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1 /*
2  * fs/f2fs/xattr.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * Portions of this code from linux/fs/ext2/xattr.c
8  *
9  * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
10  *
11  * Fix by Harrison Xing <harrison@mountainviewdata.com>.
12  * Extended attributes for symlinks and special files added per
13  *  suggestion of Luka Renko <luka.renko@hermes.si>.
14  * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
15  *  Red Hat Inc.
16  *
17  * This program is free software; you can redistribute it and/or modify
18  * it under the terms of the GNU General Public License version 2 as
19  * published by the Free Software Foundation.
20  */
21 #include <linux/rwsem.h>
22 #include <linux/f2fs_fs.h>
23 #include <linux/security.h>
24 #include <linux/posix_acl_xattr.h>
25 #include "f2fs.h"
26 #include "xattr.h"
27 
f2fs_xattr_generic_list(const struct xattr_handler * handler,struct dentry * dentry,char * list,size_t list_size,const char * name,size_t len)28 static size_t f2fs_xattr_generic_list(const struct xattr_handler *handler,
29 		struct dentry *dentry, char *list, size_t list_size,
30 		const char *name, size_t len)
31 {
32 	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
33 	int total_len, prefix_len;
34 
35 	switch (handler->flags) {
36 	case F2FS_XATTR_INDEX_USER:
37 		if (!test_opt(sbi, XATTR_USER))
38 			return -EOPNOTSUPP;
39 		break;
40 	case F2FS_XATTR_INDEX_TRUSTED:
41 		if (!capable(CAP_SYS_ADMIN))
42 			return -EPERM;
43 		break;
44 	case F2FS_XATTR_INDEX_SECURITY:
45 		break;
46 	default:
47 		return -EINVAL;
48 	}
49 
50 	prefix_len = strlen(handler->prefix);
51 	total_len = prefix_len + len + 1;
52 	if (list && total_len <= list_size) {
53 		memcpy(list, handler->prefix, prefix_len);
54 		memcpy(list + prefix_len, name, len);
55 		list[prefix_len + len] = '\0';
56 	}
57 	return total_len;
58 }
59 
f2fs_xattr_generic_get(const struct xattr_handler * handler,struct dentry * dentry,const char * name,void * buffer,size_t size)60 static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
61 		struct dentry *dentry, const char *name, void *buffer,
62 		size_t size)
63 {
64 	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
65 
66 	switch (handler->flags) {
67 	case F2FS_XATTR_INDEX_USER:
68 		if (!test_opt(sbi, XATTR_USER))
69 			return -EOPNOTSUPP;
70 		break;
71 	case F2FS_XATTR_INDEX_TRUSTED:
72 		if (!capable(CAP_SYS_ADMIN))
73 			return -EPERM;
74 		break;
75 	case F2FS_XATTR_INDEX_SECURITY:
76 		break;
77 	default:
78 		return -EINVAL;
79 	}
80 	if (strcmp(name, "") == 0)
81 		return -EINVAL;
82 	return f2fs_getxattr(d_inode(dentry), handler->flags, name,
83 			     buffer, size, NULL);
84 }
85 
f2fs_xattr_generic_set(const struct xattr_handler * handler,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)86 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
87 		struct dentry *dentry, const char *name, const void *value,
88 		size_t size, int flags)
89 {
90 	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
91 
92 	switch (handler->flags) {
93 	case F2FS_XATTR_INDEX_USER:
94 		if (!test_opt(sbi, XATTR_USER))
95 			return -EOPNOTSUPP;
96 		break;
97 	case F2FS_XATTR_INDEX_TRUSTED:
98 		if (!capable(CAP_SYS_ADMIN))
99 			return -EPERM;
100 		break;
101 	case F2FS_XATTR_INDEX_SECURITY:
102 		break;
103 	default:
104 		return -EINVAL;
105 	}
106 	if (strcmp(name, "") == 0)
107 		return -EINVAL;
108 
109 	return f2fs_setxattr(d_inode(dentry), handler->flags, name,
110 					value, size, NULL, flags);
111 }
112 
f2fs_xattr_advise_list(const struct xattr_handler * handler,struct dentry * dentry,char * list,size_t list_size,const char * name,size_t len)113 static size_t f2fs_xattr_advise_list(const struct xattr_handler *handler,
114 		struct dentry *dentry, char *list, size_t list_size,
115 		const char *name, size_t len)
116 {
117 	const char *xname = F2FS_SYSTEM_ADVISE_PREFIX;
118 	size_t size;
119 
120 	size = strlen(xname) + 1;
121 	if (list && size <= list_size)
122 		memcpy(list, xname, size);
123 	return size;
