1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/ioctl.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
8#include <linux/syscalls.h>
9#include <linux/mm.h>
10#include <linux/capability.h>
11#include <linux/compat.h>
12#include <linux/file.h>
13#include <linux/fs.h>
14#include <linux/security.h>
15#include <linux/export.h>
16#include <linux/uaccess.h>
17#include <linux/writeback.h>
18#include <linux/buffer_head.h>
19#include <linux/falloc.h>
20#include <linux/sched/signal.h>
21#include <linux/fiemap.h>
22#include <linux/mount.h>
23#include <linux/fscrypt.h>
24#include <linux/fileattr.h>
25
26#include "internal.h"
27
28#include <asm/ioctls.h>
29
30/* So that the fiemap access checks can't overflow on 32 bit machines. */
31#define FIEMAP_MAX_EXTENTS (UINT_MAX / sizeof(struct fiemap_extent))
32
33/**
34 * vfs_ioctl - call filesystem specific ioctl methods
35 * @filp: open file to invoke ioctl method on
36 * @cmd: ioctl command to execute
37 * @arg: command-specific argument for ioctl
38 *
39 * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
40 * returns -ENOTTY.
41 *
42 * Returns 0 on success, -errno on error.
43 */
44long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
45{
46 int error = -ENOTTY;
47
48 if (!filp->f_op->unlocked_ioctl)
49 goto out;
50
51 error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
52 if (error == -ENOIOCTLCMD)
53 error = -ENOTTY;
54 out:
55 return error;
56}
57EXPORT_SYMBOL(vfs_ioctl);
58
59static int ioctl_fibmap(struct file *filp, int __user *p)
60{
61 struct inode *inode = file_inode(f: filp);
62 struct super_block *sb = inode->i_sb;
63 int error, ur_block;
64 sector_t block;
65
66 if (!capable(CAP_SYS_RAWIO))
67 return -EPERM;
68
69 error = get_user(ur_block, p);
70 if (error)
71 return error;
72
73 if (ur_block < 0)
74 return -EINVAL;
75
76 block = ur_block;
77 error = bmap(inode, block: &block);
78
79 if (block > INT_MAX) {
80 error = -ERANGE;
81 pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result\n",
82 current->comm, task_pid_nr(current),
83 sb->s_id, filp);
84 }
85
86 if (error)
87 ur_block = 0;
88 else
89 ur_block = block;
90
91 if (put_user(ur_block, p))
92 error = -EFAULT;
93
94 return error;
95}
96
97/**
98 * fiemap_fill_next_extent - Fiemap helper function
99 * @fieinfo: Fiemap context passed into ->fiemap
100 * @logical: Extent logical start offset, in bytes
101 * @phys: Extent physical start offset, in bytes
102 * @len: Extent length, in bytes
103 * @flags: FIEMAP_EXTENT flags that describe this extent
104 *
105 * Called from file system ->fiemap callback. Will populate extent
106 * info as passed in via arguments and copy to user memory. On
107 * success, extent count on fieinfo is incremented.
108 *
109 * Returns 0 on success, -errno on error, 1 if this was the last
110 * extent that will fit in user array.
111 */
112int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
113 u64 phys, u64 len, u32 flags)
114{
115 struct fiemap_extent extent;
116 struct fiemap_extent __user *dest = fieinfo->fi_extents_start;
117
118 /* only count the extents */
119 if (fieinfo->fi_extents_max == 0) {
120 fieinfo->fi_extents_mapped++;
121 return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
122 }
123
124 if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
125 return 1;
126
127#define SET_UNKNOWN_FLAGS (FIEMAP_EXTENT_DELALLOC)
128#define SET_NO_UNMOUNTED_IO_FLAGS (FIEMAP_EXTENT_DATA_ENCRYPTED)
129#define SET_NOT_ALIGNED_FLAGS (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
130
131 if (flags & SET_UNKNOWN_FLAGS)
132 flags |= FIEMAP_EXTENT_UNKNOWN;
133 if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
134 flags |= FIEMAP_EXTENT_ENCODED;
135 if (flags & SET_NOT_ALIGNED_FLAGS)
136 flags |= FIEMAP_EXTENT_NOT_ALIGNED;
137
138 memset(&extent, 0, sizeof(extent));
139 extent.fe_logical = logical;
140 extent.fe_physical = phys;
141 extent.fe_length = len;
142 extent.fe_flags = flags;
143
144 dest += fieinfo->fi_extents_mapped;
145 if (copy_to_user(to: dest, from: &extent, n: sizeof(extent)))
146 return -EFAULT;
147
148 fieinfo->fi_extents_mapped++;
149 if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
150 return 1;
151 return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
152}
153EXPORT_SYMBOL(fiemap_fill_next_extent);
154
155/**
156 * fiemap_prep - check validity of requested flags for fiemap
157 * @inode: Inode to operate on
158 * @fieinfo: Fiemap context passed into ->fiemap
159 * @start: Start of the mapped range
160 * @len: Length of the mapped range, can be truncated by this function.
