xref: /linux/fs/f2fs/xattr.c (revision cb015814f8b6eebcbb8e46e111d108892c5e6821)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * fs/f2fs/xattr.c
4  *
5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6  *             http://www.samsung.com/
7  *
8  * Portions of this code from linux/fs/ext2/xattr.c
9  *
10  * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
11  *
12  * Fix by Harrison Xing <harrison@mountainviewdata.com>.
13  * Extended attributes for symlinks and special files added per
14  *  suggestion of Luka Renko <luka.renko@hermes.si>.
15  * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
16  *  Red Hat Inc.
17  */
18 #include <linux/rwsem.h>
19 #include <linux/f2fs_fs.h>
20 #include <linux/security.h>
21 #include <linux/posix_acl_xattr.h>
22 #include "f2fs.h"
23 #include "xattr.h"
24 #include "segment.h"
25 
26 static struct kmem_cache *inline_xattr_slab;
xattr_alloc(struct f2fs_sb_info * sbi,int size,bool * is_inline)27 static void *xattr_alloc(struct f2fs_sb_info *sbi, int size, bool *is_inline)
28 {
29 	if (likely(size == DEFAULT_XATTR_SLAB_SIZE)) {
30 		*is_inline = true;
31 		return f2fs_kmem_cache_alloc(inline_xattr_slab,
32 					GFP_F2FS_ZERO, false, sbi);
33 	}
34 	*is_inline = false;
35 	return f2fs_kzalloc(sbi, size, GFP_NOFS);
36 }
37 
xattr_free(struct f2fs_sb_info * sbi,void * xattr_addr,bool is_inline)38 static void xattr_free(struct f2fs_sb_info *sbi, void *xattr_addr,
39 							bool is_inline)
40 {
41 	if (is_inline)
42 		kmem_cache_free(inline_xattr_slab, xattr_addr);
43 	else
44 		kfree(xattr_addr);
45 }
46 
f2fs_xattr_generic_get(const struct xattr_handler * handler,struct dentry * unused,struct inode * inode,const char * name,void * buffer,size_t size)47 static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
48 		struct dentry *unused, struct inode *inode,
49 		const char *name, void *buffer, size_t size)
50 {
51 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
52 
53 	switch (handler->flags) {
54 	case F2FS_XATTR_INDEX_USER:
55 		if (!test_opt(sbi, XATTR_USER))
56 			return -EOPNOTSUPP;
57 		break;
58 	case F2FS_XATTR_INDEX_TRUSTED:
59 	case F2FS_XATTR_INDEX_SECURITY:
60 		break;
61 	default:
62 		return -EINVAL;
63 	}
64 	return f2fs_getxattr(inode, handler->flags, name,
65 			     buffer, size, NULL);
66 }
67 
f2fs_xattr_generic_set(const struct xattr_handler * handler,struct mnt_idmap * idmap,struct dentry * unused,struct inode * inode,const char * name,const void * value,size_t size,int flags)68 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
69 		struct mnt_idmap *idmap,
70 		struct dentry *unused, struct inode *inode,
71 		const char *name, const void *value,
72 		size_t size, int flags)
73 {
74 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
75 
76 	switch (handler->flags) {
77 	case F2FS_XATTR_INDEX_USER:
78 		if (!test_opt(sbi, XATTR_USER))
79 			return -EOPNOTSUPP;
80 		break;
81 	case F2FS_XATTR_INDEX_TRUSTED:
82 	case F2FS_XATTR_INDEX_SECURITY:
83 		break;
84 	default:
85 		return -EINVAL;
86 	}
87 	return f2fs_setxattr(inode, handler->flags, name,
88 					value, size, NULL, flags);
89 }
90 
f2fs_xattr_user_list(struct dentry * dentry)91 static bool f2fs_xattr_user_list(struct dentry *dentry)
92 {
93 	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
94 
95 	return test_opt(sbi, XATTR_USER);
96 }
97 