124 }
125 
f2fs_xattr_advise_get(const struct xattr_handler * handler,struct dentry * dentry,const char * name,void * buffer,size_t size)126 static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
127 		struct dentry *dentry, const char *name, void *buffer,
128 		size_t size)
129 {
130 	struct inode *inode = d_inode(dentry);
131 
132 	if (strcmp(name, "") != 0)
133 		return -EINVAL;
134 
135 	if (buffer)
136 		*((char *)buffer) = F2FS_I(inode)->i_advise;
137 	return sizeof(char);
138 }
139 
f2fs_xattr_advise_set(const struct xattr_handler * handler,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)140 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
141 		struct dentry *dentry, const char *name, const void *value,
142 		size_t size, int flags)
143 {
144 	struct inode *inode = d_inode(dentry);
145 
146 	if (strcmp(name, "") != 0)
147 		return -EINVAL;
148 	if (!inode_owner_or_capable(inode))
149 		return -EPERM;
150 	if (value == NULL)
151 		return -EINVAL;
152 
153 	F2FS_I(inode)->i_advise |= *(char *)value;
154 	f2fs_mark_inode_dirty_sync(inode, true);
155 	return 0;
156 }
157 
158 #ifdef CONFIG_F2FS_FS_SECURITY
f2fs_initxattrs(struct inode * inode,const struct xattr * xattr_array,void * page)159 static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
160 		void *page)
161 {
162 	const struct xattr *xattr;
163 	int err = 0;
164 
165 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
166 		err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
167 				xattr->name, xattr->value,
168 				xattr->value_len, (struct page *)page, 0);
169 		if (err < 0)
170 			break;
171 	}
172 	return err;
173 }
174 
f2fs_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,struct page * ipage)175 int f2fs_init_security(struct inode *inode, struct inode *dir,
176 				const struct qstr *qstr, struct page *ipage)
177 {
178 	return security_inode_init_security(inode, dir, qstr,
179 				&f2fs_initxattrs, ipage);
180 }
181 #endif
182 
183 const struct xattr_handler f2fs_xattr_user_handler = {
184 	.prefix	= XATTR_USER_PREFIX,
185 	.flags	= F2FS_XATTR_INDEX_USER,
186 	.list	= f2fs_xattr_generic_list,
187 	.get	= f2fs_xattr_generic_get,
188 	.set	= f2fs_xattr_generic_set,
189 };
190 
191 const struct xattr_handler f2fs_xattr_trusted_handler = {
192 	.prefix	= XATTR_TRUSTED_PREFIX,
193 	.flags	= F2FS_XATTR_INDEX_TRUSTED,
194 	.list	= f2fs_xattr_generic_list,
195 	.get	= f2fs_xattr_generic_get,
196 	.set	= f2fs_xattr_generic_set,
197 };
198 
199 const struct xattr_handler f2fs_xattr_advise_handler = {
200 	.prefix = F2FS_SYSTEM_ADVISE_PREFIX,
201 	.flags	= F2FS_XATTR_INDEX_ADVISE,
202 	.list   = f2fs_xattr_advise_list,
203 	.get    = f2fs_xattr_advise_get,
204 	.set    = f2fs_xattr_advise_set,
205 };
206 
207 const struct xattr_handler f2fs_xattr_security_handler = {
208 	.prefix	= XATTR_SECURITY_PREFIX,
209 	.flags	= F2FS_XATTR_INDEX_SECURITY,
210 	.list	= f2fs_xattr_generic_list,
211 	.get	= f2fs_xattr_generic_get,
212 	.set	= f2fs_xattr_generic_set,
213 };
214 
215 static const struct xattr_handler *f2fs_xattr_handler_map[] = {
216 	[F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
217 #ifdef CONFIG_F2FS_FS_POSIX_ACL
218 	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
219 	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
220 #endif
221 	[F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
222 #ifdef CONFIG_F2FS_FS_SECURITY
223 	[F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
224 #endif
225 	[F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
226 };
227 
228 const struct xattr_handler *f2fs_xattr_handlers[] = {
229 	&f2fs_xattr_user_handler,
230 #ifdef CONFIG_F2FS_FS_POSIX_ACL
231 	&posix_acl_access_xattr_handler,
232 	&posix_acl_default_xattr_handler,
233 #endif
234 	&f2fs_xattr_trusted_handler,
235 #ifdef CONFIG_F2FS_FS_SECURITY
236 	&f2fs_xattr_security_handler,
237 #endif
238 	&f2fs_xattr_advise_handler,
239 	NULL,
240 };
241 
f2fs_xattr_handler(int index)242 static inline const struct xattr_handler *f2fs_xattr_handler(int index)
243 {
244 	const struct xattr_handler *handler = NULL;
