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v6.8
  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(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);
 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(dest, &extent, 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(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(filp);
205	int error;
206
207	if (!inode->i_op->fiemap)
208		return -EOPNOTSUPP;
209
210	if (copy_from_user(&fiemap, ufiemap, 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(ufiemap, &fiemap, 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(srcfd);
235	loff_t cloned;
236	int ret;
237
238	if (!src_file.file)
239		return -EBADF;
240	cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff,
241				      olen, 0);
242	if (cloned < 0)
243		ret = cloned;
244	else if (olen && cloned != olen)
245		ret = -EINVAL;
246	else
247		ret = 0;
248	fdput(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(&args, argp, sizeof(args)))
258		return -EFAULT;
259	return ioctl_file_clone(file, args.src_fd, args.src_offset,
260				args.src_length, 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(filp);
273	struct space_resv sr;
274
275	if (copy_from_user(&sr, argp, 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(filp, mode | FALLOC_FL_KEEP_SIZE, sr.l_start,
292			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(file);
302	struct space_resv_32 sr;
303
304	if (copy_from_user(&sr, argp, 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 | FALLOC_FL_KEEP_SIZE, sr.l_start, 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, 0, p);
332	case FS_IOC_UNRESVSP:
333	case FS_IOC_UNRESVSP64:
334		return ioctl_preallocate(filp, FALLOC_FL_PUNCH_HOLE, p);
335	case FS_IOC_ZERO_RANGE:
336		return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, 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(&filp->f_lock);
357	if (on)
358		filp->f_flags |= flag;
359	else
360		filp->f_flags &= ~flag;
361	spin_unlock(&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(filp)->i_sb;
390
391	if (!ns_capable(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(sb, FREEZE_HOLDER_USERSPACE);
402}
403
404static int ioctl_fsthaw(struct file *filp)
405{
406	struct super_block *sb = file_inode(filp)->i_sb;
407
408	if (!ns_capable(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(sb, 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(same)) {
438		ret = PTR_ERR(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(argp, same, size);
449	if (ret)
450		ret = -EFAULT;
451
452out:
453	kfree(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(ufa, &xfa, 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(&xfa, ufa, 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, old_ma->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(make_kprojid(&init_user_ns, 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, 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, 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
766/*
767 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
768 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
769 *
770 * When you add any new common ioctls to the switches above and below,
771 * please ensure they have compatible arguments in compat mode.
 
 
 
772 */
773static int do_vfs_ioctl(struct file *filp, unsigned int fd,
774			unsigned int cmd, unsigned long arg)
775{
776	void __user *argp = (void __user *)arg;
777	struct inode *inode = file_inode(filp);
778
779	switch (cmd) {
780	case FIOCLEX:
781		set_close_on_exec(fd, 1);
782		return 0;
783
784	case FIONCLEX:
785		set_close_on_exec(fd, 0);
786		return 0;
787
788	case FIONBIO:
789		return ioctl_fionbio(filp, argp);
790
791	case FIOASYNC:
792		return ioctl_fioasync(fd, filp, argp);
793
794	case FIOQSIZE:
795		if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
796		    S_ISLNK(inode->i_mode)) {
797			loff_t res = inode_get_bytes(inode);
798			return copy_to_user(argp, &res, sizeof(res)) ?
