 ino, unsigned int d_type)
839 {
840  struct compat_readdir_callback *buf = __buf;
841  struct compat_old_linux_dirent __user *dirent;
842  compat_ulong_t d_ino;
843 
844  if (buf->result)
845  return -EINVAL;
846  d_ino = ino;
847  if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
848  buf->result = -EOVERFLOW;
849  return -EOVERFLOW;
850  }
851  buf->result++;
852  dirent = buf->dirent;
853  if (!access_ok(VERIFY_WRITE, dirent,
854  (unsigned long)(dirent->d_name + namlen + 1) -
855  (unsigned long)dirent))
856  goto efault;
857  if ( __put_user(d_ino, &dirent->d_ino) ||
858  __put_user(offset, &dirent->d_offset) ||
859  __put_user(namlen, &dirent->d_namlen) ||
860  __copy_to_user(dirent->d_name, name, namlen) ||
861  __put_user(0, dirent->d_name + namlen))
862  goto efault;
863  return 0;
864 efault:
865  buf->result = -EFAULT;
866  return -EFAULT;
867 }
868 
869 asmlinkage long compat_sys_old_readdir(unsigned int fd,
870  struct compat_old_linux_dirent __user *dirent, unsigned int count)
871 {
872  int error;
873  struct fd f = fdget(fd);
874  struct compat_readdir_callback buf;
875 
876  if (!f.file)
877  return -EBADF;
878 
879  buf.result = 0;
880  buf.dirent = dirent;
881 
882  error = vfs_readdir(f.file, compat_fillonedir, &buf);
883  if (buf.result)
884  error = buf.result;
885 
886  fdput(f);
887  return error;
888 }
889 
890 struct compat_linux_dirent {
891  compat_ulong_t d_ino;
892  compat_ulong_t d_off;
893  unsigned short d_reclen;
894  char d_name[1];
895 };
896 
897 struct compat_getdents_callback {
898  struct compat_linux_dirent __user *current_dir;
899  struct compat_linux_dirent __user *previous;
900  int count;
901  int error;
902 };
903 
904 static int compat_filldir(void *__buf, const char *name, int namlen,
905  loff_t offset, u64 ino, unsigned int d_type)
906 {
907  struct compat_linux_dirent __user * dirent;
908  struct compat_getdents_callback *buf = __buf;
909  compat_ulong_t d_ino;
910  int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) +
911  namlen + 2, sizeof(compat_long_t));
912 
913  buf->error = -EINVAL; /* only used if we fail.. */
914  if (reclen > buf->count)
915  return -EINVAL;
916  d_ino = ino;
917  if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
918  buf->error = -EOVERFLOW;
919  return -EOVERFLOW;
920  }
921  dirent = buf->previous;
922  if (dirent) {
923  if (__put_user(offset, &dirent->d_off))
924  goto efault;
925  }
926  dirent = buf->current_dir;
927  if (__put_user(d_ino, &dirent->d_ino))
928  goto efault;
929  if (__put_user(reclen, &dirent->d_reclen))
930  goto efault;
931  if (copy_to_user(dirent->d_name, name, namlen))
932  goto efault;
933  if (__put_user(0, dirent->d_name + namlen))
934  goto efault;
935  if (__put_user(d_type, (char __user *) dirent + reclen - 1))
936  goto efault;
937  buf->previous = dirent;
938  dirent = (void __user *)dirent + reclen;
939  buf->current_dir = dirent;
940  buf->count -= reclen;
941  return 0;
942 efault:
943  buf->error = -EFAULT;
944  return -EFAULT;
945 }
946 
947 asmlinkage long compat_sys_getdents(unsigned int fd,
948  struct compat_linux_dirent __user *dirent, unsigned int count)
949 {
950  struct fd f;
951  struct compat_linux_dirent __user * lastdirent;
952  struct compat_getdents_callback buf;
953  int error;
954 
955  if (!access_ok(VERIFY_WRITE, dirent, count))
956  return -EFAULT;
957 
958  f = fdget(fd);
959  if (!f.file)