245 
246 	if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
247 		handler = f2fs_xattr_handler_map[index];
248 	return handler;
249 }
250 
__find_xattr(void * base_addr,int index,size_t len,const char * name)251 static struct f2fs_xattr_entry *__find_xattr(void *base_addr, int index,
252 					size_t len, const char *name)
253 {
254 	struct f2fs_xattr_entry *entry;
255 
256 	list_for_each_xattr(entry, base_addr) {
257 		if (entry->e_name_index != index)
258 			continue;
259 		if (entry->e_name_len != len)
260 			continue;
261 		if (!memcmp(entry->e_name, name, len))
262 			break;
263 	}
264 	return entry;
265 }
266 
__find_inline_xattr(struct inode * inode,void * base_addr,void ** last_addr,int index,size_t len,const char * name)267 static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode,
268 				void *base_addr, void **last_addr, int index,
269 				size_t len, const char *name)
270 {
271 	struct f2fs_xattr_entry *entry;
272 	unsigned int inline_size = inline_xattr_size(inode);
273 
274 	list_for_each_xattr(entry, base_addr) {
275 		if ((void *)entry + sizeof(__u32) > base_addr + inline_size ||
276 			(void *)XATTR_NEXT_ENTRY(entry) + sizeof(__u32) >
277 			base_addr + inline_size) {
278 			*last_addr = entry;
279 			return NULL;
280 		}
281 		if (entry->e_name_index != index)
282 			continue;
283 		if (entry->e_name_len != len)
284 			continue;
285 		if (!memcmp(entry->e_name, name, len))
286 			break;
287 	}
288 	return entry;
289 }
290 
read_inline_xattr(struct inode * inode,struct page * ipage,void * txattr_addr)291 static int read_inline_xattr(struct inode *inode, struct page *ipage,
292 							void *txattr_addr)
293 {
294 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
295 	unsigned int inline_size = inline_xattr_size(inode);
296 	struct page *page = NULL;
297 	void *inline_addr;
298 
299 	if (ipage) {
300 		inline_addr = inline_xattr_addr(inode, ipage);
301 	} else {
302 		page = get_node_page(sbi, inode->i_ino);
303 		if (IS_ERR(page))
304 			return PTR_ERR(page);
305 
306 		inline_addr = inline_xattr_addr(inode, page);
307 	}
308 	memcpy(txattr_addr, inline_addr, inline_size);
309 	f2fs_put_page(page, 1);
310 
311 	return 0;
312 }
313 
read_xattr_block(struct inode * inode,void * txattr_addr)314 static int read_xattr_block(struct inode *inode, void *txattr_addr)
315 {
316 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
317 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
318 	unsigned int inline_size = inline_xattr_size(inode);
319 	struct page *xpage;
320 	void *xattr_addr;
321 
322 	/* The inode already has an extended attribute block. */
323 	xpage = get_node_page(sbi, xnid);
324 	if (IS_ERR(xpage))
325 		return PTR_ERR(xpage);
326 
327 	xattr_addr = page_address(xpage);
328 	memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE);
329 	f2fs_put_page(xpage, 1);
330 
331 	return 0;
332 }
333 
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)334 static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
335 				unsigned int index, unsigned int len,
336 				const char *name, struct f2fs_xattr_entry **xe,
337 				void **base_addr)
338 {
339 	void *cur_addr, *txattr_addr, *last_addr = NULL;
340 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
341 	unsigned int size = xnid ? VALID_XATTR_BLOCK_SIZE : 0;
342 	unsigned int inline_size = inline_xattr_size(inode);
343 	int err = 0;
344 
345 	if (!size && !inline_size)
346 		return -ENODATA;
347 
348 	txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
349 			inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
350 	if (!txattr_addr)
351 		return -ENOMEM;
352 
353 	/* read from inline xattr */
354 	if (inline_size) {
355 		err = read_inline_xattr(inode, ipage, txattr_addr);
356 		if (err)
357 			goto out;
358 
359 		*xe = __find_inline_xattr(inode, txattr_addr, &last_addr,
360 						index, len, name);
361 		if (*xe)
362 			goto check;
363 	}
364 
365 	/* read from xattr node block */
366 	if (xnid) {
367 		err = read_xattr_block(inode, txattr_addr);
368 		if (err)
369 			goto out;
370 	}
371 
372 	if (last_addr)