f2fs_xattr_trusted_list(struct dentry * dentry)98 static bool f2fs_xattr_trusted_list(struct dentry *dentry)
99 {
100 	return capable(CAP_SYS_ADMIN);
101 }
102 
f2fs_xattr_advise_get(const struct xattr_handler * handler,struct dentry * unused,struct inode * inode,const char * name,void * buffer,size_t size)103 static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
104 		struct dentry *unused, struct inode *inode,
105 		const char *name, void *buffer, size_t size)
106 {
107 	if (buffer)
108 		*((char *)buffer) = F2FS_I(inode)->i_advise;
109 	return sizeof(char);
110 }
111 
f2fs_xattr_advise_set(const struct xattr_handler * handler,struct mnt_idmap * idmap,struct dentry * unused,struct inode * inode,const char * name,const void * value,size_t size,int flags)112 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
113 		struct mnt_idmap *idmap,
114 		struct dentry *unused, struct inode *inode,
115 		const char *name, const void *value,
116 		size_t size, int flags)
117 {
118 	unsigned char old_advise = F2FS_I(inode)->i_advise;
119 	unsigned char new_advise;
120 
121 	if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
122 		return -EPERM;
123 	if (value == NULL)
124 		return -EINVAL;
125 
126 	new_advise = *(char *)value;
127 	if (new_advise & ~FADVISE_MODIFIABLE_BITS)
128 		return -EINVAL;
129 
130 	new_advise = new_advise & FADVISE_MODIFIABLE_BITS;
131 	new_advise |= old_advise & ~FADVISE_MODIFIABLE_BITS;
132 
133 	F2FS_I(inode)->i_advise = new_advise;
134 	f2fs_mark_inode_dirty_sync(inode, true);
135 	return 0;
136 }
137 
138 #ifdef CONFIG_F2FS_FS_SECURITY
f2fs_initxattrs(struct inode * inode,const struct xattr * xattr_array,void * folio)139 static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
140 		void *folio)
141 {
142 	const struct xattr *xattr;
143 	int err = 0;
144 
145 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
146 		err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
147 				xattr->name, xattr->value,
148 				xattr->value_len, folio, 0);
149 		if (err < 0)
150 			break;
151 	}
152 	return err;
153 }
154 
f2fs_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,struct folio * ifolio)155 int f2fs_init_security(struct inode *inode, struct inode *dir,
156 				const struct qstr *qstr, struct folio *ifolio)
157 {
158 	return security_inode_init_security(inode, dir, qstr,
159 				f2fs_initxattrs, ifolio);
160 }
161 #endif
162 
163 const struct xattr_handler f2fs_xattr_user_handler = {
164 	.prefix	= XATTR_USER_PREFIX,
165 	.flags	= F2FS_XATTR_INDEX_USER,
166 	.list	= f2fs_xattr_user_list,
167 	.get	= f2fs_xattr_generic_get,
168 	.set	= f2fs_xattr_generic_set,
169 };
170 
171 const struct xattr_handler f2fs_xattr_trusted_handler = {
172 	.prefix	= XATTR_TRUSTED_PREFIX,
173 	.flags	= F2FS_XATTR_INDEX_TRUSTED,
174 	.list	= f2fs_xattr_trusted_list,
175 	.get	= f2fs_xattr_generic_get,
176 	.set	= f2fs_xattr_generic_set,
177 };
178 
179 const struct xattr_handler f2fs_xattr_advise_handler = {
180 	.name	= F2FS_SYSTEM_ADVISE_NAME,
181 	.flags	= F2FS_XATTR_INDEX_ADVISE,
182 	.get	= f2fs_xattr_advise_get,
183 	.set	= f2fs_xattr_advise_set,
184 };
185 
186 const struct xattr_handler f2fs_xattr_security_handler = {
187 	.prefix	= XATTR_SECURITY_PREFIX,
188 	.flags	= F2FS_XATTR_INDEX_SECURITY,
189 	.get	= f2fs_xattr_generic_get,
190 	.set	= f2fs_xattr_generic_set,
191 };
192 
193 static const struct xattr_handler * const f2fs_xattr_handler_map[] = {
