1 /* 2 * Copyright (C) International Business Machines Corp., 2000-2004 3 * Copyright (C) Christoph Hellwig, 2002 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 13 * the GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #include <linux/capability.h> 21 #include <linux/fs.h> 22 #include <linux/xattr.h> 23 #include <linux/posix_acl_xattr.h> 24 #include <linux/slab.h> 25 #include <linux/quotaops.h> 26 #include <linux/security.h> 27 #include "jfs_incore.h" 28 #include "jfs_superblock.h" 29 #include "jfs_dmap.h" 30 #include "jfs_debug.h" 31 #include "jfs_dinode.h" 32 #include "jfs_extent.h" 33 #include "jfs_metapage.h" 34 #include "jfs_xattr.h" 35 #include "jfs_acl.h" 36 37 /* 38 * jfs_xattr.c: extended attribute service 39 * 40 * Overall design -- 41 * 42 * Format: 43 * 44 * Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit 45 * value) and a variable (0 or more) number of extended attribute 46 * entries. Each extended attribute entry (jfs_ea) is a <name,value> double 47 * where <name> is constructed from a null-terminated ascii string 48 * (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data 49 * (1 ... 65535 bytes). The in-memory format is 50 * 51 * 0 1 2 4 4 + namelen + 1 52 * +-------+--------+--------+----------------+-------------------+ 53 * | Flags | Name | Value | Name String \0 | Data . . . . | 54 * | | Length | Length | | | 55 * +-------+--------+--------+----------------+-------------------+ 56 * 57 * A jfs_ea_list then is structured as 58 * 59 * 0 4 4 + EA_SIZE(ea1) 60 * +------------+-------------------+--------------------+----- 61 * | Overall EA | First FEA Element | Second FEA Element | ..... 62 * | List Size | | | 63 * +------------+-------------------+--------------------+----- 64 * 65 * On-disk: 66 * 67 * FEALISTs are stored on disk using blocks allocated by dbAlloc() and 68 * written directly. An EA list may be in-lined in the inode if there is 69 * sufficient room available. 70 */ 71 72 struct ea_buffer { 73 int flag; /* Indicates what storage xattr points to */ 74 int max_size; /* largest xattr that fits in current buffer */ 75 dxd_t new_ea; /* dxd to replace ea when modifying xattr */ 76 struct metapage *mp; /* metapage containing ea list */ 77 struct jfs_ea_list *xattr; /* buffer containing ea list */ 78 }; 79 80 /* 81 * ea_buffer.flag values 82 */ 83 #define EA_INLINE 0x0001 84 #define EA_EXTENT 0x0002 85 #define EA_NEW 0x0004 86 #define EA_MALLOC 0x0008 87 88 89 /* 90 * Mapping of on-disk attribute names: for on-disk attribute names with an 91 * unknown prefix (not "system.", "user.", "security.", or "trusted."), the 92 * prefix "os2." is prepended. On the way back to disk, "os2." prefixes are 93 * stripped and we make sure that the remaining name does not start with one 94 * of the know prefixes. 95 */ 96 97 static int is_known_namespace(const char *name) 98 { 99 if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) && 100 strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) && 101 strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) && 102 strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN)) 103 return false; 104 105 return true; 106 } 107 108 static inline int name_size(struct jfs_ea *ea) 109 { 110 if (is_known_namespace(ea->name)) 111 return ea->namelen; 112 else 113 return ea->namelen + XATTR_OS2_PREFIX_LEN; 114 } 115 116 static inline int copy_name(char *buffer, struct jfs_ea *ea) 117 { 118 int len = ea->namelen; 119 120 if (!is_known_namespace(ea->name)) { 121 memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN); 122 buffer += XATTR_OS2_PREFIX_LEN; 123 len += XATTR_OS2_PREFIX_LEN; 124 } 125 memcpy(buffer, ea->name, ea->namelen); 126 buffer[ea->namelen] = 0; 127 128 return len; 129 } 130 131 /* Forward references */ 132 static void ea_release(struct inode *inode, struct ea_buffer *ea_buf); 133 134 /* 135 * NAME: ea_write_inline 136 * 137 * FUNCTION: Attempt to write an EA inline if area is available 138 * 139 * PRE CONDITIONS: 140 * Already verified that the specified EA is small enough to fit inline 141 * 142 * PARAMETERS: 143 * ip - Inode pointer 144 * ealist - EA list pointer 145 * size - size of ealist in bytes 146 * ea - dxd_t structure to be filled in with necessary EA information 147 * if we successfully copy the EA inline 148 * 149 * NOTES: 150 * Checks if the inode's inline area is available. If so, copies EA inline 151 * and sets <ea> fields appropriately. Otherwise, returns failure, EA will 152 * have to be put into an extent. 