960  return -EBADF;
961 
962  buf.current_dir = dirent;
963  buf.previous = NULL;
964  buf.count = count;
965  buf.error = 0;
966 
967  error = vfs_readdir(f.file, compat_filldir, &buf);
968  if (error >= 0)
969  error = buf.error;
970  lastdirent = buf.previous;
971  if (lastdirent) {
972  if (put_user(f.file->f_pos, &lastdirent->d_off))
973  error = -EFAULT;
974  else
975  error = count - buf.count;
976  }
977  fdput(f);
978  return error;
979 }
980 
981 #ifndef __ARCH_OMIT_COMPAT_SYS_GETDENTS64
982 
983 struct compat_getdents_callback64 {
984  struct linux_dirent64 __user *current_dir;
985  struct linux_dirent64 __user *previous;
986  int count;
987  int error;
988 };
989 
990 static int compat_filldir64(void * __buf, const char * name, int namlen, loff_t offset,
991  u64 ino, unsigned int d_type)
992 {
993  struct linux_dirent64 __user *dirent;
994  struct compat_getdents_callback64 *buf = __buf;
995  int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,
996  sizeof(u64));
997  u64 off;
998 
999  buf->error = -EINVAL; /* only used if we fail.. */
1000  if (reclen > buf->count)
1001  return -EINVAL;
1002  dirent = buf->previous;
1003 
1004  if (dirent) {
1005  if (__put_user_unaligned(offset, &dirent->d_off))
1006  goto efault;
1007  }
1008  dirent = buf->current_dir;
1009  if (__put_user_unaligned(ino, &dirent->d_ino))
1010  goto efault;
1011  off = 0;
1012  if (__put_user_unaligned(off, &dirent->d_off))
1013  goto efault;
1014  if (__put_user(reclen, &dirent->d_reclen))
1015  goto efault;
1016  if (__put_user(d_type, &dirent->d_type))
1017  goto efault;
1018  if (copy_to_user(dirent->d_name, name, namlen))
1019  goto efault;
1020  if (__put_user(0, dirent->d_name + namlen))
1021  goto efault;
1022  buf->previous = dirent;
1023  dirent = (void __user *)dirent + reclen;
1024  buf->current_dir = dirent;
1025  buf->count -= reclen;
1026  return 0;
1027 efault:
1028  buf->error = -EFAULT;
1029  return -EFAULT;
1030 }
1031 
1032 asmlinkage long compat_sys_getdents64(unsigned int fd,
1033  struct linux_dirent64 __user * dirent, unsigned int count)
1034 {
1035  struct fd f;
1036  struct linux_dirent64 __user * lastdirent;
1037  struct compat_getdents_callback64 buf;
1038  int error;
1039 
1040  if (!access_ok(VERIFY_WRITE, dirent, count))
1041  return -EFAULT;
1042 
1043  f = fdget(fd);
1044  if (!f.file)
1045  return -EBADF;
1046 
1047  buf.current_dir = dirent;
1048  buf.previous = NULL;
1049  buf.count = count;
1050  buf.error = 0;
1051 
1052  error = vfs_readdir(f.file, compat_filldir64, &buf);
1053  if (error >= 0)
1054  error = buf.error;
1055  lastdirent = buf.previous;
1056  if (lastdirent) {
1057  typeof(lastdirent->d_off) d_off = f.file->f_pos;
1058  if (__put_user_unaligned(d_off, &lastdirent->d_off))
1059  error = -EFAULT;
1060  else
1061  error = count - buf.count;
1062  }
1063  fdput(f);
1064  return error;
1065 }
1066 #endif /* ! __ARCH_OMIT_COMPAT_SYS_GETDENTS64 */
1067 
1068 static ssize_t compat_do_readv_writev(int type, struct file *file,
1069  const struct compat_iovec __user *uvector,
1070  unsigned long nr_segs, loff_t *pos)
1071 {
1072  compat_ssize_t tot_len;
1073  struct iovec iovstack[UIO_FASTIOV];
1074  struct iovec *iov = iovstack;
1075  ssize_t ret;
1076  io_fn_t fn;
1077  iov_fn_t fnv;
1078 
1079  ret = -EINVAL;
1080  if (!file->f_op)
1081  goto out;
1082 
1083  ret = -EFAULT;
1084  if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