373 		cur_addr = XATTR_HDR(last_addr) - 1;
374 	else
375 		cur_addr = txattr_addr;
376 
377 	*xe = __find_xattr(cur_addr, index, len, name);
378 check:
379 	if (IS_XATTR_LAST_ENTRY(*xe)) {
380 		err = -ENODATA;
381 		goto out;
382 	}
383 
384 	*base_addr = txattr_addr;
385 	return 0;
386 out:
387 	kzfree(txattr_addr);
388 	return err;
389 }
390 
read_all_xattrs(struct inode * inode,struct page * ipage,void ** base_addr)391 static int read_all_xattrs(struct inode *inode, struct page *ipage,
392 							void **base_addr)
393 {
394 	struct f2fs_xattr_header *header;
395 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
396 	unsigned int size = VALID_XATTR_BLOCK_SIZE;
397 	unsigned int inline_size = inline_xattr_size(inode);
398 	void *txattr_addr;
399 	int err;
400 
401 	txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
402 			inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
403 	if (!txattr_addr)
404 		return -ENOMEM;
405 
406 	/* read from inline xattr */
407 	if (inline_size) {
408 		err = read_inline_xattr(inode, ipage, txattr_addr);
409 		if (err)
410 			goto fail;
411 	}
412 
413 	/* read from xattr node block */
414 	if (xnid) {
415 		err = read_xattr_block(inode, txattr_addr);
416 		if (err)
417 			goto fail;
418 	}
419 
420 	header = XATTR_HDR(txattr_addr);
421 
422 	/* never been allocated xattrs */
423 	if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
424 		header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
425 		header->h_refcount = cpu_to_le32(1);
426 	}
427 	*base_addr = txattr_addr;
428 	return 0;
429 fail:
430 	kzfree(txattr_addr);
431 	return err;
432 }
433 
write_all_xattrs(struct inode * inode,__u32 hsize,void * txattr_addr,struct page * ipage)434 static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
435 				void *txattr_addr, struct page *ipage)
436 {
437 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
438 	size_t inline_size = inline_xattr_size(inode);
439 	struct page *in_page = NULL;
440 	void *xattr_addr;
441 	void *inline_addr = NULL;
442 	struct page *xpage;
443 	nid_t new_nid = 0;
444 	int err = 0;
445 
446 	if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
447 		if (!alloc_nid(sbi, &new_nid))
448 			return -ENOSPC;
449 
450 	/* write to inline xattr */
451 	if (inline_size) {
452 		if (ipage) {
453 			inline_addr = inline_xattr_addr(inode, ipage);
454 		} else {
455 			in_page = get_node_page(sbi, inode->i_ino);
456 			if (IS_ERR(in_page)) {
457 				alloc_nid_failed(sbi, new_nid);
458 				return PTR_ERR(in_page);
459 			}
460 			inline_addr = inline_xattr_addr(inode, in_page);
461 		}
462 
463 		f2fs_wait_on_page_writeback(ipage ? ipage : in_page,
464 							NODE, true);
465 		/* no need to use xattr node block */
466 		if (hsize <= inline_size) {
467 			err = truncate_xattr_node(inode);
468 			alloc_nid_failed(sbi, new_nid);
469 			if (err) {
470 				f2fs_put_page(in_page, 1);
471 				return err;
472 			}
473 			memcpy(inline_addr, txattr_addr, inline_size);
474 			set_page_dirty(ipage ? ipage : in_page);
475 			goto in_page_out;
476 		}
477 	}
478 
479 	/* write to xattr node block */
480 	if (F2FS_I(inode)->i_xattr_nid) {
481 		xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
482 		if (IS_ERR(xpage)) {
483 			err = PTR_ERR(xpage);
484 			alloc_nid_failed(sbi, new_nid);
485 			goto in_page_out;
486 		}
487 		f2fs_bug_on(sbi, new_nid);
488 		f2fs_wait_on_page_writeback(xpage, NODE, true);
489 	} else {
490 		struct dnode_of_data dn;
491 		set_new_dnode(&dn, inode, NULL, NULL, new_nid);
492 		xpage = new_node_page(&dn, XATTR_NODE_OFFSET);
493 		if (IS_ERR(xpage)) {
494 			err = PTR_ERR(xpage);
495 			alloc_nid_failed(sbi, new_nid);
496 			goto in_page_out;
497 		}
498 		alloc_nid_done(sbi, new_nid);
499 	}
500 	xattr_addr = page_address(xpage);
501 
502 	if (inline_size)
503 		memcpy(inline_addr, txattr_addr, inline_size);
504 	memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);
505 
506 	if (inline_size)
507 		set_page_dirty(ipage ? ipage : in_page);
508 	set_page_dirty(xpage);
509 
510 	f2fs_put_page(xpage, 1);