161 * @supported_flags: Set of fiemap flags that the file system understands
162 *
163 * This function must be called from each ->fiemap instance to validate the
164 * fiemap request against the file system parameters.
165 *
166 * Returns 0 on success, or a negative error on failure.
167 */
168int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo,
169 u64 start, u64 *len, u32 supported_flags)
170{
171 u64 maxbytes = inode->i_sb->s_maxbytes;
172 u32 incompat_flags;
173 int ret = 0;
174
175 if (*len == 0)
176 return -EINVAL;
177 if (start >= maxbytes)
178 return -EFBIG;
179
180 /*
181 * Shrink request scope to what the fs can actually handle.
182 */
183 if (*len > maxbytes || (maxbytes - *len) < start)
184 *len = maxbytes - start;
185
186 supported_flags |= FIEMAP_FLAG_SYNC;
187 supported_flags &= FIEMAP_FLAGS_COMPAT;
188 incompat_flags = fieinfo->fi_flags & ~supported_flags;
189 if (incompat_flags) {
190 fieinfo->fi_flags = incompat_flags;
191 return -EBADR;
192 }
193
194 if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
195 ret = filemap_write_and_wait(mapping: inode->i_mapping);
196 return ret;
197}
198EXPORT_SYMBOL(fiemap_prep);
199
200static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap)
201{
202 struct fiemap fiemap;
203 struct fiemap_extent_info fieinfo = { 0, };
204 struct inode *inode = file_inode(f: filp);
205 int error;
206
207 if (!inode->i_op->fiemap)
208 return -EOPNOTSUPP;
209
210 if (copy_from_user(to: &fiemap, from: ufiemap, n: sizeof(fiemap)))
211 return -EFAULT;
212
213 if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
214 return -EINVAL;
215
216 fieinfo.fi_flags = fiemap.fm_flags;
217 fieinfo.fi_extents_max = fiemap.fm_extent_count;
218 fieinfo.fi_extents_start = ufiemap->fm_extents;
219
220 error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start,
221 fiemap.fm_length);
222
223 fiemap.fm_flags = fieinfo.fi_flags;
224 fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
225 if (copy_to_user(to: ufiemap, from: &fiemap, n: sizeof(fiemap)))
226 error = -EFAULT;
227
228 return error;
229}
230
231static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
232 u64 off, u64 olen, u64 destoff)
233{
234 struct fd src_file = fdget(fd: srcfd);
235 loff_t cloned;
236 int ret;
237
238 if (!src_file.file)
239 return -EBADF;
240 cloned = vfs_clone_file_range(file_in: src_file.file, pos_in: off, file_out: dst_file, pos_out: destoff,
241 len: olen, remap_flags: 0);
242 if (cloned < 0)
243 ret = cloned;
244 else if (olen && cloned != olen)
245 ret = -EINVAL;
246 else
247 ret = 0;
248 fdput(fd: src_file);
249 return ret;
250}
251
252static long ioctl_file_clone_range(struct file *file,
253 struct file_clone_range __user *argp)
254{
255 struct file_clone_range args;
256
257 if (copy_from_user(to: &args, from: argp, n: sizeof(args)))
258 return -EFAULT;
259 return ioctl_file_clone(dst_file: file, srcfd: args.src_fd, off: args.src_offset,
260 olen: args.src_length, destoff: args.dest_offset);
261}
262
263/*
264 * This provides compatibility with legacy XFS pre-allocation ioctls
265 * which predate the fallocate syscall.
266 *
267 * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
268 * are used here, rest are ignored.