1085  goto out;
1086 
1087  tot_len = compat_rw_copy_check_uvector(type, uvector, nr_segs,
1088  UIO_FASTIOV, iovstack, &iov);
1089  if (tot_len == 0) {
1090  ret = 0;
1091  goto out;
1092  }
1093 
1094  ret = rw_verify_area(type, file, pos, tot_len);
1095  if (ret < 0)
1096  goto out;
1097 
1098  fnv = NULL;
1099  if (type == READ) {
1100  fn = file->f_op->read;
1101  fnv = file->f_op->aio_read;
1102  } else {
1103  fn = (io_fn_t)file->f_op->write;
1104  fnv = file->f_op->aio_write;
1105  }
1106 
1107  if (fnv)
1108  ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
1109  pos, fnv);
1110  else
1111  ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
1112 
1113 out:
1114  if (iov != iovstack)
1115  kfree(iov);
1116  if ((ret + (type == READ)) > 0) {
1117  if (type == READ)
1118  fsnotify_access(file);
1119  else
1120  fsnotify_modify(file);
1121  }
1122  return ret;
1123 }
1124 
1125 static size_t compat_readv(struct file *file,
1126  const struct compat_iovec __user *vec,
1127  unsigned long vlen, loff_t *pos)
1128 {
1129  ssize_t ret = -EBADF;
1130 
1131  if (!(file->f_mode & FMODE_READ))
1132  goto out;
1133 
1134  ret = -EINVAL;
1135  if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read))
1136  goto out;
1137 
1138  ret = compat_do_readv_writev(READ, file, vec, vlen, pos);
1139 
1140 out:
1141  if (ret > 0)
1142  add_rchar(current, ret);
1143  inc_syscr(current);
1144  return ret;
1145 }
1146 
1147 asmlinkage ssize_t
1148 compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec,
1149  unsigned long vlen)
1150 {
1151  struct fd f = fdget(fd);
1152  ssize_t ret;
1153  loff_t pos;
1154 
1155  if (!f.file)
1156  return -EBADF;
1157  pos = f.file->f_pos;
1158  ret = compat_readv(f.file, vec, vlen, &pos);
1159  f.file->f_pos = pos;
1160  fdput(f);
1161  return ret;
1162 }
1163 
1164 asmlinkage ssize_t
1165 compat_sys_preadv64(unsigned long fd, const struct compat_iovec __user *vec,
1166  unsigned long vlen, loff_t pos)
1167 {
1168  struct fd f;
1169  ssize_t ret;
1170 
1171  if (pos < 0)
1172  return -EINVAL;
1173  f = fdget(fd);
1174  if (!f.file)
1175  return -EBADF;
1176  ret = -ESPIPE;
1177  if (f.file->f_mode & FMODE_PREAD)
1178  ret = compat_readv(f.file, vec, vlen, &pos);
1179  fdput(f);
1180  return ret;
1181 }
1182 
1183 asmlinkage ssize_t
1184 compat_sys_preadv(unsigned long fd, const struct compat_iovec __user *vec,
1185  unsigned long vlen, u32 pos_low, u32 pos_high)
1186 {
1187  loff_t pos = ((loff_t)pos_high << 32) | pos_low;
1188  return compat_sys_preadv64(fd, vec, vlen, pos);
1189 }
1190 
1191 static size_t compat_writev(struct file *file,
1192  const struct compat_iovec __user *vec,
1193  unsigned long vlen, loff_t *pos)
1194 {
1195  ssize_t ret = -EBADF;
1196 
1197  if (!(file->f_mode & FMODE_WRITE))
1198  goto out;
1199 
1200  ret = -EINVAL;
1201  if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write))
1202  goto out;
1203 
1204  ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);
1205 
1206 out:
1207  if (ret > 0)
1208  add_wchar(current, ret);
1209  inc_syscw(current);
1210  return ret;
1211 }
1212 
1213 asmlinkage ssize_t
1214 compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec,
1215  unsigned long vlen)
1216 {
1217  struct fd f = fdget(fd);
1218  ssize_t ret;
1219  loff_t pos;
1220 
1221  if (!f.file)
1222  return -EBADF;
1223  pos = f.file->f_pos;
1224  ret = compat_writev(f.file, vec, vlen, &pos);