194 	[F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
195 #ifdef CONFIG_F2FS_FS_POSIX_ACL
196 	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access,
197 	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
198 #endif
199 	[F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
200 #ifdef CONFIG_F2FS_FS_SECURITY
201 	[F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
202 #endif
203 	[F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
204 };
205 
206 const struct xattr_handler * const f2fs_xattr_handlers[] = {
207 	&f2fs_xattr_user_handler,
208 	&f2fs_xattr_trusted_handler,
209 #ifdef CONFIG_F2FS_FS_SECURITY
210 	&f2fs_xattr_security_handler,
211 #endif
212 	&f2fs_xattr_advise_handler,
213 	NULL,
214 };
215 
f2fs_xattr_prefix(int index,struct dentry * dentry)216 static inline const char *f2fs_xattr_prefix(int index,
217 					    struct dentry *dentry)
218 {
219 	const struct xattr_handler *handler = NULL;
220 
221 	if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
222 		handler = f2fs_xattr_handler_map[index];
223 
224 	if (!xattr_handler_can_list(handler, dentry))
225 		return NULL;
226 
227 	return xattr_prefix(handler);
228 }
229 
__find_xattr(void * base_addr,void * last_base_addr,void ** last_addr,int index,size_t len,const char * name)230 static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
231 				void *last_base_addr, void **last_addr,
232 				int index, size_t len, const char *name)
233 {
234 	struct f2fs_xattr_entry *entry;
235 
236 	list_for_each_xattr(entry, base_addr) {
237 		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
238 			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
239 			if (last_addr)
240 				*last_addr = entry;
241 			return NULL;
242 		}
243 
244 		if (entry->e_name_index != index)
245 			continue;
246 		if (entry->e_name_len != len)
247 			continue;
248 		if (!memcmp(entry->e_name, name, len))
249 			break;
250 	}
251 	return entry;
252 }
253 
__find_inline_xattr(struct inode * inode,void * base_addr,void ** last_addr,int index,size_t len,const char * name)254 static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode,
255 				void *base_addr, void **last_addr, int index,
256 				size_t len, const char *name)
257 {
258 	struct f2fs_xattr_entry *entry;
259 	unsigned int inline_size = inline_xattr_size(inode);
260 	void *max_addr = base_addr + inline_size;
261 
262 	entry = __find_xattr(base_addr, max_addr, last_addr, index, len, name);
263 	if (!entry)
264 		return NULL;
265 
266 	/* inline xattr header or entry across max inline xattr size */
267 	if (IS_XATTR_LAST_ENTRY(entry) &&
268 		(void *)entry + sizeof(__u32) > max_addr) {
269 		*last_addr = entry;
270 		return NULL;
271 	}
272 	return entry;
273 }
274 
read_inline_xattr(struct inode * inode,struct folio * ifolio,void * txattr_addr)275 static int read_inline_xattr(struct inode *inode, struct folio *ifolio,
276 							void *txattr_addr)
277 {
278 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
279 	unsigned int inline_size = inline_xattr_size(inode);
280 	struct folio *folio = NULL;
281 	void *inline_addr;
282 
283 	if (ifolio) {
284 		inline_addr = inline_xattr_addr(inode, ifolio);
285 	} else {
286 		folio = f2fs_get_inode_folio(sbi, inode->i_ino);
287 		if (IS_ERR(folio))
288 			return PTR_ERR(folio);
289 
290 		inline_addr = inline_xattr_addr(inode, folio);
291 	}
