xref: /openbmc/linux/fs/f2fs/xattr.c (revision 6c59f87e)
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 
xattr_alloc(struct f2fs_sb_info * sbi,int size,bool * is_inline)26 static void *xattr_alloc(struct f2fs_sb_info *sbi, int size, bool *is_inline)
27 {
28 	if (likely(size == sbi->inline_xattr_slab_size)) {
29 		*is_inline = true;
30 		return f2fs_kmem_cache_alloc(sbi->inline_xattr_slab,
31 					GFP_F2FS_ZERO, false, sbi);
32 	}
33 	*is_inline = false;
34 	return f2fs_kzalloc(sbi, size, GFP_NOFS);
35 }
36 
xattr_free(struct f2fs_sb_info * sbi,void * xattr_addr,bool is_inline)37 static void xattr_free(struct f2fs_sb_info *sbi, void *xattr_addr,
38 							bool is_inline)
39 {
40 	if (is_inline)
41 		kmem_cache_free(sbi->inline_xattr_slab, xattr_addr);
42 	else
43 		kfree(xattr_addr);
44 }
45 
f2fs_xattr_generic_get(const struct xattr_handler * handler,struct dentry * unused,struct inode * inode,const char * name,void * buffer,size_t size)46 static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
47 		struct dentry *unused, struct inode *inode,
48 		const char *name, void *buffer, size_t size)
49 {
50 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
51 
52 	switch (handler->flags) {
53 	case F2FS_XATTR_INDEX_USER:
54 		if (!test_opt(sbi, XATTR_USER))
55 			return -EOPNOTSUPP;
56 		break;
57 	case F2FS_XATTR_INDEX_TRUSTED:
58 	case F2FS_XATTR_INDEX_SECURITY:
59 		break;
60 	default:
61 		return -EINVAL;
62 	}
63 	return f2fs_getxattr(inode, handler->flags, name,
64 			     buffer, size, NULL);
65 }
66 
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)67 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
68 		struct mnt_idmap *idmap,
69 		struct dentry *unused, struct inode *inode,
70 		const char *name, const void *value,
71 		size_t size, int flags)
72 {
73 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
74 
75 	switch (handler->flags) {
76 	case F2FS_XATTR_INDEX_USER:
77 		if (!test_opt(sbi, XATTR_USER))
78 			return -EOPNOTSUPP;
79 		break;
80 	case F2FS_XATTR_INDEX_TRUSTED:
81 	case F2FS_XATTR_INDEX_SECURITY:
82 		break;
83 	default:
84 		return -EINVAL;
85 	}
86 	return f2fs_setxattr(inode, handler->flags, name,
87 					value, size, NULL, flags);
88 }
89 
f2fs_xattr_user_list(struct dentry * dentry)90 static bool f2fs_xattr_user_list(struct dentry *dentry)
91 {
92 	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
93 
94 	return test_opt(sbi, XATTR_USER);
95 }
96 
f2fs_xattr_trusted_list(struct dentry * dentry)97 static bool f2fs_xattr_trusted_list(struct dentry *dentry)
98 {
99 	return capable(CAP_SYS_ADMIN);
100 }
101 
f2fs_xattr_advise_get(const struct xattr_handler * handler,struct dentry * unused,struct inode * inode,const char * name,void * buffer,size_t size)102 static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
103 		struct dentry *unused, struct inode *inode,
104 		const char *name, void *buffer, size_t size)
105 {
106 	if (buffer)
107 		*((char *)buffer) = F2FS_I(inode)->i_advise;
108 	return sizeof(char);
109 }
110 
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)111 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
112 		struct mnt_idmap *idmap,
113 		struct dentry *unused, struct inode *inode,
114 		const char *name, const void *value,
115 		size_t size, int flags)
116 {
117 	unsigned char old_advise = F2FS_I(inode)->i_advise;
118 	unsigned char new_advise;
119 
120 	if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
121 		return -EPERM;
122 	if (value == NULL)
123 		return -EINVAL;
124 
125 	new_advise = *(char *)value;
126 	if (new_advise & ~FADVISE_MODIFIABLE_BITS)
127 		return -EINVAL;
128 
129 	new_advise = new_advise & FADVISE_MODIFIABLE_BITS;
130 	new_advise |= old_advise & ~FADVISE_MODIFIABLE_BITS;
131 