1225  f.file->f_pos = pos;
1226  fdput(f);
1227  return ret;
1228 }
1229 
1230 asmlinkage ssize_t
1231 compat_sys_pwritev64(unsigned long fd, const struct compat_iovec __user *vec,
1232  unsigned long vlen, loff_t pos)
1233 {
1234  struct fd f;
1235  ssize_t ret;
1236 
1237  if (pos < 0)
1238  return -EINVAL;
1239  f = fdget(fd);
1240  if (!f.file)
1241  return -EBADF;
1242  ret = -ESPIPE;
1243  if (f.file->f_mode & FMODE_PWRITE)
1244  ret = compat_writev(f.file, vec, vlen, &pos);
1245  fdput(f);
1246  return ret;
1247 }
1248 
1249 asmlinkage ssize_t
1250 compat_sys_pwritev(unsigned long fd, const struct compat_iovec __user *vec,
1251  unsigned long vlen, u32 pos_low, u32 pos_high)
1252 {
1253  loff_t pos = ((loff_t)pos_high << 32) | pos_low;
1254  return compat_sys_pwritev64(fd, vec, vlen, pos);
1255 }
1256 
1257 asmlinkage long
1258 compat_sys_vmsplice(int fd, const struct compat_iovec __user *iov32,
1259  unsigned int nr_segs, unsigned int flags)
1260 {
1261  unsigned i;
1262  struct iovec __user *iov;
1263  if (nr_segs > UIO_MAXIOV)
1264  return -EINVAL;
1265  iov = compat_alloc_user_space(nr_segs * sizeof(struct iovec));
1266  for (i = 0; i < nr_segs; i++) {
1267  struct compat_iovec v;
1268  if (get_user(v.iov_base, &iov32[i].iov_base) ||
1269  get_user(v.iov_len, &iov32[i].iov_len) ||
1270  put_user(compat_ptr(v.iov_base), &iov[i].iov_base) ||
1271  put_user(v.iov_len, &iov[i].iov_len))
1272  return -EFAULT;
1273  }
1274  return sys_vmsplice(fd, iov, nr_segs, flags);
1275 }
1276 
1277 /*
1278  * Exactly like fs/open.c:sys_open(), except that it doesn't set the
1279  * O_LARGEFILE flag.
1280  */
1281 asmlinkage long
1282 compat_sys_open(const char __user *filename, int flags, umode_t mode)
1283 {
1284  return do_sys_open(AT_FDCWD, filename, flags, mode);
1285 }
1286 
1287 /*
1288  * Exactly like fs/open.c:sys_openat(), except that it doesn't set the
1289  * O_LARGEFILE flag.
1290  */
1291 asmlinkage long
1292 compat_sys_openat(unsigned int dfd, const char __user *filename, int flags, umode_t mode)
1293 {
1294  return do_sys_open(dfd, filename, flags, mode);
1295 }
1296 
1297 #define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
1298 
1299 static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
1300  int timeval, int ret)
1301 {
1302  struct timespec ts;
1303 
1304  if (!p)
1305  return ret;
1306 
1307  if (current->personality & STICKY_TIMEOUTS)
1308  goto sticky;
1309 
1310  /* No update for zero timeout */
1311  if (!end_time->tv_sec && !end_time->tv_nsec)
1312  return ret;
1313 
1314  ktime_get_ts(&ts);
1315  ts = timespec_sub(*end_time, ts);
1316  if (ts.tv_sec < 0)
1317  ts.tv_sec = ts.tv_nsec = 0;
1318 
1319  if (timeval) {
1320  struct compat_timeval rtv;
1321 
1322  rtv.tv_sec = ts.tv_sec;
1323  rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
1324 
1325  if (!copy_to_user(p, &rtv, sizeof(rtv)))
1326  return ret;
1327  } else {
1328  struct compat_timespec rts;
1329 
1330  rts.tv_sec = ts.tv_sec;
1331  rts.tv_nsec = ts.tv_nsec;
1332 
1333  if (!copy_to_user(p, &rts, sizeof(rts)))
1334  return ret;
1335  }
1336  /*
1337  * If an application puts its timeval in read-only memory, we
1338  * don't want the Linux-specific update to the timeval to
1339  * cause a fault after the select has completed
1340  * successfully. However, because we're not updating the
1341  * timeval, we can't restart the system call.