799					    -EFAULT : 0;
800		}
801
802		return -ENOTTY;
803
804	case FIFREEZE:
805		return ioctl_fsfreeze(filp);
806
807	case FITHAW:
808		return ioctl_fsthaw(filp);
809
810	case FS_IOC_FIEMAP:
811		return ioctl_fiemap(filp, argp);
812
813	case FIGETBSZ:
814		/* anon_bdev filesystems may not have a block size */
815		if (!inode->i_sb->s_blocksize)
816			return -EINVAL;
817
818		return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
819
820	case FICLONE:
821		return ioctl_file_clone(filp, arg, 0, 0, 0);
822
823	case FICLONERANGE:
824		return ioctl_file_clone_range(filp, argp);
825
826	case FIDEDUPERANGE:
827		return ioctl_file_dedupe_range(filp, argp);
828
829	case FIONREAD:
830		if (!S_ISREG(inode->i_mode))
831			return vfs_ioctl(filp, cmd, arg);
832
833		return put_user(i_size_read(inode) - filp->f_pos,
834				(int __user *)argp);
835
836	case FS_IOC_GETFLAGS:
837		return ioctl_getflags(filp, argp);
838
839	case FS_IOC_SETFLAGS:
840		return ioctl_setflags(filp, argp);
841
842	case FS_IOC_FSGETXATTR:
843		return ioctl_fsgetxattr(filp, argp);
844
845	case FS_IOC_FSSETXATTR:
846		return ioctl_fssetxattr(filp, argp);
847
 
 
 
 
 
 
848	default:
849		if (S_ISREG(inode->i_mode))
850			return file_ioctl(filp, cmd, argp);
851		break;
852	}
853
854	return -ENOIOCTLCMD;
855}
856
857SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
858{
859	struct fd f = fdget(fd);
860	int error;
861
862	if (!f.file)
863		return -EBADF;
864
865	error = security_file_ioctl(f.file, cmd, arg);
866	if (error)
867		goto out;
868
869	error = do_vfs_ioctl(f.file, fd, cmd, arg);
870	if (error == -ENOIOCTLCMD)
871		error = vfs_ioctl(f.file, cmd, arg);
872
873out:
874	fdput(f);
875	return error;
876}
877
878#ifdef CONFIG_COMPAT
879/**
880 * compat_ptr_ioctl - generic implementation of .compat_ioctl file operation
881 * @file: The file to operate on.
882 * @cmd: The ioctl command number.
883 * @arg: The argument to the ioctl.
884 *
885 * This is not normally called as a function, but instead set in struct
886 * file_operations as
887 *
888 *     .compat_ioctl = compat_ptr_ioctl,
889 *
890 * On most architectures, the compat_ptr_ioctl() just passes all arguments
891 * to the corresponding ->ioctl handler. The exception is arch/s390, where
892 * compat_ptr() clears the top bit of a 32-bit pointer value, so user space
893 * pointers to the second 2GB alias the first 2GB, as is the case for
894 * native 32-bit s390 user space.
895 *
896 * The compat_ptr_ioctl() function must therefore be used only with ioctl
897 * functions that either ignore the argument or pass a pointer to a
898 * compatible data type.
899 *
900 * If any ioctl command handled by fops->unlocked_ioctl passes a plain
901 * integer instead of a pointer, or any of the passed data types
902 * is incompatible between 32-bit and 64-bit architectures, a proper
903 * handler is required instead of compat_ptr_ioctl.
904 */
905long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
906{
907	if (!file->f_op->unlocked_ioctl)
908		return -ENOIOCTLCMD;
909
910	return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
911}
912EXPORT_SYMBOL(compat_ptr_ioctl);
913
914COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
915		       compat_ulong_t, arg)
916{
917	struct fd f = fdget(fd);
918	int error;
919
920	if (!f.file)
921		return -EBADF;
922
923	error = security_file_ioctl_compat(f.file, cmd, arg);
924	if (error)
925		goto out;
926
927	switch (cmd) {
928	/* FICLONE takes an int argument, so don't use compat_ptr() */
929	case FICLONE:
930		error = ioctl_file_clone(f.file, arg, 0, 0, 0);
931		break;
932
933#if defined(CONFIG_X86_64)
934	/* these get messy on amd64 due to alignment differences */
935	case FS_IOC_RESVSP_32:
936	case FS_IOC_RESVSP64_32:
937		error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
938		break;
939	case FS_IOC_UNRESVSP_32:
940	case FS_IOC_UNRESVSP64_32:
941		error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
942				compat_ptr(arg));
943		break;
944	case FS_IOC_ZERO_RANGE_32:
945		error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
946				compat_ptr(arg));
947		break;
948#endif
949
950	/*
951	 * These access 32-bit values anyway so no further handling is
952	 * necessary.
953	 */
954	case FS_IOC32_GETFLAGS:
955	case FS_IOC32_SETFLAGS:
956		cmd = (cmd == FS_IOC32_GETFLAGS) ?
957			FS_IOC_GETFLAGS : FS_IOC_SETFLAGS;
958		fallthrough;
959	/*
960	 * everything else in do_vfs_ioctl() takes either a compatible
961	 * pointer argument or no argument -- call it with a modified
962	 * argument.