153 * 154 * RETURNS: 0 for successful copy to inline area; -1 if area not available 155 */ 156 static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist, 157 int size, dxd_t * ea) 158 { 159 struct jfs_inode_info *ji = JFS_IP(ip); 160 161 /* 162 * Make sure we have an EA -- the NULL EA list is valid, but you 163 * can't copy it! 164 */ 165 if (ealist && size > sizeof (struct jfs_ea_list)) { 166 assert(size <= sizeof (ji->i_inline_ea)); 167 168 /* 169 * See if the space is available or if it is already being 170 * used for an inline EA. 171 */ 172 if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE)) 173 return -EPERM; 174 175 DXDsize(ea, size); 176 DXDlength(ea, 0); 177 DXDaddress(ea, 0); 178 memcpy(ji->i_inline_ea, ealist, size); 179 ea->flag = DXD_INLINE; 180 ji->mode2 &= ~INLINEEA; 181 } else { 182 ea->flag = 0; 183 DXDsize(ea, 0); 184 DXDlength(ea, 0); 185 DXDaddress(ea, 0); 186 187 /* Free up INLINE area */ 188 if (ji->ea.flag & DXD_INLINE) 189 ji->mode2 |= INLINEEA; 190 } 191 192 return 0; 193 } 194 195 /* 196 * NAME: ea_write 197 * 198 * FUNCTION: Write an EA for an inode 199 * 200 * PRE CONDITIONS: EA has been verified 201 * 202 * PARAMETERS: 203 * ip - Inode pointer 204 * ealist - EA list pointer 205 * size - size of ealist in bytes 206 * ea - dxd_t structure to be filled in appropriately with where the 207 * EA was copied 208 * 209 * NOTES: Will write EA inline if able to, otherwise allocates blocks for an 210 * extent and synchronously writes it to those blocks. 211 * 212 * RETURNS: 0 for success; Anything else indicates failure 213 */ 214 static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size, 215 dxd_t * ea) 216 { 217 struct super_block *sb = ip->i_sb; 218 struct jfs_inode_info *ji = JFS_IP(ip); 219 struct jfs_sb_info *sbi = JFS_SBI(sb); 220 int nblocks; 221 s64 blkno; 222 int rc = 0, i; 223 char *cp; 224 s32 nbytes, nb; 225 s32 bytes_to_write; 226 struct metapage *mp; 227 228 /* 229 * Quick check to see if this is an in-linable EA. Short EAs 230 * and empty EAs are all in-linable, provided the space exists. 231 */ 232 if (!ealist || size <= sizeof (ji->i_inline_ea)) { 233 if (!ea_write_inline(ip, ealist, size, ea)) 234 return 0; 235 } 236 237 /* figure out how many blocks we need */ 238 nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits; 239 240 /* Allocate new blocks to quota. */ 241 rc = dquot_alloc_block(ip, nblocks); 242 if (rc) 243 return rc; 244 245 rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno); 246 if (rc) { 247 /*Rollback quota allocation. */ 248 dquot_free_block(ip, nblocks); 249 return rc; 250 } 251 252 /* 253 * Now have nblocks worth of storage to stuff into the FEALIST. 254 * loop over the FEALIST copying data into the buffer one page at 255 * a time. 256 */ 257 cp = (char *) ealist; 258 nbytes = size; 259 for (i = 0; i < nblocks; i += sbi->nbperpage) { 260 /* 261 * Determine how many bytes for this request, and round up to 262 * the nearest aggregate block size 263 */ 264 nb = min(PSIZE, nbytes); 265 bytes_to_write = 266 ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits)) 267 << sb->s_blocksize_bits; 268 269 if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) { 270 rc = -EIO; 271 goto failed; 272 } 273 274 memcpy(mp->data, cp, nb); 275 276 /* 277 * We really need a way to propagate errors for 278 * forced writes like this one. --hch 279 * 280 * (__write_metapage => release_metapage => flush_metapage) 281 */ 282 #ifdef _JFS_FIXME 283 if ((rc = flush_metapage(mp))) { 284 /* 285 * the write failed -- this means that the buffer 286 * is still assigned and the blocks are not being 287 * used. this seems like the best error recovery 288 * we can get ... 