1342  */
1343 
1344 sticky:
1345  if (ret == -ERESTARTNOHAND)
1346  ret = -EINTR;
1347  return ret;
1348 }
1349 
1350 /*
1351  * Ooo, nasty. We need here to frob 32-bit unsigned longs to
1352  * 64-bit unsigned longs.
1353  */
1354 static
1355 int compat_get_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
1356  unsigned long *fdset)
1357 {
1358  nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
1359  if (ufdset) {
1360  unsigned long odd;
1361 
1362  if (!access_ok(VERIFY_WRITE, ufdset, nr*sizeof(compat_ulong_t)))
1363  return -EFAULT;
1364 
1365  odd = nr & 1UL;
1366  nr &= ~1UL;
1367  while (nr) {
1368  unsigned long h, l;
1369  if (__get_user(l, ufdset) || __get_user(h, ufdset+1))
1370  return -EFAULT;
1371  ufdset += 2;
1372  *fdset++ = h << 32 | l;
1373  nr -= 2;
1374  }
1375  if (odd && __get_user(*fdset, ufdset))
1376  return -EFAULT;
1377  } else {
1378  /* Tricky, must clear full unsigned long in the
1379  * kernel fdset at the end, this makes sure that
1380  * actually happens.
1381  */
1382  memset(fdset, 0, ((nr + 1) & ~1)*sizeof(compat_ulong_t));
1383  }
1384  return 0;
1385 }
1386 
1387 static
1388 int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
1389  unsigned long *fdset)
1390 {
1391  unsigned long odd;
1392  nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
1393 
1394  if (!ufdset)
1395  return 0;
1396 
1397  odd = nr & 1UL;
1398  nr &= ~1UL;
1399  while (nr) {
1400  unsigned long h, l;
1401  l = *fdset++;
1402  h = l >> 32;
1403  if (__put_user(l, ufdset) || __put_user(h, ufdset+1))
1404  return -EFAULT;
1405  ufdset += 2;
1406  nr -= 2;
1407  }
1408  if (odd && __put_user(*fdset, ufdset))
1409  return -EFAULT;
1410  return 0;
1411 }
1412 
1413 
1414 /*
1415  * This is a virtual copy of sys_select from fs/select.c and probably
1416  * should be compared to it from time to time
1417  */
1418 
1419 /*
1420  * We can actually return ERESTARTSYS instead of EINTR, but I'd
1421  * like to be certain this leads to no problems. So I return
1422  * EINTR just for safety.
1423  *
1424  * Update: ERESTARTSYS breaks at least the xview clock binary, so
1425  * I'm trying ERESTARTNOHAND which restart only when you want to.
1426  */
1427 int compat_core_sys_select(int n, compat_ulong_t __user *inp,
1428  compat_ulong_t __user *outp, compat_ulong_t __user *exp,
1429  struct timespec *end_time)
1430 {
1431  fd_set_bits fds;
1432  void *bits;
1433  int size, max_fds, ret = -EINVAL;
1434  struct fdtable *fdt;
1435  long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
1436 
1437  if (n < 0)
1438  goto out_nofds;
1439 
1440  /* max_fds can increase, so grab it once to avoid race */
1441  rcu_read_lock();
1442  fdt = files_fdtable(current->files);
1443  max_fds = fdt->max_fds;
1444  rcu_read_unlock();
1445  if (n > max_fds)
1446  n = max_fds;
1447 
1448  /*
1449  * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
1450  * since we used fdset we need to allocate memory in units of
1451  * long-words.
