fs/f2fs/xattr.c

   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 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
  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
  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
  67 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
  68                 struct user_namespace *mnt_userns,
  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
  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
  97 static bool f2fs_xattr_trusted_list(struct dentry *dentry)
  98 {
  99         return capable(CAP_SYS_ADMIN);
 100 }
 101
 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
 111 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
 112                 struct user_namespace *mnt_userns,
 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(&init_user_ns, 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
 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
 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] = &posix_acl_access_xattr_handler,
 196         [F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
 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 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 208         &posix_acl_access_xattr_handler,
 209         &posix_acl_default_xattr_handler,
 210 #endif
 211         &f2fs_xattr_trusted_handler,
 212 #ifdef CONFIG_F2FS_FS_SECURITY
 213         &f2fs_xattr_security_handler,
 214 #endif
 215         &f2fs_xattr_advise_handler,
 216         NULL,
 217 };
 218
 219 static inline const struct xattr_handler *f2fs_xattr_handler(int index)
 220 {
 221         const struct xattr_handler *handler = NULL;
 222
 223         if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
 224                 handler = f2fs_xattr_handler_map[index];
 225         return handler;
 226 }
 227
 228 static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
 229                                 void *last_base_addr, int index,
 230                                 size_t len, const char *name)
 231 {
 232         struct f2fs_xattr_entry *entry;
 233
 234         list_for_each_xattr(entry, base_addr) {
 235                 if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
 236                         (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr)
 237                         return NULL;
 238
 239                 if (entry->e_name_index != index)
 240                         continue;
 241                 if (entry->e_name_len != len)
 242                         continue;
 243                 if (!memcmp(entry->e_name, name, len))
 244                         break;
 245         }
 246         return entry;
 247 }
 248
 249 static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode,
 250                                 void *base_addr, void **last_addr, int index,
 251                                 size_t len, const char *name)
 252 {
 253         struct f2fs_xattr_entry *entry;
 254         unsigned int inline_size = inline_xattr_size(inode);
 255         void *max_addr = base_addr + inline_size;
 256
 257         list_for_each_xattr(entry, base_addr) {
 258                 if ((void *)entry + sizeof(__u32) > max_addr ||
 259                         (void *)XATTR_NEXT_ENTRY(entry) > max_addr) {
 260                         *last_addr = entry;
 261                         return NULL;
 262                 }
 263                 if (entry->e_name_index != index)
 264                         continue;
 265                 if (entry->e_name_len != len)
 266                         continue;
 267                 if (!memcmp(entry->e_name, name, len))
 268                         break;
 269         }
 270
 271         /* inline xattr header or entry across max inline xattr size */
 272         if (IS_XATTR_LAST_ENTRY(entry) &&
 273                 (void *)entry + sizeof(__u32) > max_addr) {
 274                 *last_addr = entry;
 275                 return NULL;
 276         }
 277         return entry;
 278 }
 279
 280 static int read_inline_xattr(struct inode *inode, struct page *ipage,
 281                                                         void *txattr_addr)
 282 {
 283         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 284         unsigned int inline_size = inline_xattr_size(inode);
 285         struct page *page = NULL;
 286         void *inline_addr;
 287
 288         if (ipage) {
 289                 inline_addr = inline_xattr_addr(inode, ipage);
 290         } else {
 291                 page = f2fs_get_node_page(sbi, inode->i_ino);
 292                 if (IS_ERR(page))
 293                         return PTR_ERR(page);
 294
 295                 inline_addr = inline_xattr_addr(inode, page);
 296         }
 297         memcpy(txattr_addr, inline_addr, inline_size);
 298         f2fs_put_page(page, 1);
 299
 300         return 0;
 301 }
 302