132 	F2FS_I(inode)->i_advise = new_advise;
133 	f2fs_mark_inode_dirty_sync(inode, true);
134 	return 0;
135 }
136 
137 #ifdef CONFIG_F2FS_FS_SECURITY
f2fs_initxattrs(struct inode * inode,const struct xattr * xattr_array,void * page)138 static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
139 		void *page)
140 {
141 	const struct xattr *xattr;
142 	int err = 0;
143 
144 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
145 		err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
146 				xattr->name, xattr->value,
147 				xattr->value_len, (struct page *)page, 0);
148 		if (err < 0)
149 			break;
150 	}
151 	return err;
152 }
153 
f2fs_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,struct page * ipage)154 int f2fs_init_security(struct inode *inode, struct inode *dir,
155 				const struct qstr *qstr, struct page *ipage)
156 {
157 	return security_inode_init_security(inode, dir, qstr,
158 				&f2fs_initxattrs, ipage);
159 }
160 #endif
161 
162 const struct xattr_handler f2fs_xattr_user_handler = {
163 	.prefix	= XATTR_USER_PREFIX,
164 	.flags	= F2FS_XATTR_INDEX_USER,
165 	.list	= f2fs_xattr_user_list,
166 	.get	= f2fs_xattr_generic_get,
167 	.set	= f2fs_xattr_generic_set,
168 };
169 
170 const struct xattr_handler f2fs_xattr_trusted_handler = {
171 	.prefix	= XATTR_TRUSTED_PREFIX,
172 	.flags	= F2FS_XATTR_INDEX_TRUSTED,
173 	.list	= f2fs_xattr_trusted_list,
174 	.get	= f2fs_xattr_generic_get,
175 	.set	= f2fs_xattr_generic_set,
176 };
177 
178 const struct xattr_handler f2fs_xattr_advise_handler = {
179 	.name	= F2FS_SYSTEM_ADVISE_NAME,
180 	.flags	= F2FS_XATTR_INDEX_ADVISE,
181 	.get	= f2fs_xattr_advise_get,
182 	.set	= f2fs_xattr_advise_set,
183 };
184 
185 const struct xattr_handler f2fs_xattr_security_handler = {
186 	.prefix	= XATTR_SECURITY_PREFIX,
187 	.flags	= F2FS_XATTR_INDEX_SECURITY,
188 	.get	= f2fs_xattr_generic_get,
189 	.set	= f2fs_xattr_generic_set,
190 };
191 
192 static const struct xattr_handler *f2fs_xattr_handler_map[] = {
193 	[F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
194 #ifdef CONFIG_F2FS_FS_POSIX_ACL
195 	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access,
196 	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
197 #endif
198 	[F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
199 #ifdef CONFIG_F2FS_FS_SECURITY
200 	[F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
201 #endif
202 	[F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
203 };
204 
205 const struct xattr_handler *f2fs_xattr_handlers[] = {
206 	&f2fs_xattr_user_handler,
207 	&f2fs_xattr_trusted_handler,
208 #ifdef CONFIG_F2FS_FS_SECURITY
209 	&f2fs_xattr_security_handler,
210 #endif
211 	&f2fs_xattr_advise_handler,
212 	NULL,
213 };
214 
f2fs_xattr_prefix(int index,struct dentry * dentry)215 static inline const char *f2fs_xattr_prefix(int index,
216 					    struct dentry *dentry)
217 {
218 	const struct xattr_handler *handler = NULL;
219 
220 	if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
221 		handler = f2fs_xattr_handler_map[index];
222 
223 	if (!xattr_handler_can_list(handler, dentry))
224 		return NULL;
225 
226 	return xattr_prefix(handler);
227 }
228 
__find_xattr(void * base_addr,void * last_base_addr,void ** last_addr,int index,size_t len,const char * name)229 static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
230 				void *last_base_addr, void **last_addr,
231 				int index, size_t len, const char *name)
232 {
233 	struct f2fs_xattr_entry *entry;
234 
235 	list_for_each_xattr(entry, base_addr) {
236 		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
237 			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
238 			if (last_addr)
239 				*last_addr = entry;
240 			return NULL;
241 		}
242 
243 		if (entry->e_name_index != index)