1452  */
1453  size = FDS_BYTES(n);
1454  bits = stack_fds;
1455  if (size > sizeof(stack_fds) / 6) {
1456  bits = kmalloc(6 * size, GFP_KERNEL);
1457  ret = -ENOMEM;
1458  if (!bits)
1459  goto out_nofds;
1460  }
1461  fds.in = (unsigned long *) bits;
1462  fds.out = (unsigned long *) (bits + size);
1463  fds.ex = (unsigned long *) (bits + 2*size);
1464  fds.res_in = (unsigned long *) (bits + 3*size);
1465  fds.res_out = (unsigned long *) (bits + 4*size);
1466  fds.res_ex = (unsigned long *) (bits + 5*size);
1467 
1468  if ((ret = compat_get_fd_set(n, inp, fds.in)) ||
1469  (ret = compat_get_fd_set(n, outp, fds.out)) ||
1470  (ret = compat_get_fd_set(n, exp, fds.ex)))
1471  goto out;
1472  zero_fd_set(n, fds.res_in);
1473  zero_fd_set(n, fds.res_out);
1474  zero_fd_set(n, fds.res_ex);
1475 
1476  ret = do_select(n, &fds, end_time);
1477 
1478  if (ret < 0)
1479  goto out;
1480  if (!ret) {
1481  ret = -ERESTARTNOHAND;
1482  if (signal_pending(current))
1483  goto out;
1484  ret = 0;
1485  }
1486 
1487  if (compat_set_fd_set(n, inp, fds.res_in) ||
1488  compat_set_fd_set(n, outp, fds.res_out) ||
1489  compat_set_fd_set(n, exp, fds.res_ex))
1490  ret = -EFAULT;
1491 out:
1492  if (bits != stack_fds)
1493  kfree(bits);
1494 out_nofds:
1495  return ret;
1496 }
1497 
1498 asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp,
1499  compat_ulong_t __user *outp, compat_ulong_t __user *exp,
1500  struct compat_timeval __user *tvp)
1501 {
1502  struct timespec end_time, *to = NULL;
1503  struct compat_timeval tv;
1504  int ret;
1505 
1506  if (tvp) {
1507  if (copy_from_user(&tv, tvp, sizeof(tv)))
1508  return -EFAULT;
1509 
1510  to = &end_time;
1511  if (poll_select_set_timeout(to,
1512  tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
1513  (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
1514  return -EINVAL;
1515  }
1516 
1517  ret = compat_core_sys_select(n, inp, outp, exp, to);
1518  ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);
1519 
1520  return ret;
1521 }
1522 
1523 struct compat_sel_arg_struct {
1524  compat_ulong_t n;
1525  compat_uptr_t inp;
1526  compat_uptr_t outp;
1527  compat_uptr_t exp;
1528  compat_uptr_t tvp;
1529 };
1530 
1531 asmlinkage long compat_sys_old_select(struct compat_sel_arg_struct __user *arg)
1532 {
1533  struct compat_sel_arg_struct a;
1534 
1535  if (copy_from_user(&a, arg, sizeof(a)))
1536  return -EFAULT;
1537  return compat_sys_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp),
1538  compat_ptr(a.exp), compat_ptr(a.tvp));
1539 }
1540 
1541 static long do_compat_pselect(int n, compat_ulong_t __user *inp,
1542  compat_ulong_t __user *outp, compat_ulong_t __user *exp,
1543  struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask,
1544  compat_size_t sigsetsize)
1545 {
1546  compat_sigset_t ss32;
1547  sigset_t ksigmask, sigsaved;
1548  struct compat_timespec ts;
1549  struct timespec end_time, *to = NULL;
1550  int ret;
1551 
1552  if (tsp) {
1553  if (copy_from_user(&ts, tsp, sizeof(ts)))
1554  return -EFAULT;
1555 
1556  to = &end_time;
1557  if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
1558  return -EINVAL;
1559  }
1560 
1561  if (sigmask) {
1562  if (sigsetsize != sizeof(compat_sigset_t))
1563  return -EINVAL;
1564  if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
1565  return -EFAULT;
1566  sigset_from_compat(&ksigmask, &ss32);
1567 
1568  sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
1569  sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
1570  }
1571 
1572  ret = compat_core_sys_select(n, inp, outp, exp, to);
1573  ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
1574 
1575  if (ret == -ERESTARTNOHAND) {
1576  /*
1577  * Don't restore the signal mask yet. Let do_signal() deliver
1578  * the signal on the way back to userspace, before the signal
1579  * mask is restored.