292 	memcpy(txattr_addr, inline_addr, inline_size);
293 	f2fs_folio_put(folio, true);
294 
295 	return 0;
296 }
297 
read_xattr_block(struct inode * inode,void * txattr_addr)298 static int read_xattr_block(struct inode *inode, void *txattr_addr)
299 {
300 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
301 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
302 	unsigned int inline_size = inline_xattr_size(inode);
303 	struct folio *xfolio;
304 	void *xattr_addr;
305 
306 	/* The inode already has an extended attribute block. */
307 	xfolio = f2fs_get_xnode_folio(sbi, xnid);
308 	if (IS_ERR(xfolio))
309 		return PTR_ERR(xfolio);
310 
311 	xattr_addr = folio_address(xfolio);
312 	memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE);
313 	f2fs_folio_put(xfolio, true);
314 
315 	return 0;
316 }
317 
lookup_all_xattrs(struct inode * inode,struct folio * ifolio,unsigned int index,unsigned int len,const char * name,struct f2fs_xattr_entry ** xe,void ** base_addr,int * base_size,bool * is_inline)318 static int lookup_all_xattrs(struct inode *inode, struct folio *ifolio,
319 				unsigned int index, unsigned int len,
320 				const char *name, struct f2fs_xattr_entry **xe,
321 				void **base_addr, int *base_size,
322 				bool *is_inline)
323 {
324 	void *cur_addr, *txattr_addr, *last_txattr_addr;
325 	void *last_addr = NULL;
326 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
327 	unsigned int inline_size = inline_xattr_size(inode);
328 	int err;
329 
330 	if (!xnid && !inline_size)
331 		return -ENODATA;
332 
333 	*base_size = XATTR_SIZE(inode) + XATTR_PADDING_SIZE;
334 	txattr_addr = xattr_alloc(F2FS_I_SB(inode), *base_size, is_inline);
335 	if (!txattr_addr)
336 		return -ENOMEM;
337 
338 	last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(inode);
339 
340 	/* read from inline xattr */
341 	if (inline_size) {
342 		err = read_inline_xattr(inode, ifolio, txattr_addr);
343 		if (err)
344 			goto out;
345 
346 		*xe = __find_inline_xattr(inode, txattr_addr, &last_addr,
347 						index, len, name);
348 		if (*xe) {
349 			*base_size = inline_size;
350 			goto check;
351 		}
352 	}
353 
354 	/* read from xattr node block */
355 	if (xnid) {
356 		err = read_xattr_block(inode, txattr_addr);
357 		if (err)
358 			goto out;
359 	}
360 
361 	if (last_addr)
362 		cur_addr = XATTR_HDR(last_addr) - 1;
363 	else
364 		cur_addr = txattr_addr;
365 
366 	*xe = __find_xattr(cur_addr, last_txattr_addr, NULL, index, len, name);
367 	if (!*xe) {
368 		f2fs_err(F2FS_I_SB(inode), "lookup inode (%lu) has corrupted xattr",
369 								inode->i_ino);
370 		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
371 		err = -ENODATA;
372 		f2fs_handle_error(F2FS_I_SB(inode),
373 					ERROR_CORRUPTED_XATTR);
374 		goto out;
375 	}
376 check:
377 	if (IS_XATTR_LAST_ENTRY(*xe)) {
378 		err = -ENODATA;
379 		goto out;
380 	}
381 
382 	*base_addr = txattr_addr;
383 	return 0;
384 out:
385 	xattr_free(F2FS_I_SB(inode), txattr_addr, *is_inline);
386 	return err;
387 }
388 
read_all_xattrs(struct inode * inode,struct folio * ifolio,void ** base_addr)389 static int read_all_xattrs(struct inode *inode, struct folio *ifolio,
390 							void **base_addr)
391 {
392 	struct f2fs_xattr_header *header;
393 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
394 	unsigned int size = VALID_XATTR_BLOCK_SIZE;
395 	unsigned int inline_size = inline_xattr_size(inode);