244 			continue;
245 		if (entry->e_name_len != len)
246 			continue;
247 		if (!memcmp(entry->e_name, name, len))
248 			break;
249 	}
250 	return entry;
251 }
252 
__find_inline_xattr(struct inode * inode,void * base_addr,void ** last_addr,int index,size_t len,const char * name)253 static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode,
254 				void *base_addr, void **last_addr, int index,
255 				size_t len, const char *name)
256 {
257 	struct f2fs_xattr_entry *entry;
258 	unsigned int inline_size = inline_xattr_size(inode);
259 	void *max_addr = base_addr + inline_size;
260 
261 	entry = __find_xattr(base_addr, max_addr, last_addr, index, len, name);
262 	if (!entry)
263 		return NULL;
264 
265 	/* inline xattr header or entry across max inline xattr size */
266 	if (IS_XATTR_LAST_ENTRY(entry) &&
267 		(void *)entry + sizeof(__u32) > max_addr) {
268 		*last_addr = entry;
269 		return NULL;
270 	}
271 	return entry;
272 }
273 
read_inline_xattr(struct inode * inode,struct page * ipage,void * txattr_addr)274 static int read_inline_xattr(struct inode *inode, struct page *ipage,
275 							void *txattr_addr)
276 {
277 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
278 	unsigned int inline_size = inline_xattr_size(inode);
279 	struct page *page = NULL;
280 	void *inline_addr;
281 
282 	if (ipage) {
283 		inline_addr = inline_xattr_addr(inode, ipage);
284 	} else {
285 		page = f2fs_get_node_page(sbi, inode->i_ino);
286 		if (IS_ERR(page))
287 			return PTR_ERR(page);
288 
289 		inline_addr = inline_xattr_addr(inode, page);
290 	}
291 	memcpy(txattr_addr, inline_addr, inline_size);
292 	f2fs_put_page(page, 1);
293 
294 	return 0;
295 }
296 
read_xattr_block(struct inode * inode,void * txattr_addr)297 static int read_xattr_block(struct inode *inode, void *txattr_addr)
298 {
299 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
300 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
301 	unsigned int inline_size = inline_xattr_size(inode);
302 	struct page *xpage;
303 	void *xattr_addr;
304 
305 	/* The inode already has an extended attribute block. */
306 	xpage = f2fs_get_node_page(sbi, xnid);
307 	if (IS_ERR(xpage))
308 		return PTR_ERR(xpage);
309 
310 	xattr_addr = page_address(xpage);
311 	memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE);
312 	f2fs_put_page(xpage, 1);
313 
314 	return 0;
315 }
316 
lookup_all_xattrs(struct inode * inode,struct page * ipage,unsigned int index,unsigned int len,const char * name,struct f2fs_xattr_entry ** xe,void ** base_addr,int * base_size,bool * is_inline)317 static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
318 				unsigned int index, unsigned int len,
319 				const char *name, struct f2fs_xattr_entry **xe,
320 				void **base_addr, int *base_size,
321 				bool *is_inline)
322 {
323 	void *cur_addr, *txattr_addr, *last_txattr_addr;
324 	void *last_addr = NULL;
325 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
326 	unsigned int inline_size = inline_xattr_size(inode);
327 	int err;
328 
329 	if (!xnid && !inline_size)
330 		return -ENODATA;
331 
332 	*base_size = XATTR_SIZE(inode) + XATTR_PADDING_SIZE;
333 	txattr_addr = xattr_alloc(F2FS_I_SB(inode), *base_size, is_inline);
334 	if (!txattr_addr)
335 		return -ENOMEM;
336 
337 	last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(inode);
338 
339 	/* read from inline xattr */
340 	if (inline_size) {
341 		err = read_inline_xattr(inode, ipage, txattr_addr);
342 		if (err)
343 			goto out;
344 
345 		*xe = __find_inline_xattr(inode, txattr_addr, &last_addr,
346 						index, len, name);
347 		if (*xe) {
348 			*base_size = inline_size;
349 			goto check;
350 		}
351 	}
352 
353 	/* read from xattr node block */
354 	if (xnid) {