963	 */
964	default:
965		error = do_vfs_ioctl(f.file, fd, cmd,
966				     (unsigned long)compat_ptr(arg));
967		if (error != -ENOIOCTLCMD)
968			break;
969
970		if (f.file->f_op->compat_ioctl)
971			error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
972		if (error == -ENOIOCTLCMD)
973			error = -ENOTTY;
974		break;
975	}
976
977 out:
978	fdput(f);
979
980	return error;
981}
982#endif
v6.13.7
   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(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);
  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(dest, &extent, 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(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(filp);
 205	int error;
 206
 207	if (!inode->i_op->fiemap)
 208		return -EOPNOTSUPP;
 209
 210	if (copy_from_user(&fiemap, ufiemap, 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(ufiemap, &fiemap, 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	CLASS(fd, src_file)(srcfd);
 235	loff_t cloned;
 236	int ret;
 237
 238	if (fd_empty(src_file))
 239		return -EBADF;
 240	cloned = vfs_clone_file_range(fd_file(src_file), off, dst_file, destoff,
 241				      olen, 0);
 242	if (cloned < 0)
 243		ret = cloned;
 244	else if (olen && cloned != olen)
 245		ret = -EINVAL;
 246	else
 247		ret = 0;
 
 248	return ret;
 249}
 250
 251static long ioctl_file_clone_range(struct file *file,
 252				   struct file_clone_range __user *argp)
 253{
 254	struct file_clone_range args;
 255
 256	if (copy_from_user(&args, argp, sizeof(args)))
 257		return -EFAULT;
 258	return ioctl_file_clone(file, args.src_fd, args.src_offset,
 259				args.src_length, args.dest_offset);
 260}
 261
 262/*
 263 * This provides compatibility with legacy XFS pre-allocation ioctls
 264 * which predate the fallocate syscall.
 265 *
 266 * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
 267 * are used here, rest are ignored.
 268 */
 269static int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
 270{
 271	struct inode *inode = file_inode(filp);
 272	struct space_resv sr;
 273
 274	if (copy_from_user(&sr, argp, sizeof(sr)))
 275		return -EFAULT;
 276
 277	switch (sr.l_whence) {
 278	case SEEK_SET:
 279		break;
 280	case SEEK_CUR:
 281		sr.l_start += filp->f_pos;
 282		break;
 283	case SEEK_END:
 284		sr.l_start += i_size_read(inode);
 285		break;
 286	default:
 287		return -EINVAL;
 288	}
 289
 290	return vfs_fallocate(filp, mode | FALLOC_FL_KEEP_SIZE, sr.l_start,
 291			sr.l_len);
 292}
 293
 294/* on ia32 l_start is on a 32-bit boundary */
 295#if defined CONFIG_COMPAT && defined(CONFIG_X86_64)
 296/* just account for different alignment */
 297static int compat_ioctl_preallocate(struct file *file, int mode,
 298				    struct space_resv_32 __user *argp)
 299{
 300	struct inode *inode = file_inode(file);
 301	struct space_resv_32 sr;
 302
 303	if (copy_from_user(&sr, argp, sizeof(sr)))
 304		return -EFAULT;
 305
 306	switch (sr.l_whence) {
 307	case SEEK_SET:
 308		break;
 309	case SEEK_CUR:
 310		sr.l_start += file->f_pos;
 311		break;
 312	case SEEK_END:
 313		sr.l_start += i_size_read(inode);
 314		break;
 315	default:
 316		return -EINVAL;
 317	}
 318
 319	return vfs_fallocate(file, mode | FALLOC_FL_KEEP_SIZE, sr.l_start, sr.l_len);
 320}
 321#endif
 322
 323static int file_ioctl(struct file *filp, unsigned int cmd, int __user *p)
 324{
 325	switch (cmd) {
 326	case FIBMAP:
 327		return ioctl_fibmap(filp, p);
 328	case FS_IOC_RESVSP:
 329	case FS_IOC_RESVSP64:
 330		return ioctl_preallocate(filp, 0, p);
 331	case FS_IOC_UNRESVSP:
 332	case FS_IOC_UNRESVSP64:
 333		return ioctl_preallocate(filp, FALLOC_FL_PUNCH_HOLE, p);
 334	case FS_IOC_ZERO_RANGE:
 335		return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, p);
 336	}
 337
 338	return -ENOIOCTLCMD;
 339}
 340
 341static int ioctl_fionbio(struct file *filp, int __user *argp)
 342{
 343	unsigned int flag;
 344	int on, error;
 345