 303 static int read_xattr_block(struct inode *inode, void *txattr_addr)
 304 {
 305         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 306         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 307         unsigned int inline_size = inline_xattr_size(inode);
 308         struct page *xpage;
 309         void *xattr_addr;
 310
 311         /* The inode already has an extended attribute block. */
 312         xpage = f2fs_get_node_page(sbi, xnid);
 313         if (IS_ERR(xpage))
 314                 return PTR_ERR(xpage);
 315
 316         xattr_addr = page_address(xpage);
 317         memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE);
 318         f2fs_put_page(xpage, 1);
 319
 320         return 0;
 321 }
 322
 323 static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
 324                                 unsigned int index, unsigned int len,
 325                                 const char *name, struct f2fs_xattr_entry **xe,
 326                                 void **base_addr, int *base_size,
 327                                 bool *is_inline)
 328 {
 329         void *cur_addr, *txattr_addr, *last_txattr_addr;
 330         void *last_addr = NULL;
 331         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 332         unsigned int inline_size = inline_xattr_size(inode);
 333         int err;
 334
 335         if (!xnid && !inline_size)
 336                 return -ENODATA;
 337
 338         *base_size = XATTR_SIZE(inode) + XATTR_PADDING_SIZE;
 339         txattr_addr = xattr_alloc(F2FS_I_SB(inode), *base_size, is_inline);
 340         if (!txattr_addr)
 341                 return -ENOMEM;
 342
 343         last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(inode);
 344
 345         /* read from inline xattr */
 346         if (inline_size) {
 347                 err = read_inline_xattr(inode, ipage, txattr_addr);
 348                 if (err)
 349                         goto out;
 350
 351                 *xe = __find_inline_xattr(inode, txattr_addr, &last_addr,
 352                                                 index, len, name);
 353                 if (*xe) {
 354                         *base_size = inline_size;
 355                         goto check;
 356                 }
 357         }
 358
 359         /* read from xattr node block */
 360         if (xnid) {
 361                 err = read_xattr_block(inode, txattr_addr);
 362                 if (err)
 363                         goto out;
 364         }
 365
 366         if (last_addr)
 367                 cur_addr = XATTR_HDR(last_addr) - 1;
 368         else
 369                 cur_addr = txattr_addr;
 370
 371         *xe = __find_xattr(cur_addr, last_txattr_addr, index, len, name);
 372         if (!*xe) {
 373                 f2fs_err(F2FS_I_SB(inode), "inode (%lu) has corrupted xattr",
 374                                                                 inode->i_ino);
 375                 set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
 376                 err = -EFSCORRUPTED;
 377                 goto out;
 378         }
 379 check:
 380         if (IS_XATTR_LAST_ENTRY(*xe)) {
 381                 err = -ENODATA;
 382                 goto out;
 383         }
 384
 385         *base_addr = txattr_addr;
 386         return 0;
 387 out:
 388         xattr_free(F2FS_I_SB(inode), txattr_addr, *is_inline);
 389         return err;
 390 }
 391
 392 static int read_all_xattrs(struct inode *inode, struct page *ipage,
 393                                                         void **base_addr)
 394 {
 395         struct f2fs_xattr_header *header;
 396         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 397         unsigned int size = VALID_XATTR_BLOCK_SIZE;
 398         unsigned int inline_size = inline_xattr_size(inode);
 399         void *txattr_addr;
 400         int err;
 401
 402         txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
 403                         inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
 404         if (!txattr_addr)
 405                 return -ENOMEM;
 406
 407         /* read from inline xattr */
 408         if (inline_size) {
 409                 err = read_inline_xattr(inode, ipage, txattr_addr);
 410                 if (err)
 411                         goto fail;
 412         }
 413
 414         /* read from xattr node block */
 415         if (xnid) {
 416                 err = read_xattr_block(inode, txattr_addr);
 417                 if (err)
 418                         goto fail;
 419         }
 420
 421         header = XATTR_HDR(txattr_addr);
 422
 423         /* never been allocated xattrs */
 424         if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
 425                 header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
 426                 header->h_refcount = cpu_to_le32(1);
 427         }
 428         *base_addr = txattr_addr;