1580  */
1581  if (sigmask) {
1582  memcpy(&current->saved_sigmask, &sigsaved,
1583  sizeof(sigsaved));
1584  set_restore_sigmask();
1585  }
1586  } else if (sigmask)
1587  sigprocmask(SIG_SETMASK, &sigsaved, NULL);
1588 
1589  return ret;
1590 }
1591 
1592 asmlinkage long compat_sys_pselect6(int n, compat_ulong_t __user *inp,
1593  compat_ulong_t __user *outp, compat_ulong_t __user *exp,
1594  struct compat_timespec __user *tsp, void __user *sig)
1595 {
1596  compat_size_t sigsetsize = 0;
1597  compat_uptr_t up = 0;
1598 
1599  if (sig) {
1600  if (!access_ok(VERIFY_READ, sig,
1601  sizeof(compat_uptr_t)+sizeof(compat_size_t)) ||
1602  __get_user(up, (compat_uptr_t __user *)sig) ||
1603  __get_user(sigsetsize,
1604  (compat_size_t __user *)(sig+sizeof(up))))
1605  return -EFAULT;
1606  }
1607  return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(up),
1608  sigsetsize);
1609 }
1610 
1611 asmlinkage long compat_sys_ppoll(struct pollfd __user *ufds,
1612  unsigned int nfds, struct compat_timespec __user *tsp,
1613  const compat_sigset_t __user *sigmask, compat_size_t sigsetsize)
1614 {
1615  compat_sigset_t ss32;
1616  sigset_t ksigmask, sigsaved;
1617  struct compat_timespec ts;
1618  struct timespec end_time, *to = NULL;
1619  int ret;
1620 
1621  if (tsp) {
1622  if (copy_from_user(&ts, tsp, sizeof(ts)))
1623  return -EFAULT;
1624 
1625  to = &end_time;
1626  if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
1627  return -EINVAL;
1628  }
1629 
1630  if (sigmask) {
1631  if (sigsetsize != sizeof(compat_sigset_t))
1632  return -EINVAL;
1633  if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
1634  return -EFAULT;
1635  sigset_from_compat(&ksigmask, &ss32);
1636 
1637  sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
1638  sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
1639  }
1640 
1641  ret = do_sys_poll(ufds, nfds, to);
1642 
1643  /* We can restart this syscall, usually */
1644  if (ret == -EINTR) {
1645  /*
1646  * Don't restore the signal mask yet. Let do_signal() deliver
1647  * the signal on the way back to userspace, before the signal
1648  * mask is restored.
1649  */
1650  if (sigmask) {
1651  memcpy(&current->saved_sigmask, &sigsaved,
1652  sizeof(sigsaved));
1653  set_restore_sigmask();
1654  }
1655  ret = -ERESTARTNOHAND;
1656  } else if (sigmask)
1657  sigprocmask(SIG_SETMASK, &sigsaved, NULL);
1658 
1659  ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
1660 
1661  return ret;
1662 }
1663 
1664 #ifdef CONFIG_EPOLL
1665 
1666 asmlinkage long compat_sys_epoll_pwait(int epfd,
1667  struct compat_epoll_event __user *events,
1668  int maxevents, int timeout,
1669  const compat_sigset_t __user *sigmask,
1670  compat_size_t sigsetsize)
1671 {
1672  long err;
1673  compat_sigset_t csigmask;
1674  sigset_t ksigmask, sigsaved;
1675 
1676  /*
1677  * If the caller wants a certain signal mask to be set during the wait,
1678  * we apply it here.
1679  */
1680  if (sigmask) {
1681  if (sigsetsize != sizeof(compat_sigset_t))
1682  return -EINVAL;
1683  if (copy_from_user(&csigmask, sigmask, sizeof(csigmask)))
1684  return -EFAULT;
1685  sigset_from_compat(&ksigmask, &csigmask);
1686  sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
1687  sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
1688  }
1689 
1690  err = sys_epoll_wait(epfd, events, maxevents, timeout);
1691 
1692  /*
1693  * If we changed the signal mask, we need to restore the original one.
1694  * In case we've got a signal while waiting, we do not restore the
1695  * signal mask yet, and we allow do_signal() to deliver the signal on
1696  * the way back to userspace, before the signal mask is restored.