 346	error = get_user(on, argp);
 347	if (error)
 348		return error;
 349	flag = O_NONBLOCK;
 350#ifdef __sparc__
 351	/* SunOS compatibility item. */
 352	if (O_NONBLOCK != O_NDELAY)
 353		flag |= O_NDELAY;
 354#endif
 355	spin_lock(&filp->f_lock);
 356	if (on)
 357		filp->f_flags |= flag;
 358	else
 359		filp->f_flags &= ~flag;
 360	spin_unlock(&filp->f_lock);
 361	return error;
 362}
 363
 364static int ioctl_fioasync(unsigned int fd, struct file *filp,
 365			  int __user *argp)
 366{
 367	unsigned int flag;
 368	int on, error;
 369
 370	error = get_user(on, argp);
 371	if (error)
 372		return error;
 373	flag = on ? FASYNC : 0;
 374
 375	/* Did FASYNC state change ? */
 376	if ((flag ^ filp->f_flags) & FASYNC) {
 377		if (filp->f_op->fasync)
 378			/* fasync() adjusts filp->f_flags */
 379			error = filp->f_op->fasync(fd, filp, on);
 380		else
 381			error = -ENOTTY;
 382	}
 383	return error < 0 ? error : 0;
 384}
 385
 386static int ioctl_fsfreeze(struct file *filp)
 387{
 388	struct super_block *sb = file_inode(filp)->i_sb;
 389
 390	if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
 391		return -EPERM;
 392
 393	/* If filesystem doesn't support freeze feature, return. */
 394	if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
 395		return -EOPNOTSUPP;
 396
 397	/* Freeze */
 398	if (sb->s_op->freeze_super)
 399		return sb->s_op->freeze_super(sb, FREEZE_HOLDER_USERSPACE);
 400	return freeze_super(sb, FREEZE_HOLDER_USERSPACE);
 401}
 402
 403static int ioctl_fsthaw(struct file *filp)
 404{
 405	struct super_block *sb = file_inode(filp)->i_sb;
 406
 407	if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
 408		return -EPERM;
 409
 410	/* Thaw */
 411	if (sb->s_op->thaw_super)
 412		return sb->s_op->thaw_super(sb, FREEZE_HOLDER_USERSPACE);
 413	return thaw_super(sb, FREEZE_HOLDER_USERSPACE);
 414}
 415
 416static int ioctl_file_dedupe_range(struct file *file,
 417				   struct file_dedupe_range __user *argp)
 418{
 419	struct file_dedupe_range *same = NULL;
 420	int ret;
 421	unsigned long size;
 422	u16 count;
 423
 424	if (get_user(count, &argp->dest_count)) {
 425		ret = -EFAULT;
 426		goto out;
 427	}
 428
 429	size = offsetof(struct file_dedupe_range, info[count]);
 430	if (size > PAGE_SIZE) {
 431		ret = -ENOMEM;
 432		goto out;
 433	}
 434
 435	same = memdup_user(argp, size);
 436	if (IS_ERR(same)) {
 437		ret = PTR_ERR(same);
 438		same = NULL;
 439		goto out;
 440	}
 441
 442	same->dest_count = count;
 443	ret = vfs_dedupe_file_range(file, same);
 444	if (ret)
 445		goto out;
 446
 447	ret = copy_to_user(argp, same, size);
 448	if (ret)
 449		ret = -EFAULT;
 450
 451out:
 452	kfree(same);
 453	return ret;
 454}
 455
 456/**
 457 * fileattr_fill_xflags - initialize fileattr with xflags
 458 * @fa:		fileattr pointer
 459 * @xflags:	FS_XFLAG_* flags
 460 *
 461 * Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags).  All
 462 * other fields are zeroed.
 463 */
 464void fileattr_fill_xflags(struct fileattr *fa, u32 xflags)
 465{
 466	memset(fa, 0, sizeof(*fa));
 467	fa->fsx_valid = true;
 468	fa->fsx_xflags = xflags;
 469	if (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)
 470		fa->flags |= FS_IMMUTABLE_FL;
 471	if (fa->fsx_xflags & FS_XFLAG_APPEND)
 472		fa->flags |= FS_APPEND_FL;
 473	if (fa->fsx_xflags & FS_XFLAG_SYNC)
 474		fa->flags |= FS_SYNC_FL;
 475	if (fa->fsx_xflags & FS_XFLAG_NOATIME)
 476		fa->flags |= FS_NOATIME_FL;
 477	if (fa->fsx_xflags & FS_XFLAG_NODUMP)
 478		fa->flags |= FS_NODUMP_FL;
 479	if (fa->fsx_xflags & FS_XFLAG_DAX)
 480		fa->flags |= FS_DAX_FL;
 481	if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
 482		fa->flags |= FS_PROJINHERIT_FL;
 483}
 484EXPORT_SYMBOL(fileattr_fill_xflags);
 485
 486/**
 487 * fileattr_fill_flags - initialize fileattr with flags
 488 * @fa:		fileattr pointer
 489 * @flags:	FS_*_FL flags
 490 *
 491 * Set ->flags, ->flags_valid and ->fsx_xflags (translated flags).