269 */
270static int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
271{
272 struct inode *inode = file_inode(f: filp);
273 struct space_resv sr;
274
275 if (copy_from_user(to: &sr, from: argp, n: sizeof(sr)))
276 return -EFAULT;
277
278 switch (sr.l_whence) {
279 case SEEK_SET:
280 break;
281 case SEEK_CUR:
282 sr.l_start += filp->f_pos;
283 break;
284 case SEEK_END:
285 sr.l_start += i_size_read(inode);
286 break;
287 default:
288 return -EINVAL;
289 }
290
291 return vfs_fallocate(file: filp, mode: mode | FALLOC_FL_KEEP_SIZE, offset: sr.l_start,
292 len: sr.l_len);
293}
294
295/* on ia32 l_start is on a 32-bit boundary */
296#if defined CONFIG_COMPAT && defined(CONFIG_X86_64)
297/* just account for different alignment */
298static int compat_ioctl_preallocate(struct file *file, int mode,
299 struct space_resv_32 __user *argp)
300{
301 struct inode *inode = file_inode(f: file);
302 struct space_resv_32 sr;
303
304 if (copy_from_user(to: &sr, from: argp, n: sizeof(sr)))
305 return -EFAULT;
306
307 switch (sr.l_whence) {
308 case SEEK_SET:
309 break;
310 case SEEK_CUR:
311 sr.l_start += file->f_pos;
312 break;
313 case SEEK_END:
314 sr.l_start += i_size_read(inode);
315 break;
316 default:
317 return -EINVAL;
318 }
319
320 return vfs_fallocate(file, mode: mode | FALLOC_FL_KEEP_SIZE, offset: sr.l_start, len: sr.l_len);
321}
322#endif
323
324static int file_ioctl(struct file *filp, unsigned int cmd, int __user *p)
325{
326 switch (cmd) {
327 case FIBMAP:
328 return ioctl_fibmap(filp, p);
329 case FS_IOC_RESVSP:
330 case FS_IOC_RESVSP64:
331 return ioctl_preallocate(filp, mode: 0, argp: p);
332 case FS_IOC_UNRESVSP:
333 case FS_IOC_UNRESVSP64:
334 return ioctl_preallocate(filp, FALLOC_FL_PUNCH_HOLE, argp: p);
335 case FS_IOC_ZERO_RANGE:
336 return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, argp: p);
337 }
338
339 return -ENOIOCTLCMD;
340}
341
342static int ioctl_fionbio(struct file *filp, int __user *argp)
343{
344 unsigned int flag;
345 int on, error;
346
347 error = get_user(on, argp);
348 if (error)
349 return error;
350 flag = O_NONBLOCK;
351#ifdef __sparc__
352 /* SunOS compatibility item. */
353 if (O_NONBLOCK != O_NDELAY)
354 flag |= O_NDELAY;
355#endif
356 spin_lock(lock: &filp->f_lock);
357 if (on)
358 filp->f_flags |= flag;
359 else
360 filp->f_flags &= ~flag;
361 spin_unlock(lock: &filp->f_lock);
362 return error;
363}
364
365static int ioctl_fioasync(unsigned int fd, struct file *filp,
366 int __user *argp)
367{
368 unsigned int flag;
369 int on, error;
370
371 error = get_user(on, argp);
372 if (error)
373 return error;
374 flag = on ? FASYNC : 0;
375
376 /* Did FASYNC state change ? */
377 if ((flag ^ filp->f_flags) & FASYNC) {
378 if (filp->f_op->fasync)
379 /* fasync() adjusts filp->f_flags */
380 error = filp->f_op->fasync(fd, filp, on);
381 else
382 error = -ENOTTY;
383 }
384 return error < 0 ? error : 0;
385}
386
387static int ioctl_fsfreeze(struct file *filp)
388{
389 struct super_block *sb = file_inode(f: filp)->i_sb;
390
391 if (!ns_capable(ns: sb->s_user_ns, CAP_SYS_ADMIN))
392 return -EPERM;
393
394 /* If filesystem doesn't support freeze feature, return. */
395 if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
396 return -EOPNOTSUPP;
397
398 /* Freeze */
399 if (sb->s_op->freeze_super)
400 return sb->s_op->freeze_super(sb, FREEZE_HOLDER_USERSPACE);
401 return freeze_super(super: sb, who: FREEZE_HOLDER_USERSPACE);