1697  */
1698  if (sigmask) {
1699  if (err == -EINTR) {
1700  memcpy(&current->saved_sigmask, &sigsaved,
1701  sizeof(sigsaved));
1702  set_restore_sigmask();
1703  } else
1704  sigprocmask(SIG_SETMASK, &sigsaved, NULL);
1705  }
1706 
1707  return err;
1708 }
1709 
1710 #endif /* CONFIG_EPOLL */
1711 
1712 #ifdef CONFIG_SIGNALFD
1713 
1714 asmlinkage long compat_sys_signalfd4(int ufd,
1715  const compat_sigset_t __user *sigmask,
1716  compat_size_t sigsetsize, int flags)
1717 {
1718  compat_sigset_t ss32;
1719  sigset_t tmp;
1720  sigset_t __user *ksigmask;
1721 
1722  if (sigsetsize != sizeof(compat_sigset_t))
1723  return -EINVAL;
1724  if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
1725  return -EFAULT;
1726  sigset_from_compat(&tmp, &ss32);
1727  ksigmask = compat_alloc_user_space(sizeof(sigset_t));
1728  if (copy_to_user(ksigmask, &tmp, sizeof(sigset_t)))
1729  return -EFAULT;
1730 
1731  return sys_signalfd4(ufd, ksigmask, sizeof(sigset_t), flags);
1732 }
1733 
1734 asmlinkage long compat_sys_signalfd(int ufd,
1735  const compat_sigset_t __user *sigmask,
1736  compat_size_t sigsetsize)
1737 {
1738  return compat_sys_signalfd4(ufd, sigmask, sigsetsize, 0);
1739 }
1740 #endif /* CONFIG_SIGNALFD */
1741 
1742 #ifdef CONFIG_TIMERFD
1743 
1744 asmlinkage long compat_sys_timerfd_settime(int ufd, int flags,
1745  const struct compat_itimerspec __user *utmr,
1746  struct compat_itimerspec __user *otmr)
1747 {
1748  int error;
1749  struct itimerspec t;
1750  struct itimerspec __user *ut;
1751 
1752  if (get_compat_itimerspec(&t, utmr))
1753  return -EFAULT;
1754  ut = compat_alloc_user_space(2 * sizeof(struct itimerspec));
1755  if (copy_to_user(&ut[0], &t, sizeof(t)))
1756  return -EFAULT;
1757  error = sys_timerfd_settime(ufd, flags, &ut[0], &ut[1]);
1758  if (!error && otmr)
1759  error = (copy_from_user(&t, &ut[1], sizeof(struct itimerspec)) ||
1760  put_compat_itimerspec(otmr, &t)) ? -EFAULT: 0;
1761 
1762  return error;
1763 }
1764 
1765 asmlinkage long compat_sys_timerfd_gettime(int ufd,
1766  struct compat_itimerspec __user *otmr)
1767 {
1768  int error;
1769  struct itimerspec t;
1770  struct itimerspec __user *ut;
1771 
1772  ut = compat_alloc_user_space(sizeof(struct itimerspec));
1773  error = sys_timerfd_gettime(ufd, ut);
1774  if (!error)
1775  error = (copy_from_user(&t, ut, sizeof(struct itimerspec)) ||
1776  put_compat_itimerspec(otmr, &t)) ? -EFAULT: 0;
1777 
1778  return error;
1779 }
1780 
1781 #endif /* CONFIG_TIMERFD */
1782 
1783 #ifdef CONFIG_FHANDLE
1784 /*
1785  * Exactly like fs/open.c:sys_open_by_handle_at(), except that it
1786  * doesn't set the O_LARGEFILE flag.
1787  */
1788 asmlinkage long
1789 compat_sys_open_by_handle_at(int mountdirfd,
1790  struct file_handle __user *handle, int flags)
1791 {
1792  return do_handle_open(mountdirfd, handle, flags);
1793 }
1794 #endif
1795 
1796 #ifdef __ARCH_WANT_COMPAT_SYS_SENDFILE
1797 asmlinkage long compat_sys_sendfile(int out_fd, int in_fd,
1798  compat_off_t __user *offset, compat_size_t count)
1799 {
1800  loff_t pos;
1801  off_t off;
1802  ssize_t ret;
1803 
1804  if (offset) {
1805  if (unlikely(get_user(off, offset)))
1806  return -EFAULT;
1807  pos = off;
1808  ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1809  if (unlikely(put_user(pos, offset)))
1810  return -EFAULT;
1811  return ret;
1812  }
1813 
1814  return do_sendfile(out_fd, in_fd, NULL, count, 0);
1815 }
1816 #endif /* __ARCH_WANT_COMPAT_SYS_SENDFILE */
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