 492 * All other fields are zeroed.
 493 */
 494void fileattr_fill_flags(struct fileattr *fa, u32 flags)
 495{
 496	memset(fa, 0, sizeof(*fa));
 497	fa->flags_valid = true;
 498	fa->flags = flags;
 499	if (fa->flags & FS_SYNC_FL)
 500		fa->fsx_xflags |= FS_XFLAG_SYNC;
 501	if (fa->flags & FS_IMMUTABLE_FL)
 502		fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
 503	if (fa->flags & FS_APPEND_FL)
 504		fa->fsx_xflags |= FS_XFLAG_APPEND;
 505	if (fa->flags & FS_NODUMP_FL)
 506		fa->fsx_xflags |= FS_XFLAG_NODUMP;
 507	if (fa->flags & FS_NOATIME_FL)
 508		fa->fsx_xflags |= FS_XFLAG_NOATIME;
 509	if (fa->flags & FS_DAX_FL)
 510		fa->fsx_xflags |= FS_XFLAG_DAX;
 511	if (fa->flags & FS_PROJINHERIT_FL)
 512		fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
 513}
 514EXPORT_SYMBOL(fileattr_fill_flags);
 515
 516/**
 517 * vfs_fileattr_get - retrieve miscellaneous file attributes
 518 * @dentry:	the object to retrieve from
 519 * @fa:		fileattr pointer
 520 *
 521 * Call i_op->fileattr_get() callback, if exists.
 522 *
 523 * Return: 0 on success, or a negative error on failure.
 524 */
 525int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
 526{
 527	struct inode *inode = d_inode(dentry);
 528
 529	if (!inode->i_op->fileattr_get)
 530		return -ENOIOCTLCMD;
 531
 532	return inode->i_op->fileattr_get(dentry, fa);
 533}
 534EXPORT_SYMBOL(vfs_fileattr_get);
 535
 536/**
 537 * copy_fsxattr_to_user - copy fsxattr to userspace.
 538 * @fa:		fileattr pointer
 539 * @ufa:	fsxattr user pointer
 540 *
 541 * Return: 0 on success, or -EFAULT on failure.
 542 */
 543int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa)
 544{
 545	struct fsxattr xfa;
 546
 547	memset(&xfa, 0, sizeof(xfa));
 548	xfa.fsx_xflags = fa->fsx_xflags;
 549	xfa.fsx_extsize = fa->fsx_extsize;
 550	xfa.fsx_nextents = fa->fsx_nextents;
 551	xfa.fsx_projid = fa->fsx_projid;
 552	xfa.fsx_cowextsize = fa->fsx_cowextsize;
 553
 554	if (copy_to_user(ufa, &xfa, sizeof(xfa)))
 555		return -EFAULT;
 556
 557	return 0;
 558}
 559EXPORT_SYMBOL(copy_fsxattr_to_user);
 560
 561static int copy_fsxattr_from_user(struct fileattr *fa,
 562				  struct fsxattr __user *ufa)
 563{
 564	struct fsxattr xfa;
 565
 566	if (copy_from_user(&xfa, ufa, sizeof(xfa)))
 567		return -EFAULT;
 568
 569	fileattr_fill_xflags(fa, xfa.fsx_xflags);
 570	fa->fsx_extsize = xfa.fsx_extsize;
 571	fa->fsx_nextents = xfa.fsx_nextents;
 572	fa->fsx_projid = xfa.fsx_projid;
 573	fa->fsx_cowextsize = xfa.fsx_cowextsize;
 574
 575	return 0;
 576}
 577
 578/*
 579 * Generic function to check FS_IOC_FSSETXATTR/FS_IOC_SETFLAGS values and reject
 580 * any invalid configurations.
 581 *
 582 * Note: must be called with inode lock held.