402}
403
404static int ioctl_fsthaw(struct file *filp)
405{
406 struct super_block *sb = file_inode(f: filp)->i_sb;
407
408 if (!ns_capable(ns: sb->s_user_ns, CAP_SYS_ADMIN))
409 return -EPERM;
410
411 /* Thaw */
412 if (sb->s_op->thaw_super)
413 return sb->s_op->thaw_super(sb, FREEZE_HOLDER_USERSPACE);
414 return thaw_super(super: sb, who: FREEZE_HOLDER_USERSPACE);
415}
416
417static int ioctl_file_dedupe_range(struct file *file,
418 struct file_dedupe_range __user *argp)
419{
420 struct file_dedupe_range *same = NULL;
421 int ret;
422 unsigned long size;
423 u16 count;
424
425 if (get_user(count, &argp->dest_count)) {
426 ret = -EFAULT;
427 goto out;
428 }
429
430 size = offsetof(struct file_dedupe_range, info[count]);
431 if (size > PAGE_SIZE) {
432 ret = -ENOMEM;
433 goto out;
434 }
435
436 same = memdup_user(argp, size);
437 if (IS_ERR(ptr: same)) {
438 ret = PTR_ERR(ptr: same);
439 same = NULL;
440 goto out;
441 }
442
443 same->dest_count = count;
444 ret = vfs_dedupe_file_range(file, same);
445 if (ret)
446 goto out;
447
448 ret = copy_to_user(to: argp, from: same, n: size);
449 if (ret)
450 ret = -EFAULT;
451
452out:
453 kfree(objp: same);
454 return ret;
455}
456
457/**
458 * fileattr_fill_xflags - initialize fileattr with xflags
459 * @fa: fileattr pointer
460 * @xflags: FS_XFLAG_* flags
461 *
462 * Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags). All
463 * other fields are zeroed.
464 */
465void fileattr_fill_xflags(struct fileattr *fa, u32 xflags)
466{
467 memset(fa, 0, sizeof(*fa));
468 fa->fsx_valid = true;
469 fa->fsx_xflags = xflags;
470 if (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)
471 fa->flags |= FS_IMMUTABLE_FL;
472 if (fa->fsx_xflags & FS_XFLAG_APPEND)
473 fa->flags |= FS_APPEND_FL;
474 if (fa->fsx_xflags & FS_XFLAG_SYNC)
475 fa->flags |= FS_SYNC_FL;
476 if (fa->fsx_xflags & FS_XFLAG_NOATIME)
477 fa->flags |= FS_NOATIME_FL;
478 if (fa->fsx_xflags & FS_XFLAG_NODUMP)
479 fa->flags |= FS_NODUMP_FL;
480 if (fa->fsx_xflags & FS_XFLAG_DAX)
481 fa->flags |= FS_DAX_FL;
482 if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
483 fa->flags |= FS_PROJINHERIT_FL;
484}
485EXPORT_SYMBOL(fileattr_fill_xflags);
486
487/**
488 * fileattr_fill_flags - initialize fileattr with flags
489 * @fa: fileattr pointer
490 * @flags: FS_*_FL flags
491 *
492 * Set ->flags, ->flags_valid and ->fsx_xflags (translated flags).
493 * All other fields are zeroed.
494 */
495void fileattr_fill_flags(struct fileattr *fa, u32 flags)
496{
497 memset(fa, 0, sizeof(*fa));
498 fa->flags_valid = true;
499 fa->flags = flags;
500 if (fa->flags & FS_SYNC_FL)
501 fa->fsx_xflags |= FS_XFLAG_SYNC;
502 if (fa->flags & FS_IMMUTABLE_FL)
503 fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
504 if (fa->flags & FS_APPEND_FL)
505 fa->fsx_xflags |= FS_XFLAG_APPEND;
506 if (fa->flags & FS_NODUMP_FL)
507 fa->fsx_xflags |= FS_XFLAG_NODUMP;
508 if (fa->flags & FS_NOATIME_FL)
509 fa->fsx_xflags |= FS_XFLAG_NOATIME;
510 if (fa->flags & FS_DAX_FL)
511 fa->fsx_xflags |= FS_XFLAG_DAX;
512 if (fa->flags & FS_PROJINHERIT_FL)
513 fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
514}
515EXPORT_SYMBOL(fileattr_fill_flags);
516
517/**
518 * vfs_fileattr_get - retrieve miscellaneous file attributes
519 * @dentry: the object to retrieve from
520 * @fa: fileattr pointer
521 *
522 * Call i_op->fileattr_get() callback, if exists.