511 in_page_out:
512 	f2fs_put_page(in_page, 1);
513 	return err;
514 }
515 
f2fs_getxattr(struct inode * inode,int index,const char * name,void * buffer,size_t buffer_size,struct page * ipage)516 int f2fs_getxattr(struct inode *inode, int index, const char *name,
517 		void *buffer, size_t buffer_size, struct page *ipage)
518 {
519 	struct f2fs_xattr_entry *entry = NULL;
520 	int error = 0;
521 	unsigned int size, len;
522 	void *base_addr = NULL;
523 
524 	if (name == NULL)
525 		return -EINVAL;
526 
527 	len = strlen(name);
528 	if (len > F2FS_NAME_LEN)
529 		return -ERANGE;
530 
531 	down_read(&F2FS_I(inode)->i_xattr_sem);
532 	error = lookup_all_xattrs(inode, ipage, index, len, name,
533 				&entry, &base_addr);
534 	up_read(&F2FS_I(inode)->i_xattr_sem);
535 	if (error)
536 		return error;
537 
538 	size = le16_to_cpu(entry->e_value_size);
539 
540 	if (buffer && size > buffer_size) {
541 		error = -ERANGE;
542 		goto out;
543 	}
544 
545 	if (buffer) {
546 		char *pval = entry->e_name + entry->e_name_len;
547 		memcpy(buffer, pval, size);
548 	}
549 	error = size;
550 out:
551 	kzfree(base_addr);
552 	return error;
553 }
554 
f2fs_listxattr(struct dentry * dentry,char * buffer,size_t buffer_size)555 ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
556 {
557 	struct inode *inode = d_inode(dentry);
558 	struct f2fs_xattr_entry *entry;
559 	void *base_addr;
560 	int error = 0;
561 	size_t rest = buffer_size;
562 
563 	down_read(&F2FS_I(inode)->i_xattr_sem);
564 	error = read_all_xattrs(inode, NULL, &base_addr);
565 	up_read(&F2FS_I(inode)->i_xattr_sem);
566 	if (error)
567 		return error;
568 
569 	list_for_each_xattr(entry, base_addr) {
570 		const struct xattr_handler *handler =
571 			f2fs_xattr_handler(entry->e_name_index);
572 		size_t size;
573 
574 		if (!handler)
575 			continue;
576 
577 		size = handler->list(handler, dentry, buffer, rest,
578 				     entry->e_name, entry->e_name_len);
579 		if (buffer && size > rest) {
580 			error = -ERANGE;
581 			goto cleanup;
582 		}
583 
584 		if (buffer)
585 			buffer += size;
586 		rest -= size;
587 	}
588 	error = buffer_size - rest;
589 cleanup:
590 	kzfree(base_addr);
591 	return error;
592 }
593 
f2fs_xattr_value_same(struct f2fs_xattr_entry * entry,const void * value,size_t size)594 static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry,
595 					const void *value, size_t size)
596 {
597 	void *pval = entry->e_name + entry->e_name_len;
598 
599 	return (le16_to_cpu(entry->e_value_size) == size) &&
600 					!memcmp(pval, value, size);
601 }
602 
__f2fs_setxattr(struct inode * inode,int index,const char * name,const void * value,size_t size,struct page * ipage,int flags)603 static int __f2fs_setxattr(struct inode *inode, int index,
604 			const char *name, const void *value, size_t size,
605 			struct page *ipage, int flags)
606 {
607 	struct f2fs_xattr_entry *here, *last;
608 	void *base_addr;
609 	int found, newsize;
610 	size_t len;
611 	__u32 new_hsize;
612 	int error = 0;
613 
614 	if (name == NULL)
615 		return -EINVAL;
616 
617 	if (value == NULL)
618 		size = 0;
619 
620 	len = strlen(name);
621 
622 	if (len > F2FS_NAME_LEN)
623 		return -ERANGE;
624 
625 	if (size > MAX_VALUE_LEN(inode))
626 		return -E2BIG;
627 
628 	error = read_all_xattrs(inode, ipage, &base_addr);
629 	if (error)
630 		return error;
631 
632 	/* find entry with wanted name. */
633 	here = __find_xattr(base_addr, index, len, name);
634 
635 	found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
636 
637 	if (found) {
638 		if ((flags & XATTR_CREATE)) {
639 			error = -EEXIST;
640 			goto exit;
641 		}
642 
643 		if (value && f2fs_xattr_value_same(here, value, size))
644 			goto exit;
645 	} else if ((flags & XATTR_REPLACE)) {
646 		error = -ENODATA;
647 		goto exit;
648 	}
649 
650 	last = here;
651 	while (!IS_XATTR_LAST_ENTRY(last))
652 		last = XATTR_NEXT_ENTRY(last);
653 
654 	newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
655 
656 	/* 1. Check space */
657 	if (value) {
658 		int free;
659 		/*
660 		 * If value is NULL, it is remove operation.