 583 */
 584static int fileattr_set_prepare(struct inode *inode,
 585			      const struct fileattr *old_ma,
 586			      struct fileattr *fa)
 587{
 588	int err;
 589
 590	/*
 591	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
 592	 * the relevant capability.
 593	 */
 594	if ((fa->flags ^ old_ma->flags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) &&
 595	    !capable(CAP_LINUX_IMMUTABLE))
 596		return -EPERM;
 597
 598	err = fscrypt_prepare_setflags(inode, old_ma->flags, fa->flags);
 599	if (err)
 600		return err;
 601
 602	/*
 603	 * Project Quota ID state is only allowed to change from within the init
 604	 * namespace. Enforce that restriction only if we are trying to change
 605	 * the quota ID state. Everything else is allowed in user namespaces.
 606	 */
 607	if (current_user_ns() != &init_user_ns) {
 608		if (old_ma->fsx_projid != fa->fsx_projid)
 609			return -EINVAL;
 610		if ((old_ma->fsx_xflags ^ fa->fsx_xflags) &
 611				FS_XFLAG_PROJINHERIT)
 612			return -EINVAL;
 613	} else {
 614		/*
 615		 * Caller is allowed to change the project ID. If it is being
 616		 * changed, make sure that the new value is valid.
 617		 */
 618		if (old_ma->fsx_projid != fa->fsx_projid &&
 619		    !projid_valid(make_kprojid(&init_user_ns, fa->fsx_projid)))
 620			return -EINVAL;
 621	}
 622
 623	/* Check extent size hints. */
 624	if ((fa->fsx_xflags & FS_XFLAG_EXTSIZE) && !S_ISREG(inode->i_mode))
 625		return -EINVAL;
 626
 627	if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) &&
 628			!S_ISDIR(inode->i_mode))
 629		return -EINVAL;
 630
 631	if ((fa->fsx_xflags & FS_XFLAG_COWEXTSIZE) &&
 632	    !S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
 633		return -EINVAL;
 634
 635	/*
 636	 * It is only valid to set the DAX flag on regular files and
 637	 * directories on filesystems.
 638	 */
 639	if ((fa->fsx_xflags & FS_XFLAG_DAX) &&
 640	    !(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 641		return -EINVAL;
 642
 643	/* Extent size hints of zero turn off the flags. */
 644	if (fa->fsx_extsize == 0)
 645		fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);
 646	if (fa->fsx_cowextsize == 0)
 647		fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
 648
 649	return 0;
 650}
 651
 652/**
 653 * vfs_fileattr_set - change miscellaneous file attributes
 654 * @idmap:	idmap of the mount
 655 * @dentry:	the object to change
 656 * @fa:		fileattr pointer
 657 *
 658 * After verifying permissions, call i_op->fileattr_set() callback, if
 659 * exists.
 660 *
 661 * Verifying attributes involves retrieving current attributes with
 662 * i_op->fileattr_get(), this also allows initializing attributes that have
 663 * not been set by the caller to current values.  Inode lock is held
 664 * thoughout to prevent racing with another instance.
 665 *
 666 * Return: 0 on success, or a negative error on failure.
 667 */
 668int vfs_fileattr_set(struct mnt_idmap *idmap, struct dentry *dentry,
 669		     struct fileattr *fa)
 670{
 671	struct inode *inode = d_inode(dentry);
 672	struct fileattr old_ma = {};
 673	int err;
 674
 675	if (!inode->i_op->fileattr_set)
 676		return -ENOIOCTLCMD;
 677
 678	if (!inode_owner_or_capable(idmap, inode))
 679		return -EPERM;
 680
 681	inode_lock(inode);
 682	err = vfs_fileattr_get(dentry, &old_ma);
 683	if (!err) {
 684		/* initialize missing bits from old_ma */
 685		if (fa->flags_valid) {
 686			fa->fsx_xflags |= old_ma.fsx_xflags & ~FS_XFLAG_COMMON;
 687			fa->fsx_extsize = old_ma.fsx_extsize;
 688			fa->fsx_nextents = old_ma.fsx_nextents;
 689			fa->fsx_projid = old_ma.fsx_projid;
 690			fa->fsx_cowextsize = old_ma.fsx_cowextsize;
 691		} else {
 692			fa->flags |= old_ma.flags & ~FS_COMMON_FL;
 693		}