523 *
524 * Return: 0 on success, or a negative error on failure.
525 */
526int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
527{
528 struct inode *inode = d_inode(dentry);
529
530 if (!inode->i_op->fileattr_get)
531 return -ENOIOCTLCMD;
532
533 return inode->i_op->fileattr_get(dentry, fa);
534}
535EXPORT_SYMBOL(vfs_fileattr_get);
536
537/**
538 * copy_fsxattr_to_user - copy fsxattr to userspace.
539 * @fa: fileattr pointer
540 * @ufa: fsxattr user pointer
541 *
542 * Return: 0 on success, or -EFAULT on failure.
543 */
544int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa)
545{
546 struct fsxattr xfa;
547
548 memset(&xfa, 0, sizeof(xfa));
549 xfa.fsx_xflags = fa->fsx_xflags;
550 xfa.fsx_extsize = fa->fsx_extsize;
551 xfa.fsx_nextents = fa->fsx_nextents;
552 xfa.fsx_projid = fa->fsx_projid;
553 xfa.fsx_cowextsize = fa->fsx_cowextsize;
554
555 if (copy_to_user(to: ufa, from: &xfa, n: sizeof(xfa)))
556 return -EFAULT;
557
558 return 0;
559}
560EXPORT_SYMBOL(copy_fsxattr_to_user);
561
562static int copy_fsxattr_from_user(struct fileattr *fa,
563 struct fsxattr __user *ufa)
564{
565 struct fsxattr xfa;
566
567 if (copy_from_user(to: &xfa, from: ufa, n: sizeof(xfa)))
568 return -EFAULT;
569
570 fileattr_fill_xflags(fa, xfa.fsx_xflags);
571 fa->fsx_extsize = xfa.fsx_extsize;
572 fa->fsx_nextents = xfa.fsx_nextents;
573 fa->fsx_projid = xfa.fsx_projid;
574 fa->fsx_cowextsize = xfa.fsx_cowextsize;
575
576 return 0;
577}
578
579/*
580 * Generic function to check FS_IOC_FSSETXATTR/FS_IOC_SETFLAGS values and reject
581 * any invalid configurations.
582 *
583 * Note: must be called with inode lock held.
584 */
585static int fileattr_set_prepare(struct inode *inode,
586 const struct fileattr *old_ma,
587 struct fileattr *fa)
588{
589 int err;
590
591 /*
592 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
593 * the relevant capability.
594 */
595 if ((fa->flags ^ old_ma->flags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) &&
596 !capable(CAP_LINUX_IMMUTABLE))
597 return -EPERM;
598
599 err = fscrypt_prepare_setflags(inode, oldflags: old_ma->flags, flags: fa->flags);
600 if (err)
601 return err;
602
603 /*
604 * Project Quota ID state is only allowed to change from within the init
605 * namespace. Enforce that restriction only if we are trying to change
606 * the quota ID state. Everything else is allowed in user namespaces.
607 */
608 if (current_user_ns() != &init_user_ns) {
609 if (old_ma->fsx_projid != fa->fsx_projid)
610 return -EINVAL;
611 if ((old_ma->fsx_xflags ^ fa->fsx_xflags) &
612 FS_XFLAG_PROJINHERIT)
613 return -EINVAL;
614 } else {
615 /*
616 * Caller is allowed to change the project ID. If it is being
617 * changed, make sure that the new value is valid.
618 */
619 if (old_ma->fsx_projid != fa->fsx_projid &&
620 !projid_valid(projid: make_kprojid(from: &init_user_ns, projid: fa->fsx_projid)))
621 return -EINVAL;
622 }
623
624 /* Check extent size hints. */
625 if ((fa->fsx_xflags & FS_XFLAG_EXTSIZE) && !S_ISREG(inode->i_mode))
626 return -EINVAL;
627
628 if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) &&
629 !S_ISDIR(inode->i_mode))
630 return -EINVAL;
631
632 if ((fa->fsx_xflags & FS_XFLAG_COWEXTSIZE) &&
633 !S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
634 return -EINVAL;
635
636 /*
637 * It is only valid to set the DAX flag on regular files and
638 * directories on filesystems.