661 		 * In case of update operation, we calculate free.
662 		 */
663 		free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
664 		if (found)
665 			free = free + ENTRY_SIZE(here);
666 
667 		if (unlikely(free < newsize)) {
668 			error = -E2BIG;
669 			goto exit;
670 		}
671 	}
672 
673 	/* 2. Remove old entry */
674 	if (found) {
675 		/*
676 		 * If entry is found, remove old entry.
677 		 * If not found, remove operation is not needed.
678 		 */
679 		struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
680 		int oldsize = ENTRY_SIZE(here);
681 
682 		memmove(here, next, (char *)last - (char *)next);
683 		last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
684 		memset(last, 0, oldsize);
685 	}
686 
687 	new_hsize = (char *)last - (char *)base_addr;
688 
689 	/* 3. Write new entry */
690 	if (value) {
691 		char *pval;
692 		/*
693 		 * Before we come here, old entry is removed.
694 		 * We just write new entry.
695 		 */
696 		last->e_name_index = index;
697 		last->e_name_len = len;
698 		memcpy(last->e_name, name, len);
699 		pval = last->e_name + len;
700 		memcpy(pval, value, size);
701 		last->e_value_size = cpu_to_le16(size);
702 		new_hsize += newsize;
703 	}
704 
705 	error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
706 	if (error)
707 		goto exit;
708 
709 	if (is_inode_flag_set(inode, FI_ACL_MODE)) {
710 		inode->i_mode = F2FS_I(inode)->i_acl_mode;
711 		inode->i_ctime = current_time(inode);
712 		clear_inode_flag(inode, FI_ACL_MODE);
713 	}
714 	if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
715 			!strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
716 		f2fs_set_encrypted_inode(inode);
717 	f2fs_mark_inode_dirty_sync(inode, true);
718 	if (!error && S_ISDIR(inode->i_mode))
719 		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_CP);
720 exit:
721 	kzfree(base_addr);
722 	return error;
723 }
724 
f2fs_setxattr(struct inode * inode,int index,const char * name,const void * value,size_t size,struct page * ipage,int flags)725 int f2fs_setxattr(struct inode *inode, int index, const char *name,
726 				const void *value, size_t size,
727 				struct page *ipage, int flags)
728 {
729 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
730 	int err;
731 
732 	err = dquot_initialize(inode);
733 	if (err)
734 		return err;
735 
736 	/* this case is only from init_inode_metadata */
737 	if (ipage)
738 		return __f2fs_setxattr(inode, index, name, value,
739 						size, ipage, flags);
740 	f2fs_balance_fs(sbi, true);
741 
742 	f2fs_lock_op(sbi);
743 	/* protect xattr_ver */
744 	down_write(&F2FS_I(inode)->i_sem);
745 	down_write(&F2FS_I(inode)->i_xattr_sem);
746 	err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
747 	up_write(&F2FS_I(inode)->i_xattr_sem);
748 	up_write(&F2FS_I(inode)->i_sem);
749 	f2fs_unlock_op(sbi);
750 
751 	f2fs_update_time(sbi, REQ_TIME);
752 	return err;
753 }
754