355 		err = read_xattr_block(inode, txattr_addr);
356 		if (err)
357 			goto out;
358 	}
359 
360 	if (last_addr)
361 		cur_addr = XATTR_HDR(last_addr) - 1;
362 	else
363 		cur_addr = txattr_addr;
364 
365 	*xe = __find_xattr(cur_addr, last_txattr_addr, NULL, index, len, name);
366 	if (!*xe) {
367 		f2fs_err(F2FS_I_SB(inode), "lookup inode (%lu) has corrupted xattr",
368 								inode->i_ino);
369 		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
370 		err = -ENODATA;
371 		f2fs_handle_error(F2FS_I_SB(inode),
372 					ERROR_CORRUPTED_XATTR);
373 		goto out;
374 	}
375 check:
376 	if (IS_XATTR_LAST_ENTRY(*xe)) {
377 		err = -ENODATA;
378 		goto out;
379 	}
380 
381 	*base_addr = txattr_addr;
382 	return 0;
383 out:
384 	xattr_free(F2FS_I_SB(inode), txattr_addr, *is_inline);
385 	return err;
386 }
387 
read_all_xattrs(struct inode * inode,struct page * ipage,void ** base_addr)388 static int read_all_xattrs(struct inode *inode, struct page *ipage,
389 							void **base_addr)
390 {
391 	struct f2fs_xattr_header *header;
392 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
393 	unsigned int size = VALID_XATTR_BLOCK_SIZE;
394 	unsigned int inline_size = inline_xattr_size(inode);
395 	void *txattr_addr;
396 	int err;
397 
398 	txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
399 			inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
400 	if (!txattr_addr)
401 		return -ENOMEM;
402 
403 	/* read from inline xattr */
404 	if (inline_size) {
405 		err = read_inline_xattr(inode, ipage, txattr_addr);
406 		if (err)
407 			goto fail;
408 	}
409 
410 	/* read from xattr node block */
411 	if (xnid) {
412 		err = read_xattr_block(inode, txattr_addr);
413 		if (err)
414 			goto fail;
415 	}
416 
417 	header = XATTR_HDR(txattr_addr);
418 
419 	/* never been allocated xattrs */
420 	if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
421 		header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
422 		header->h_refcount = cpu_to_le32(1);
423 	}
424 	*base_addr = txattr_addr;
425 	return 0;
426 fail:
427 	kfree(txattr_addr);
428 	return err;
429 }
430 
write_all_xattrs(struct inode * inode,__u32 hsize,void * txattr_addr,struct page * ipage)431 static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
432 				void *txattr_addr, struct page *ipage)
433 {
434 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
435 	size_t inline_size = inline_xattr_size(inode);
436 	struct page *in_page = NULL;
437 	void *xattr_addr;
438 	void *inline_addr = NULL;
439 	struct page *xpage;
440 	nid_t new_nid = 0;
441 	int err = 0;
442 
443 	if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
444 		if (!f2fs_alloc_nid(sbi, &new_nid))
445 			return -ENOSPC;
446 
447 	/* write to inline xattr */
448 	if (inline_size) {
449 		if (ipage) {
450 			inline_addr = inline_xattr_addr(inode, ipage);
451 		} else {
452 			in_page = f2fs_get_node_page(sbi, inode->i_ino);
453 			if (IS_ERR(in_page)) {
454 				f2fs_alloc_nid_failed(sbi, new_nid);
455 				return PTR_ERR(in_page);
456 			}
457 			inline_addr = inline_xattr_addr(inode, in_page);
458 		}
459 
460 		f2fs_wait_on_page_writeback(ipage ? ipage : in_page,
461 							NODE, true, true);
462 		/* no need to use xattr node block */
463 		if (hsize <= inline_size) {
464 			err = f2fs_truncate_xattr_node(inode);
465 			f2fs_alloc_nid_failed(sbi, new_nid);
466 			if (err) {
467 				f2fs_put_page(in_page, 1);
468 				return err;
469 			}
470 			memcpy(inline_addr, txattr_addr, inline_size);
471 			set_page_dirty(ipage ? ipage : in_page);
472 			goto in_page_out;
473 		}
474 	}
475 
476 	/* write to xattr node block */
477 	if (F2FS_I(inode)->i_xattr_nid) {
478 		xpage = f2fs_get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
479 		if (IS_ERR(xpage)) {