 429         return 0;
 430 fail:
 431         kfree(txattr_addr);
 432         return err;
 433 }
 434
 435 static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
 436                                 void *txattr_addr, struct page *ipage)
 437 {
 438         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 439         size_t inline_size = inline_xattr_size(inode);
 440         struct page *in_page = NULL;
 441         void *xattr_addr;
 442         void *inline_addr = NULL;
 443         struct page *xpage;
 444         nid_t new_nid = 0;
 445         int err = 0;
 446
 447         if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
 448                 if (!f2fs_alloc_nid(sbi, &new_nid))
 449                         return -ENOSPC;
 450
 451         /* write to inline xattr */
 452         if (inline_size) {
 453                 if (ipage) {
 454                         inline_addr = inline_xattr_addr(inode, ipage);
 455                 } else {
 456                         in_page = f2fs_get_node_page(sbi, inode->i_ino);
 457                         if (IS_ERR(in_page)) {
 458                                 f2fs_alloc_nid_failed(sbi, new_nid);
 459                                 return PTR_ERR(in_page);
 460                         }
 461                         inline_addr = inline_xattr_addr(inode, in_page);
 462                 }
 463
 464                 f2fs_wait_on_page_writeback(ipage ? ipage : in_page,
 465                                                         NODE, true, true);
 466                 /* no need to use xattr node block */
 467                 if (hsize <= inline_size) {
 468                         err = f2fs_truncate_xattr_node(inode);
 469                         f2fs_alloc_nid_failed(sbi, new_nid);
 470                         if (err) {
 471                                 f2fs_put_page(in_page, 1);
 472                                 return err;
 473                         }
 474                         memcpy(inline_addr, txattr_addr, inline_size);
 475                         set_page_dirty(ipage ? ipage : in_page);
 476                         goto in_page_out;
 477                 }
 478         }
 479
 480         /* write to xattr node block */
 481         if (F2FS_I(inode)->i_xattr_nid) {
 482                 xpage = f2fs_get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
 483                 if (IS_ERR(xpage)) {
 484                         err = PTR_ERR(xpage);
 485                         f2fs_alloc_nid_failed(sbi, new_nid);
 486                         goto in_page_out;
 487                 }
 488                 f2fs_bug_on(sbi, new_nid);
 489                 f2fs_wait_on_page_writeback(xpage, NODE, true, true);
 490         } else {
 491                 struct dnode_of_data dn;
 492
 493                 set_new_dnode(&dn, inode, NULL, NULL, new_nid);
 494                 xpage = f2fs_new_node_page(&dn, XATTR_NODE_OFFSET);
 495                 if (IS_ERR(xpage)) {
 496                         err = PTR_ERR(xpage);
 497                         f2fs_alloc_nid_failed(sbi, new_nid);
 498                         goto in_page_out;
 499                 }
 500                 f2fs_alloc_nid_done(sbi, new_nid);
 501         }
 502         xattr_addr = page_address(xpage);
 503
 504         if (inline_size)
 505                 memcpy(inline_addr, txattr_addr, inline_size);
 506         memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);
 507
 508         if (inline_size)
 509                 set_page_dirty(ipage ? ipage : in_page);
 510         set_page_dirty(xpage);
 511
 512         f2fs_put_page(xpage, 1);
 513 in_page_out:
 514         f2fs_put_page(in_page, 1);
 515         return err;
 516 }
 517
 518 int f2fs_getxattr(struct inode *inode, int index, const char *name,
 519                 void *buffer, size_t buffer_size, struct page *ipage)
 520 {
 521         struct f2fs_xattr_entry *entry = NULL;
 522         int error;
 523         unsigned int size, len;
 524         void *base_addr = NULL;
 525         int base_size;
 526         bool is_inline;
 527
 528         if (name == NULL)
 529                 return -EINVAL;
 530
 531         len = strlen(name);
 532         if (len > F2FS_NAME_LEN)
 533                 return -ERANGE;
 534
 535         down_read(&F2FS_I(inode)->i_xattr_sem);
 536         error = lookup_all_xattrs(inode, ipage, index, len, name,
 537                                 &entry, &base_addr, &base_size, &is_inline);
 538         up_read(&F2FS_I(inode)->i_xattr_sem);
 539         if (error)
 540                 return error;
 541
 542         size = le16_to_cpu(entry->e_value_size);
 543
 544         if (buffer && size > buffer_size) {
 545                 error = -ERANGE;
 546                 goto out;
 547         }
 548
 549         if (buffer) {
 550                 char *pval = entry->e_name + entry->e_name_len;
 551