639 */
640 if ((fa->fsx_xflags & FS_XFLAG_DAX) &&
641 !(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
642 return -EINVAL;
643
644 /* Extent size hints of zero turn off the flags. */
645 if (fa->fsx_extsize == 0)
646 fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);
647 if (fa->fsx_cowextsize == 0)
648 fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
649
650 return 0;
651}
652
653/**
654 * vfs_fileattr_set - change miscellaneous file attributes
655 * @idmap: idmap of the mount
656 * @dentry: the object to change
657 * @fa: fileattr pointer
658 *
659 * After verifying permissions, call i_op->fileattr_set() callback, if
660 * exists.
661 *
662 * Verifying attributes involves retrieving current attributes with
663 * i_op->fileattr_get(), this also allows initializing attributes that have
664 * not been set by the caller to current values. Inode lock is held
665 * thoughout to prevent racing with another instance.
666 *
667 * Return: 0 on success, or a negative error on failure.
668 */
669int vfs_fileattr_set(struct mnt_idmap *idmap, struct dentry *dentry,
670 struct fileattr *fa)
671{
672 struct inode *inode = d_inode(dentry);
673 struct fileattr old_ma = {};
674 int err;
675
676 if (!inode->i_op->fileattr_set)
677 return -ENOIOCTLCMD;
678
679 if (!inode_owner_or_capable(idmap, inode))
680 return -EPERM;
681
682 inode_lock(inode);
683 err = vfs_fileattr_get(dentry, &old_ma);
684 if (!err) {
685 /* initialize missing bits from old_ma */
686 if (fa->flags_valid) {
687 fa->fsx_xflags |= old_ma.fsx_xflags & ~FS_XFLAG_COMMON;
688 fa->fsx_extsize = old_ma.fsx_extsize;
689 fa->fsx_nextents = old_ma.fsx_nextents;
690 fa->fsx_projid = old_ma.fsx_projid;
691 fa->fsx_cowextsize = old_ma.fsx_cowextsize;
692 } else {
693 fa->flags |= old_ma.flags & ~FS_COMMON_FL;
694 }
695 err = fileattr_set_prepare(inode, old_ma: &old_ma, fa);
696 if (!err)
697 err = inode->i_op->fileattr_set(idmap, dentry, fa);
698 }
699 inode_unlock(inode);
700
701 return err;
702}
703EXPORT_SYMBOL(vfs_fileattr_set);
704
705static int ioctl_getflags(struct file *file, unsigned int __user *argp)
706{
707 struct fileattr fa = { .flags_valid = true }; /* hint only */
708 int err;
709
710 err = vfs_fileattr_get(file->f_path.dentry, &fa);
711 if (!err)
712 err = put_user(fa.flags, argp);
713 return err;
714}
715
716static int ioctl_setflags(struct file *file, unsigned int __user *argp)
717{
718 struct mnt_idmap *idmap = file_mnt_idmap(file);
719 struct dentry *dentry = file->f_path.dentry;
720 struct fileattr fa;
721 unsigned int flags;
722 int err;
723
724 err = get_user(flags, argp);
725 if (!err) {
726 err = mnt_want_write_file(file);
727 if (!err) {
728 fileattr_fill_flags(&fa, flags);
729 err = vfs_fileattr_set(idmap, dentry, &fa);
730 mnt_drop_write_file(file);
731 }
732 }
733 return err;
734}
735
736static int ioctl_fsgetxattr(struct file *file, void __user *argp)
737{
738 struct fileattr fa = { .fsx_valid = true }; /* hint only */
739 int err;
740
741 err = vfs_fileattr_get(file->f_path.dentry, &fa);
742 if (!err)
743 err = copy_fsxattr_to_user(&fa, argp);
744
745 return err;
746}
747
748static int ioctl_fssetxattr(struct file *file, void __user *argp)
749{
750 struct mnt_idmap *idmap = file_mnt_idmap(file);
751 struct dentry *dentry = file->f_path.dentry;
752 struct fileattr fa;
753 int err;
754
755 err = copy_fsxattr_from_user(fa: &fa, ufa: argp);
756 if (!err) {
757 err = mnt_want_write_file(file);
758 if (!err) {
759 err = vfs_fileattr_set(idmap, dentry, &fa);
760 mnt_drop_write_file(file);
761 }
762 }
763 return err;
764}
765
766static int ioctl_getfsuuid(struct file *file, void __user *argp)
767{
768 struct super_block *sb = file_inode(f: file)->i_sb;
769 struct fsuuid2 u = { .len = sb->s_uuid_len, };
770
771 if (!sb->s_uuid_len)
772 return -ENOIOCTLCMD;
773
774 memcpy(&u.uuid[0], &sb->s_uuid, sb->s_uuid_len);
775
776 return copy_to_user(to: argp, from: &u, n: sizeof(u)) ? -EFAULT : 0;
777}
778
779static int ioctl_get_fs_sysfs_path(struct file *file, void __user *argp)
780{
781 struct super_block *sb = file_inode(f: file)->i_sb;
782
783 if (!strlen(sb->s_sysfs_name))
784 return -ENOIOCTLCMD;
785
786 struct fs_sysfs_path u = {};
787
788 u.len = scnprintf(buf: u.name, size: sizeof(u.name), fmt: "%s/%s", sb->s_type->name, sb->s_sysfs_name);
789
790 return copy_to_user(to: argp, from: &u, n: sizeof(u)) ? -EFAULT : 0;
791}
792
793/*
794 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
795 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
796 *
797 * When you add any new common ioctls to the switches above and below,
798 * please ensure they have compatible arguments in compat mode.