480 			err = PTR_ERR(xpage);
481 			f2fs_alloc_nid_failed(sbi, new_nid);
482 			goto in_page_out;
483 		}
484 		f2fs_bug_on(sbi, new_nid);
485 		f2fs_wait_on_page_writeback(xpage, NODE, true, true);
486 	} else {
487 		struct dnode_of_data dn;
488 
489 		set_new_dnode(&dn, inode, NULL, NULL, new_nid);
490 		xpage = f2fs_new_node_page(&dn, XATTR_NODE_OFFSET);
491 		if (IS_ERR(xpage)) {
492 			err = PTR_ERR(xpage);
493 			f2fs_alloc_nid_failed(sbi, new_nid);
494 			goto in_page_out;
495 		}
496 		f2fs_alloc_nid_done(sbi, new_nid);
497 	}
498 	xattr_addr = page_address(xpage);
499 
500 	if (inline_size)
501 		memcpy(inline_addr, txattr_addr, inline_size);
502 	memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);
503 
504 	if (inline_size)
505 		set_page_dirty(ipage ? ipage : in_page);
506 	set_page_dirty(xpage);
507 
508 	f2fs_put_page(xpage, 1);
509 in_page_out:
510 	f2fs_put_page(in_page, 1);
511 	return err;
512 }
513 
f2fs_getxattr(struct inode * inode,int index,const char * name,void * buffer,size_t buffer_size,struct page * ipage)514 int f2fs_getxattr(struct inode *inode, int index, const char *name,
515 		void *buffer, size_t buffer_size, struct page *ipage)
516 {
517 	struct f2fs_xattr_entry *entry = NULL;
518 	int error;
519 	unsigned int size, len;
520 	void *base_addr = NULL;
521 	int base_size;
522 	bool is_inline;
523 
524 	if (name == NULL)
525 		return -EINVAL;
526 
527 	len = strlen(name);
528 	if (len > F2FS_NAME_LEN)
529 		return -ERANGE;
530 
531 	if (!ipage)
532 		f2fs_down_read(&F2FS_I(inode)->i_xattr_sem);
533 	error = lookup_all_xattrs(inode, ipage, index, len, name,
534 				&entry, &base_addr, &base_size, &is_inline);
535 	if (!ipage)
536 		f2fs_up_read(&F2FS_I(inode)->i_xattr_sem);
537 	if (error)
538 		return error;
539 
540 	size = le16_to_cpu(entry->e_value_size);
541 
542 	if (buffer && size > buffer_size) {
543 		error = -ERANGE;
544 		goto out;
545 	}
546 
547 	if (buffer) {
548 		char *pval = entry->e_name + entry->e_name_len;
549 
550 		if (base_size - (pval - (char *)base_addr) < size) {
551 			error = -ERANGE;
552 			goto out;
553 		}
554 		memcpy(buffer, pval, size);
555 	}
556 	error = size;
557 out:
558 	xattr_free(F2FS_I_SB(inode), base_addr, is_inline);
559 	return error;
560 }
561 
f2fs_listxattr(struct dentry * dentry,char * buffer,size_t buffer_size)562 ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
563 {
564 	struct inode *inode = d_inode(dentry);
565 	struct f2fs_xattr_entry *entry;
566 	void *base_addr, *last_base_addr;
567 	int error;
568 	size_t rest = buffer_size;
569 
570 	f2fs_down_read(&F2FS_I(inode)->i_xattr_sem);
571 	error = read_all_xattrs(inode, NULL, &base_addr);
572 	f2fs_up_read(&F2FS_I(inode)->i_xattr_sem);
573 	if (error)
574 		return error;
575 
576 	last_base_addr = (void *)base_addr + XATTR_SIZE(inode);
577 
578 	list_for_each_xattr(entry, base_addr) {
579 		const char *prefix;
580 		size_t prefix_len;
581 		size_t size;
582 
583 		prefix = f2fs_xattr_prefix(entry->e_name_index, dentry);
584 
585 		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
586 			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
587 			f2fs_err(F2FS_I_SB(inode), "list inode (%lu) has corrupted xattr",
588 						inode->i_ino);
589 			set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
590 			f2fs_handle_error(F2FS_I_SB(inode),
591 						ERROR_CORRUPTED_XATTR);
592 			break;
593 		}
594 
595 		if (!prefix)
596 			continue;
597 
598 		prefix_len = strlen(prefix);
599 		size = prefix_len + entry->e_name_len + 1;
600 		if (buffer) {
601 			if (size > rest) {
602 				error = -ERANGE;
603 				goto cleanup;
604 			}
605 			memcpy(buffer, prefix, prefix_len);
606 			buffer += prefix_len;
607 			memcpy(buffer, entry->e_name, entry->e_name_len);