396 	void *txattr_addr;
397 	int err;
398 
399 	txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
400 			inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
401 	if (!txattr_addr)
402 		return -ENOMEM;
403 
404 	/* read from inline xattr */
405 	if (inline_size) {
406 		err = read_inline_xattr(inode, ifolio, txattr_addr);
407 		if (err)
408 			goto fail;
409 	}
410 
411 	/* read from xattr node block */
412 	if (xnid) {
413 		err = read_xattr_block(inode, txattr_addr);
414 		if (err)
415 			goto fail;
416 	}
417 
418 	header = XATTR_HDR(txattr_addr);
419 
420 	/* never been allocated xattrs */
421 	if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
422 		header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
423 		header->h_refcount = cpu_to_le32(1);
424 	}
425 	*base_addr = txattr_addr;
426 	return 0;
427 fail:
428 	kfree(txattr_addr);
429 	return err;
430 }
431 
write_all_xattrs(struct inode * inode,__u32 hsize,void * txattr_addr,struct folio * ifolio)432 static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
433 				void *txattr_addr, struct folio *ifolio)
434 {
435 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
436 	size_t inline_size = inline_xattr_size(inode);
437 	struct folio *in_folio = NULL;
438 	void *xattr_addr;
439 	void *inline_addr = NULL;
440 	struct folio *xfolio;
441 	nid_t new_nid = 0;
442 	int err = 0;
443 
444 	if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
445 		if (!f2fs_alloc_nid(sbi, &new_nid))
446 			return -ENOSPC;
447 
448 	/* write to inline xattr */
449 	if (inline_size) {
450 		if (ifolio) {
451 			inline_addr = inline_xattr_addr(inode, ifolio);
452 		} else {
453 			in_folio = f2fs_get_inode_folio(sbi, inode->i_ino);
454 			if (IS_ERR(in_folio)) {
455 				f2fs_alloc_nid_failed(sbi, new_nid);
456 				return PTR_ERR(in_folio);
457 			}
458 			inline_addr = inline_xattr_addr(inode, in_folio);
459 		}
460 
461 		f2fs_folio_wait_writeback(ifolio ? ifolio : in_folio,
462 							NODE, true, true);
463 		/* no need to use xattr node block */
464 		if (hsize <= inline_size) {
465 			err = f2fs_truncate_xattr_node(inode);
466 			f2fs_alloc_nid_failed(sbi, new_nid);
467 			if (err) {
468 				f2fs_folio_put(in_folio, true);
469 				return err;
470 			}
471 			memcpy(inline_addr, txattr_addr, inline_size);
472 			folio_mark_dirty(ifolio ? ifolio : in_folio);
473 			goto in_page_out;
474 		}
475 	}
476 
477 	/* write to xattr node block */
478 	if (F2FS_I(inode)->i_xattr_nid) {
479 		xfolio = f2fs_get_xnode_folio(sbi, F2FS_I(inode)->i_xattr_nid);
480 		if (IS_ERR(xfolio)) {
481 			err = PTR_ERR(xfolio);
482 			f2fs_alloc_nid_failed(sbi, new_nid);
483 			goto in_page_out;
484 		}
485 		f2fs_bug_on(sbi, new_nid);
486 		f2fs_folio_wait_writeback(xfolio, NODE, true, true);
487 	} else {
488 		struct dnode_of_data dn;
489 
490 		set_new_dnode(&dn, inode, NULL, NULL, new_nid);
491 		xfolio = f2fs_new_node_folio(&dn, XATTR_NODE_OFFSET);
492 		if (IS_ERR(xfolio)) {
493 			err = PTR_ERR(xfolio);
494 			f2fs_alloc_nid_failed(sbi, new_nid);
495 			goto in_page_out;
496 		}
497 		f2fs_alloc_nid_done(sbi, new_nid);
498 	}
499 	xattr_addr = folio_address(xfolio);
500 
501 	if (inline_size)
502 		memcpy(inline_addr, txattr_addr, inline_size);
503 	memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);
504 
505 	if (inline_size)
506 		folio_mark_dirty(ifolio ? ifolio : in_folio);