 694		err = fileattr_set_prepare(inode, &old_ma, fa);
 695		if (!err)
 696			err = inode->i_op->fileattr_set(idmap, dentry, fa);
 697	}
 698	inode_unlock(inode);
 699
 700	return err;
 701}
 702EXPORT_SYMBOL(vfs_fileattr_set);
 703
 704static int ioctl_getflags(struct file *file, unsigned int __user *argp)
 705{
 706	struct fileattr fa = { .flags_valid = true }; /* hint only */
 707	int err;
 708
 709	err = vfs_fileattr_get(file->f_path.dentry, &fa);
 710	if (!err)
 711		err = put_user(fa.flags, argp);
 712	return err;
 713}
 714
 715static int ioctl_setflags(struct file *file, unsigned int __user *argp)
 716{
 717	struct mnt_idmap *idmap = file_mnt_idmap(file);
 718	struct dentry *dentry = file->f_path.dentry;
 719	struct fileattr fa;
 720	unsigned int flags;
 721	int err;
 722
 723	err = get_user(flags, argp);
 724	if (!err) {
 725		err = mnt_want_write_file(file);
 726		if (!err) {
 727			fileattr_fill_flags(&fa, flags);
 728			err = vfs_fileattr_set(idmap, dentry, &fa);
 729			mnt_drop_write_file(file);
 730		}
 731	}
 732	return err;
 733}
 734
 735static int ioctl_fsgetxattr(struct file *file, void __user *argp)
 736{
 737	struct fileattr fa = { .fsx_valid = true }; /* hint only */
 738	int err;
 739
 740	err = vfs_fileattr_get(file->f_path.dentry, &fa);
 741	if (!err)
 742		err = copy_fsxattr_to_user(&fa, argp);
 743
 744	return err;
 745}
 746
 747static int ioctl_fssetxattr(struct file *file, void __user *argp)
 748{
 749	struct mnt_idmap *idmap = file_mnt_idmap(file);
 750	struct dentry *dentry = file->f_path.dentry;
 751	struct fileattr fa;
 752	int err;
 753
 754	err = copy_fsxattr_from_user(&fa, argp);
 755	if (!err) {
 756		err = mnt_want_write_file(file);
 757		if (!err) {
 758			err = vfs_fileattr_set(idmap, dentry, &fa);
 759			mnt_drop_write_file(file);
 760		}
 761	}
 762	return err;
 763}
 764
 765static int ioctl_getfsuuid(struct file *file, void __user *argp)
 766{
 767	struct super_block *sb = file_inode(file)->i_sb;
 768	struct fsuuid2 u = { .len = sb->s_uuid_len, };
 769
 770	if (!sb->s_uuid_len)
 771		return -ENOTTY;
 772
 773	memcpy(&u.uuid[0], &sb->s_uuid, sb->s_uuid_len);
 774
 775	return copy_to_user(argp, &u, sizeof(u)) ? -EFAULT : 0;
 776}
 777
 778static int ioctl_get_fs_sysfs_path(struct file *file, void __user *argp)
 779{
 780	struct super_block *sb = file_inode(file)->i_sb;
 781
 782	if (!strlen(sb->s_sysfs_name))
 783		return -ENOTTY;
 784
 785	struct fs_sysfs_path u = {};
 786
 787	u.len = scnprintf(u.name, sizeof(u.name), "%s/%s", sb->s_type->name, sb->s_sysfs_name);
 788
 789	return copy_to_user(argp, &u, sizeof(u)) ? -EFAULT : 0;
 790}
 791
 792/*
 793 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
 794 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
 795 *
 796 * When you add any new common ioctls to the switches above and below,
 797 * please ensure they have compatible arguments in compat mode.
 798 *
 799 * The LSM mailing list should also be notified of any command additions or
 800 * changes, as specific LSMs may be affected.
 801 */
 802static int do_vfs_ioctl(struct file *filp, unsigned int fd,
 803			unsigned int cmd, unsigned long arg)
 804{
 805	void __user *argp = (void __user *)arg;
 806	struct inode *inode = file_inode(filp);
 807
 808	switch (cmd) {
 809	case FIOCLEX:
 810		set_close_on_exec(fd, 1);
 811		return 0;
 812
 813	case FIONCLEX:
 814		set_close_on_exec(fd, 0);
 815		return 0;
 816
 817	case FIONBIO:
 818		return ioctl_fionbio(filp, argp);
 819
 820	case FIOASYNC:
 821		return ioctl_fioasync(fd, filp, argp);
 822
 823	case FIOQSIZE:
 824		if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
 825		    S_ISLNK(inode->i_mode)) {
 826			loff_t res = inode_get_bytes(inode);
 827			return copy_to_user(argp, &res, sizeof(res)) ?