 552                 if (base_size - (pval - (char *)base_addr) < size) {
 553                         error = -ERANGE;
 554                         goto out;
 555                 }
 556                 memcpy(buffer, pval, size);
 557         }
 558         error = size;
 559 out:
 560         xattr_free(F2FS_I_SB(inode), base_addr, is_inline);
 561         return error;
 562 }
 563
 564 ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
 565 {
 566         struct inode *inode = d_inode(dentry);
 567         struct f2fs_xattr_entry *entry;
 568         void *base_addr, *last_base_addr;
 569         int error;
 570         size_t rest = buffer_size;
 571
 572         down_read(&F2FS_I(inode)->i_xattr_sem);
 573         error = read_all_xattrs(inode, NULL, &base_addr);
 574         up_read(&F2FS_I(inode)->i_xattr_sem);
 575         if (error)
 576                 return error;
 577
 578         last_base_addr = (void *)base_addr + XATTR_SIZE(inode);
 579
 580         list_for_each_xattr(entry, base_addr) {
 581                 const struct xattr_handler *handler =
 582                         f2fs_xattr_handler(entry->e_name_index);
 583                 const char *prefix;
 584                 size_t prefix_len;
 585                 size_t size;
 586
 587                 if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
 588                         (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
 589                         f2fs_err(F2FS_I_SB(inode), "inode (%lu) has corrupted xattr",
 590                                                 inode->i_ino);
 591                         set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
 592                         error = -EFSCORRUPTED;
 593                         goto cleanup;
 594                 }
 595
 596                 if (!handler || (handler->list && !handler->list(dentry)))
 597                         continue;
 598
 599                 prefix = xattr_prefix(handler);
 600                 prefix_len = strlen(prefix);
 601                 size = prefix_len + entry->e_name_len + 1;
 602                 if (buffer) {
 603                         if (size > rest) {
 604                                 error = -ERANGE;
 605                                 goto cleanup;
 606                         }
 607                         memcpy(buffer, prefix, prefix_len);
 608                         buffer += prefix_len;
 609                         memcpy(buffer, entry->e_name, entry->e_name_len);
 610                         buffer += entry->e_name_len;
 611                         *buffer++ = 0;
 612                 }
 613                 rest -= size;
 614         }
 615         error = buffer_size - rest;
 616 cleanup:
 617         kfree(base_addr);
 618         return error;
 619 }
 620
 621 static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry,
 622                                         const void *value, size_t size)
 623 {
 624         void *pval = entry->e_name + entry->e_name_len;
 625
 626         return (le16_to_cpu(entry->e_value_size) == size) &&
 627                                         !memcmp(pval, value, size);
 628 }
 629
 630 static int __f2fs_setxattr(struct inode *inode, int index,
 631                         const char *name, const void *value, size_t size,
 632                         struct page *ipage, int flags)
 633 {
 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
 655         error = read_all_xattrs(inode, ipage, &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, index, len, name);
 663         if (!here) {
 664                 f2fs_err(F2FS_I_SB(inode), "inode (%lu) has corrupted xattr",
 665                                                                 inode->i_ino);
 666                 set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
 667                 error = -EFSCORRUPTED;
 668                 goto exit;
 669         }
 670
 671         found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
 672
 673         if (found) {
 674                 if ((flags & XATTR_CREATE)) {
 675                         error = -EEXIST;
 676                         goto exit;
 677                 }
 678
 679                 if (value && f2fs_xattr_value_same(here, value, size))
 680                         goto same;
 681         } else if ((flags & XATTR_REPLACE)) {
 682                 error = -ENODATA;
 683                 goto exit;
 684         }
 685
 686         last = here;
 687         while (!IS_XATTR_LAST_ENTRY(last))
 688                 last = XATTR_NEXT_ENTRY(last);
 689
 690         newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
 691
 692         /* 1. Check space */
 693         if (value) {
 694                 int free;
 695                 /*
 696                  * If value is NULL, it is remove operation.
 697                  * In case of update operation, we calculate free.
