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