507 	folio_mark_dirty(xfolio);
508 
509 	f2fs_folio_put(xfolio, true);
510 in_page_out:
511 	f2fs_folio_put(in_folio, true);
512 	return err;
513 }
514 
f2fs_getxattr(struct inode * inode,int index,const char * name,void * buffer,size_t buffer_size,struct folio * ifolio)515 int f2fs_getxattr(struct inode *inode, int index, const char *name,
516 		void *buffer, size_t buffer_size, struct folio *ifolio)
517 {
518 	struct f2fs_xattr_entry *entry = NULL;
519 	int error;
520 	unsigned int size, len;
521 	void *base_addr = NULL;
522 	int base_size;
523 	bool is_inline;
524 
525 	if (name == NULL)
526 		return -EINVAL;
527 
528 	len = strlen(name);
529 	if (len > F2FS_NAME_LEN)
530 		return -ERANGE;
531 
532 	if (!ifolio)
533 		f2fs_down_read(&F2FS_I(inode)->i_xattr_sem);
534 	error = lookup_all_xattrs(inode, ifolio, index, len, name,
535 				&entry, &base_addr, &base_size, &is_inline);
536 	if (!ifolio)
537 		f2fs_up_read(&F2FS_I(inode)->i_xattr_sem);
538 	if (error)
539 		return error;
540 
541 	size = le16_to_cpu(entry->e_value_size);
542 
543 	if (buffer && size > buffer_size) {
544 		error = -ERANGE;
545 		goto out;
546 	}
547 
548 	if (buffer) {
549 		char *pval = entry->e_name + entry->e_name_len;
550 
551 		if (base_size - (pval - (char *)base_addr) < size) {
552 			error = -ERANGE;
553 			goto out;
554 		}
555 		memcpy(buffer, pval, size);
556 	}
557 	error = size;
558 out:
559 	xattr_free(F2FS_I_SB(inode), base_addr, is_inline);
560 	return error;
561 }
562 
f2fs_listxattr(struct dentry * dentry,char * buffer,size_t buffer_size)563 ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
564 {
565 	struct inode *inode = d_inode(dentry);
566 	struct f2fs_xattr_entry *entry;
567 	void *base_addr, *last_base_addr;
568 	int error;
569 	size_t rest = buffer_size;
570 
571 	f2fs_down_read(&F2FS_I(inode)->i_xattr_sem);
572 	error = read_all_xattrs(inode, NULL, &base_addr);
573 	f2fs_up_read(&F2FS_I(inode)->i_xattr_sem);
574 	if (error)
575 		return error;
576 
577 	last_base_addr = (void *)base_addr + XATTR_SIZE(inode);
578 
579 	list_for_each_xattr(entry, base_addr) {
580 		const char *prefix;
581 		size_t prefix_len;
582 		size_t size;
583 
584 		prefix = f2fs_xattr_prefix(entry->e_name_index, dentry);
585 
586 		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
587 			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
588 			f2fs_err(F2FS_I_SB(inode), "list inode (%lu) has corrupted xattr",
589 						inode->i_ino);
590 			set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
591 			f2fs_handle_error(F2FS_I_SB(inode),
592 						ERROR_CORRUPTED_XATTR);
593 			break;
594 		}
595 
596 		if (!prefix)
597 			continue;
598 
599 		prefix_len = strlen(prefix);
600 		size = prefix_len + entry->e_name_len + 1;
601 		if (buffer) {
602 			if (size > rest) {
603 				error = -ERANGE;
604 				goto cleanup;
605 			}
606 			memcpy(buffer, prefix, prefix_len);
607 			buffer += prefix_len;
608 			memcpy(buffer, entry->e_name, entry->e_name_len);
609 			buffer += entry->e_name_len;
610 			*buffer++ = 0;
611 		}
612 		rest -= size;
613 	}
614 	error = buffer_size - rest;
615 cleanup:
616 	kfree(base_addr);
617 	return error;
618 }
619 
f2fs_xattr_value_same(struct f2fs_xattr_entry * entry,const void * value,size_t size)620 static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry,
621 					const void *value, size_t size)