608 			buffer += entry->e_name_len;
609 			*buffer++ = 0;
610 		}
611 		rest -= size;
612 	}
613 	error = buffer_size - rest;
614 cleanup:
615 	kfree(base_addr);
616 	return error;
617 }
618 
f2fs_xattr_value_same(struct f2fs_xattr_entry * entry,const void * value,size_t size)619 static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry,
620 					const void *value, size_t size)
621 {
622 	void *pval = entry->e_name + entry->e_name_len;
623 
624 	return (le16_to_cpu(entry->e_value_size) == size) &&
625 					!memcmp(pval, value, size);
626 }
627 
__f2fs_setxattr(struct inode * inode,int index,const char * name,const void * value,size_t size,struct page * ipage,int flags)628 static int __f2fs_setxattr(struct inode *inode, int index,
629 			const char *name, const void *value, size_t size,
630 			struct page *ipage, int flags)
631 {
632 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
633 	struct f2fs_xattr_entry *here, *last;
634 	void *base_addr, *last_base_addr;
635 	int found, newsize;
636 	size_t len;
637 	__u32 new_hsize;
638 	int error;
639 
640 	if (name == NULL)
641 		return -EINVAL;
642 
643 	if (value == NULL)
644 		size = 0;
645 
646 	len = strlen(name);
647 
648 	if (len > F2FS_NAME_LEN)
649 		return -ERANGE;
650 
651 	if (size > MAX_VALUE_LEN(inode))
652 		return -E2BIG;
653 retry:
654 	error = read_all_xattrs(inode, ipage, &base_addr);
655 	if (error)
656 		return error;
657 
658 	last_base_addr = (void *)base_addr + XATTR_SIZE(inode);
659 
660 	/* find entry with wanted name. */
661 	here = __find_xattr(base_addr, last_base_addr, NULL, index, len, name);
662 	if (!here) {
663 		if (!F2FS_I(inode)->i_xattr_nid) {
664 			error = f2fs_recover_xattr_data(inode, NULL);
665 			f2fs_notice(F2FS_I_SB(inode),
666 				"recover xattr in inode (%lu), error(%d)",
667 					inode->i_ino, error);
668 			if (!error) {
669 				kfree(base_addr);
670 				goto retry;
671 			}
672 		}
673 		f2fs_err(F2FS_I_SB(inode), "set inode (%lu) has corrupted xattr",
674 								inode->i_ino);
675 		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
676 		error = -EFSCORRUPTED;
677 		f2fs_handle_error(F2FS_I_SB(inode),
678 					ERROR_CORRUPTED_XATTR);
679 		goto exit;
680 	}
681 
682 	found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
683 
684 	if (found) {
685 		if ((flags & XATTR_CREATE)) {
686 			error = -EEXIST;
687 			goto exit;
688 		}
689 
690 		if (value && f2fs_xattr_value_same(here, value, size))
691 			goto same;
692 	} else if ((flags & XATTR_REPLACE)) {
693 		error = -ENODATA;
694 		goto exit;
695 	}
696 
697 	last = here;
698 	while (!IS_XATTR_LAST_ENTRY(last)) {
699 		if ((void *)(last) + sizeof(__u32) > last_base_addr ||
700 			(void *)XATTR_NEXT_ENTRY(last) > last_base_addr) {
701 			f2fs_err(F2FS_I_SB(inode), "inode (%lu) has invalid last xattr entry, entry_size: %zu",
702 					inode->i_ino, ENTRY_SIZE(last));
703 			set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
704 			error = -EFSCORRUPTED;
705 			f2fs_handle_error(F2FS_I_SB(inode),
706 						ERROR_CORRUPTED_XATTR);
707 			goto exit;
708 		}
709 		last = XATTR_NEXT_ENTRY(last);
710 	}
711 
712 	newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
713 
714 	/* 1. Check space */
715 	if (value) {
716 		int free;
717 		/*
718 		 * If value is NULL, it is remove operation.
719 		 * In case of update operation, we calculate free.
720 		 */
721 		free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
722 		if (found)
723 			free = free + ENTRY_SIZE(here);
724 
725 		if (unlikely(free < newsize)) {
726 			error = -E2BIG;
727 			goto exit;
728 		}
729 	}
730 
731 	/* 2. Remove old entry */
732 	if (found) {
733 		/*
734 		 * If entry is found, remove old entry.
735 		 * If not found, remove operation is not needed.