 828					    -EFAULT : 0;
 829		}
 830
 831		return -ENOTTY;
 832
 833	case FIFREEZE:
 834		return ioctl_fsfreeze(filp);
 835
 836	case FITHAW:
 837		return ioctl_fsthaw(filp);
 838
 839	case FS_IOC_FIEMAP:
 840		return ioctl_fiemap(filp, argp);
 841
 842	case FIGETBSZ:
 843		/* anon_bdev filesystems may not have a block size */
 844		if (!inode->i_sb->s_blocksize)
 845			return -EINVAL;
 846
 847		return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
 848
 849	case FICLONE:
 850		return ioctl_file_clone(filp, arg, 0, 0, 0);
 851
 852	case FICLONERANGE:
 853		return ioctl_file_clone_range(filp, argp);
 854
 855	case FIDEDUPERANGE:
 856		return ioctl_file_dedupe_range(filp, argp);
 857
 858	case FIONREAD:
 859		if (!S_ISREG(inode->i_mode))
 860			return vfs_ioctl(filp, cmd, arg);
 861
 862		return put_user(i_size_read(inode) - filp->f_pos,
 863				(int __user *)argp);
 864
 865	case FS_IOC_GETFLAGS:
 866		return ioctl_getflags(filp, argp);
 867
 868	case FS_IOC_SETFLAGS:
 869		return ioctl_setflags(filp, argp);
 870
 871	case FS_IOC_FSGETXATTR:
 872		return ioctl_fsgetxattr(filp, argp);
 873
 874	case FS_IOC_FSSETXATTR:
 875		return ioctl_fssetxattr(filp, argp);
 876
 877	case FS_IOC_GETFSUUID:
 878		return ioctl_getfsuuid(filp, argp);
 879
 880	case FS_IOC_GETFSSYSFSPATH:
 881		return ioctl_get_fs_sysfs_path(filp, argp);
 882
 883	default:
 884		if (S_ISREG(inode->i_mode))
 885			return file_ioctl(filp, cmd, argp);
 886		break;
 887	}
 888
 889	return -ENOIOCTLCMD;
 890}
 891
 892SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
 893{
 894	CLASS(fd, f)(fd);
 895	int error;
 896
 897	if (fd_empty(f))
 898		return -EBADF;
 899
 900	error = security_file_ioctl(fd_file(f), cmd, arg);
 901	if (error)
 902		return error;
 903
 904	error = do_vfs_ioctl(fd_file(f), fd, cmd, arg);
 905	if (error == -ENOIOCTLCMD)
 906		error = vfs_ioctl(fd_file(f), cmd, arg);
 907
 
 
 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(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	CLASS(fd, f)(fd);
 951	int error;
 952
 953	if (fd_empty(f))
 954		return -EBADF;
 955
 956	error = security_file_ioctl_compat(fd_file(f), cmd, arg);
 957	if (error)
 958		return error;
 959
 960	switch (cmd) {
 961	/* FICLONE takes an int argument, so don't use compat_ptr() */
 962	case FICLONE:
 963		error = ioctl_file_clone(fd_file(f), arg, 0, 0, 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(fd_file(f), 0, compat_ptr(arg));
 971		break;
 972	case FS_IOC_UNRESVSP_32:
 973	case FS_IOC_UNRESVSP64_32:
 974		error = compat_ioctl_preallocate(fd_file(f), FALLOC_FL_PUNCH_HOLE,
 975				compat_ptr(arg));
 976		break;
 977	case FS_IOC_ZERO_RANGE_32:
 978		error = compat_ioctl_preallocate(fd_file(f), FALLOC_FL_ZERO_RANGE,
 979				compat_ptr(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(fd_file(f), fd, cmd,
 999				     (unsigned long)compat_ptr(arg));
1000		if (error != -ENOIOCTLCMD)
1001			break;
1002
1003		if (fd_file(f)->f_op->compat_ioctl)
1004			error = fd_file(f)->f_op->compat_ioctl(fd_file(f), cmd, arg);
1005		if (error == -ENOIOCTLCMD)
1006			error = -ENOTTY;
1007		break;
1008	}
 
 
 
 
1009	return error;
1010}
1011#endif