622 {
623 	void *pval = entry->e_name + entry->e_name_len;
624 
625 	return (le16_to_cpu(entry->e_value_size) == size) &&
626 					!memcmp(pval, value, size);
627 }
628 
__f2fs_setxattr(struct inode * inode,int index,const char * name,const void * value,size_t size,struct folio * ifolio,int flags)629 static int __f2fs_setxattr(struct inode *inode, int index,
630 			const char *name, const void *value, size_t size,
631 			struct folio *ifolio, int flags)
632 {
633 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
634 	struct f2fs_xattr_entry *here, *last;
635 	void *base_addr, *last_base_addr;
636 	int found, newsize;
637 	size_t len;
638 	__u32 new_hsize;
639 	int error;
640 
641 	if (name == NULL)
642 		return -EINVAL;
643 
644 	if (value == NULL)
645 		size = 0;
646 
647 	len = strlen(name);
648 
649 	if (len > F2FS_NAME_LEN)
650 		return -ERANGE;
651 
652 	if (size > MAX_VALUE_LEN(inode))
653 		return -E2BIG;
654 retry:
655 	error = read_all_xattrs(inode, ifolio, &base_addr);
656 	if (error)
657 		return error;
658 
659 	last_base_addr = (void *)base_addr + XATTR_SIZE(inode);
660 
661 	/* find entry with wanted name. */
662 	here = __find_xattr(base_addr, last_base_addr, NULL, index, len, name);
663 	if (!here) {
664 		if (!F2FS_I(inode)->i_xattr_nid) {
665 			error = f2fs_recover_xattr_data(inode, NULL);
666 			f2fs_notice(F2FS_I_SB(inode),
667 				"recover xattr in inode (%lu), error(%d)",
668 					inode->i_ino, error);
669 			if (!error) {
670 				kfree(base_addr);
671 				goto retry;
672 			}
673 		}
674 		f2fs_err(F2FS_I_SB(inode), "set inode (%lu) has corrupted xattr",
675 								inode->i_ino);
676 		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
677 		error = -EFSCORRUPTED;
678 		f2fs_handle_error(F2FS_I_SB(inode),
679 					ERROR_CORRUPTED_XATTR);
680 		goto exit;
681 	}
682 
683 	found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
684 
685 	if (found) {
686 		if ((flags & XATTR_CREATE)) {
687 			error = -EEXIST;
688 			goto exit;
689 		}
690 
691 		if (value && f2fs_xattr_value_same(here, value, size))
692 			goto same;
693 	} else if ((flags & XATTR_REPLACE)) {
694 		error = -ENODATA;
695 		goto exit;
696 	}
697 
698 	last = here;
699 	while (!IS_XATTR_LAST_ENTRY(last)) {
700 		if ((void *)(last) + sizeof(__u32) > last_base_addr ||
701 			(void *)XATTR_NEXT_ENTRY(last) > last_base_addr) {
702 			f2fs_err(F2FS_I_SB(inode), "inode (%lu) has invalid last xattr entry, entry_size: %zu",
703 					inode->i_ino, ENTRY_SIZE(last));
704 			set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
705 			error = -EFSCORRUPTED;
706 			f2fs_handle_error(F2FS_I_SB(inode),
707 						ERROR_CORRUPTED_XATTR);
708 			goto exit;
709 		}
710 		last = XATTR_NEXT_ENTRY(last);
711 	}
712 
713 	newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
714 
715 	/* 1. Check space */
716 	if (value) {
717 		int free;
718 		/*
719 		 * If value is NULL, it is remove operation.
720 		 * In case of update operation, we calculate free.
721 		 */
722 		free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
723 		if (found)
724 			free = free + ENTRY_SIZE(here);
725 
726 		if (unlikely(free < newsize)) {
727 			error = -E2BIG;
728 			goto exit;
729 		}
730 	}
731 
732 	/* 2. Remove old entry */
733 	if (found) {
734 		/*
735 		 * If entry is found, remove old entry.
736 		 * If not found, remove operation is not needed.