736 		 */
737 		struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
738 		int oldsize = ENTRY_SIZE(here);
739 
740 		memmove(here, next, (char *)last - (char *)next);
741 		last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
742 		memset(last, 0, oldsize);
743 	}
744 
745 	new_hsize = (char *)last - (char *)base_addr;
746 
747 	/* 3. Write new entry */
748 	if (value) {
749 		char *pval;
750 		/*
751 		 * Before we come here, old entry is removed.
752 		 * We just write new entry.
753 		 */
754 		last->e_name_index = index;
755 		last->e_name_len = len;
756 		memcpy(last->e_name, name, len);
757 		pval = last->e_name + len;
758 		memcpy(pval, value, size);
759 		last->e_value_size = cpu_to_le16(size);
760 		new_hsize += newsize;
761 		/*
762 		 * Explicitly add the null terminator.  The unused xattr space
763 		 * is supposed to always be zeroed, which would make this
764 		 * unnecessary, but don't depend on that.
765 		 */
766 		*(u32 *)((u8 *)last + newsize) = 0;
767 	}
768 
769 	error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
770 	if (error)
771 		goto exit;
772 
773 	if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
774 			!strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
775 		f2fs_set_encrypted_inode(inode);
776 
777 	if (!S_ISDIR(inode->i_mode))
778 		goto same;
779 	/*
780 	 * In restrict mode, fsync() always try to trigger checkpoint for all
781 	 * metadata consistency, in other mode, it triggers checkpoint when
782 	 * parent's xattr metadata was updated.
783 	 */
784 	if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_STRICT)
785 		set_sbi_flag(sbi, SBI_NEED_CP);
786 	else
787 		f2fs_add_ino_entry(sbi, inode->i_ino, XATTR_DIR_INO);
788 same:
789 	if (is_inode_flag_set(inode, FI_ACL_MODE)) {
790 		inode->i_mode = F2FS_I(inode)->i_acl_mode;
791 		clear_inode_flag(inode, FI_ACL_MODE);
792 	}
793 
794 	inode_set_ctime_current(inode);
795 	f2fs_mark_inode_dirty_sync(inode, true);
796 exit:
797 	kfree(base_addr);
798 	return error;
799 }
800 
f2fs_setxattr(struct inode * inode,int index,const char * name,const void * value,size_t size,struct page * ipage,int flags)801 int f2fs_setxattr(struct inode *inode, int index, const char *name,
802 				const void *value, size_t size,
803 				struct page *ipage, int flags)
804 {
805 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
806 	int err;
807 
808 	if (unlikely(f2fs_cp_error(sbi)))
809 		return -EIO;
810 	if (!f2fs_is_checkpoint_ready(sbi))
811 		return -ENOSPC;
812 
813 	err = f2fs_dquot_initialize(inode);
814 	if (err)
815 		return err;
816 
817 	/* this case is only from f2fs_init_inode_metadata */
818 	if (ipage)
819 		return __f2fs_setxattr(inode, index, name, value,
820 						size, ipage, flags);
821 	f2fs_balance_fs(sbi, true);
822 
823 	f2fs_lock_op(sbi);
824 	f2fs_down_write(&F2FS_I(inode)->i_xattr_sem);
825 	err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
826 	f2fs_up_write(&F2FS_I(inode)->i_xattr_sem);
827 	f2fs_unlock_op(sbi);
828 
829 	f2fs_update_time(sbi, REQ_TIME);
830 	return err;
831 }
832 
f2fs_init_xattr_caches(struct f2fs_sb_info * sbi)833 int f2fs_init_xattr_caches(struct f2fs_sb_info *sbi)
834 {
835 	dev_t dev = sbi->sb->s_bdev->bd_dev;
836 	char slab_name[32];
837 
838 	sprintf(slab_name, "f2fs_xattr_entry-%u:%u", MAJOR(dev), MINOR(dev));
839 
840 	sbi->inline_xattr_slab_size = F2FS_OPTION(sbi).inline_xattr_size *
841 					sizeof(__le32) + XATTR_PADDING_SIZE;
842 
843 	sbi->inline_xattr_slab = f2fs_kmem_cache_create(slab_name,
844 					sbi->inline_xattr_slab_size);
845 	if (!sbi->inline_xattr_slab)
846 		return -ENOMEM;
847 
848 	return 0;
849 }
850 
f2fs_destroy_xattr_caches(struct f2fs_sb_info * sbi)851 void f2fs_destroy_xattr_caches(struct f2fs_sb_info *sbi)
852 {
853 	kmem_cache_destroy(sbi->inline_xattr_slab);
854 }
855