799 */
800static int do_vfs_ioctl(struct file *filp, unsigned int fd,
801 unsigned int cmd, unsigned long arg)
802{
803 void __user *argp = (void __user *)arg;
804 struct inode *inode = file_inode(f: filp);
805
806 switch (cmd) {
807 case FIOCLEX:
808 set_close_on_exec(fd, flag: 1);
809 return 0;
810
811 case FIONCLEX:
812 set_close_on_exec(fd, flag: 0);
813 return 0;
814
815 case FIONBIO:
816 return ioctl_fionbio(filp, argp);
817
818 case FIOASYNC:
819 return ioctl_fioasync(fd, filp, argp);
820
821 case FIOQSIZE:
822 if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
823 S_ISLNK(inode->i_mode)) {
824 loff_t res = inode_get_bytes(inode);
825 return copy_to_user(to: argp, from: &res, n: sizeof(res)) ?
826 -EFAULT : 0;
827 }
828
829 return -ENOTTY;
830
831 case FIFREEZE:
832 return ioctl_fsfreeze(filp);
833
834 case FITHAW:
835 return ioctl_fsthaw(filp);
836
837 case FS_IOC_FIEMAP:
838 return ioctl_fiemap(filp, ufiemap: argp);
839
840 case FIGETBSZ:
841 /* anon_bdev filesystems may not have a block size */
842 if (!inode->i_sb->s_blocksize)
843 return -EINVAL;
844
845 return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
846
847 case FICLONE:
848 return ioctl_file_clone(dst_file: filp, srcfd: arg, off: 0, olen: 0, destoff: 0);
849
850 case FICLONERANGE:
851 return ioctl_file_clone_range(file: filp, argp);
852
853 case FIDEDUPERANGE:
854 return ioctl_file_dedupe_range(file: filp, argp);
855
856 case FIONREAD:
857 if (!S_ISREG(inode->i_mode))
858 return vfs_ioctl(filp, cmd, arg);
859
860 return put_user(i_size_read(inode) - filp->f_pos,
861 (int __user *)argp);
862
863 case FS_IOC_GETFLAGS:
864 return ioctl_getflags(file: filp, argp);
865
866 case FS_IOC_SETFLAGS:
867 return ioctl_setflags(file: filp, argp);
868
869 case FS_IOC_FSGETXATTR:
870 return ioctl_fsgetxattr(file: filp, argp);
871
872 case FS_IOC_FSSETXATTR:
873 return ioctl_fssetxattr(file: filp, argp);
874
875 case FS_IOC_GETFSUUID:
876 return ioctl_getfsuuid(file: filp, argp);
877
878 case FS_IOC_GETFSSYSFSPATH:
879 return ioctl_get_fs_sysfs_path(file: filp, argp);
880
881 default:
882 if (S_ISREG(inode->i_mode))
883 return file_ioctl(filp, cmd, p: argp);
884 break;
885 }
886
887 return -ENOIOCTLCMD;
888}
889
890SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
891{
892 struct fd f = fdget(fd);
893 int error;
894
895 if (!f.file)
896 return -EBADF;
897
898 error = security_file_ioctl(file: f.file, cmd, arg);
899 if (error)
900 goto out;
901
902 error = do_vfs_ioctl(filp: f.file, fd, cmd, arg);
903 if (error == -ENOIOCTLCMD)
904 error = vfs_ioctl(f.file, cmd, arg);
905
906out:
907 fdput(fd: f);
908 return error;
909}
910
911#ifdef CONFIG_COMPAT
912/**
913 * compat_ptr_ioctl - generic implementation of .compat_ioctl file operation
914 * @file: The file to operate on.