737 		 */
738 		struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
739 		int oldsize = ENTRY_SIZE(here);
740 
741 		memmove(here, next, (char *)last - (char *)next);
742 		last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
743 		memset(last, 0, oldsize);
744 	}
745 
746 	new_hsize = (char *)last - (char *)base_addr;
747 
748 	/* 3. Write new entry */
749 	if (value) {
750 		char *pval;
751 		/*
752 		 * Before we come here, old entry is removed.
753 		 * We just write new entry.
754 		 */
755 		last->e_name_index = index;
756 		last->e_name_len = len;
757 		memcpy(last->e_name, name, len);
758 		pval = last->e_name + len;
759 		memcpy(pval, value, size);
760 		last->e_value_size = cpu_to_le16(size);
761 		new_hsize += newsize;
762 		/*
763 		 * Explicitly add the null terminator.  The unused xattr space
764 		 * is supposed to always be zeroed, which would make this
765 		 * unnecessary, but don't depend on that.
766 		 */
767 		*(u32 *)((u8 *)last + newsize) = 0;
768 	}
769 
770 	error = write_all_xattrs(inode, new_hsize, base_addr, ifolio);
771 	if (error)
772 		goto exit;
773 
774 	if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
775 			!strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
776 		f2fs_set_encrypted_inode(inode);
777 
778 	if (!S_ISDIR(inode->i_mode))
779 		goto same;
780 	/*
781 	 * In restrict mode, fsync() always try to trigger checkpoint for all
782 	 * metadata consistency, in other mode, it triggers checkpoint when
783 	 * parent's xattr metadata was updated.
784 	 */
785 	if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_STRICT)
786 		set_sbi_flag(sbi, SBI_NEED_CP);
787 	else
788 		f2fs_add_ino_entry(sbi, inode->i_ino, XATTR_DIR_INO);
789 same:
790 	if (is_inode_flag_set(inode, FI_ACL_MODE)) {
791 		inode->i_mode = F2FS_I(inode)->i_acl_mode;
792 		clear_inode_flag(inode, FI_ACL_MODE);
793 	}
794 
795 	inode_set_ctime_current(inode);
796 	f2fs_mark_inode_dirty_sync(inode, true);
797 exit:
798 	kfree(base_addr);
799 	return error;
800 }
801 
f2fs_setxattr(struct inode * inode,int index,const char * name,const void * value,size_t size,struct folio * ifolio,int flags)802 int f2fs_setxattr(struct inode *inode, int index, const char *name,
803 				const void *value, size_t size,
804 				struct folio *ifolio, int flags)
805 {
806 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
807 	int err;
808 
809 	if (unlikely(f2fs_cp_error(sbi)))
810 		return -EIO;
811 	if (!f2fs_is_checkpoint_ready(sbi))
812 		return -ENOSPC;
813 
814 	err = f2fs_dquot_initialize(inode);
815 	if (err)
816 		return err;
817 
818 	/* this case is only from f2fs_init_inode_metadata */
819 	if (ifolio)
820 		return __f2fs_setxattr(inode, index, name, value,
821 						size, ifolio, flags);
822 	f2fs_balance_fs(sbi, true);
823 
824 	f2fs_lock_op(sbi);
825 	f2fs_down_write(&F2FS_I(inode)->i_xattr_sem);
826 	err = __f2fs_setxattr(inode, index, name, value, size, NULL, flags);
827 	f2fs_up_write(&F2FS_I(inode)->i_xattr_sem);
828 	f2fs_unlock_op(sbi);
829 
830 	f2fs_update_time(sbi, REQ_TIME);
831 	return err;
832 }
833 
f2fs_init_xattr_cache(void)834 int __init f2fs_init_xattr_cache(void)
835 {
836 	inline_xattr_slab = f2fs_kmem_cache_create("f2fs_xattr_entry",
837 					DEFAULT_XATTR_SLAB_SIZE);
838 	return inline_xattr_slab ? 0 : -ENOMEM;
839 }
840 
f2fs_destroy_xattr_cache(void)841 void f2fs_destroy_xattr_cache(void)
842 {
843 	kmem_cache_destroy(inline_xattr_slab);
844 }