 698                  */
 699                 free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
 700                 if (found)
 701                         free = free + ENTRY_SIZE(here);
 702
 703                 if (unlikely(free < newsize)) {
 704                         error = -E2BIG;
 705                         goto exit;
 706                 }
 707         }
 708
 709         /* 2. Remove old entry */
 710         if (found) {
 711                 /*
 712                  * If entry is found, remove old entry.
 713                  * If not found, remove operation is not needed.
 714                  */
 715                 struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
 716                 int oldsize = ENTRY_SIZE(here);
 717
 718                 memmove(here, next, (char *)last - (char *)next);
 719                 last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
 720                 memset(last, 0, oldsize);
 721         }
 722
 723         new_hsize = (char *)last - (char *)base_addr;
 724
 725         /* 3. Write new entry */
 726         if (value) {
 727                 char *pval;
 728                 /*
 729                  * Before we come here, old entry is removed.
 730                  * We just write new entry.
 731                  */
 732                 last->e_name_index = index;
 733                 last->e_name_len = len;
 734                 memcpy(last->e_name, name, len);
 735                 pval = last->e_name + len;
 736                 memcpy(pval, value, size);
 737                 last->e_value_size = cpu_to_le16(size);
 738                 new_hsize += newsize;
 739         }
 740
 741         error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
 742         if (error)
 743                 goto exit;
 744
 745         if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
 746                         !strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
 747                 f2fs_set_encrypted_inode(inode);
 748         f2fs_mark_inode_dirty_sync(inode, true);
 749         if (!error && S_ISDIR(inode->i_mode))
 750                 set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_CP);
 751
 752 same:
 753         if (is_inode_flag_set(inode, FI_ACL_MODE)) {
 754                 inode->i_mode = F2FS_I(inode)->i_acl_mode;
 755                 inode->i_ctime = current_time(inode);
 756                 clear_inode_flag(inode, FI_ACL_MODE);
 757         }
 758
 759 exit:
 760         kfree(base_addr);
 761         return error;
 762 }
 763
 764 int f2fs_setxattr(struct inode *inode, int index, const char *name,
 765                                 const void *value, size_t size,
 766                                 struct page *ipage, int flags)
 767 {
 768         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 769         int err;
 770
 771         if (unlikely(f2fs_cp_error(sbi)))
 772                 return -EIO;
 773         if (!f2fs_is_checkpoint_ready(sbi))
 774                 return -ENOSPC;
 775
 776         err = dquot_initialize(inode);
 777         if (err)
 778                 return err;
 779
 780         /* this case is only from f2fs_init_inode_metadata */
 781         if (ipage)
 782                 return __f2fs_setxattr(inode, index, name, value,
 783                                                 size, ipage, flags);
 784         f2fs_balance_fs(sbi, true);
 785
 786         f2fs_lock_op(sbi);
 787         down_write(&F2FS_I(inode)->i_xattr_sem);
 788         err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
 789         up_write(&F2FS_I(inode)->i_xattr_sem);
 790         f2fs_unlock_op(sbi);
 791
 792         f2fs_update_time(sbi, REQ_TIME);
 793         return err;
 794 }
 795
 796 int f2fs_init_xattr_caches(struct f2fs_sb_info *sbi)
 797 {
 798         dev_t dev = sbi->sb->s_bdev->bd_dev;
 799         char slab_name[32];
 800
 801         sprintf(slab_name, "f2fs_xattr_entry-%u:%u", MAJOR(dev), MINOR(dev));
 802
 803         sbi->inline_xattr_slab_size = F2FS_OPTION(sbi).inline_xattr_size *
 804                                         sizeof(__le32) + XATTR_PADDING_SIZE;
 805
 806         sbi->inline_xattr_slab = f2fs_kmem_cache_create(slab_name,
 807                                         sbi->inline_xattr_slab_size);
 808         if (!sbi->inline_xattr_slab)
 809                 return -ENOMEM;
 810
 811         return 0;
 812 }
 813
 814 void f2fs_destroy_xattr_caches(struct f2fs_sb_info *sbi)
 815 {
 816         kmem_cache_destroy(sbi->inline_xattr_slab);
 817 }