915 * @cmd: The ioctl command number.
916 * @arg: The argument to the ioctl.
917 *
918 * This is not normally called as a function, but instead set in struct
919 * file_operations as
920 *
921 * .compat_ioctl = compat_ptr_ioctl,
922 *
923 * On most architectures, the compat_ptr_ioctl() just passes all arguments
924 * to the corresponding ->ioctl handler. The exception is arch/s390, where
925 * compat_ptr() clears the top bit of a 32-bit pointer value, so user space
926 * pointers to the second 2GB alias the first 2GB, as is the case for
927 * native 32-bit s390 user space.
928 *
929 * The compat_ptr_ioctl() function must therefore be used only with ioctl
930 * functions that either ignore the argument or pass a pointer to a
931 * compatible data type.
932 *
933 * If any ioctl command handled by fops->unlocked_ioctl passes a plain
934 * integer instead of a pointer, or any of the passed data types
935 * is incompatible between 32-bit and 64-bit architectures, a proper
936 * handler is required instead of compat_ptr_ioctl.
937 */
938long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
939{
940 if (!file->f_op->unlocked_ioctl)
941 return -ENOIOCTLCMD;
942
943 return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(uptr: arg));
944}
945EXPORT_SYMBOL(compat_ptr_ioctl);
946
947COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
948 compat_ulong_t, arg)
949{
950 struct fd f = fdget(fd);
951 int error;
952
953 if (!f.file)
954 return -EBADF;
955
956 error = security_file_ioctl_compat(file: f.file, cmd, arg);
957 if (error)
958 goto out;
959
960 switch (cmd) {
961 /* FICLONE takes an int argument, so don't use compat_ptr() */
962 case FICLONE:
963 error = ioctl_file_clone(dst_file: f.file, srcfd: arg, off: 0, olen: 0, destoff: 0);
964 break;
965
966#if defined(CONFIG_X86_64)
967 /* these get messy on amd64 due to alignment differences */
968 case FS_IOC_RESVSP_32:
969 case FS_IOC_RESVSP64_32:
970 error = compat_ioctl_preallocate(file: f.file, mode: 0, argp: compat_ptr(uptr: arg));
971 break;
972 case FS_IOC_UNRESVSP_32:
973 case FS_IOC_UNRESVSP64_32:
974 error = compat_ioctl_preallocate(file: f.file, FALLOC_FL_PUNCH_HOLE,
975 argp: compat_ptr(uptr: arg));
976 break;
977 case FS_IOC_ZERO_RANGE_32:
978 error = compat_ioctl_preallocate(file: f.file, FALLOC_FL_ZERO_RANGE,
979 argp: compat_ptr(uptr: arg));
980 break;
981#endif
982
983 /*
984 * These access 32-bit values anyway so no further handling is
985 * necessary.
986 */
987 case FS_IOC32_GETFLAGS:
988 case FS_IOC32_SETFLAGS:
989 cmd = (cmd == FS_IOC32_GETFLAGS) ?
990 FS_IOC_GETFLAGS : FS_IOC_SETFLAGS;
991 fallthrough;
992 /*
993 * everything else in do_vfs_ioctl() takes either a compatible
994 * pointer argument or no argument -- call it with a modified
995 * argument.
996 */
997 default:
998 error = do_vfs_ioctl(filp: f.file, fd, cmd,
999 arg: (unsigned long)compat_ptr(uptr: arg));
1000 if (error != -ENOIOCTLCMD)
1001 break;
1002
1003 if (f.file->f_op->compat_ioctl)
1004 error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
1005 if (error == -ENOIOCTLCMD)
1006 error = -ENOTTY;
1007 break;
1008 }
1009
1010 out:
1011 fdput(fd: f);
1012
1013 return error;
1014}
1015#endif
1016

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source code of linux/fs/ioctl.c