289 */ 290 goto failed; 291 } 292 #else 293 flush_metapage(mp); 294 #endif 295 296 cp += PSIZE; 297 nbytes -= nb; 298 } 299 300 ea->flag = DXD_EXTENT; 301 DXDsize(ea, le32_to_cpu(ealist->size)); 302 DXDlength(ea, nblocks); 303 DXDaddress(ea, blkno); 304 305 /* Free up INLINE area */ 306 if (ji->ea.flag & DXD_INLINE) 307 ji->mode2 |= INLINEEA; 308 309 return 0; 310 311 failed: 312 /* Rollback quota allocation. */ 313 dquot_free_block(ip, nblocks); 314 315 dbFree(ip, blkno, nblocks); 316 return rc; 317 } 318 319 /* 320 * NAME: ea_read_inline 321 * 322 * FUNCTION: Read an inlined EA into user's buffer 323 * 324 * PARAMETERS: 325 * ip - Inode pointer 326 * ealist - Pointer to buffer to fill in with EA 327 * 328 * RETURNS: 0 329 */ 330 static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist) 331 { 332 struct jfs_inode_info *ji = JFS_IP(ip); 333 int ea_size = sizeDXD(&ji->ea); 334 335 if (ea_size == 0) { 336 ealist->size = 0; 337 return 0; 338 } 339 340 /* Sanity Check */ 341 if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea))) 342 return -EIO; 343 if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size) 344 != ea_size) 345 return -EIO; 346 347 memcpy(ealist, ji->i_inline_ea, ea_size); 348 return 0; 349 } 350 351 /* 352 * NAME: ea_read 353 * 354 * FUNCTION: copy EA data into user's buffer 355 * 356 * PARAMETERS: 357 * ip - Inode pointer 358 * ealist - Pointer to buffer to fill in with EA 359 * 360 * NOTES: If EA is inline calls ea_read_inline() to copy EA. 361 * 362 * RETURNS: 0 for success; other indicates failure 363 */ 364 static int ea_read(struct inode *ip, struct jfs_ea_list *ealist) 365 { 366 struct super_block *sb = ip->i_sb; 367 struct jfs_inode_info *ji = JFS_IP(ip); 368 struct jfs_sb_info *sbi = JFS_SBI(sb); 369 int nblocks; 370 s64 blkno; 371 char *cp = (char *) ealist; 372 int i; 373 int nbytes, nb; 374 s32 bytes_to_read; 375 struct metapage *mp; 376 377 /* quick check for in-line EA */ 378 if (ji->ea.flag & DXD_INLINE) 379 return ea_read_inline(ip, ealist); 380 381 nbytes = sizeDXD(&ji->ea); 382 if (!nbytes) { 383 jfs_error(sb, "nbytes is 0\n"); 384 return -EIO; 385 } 386 387 /* 388 * Figure out how many blocks were allocated when this EA list was 389 * originally written to disk. 390 */ 391 nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage; 392 blkno = addressDXD(&ji->ea) << sbi->l2nbperpage; 393 394 /* 395 * I have found the disk blocks which were originally used to store 396 * the FEALIST. now i loop over each contiguous block copying the 397 * data into the buffer. 398 */ 399 for (i = 0; i < nblocks; i += sbi->nbperpage) { 400 /* 401 * Determine how many bytes for this request, and round up to 402 * the nearest aggregate block size 403 */ 404 nb = min(PSIZE, nbytes); 405 bytes_to_read = 406 ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits)) 407 << sb->s_blocksize_bits; 408 409 if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1))) 410 return -EIO; 411 412 memcpy(cp, mp->data, nb); 413 release_metapage(mp); 414 415 cp += PSIZE; 416 nbytes -= nb; 417 } 418 419 return 0; 420 } 421 422 /* 423 * NAME: ea_get 424 * 425 * FUNCTION: Returns buffer containing existing extended attributes. 426 * The size of the buffer will be the larger of the existing 427 * attributes size, or min_size. 428 * 429 * The buffer, which may be inlined in the inode or in the 430 * page cache must be release by calling ea_release or ea_put 431 * 432 * PARAMETERS: 433 * inode - Inode pointer 434 * ea_buf - Structure to be populated with ealist and its metadata 435 * min_size- minimum size of buffer to be returned 436 * 437 * RETURNS: 0 for success; Other indicates failure 438 */ 439 static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) 440 { 441 struct jfs_inode_info *ji = JFS_IP(inode); 442 struct super_block *sb = inode->i_sb; 443 int size; 444 int ea_size = sizeDXD(&ji->ea); 445 int blocks_needed, current_blocks; 446 s64 blkno; 447 int rc; 448 int quota_allocation = 0; 449 450 /* When fsck.jfs clears a bad ea, it doesn't clear the size */ 451 if (ji->ea.flag == 0) 452 ea_size = 0; 453 454 if (ea_size == 0) { 455 if (min_size == 0) { 456 ea_buf->flag = 0; 457 ea_buf->max_size = 0; 458 ea_buf->xattr = NULL; 459 return 0; 460 } 461 if ((min_size <= sizeof (ji->i_inline_ea)) && 462 (ji->mode2 & INLINEEA)) { 463 ea_buf->flag = EA_INLINE | EA_NEW; 464 ea_buf->max_size = sizeof (ji->i_inline_ea); 465 ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea; 466 DXDlength(&ea_buf->new_ea, 0); 467 DXDaddress(&ea_buf->new_ea, 0); 468 ea_buf->new_ea.flag = DXD_INLINE; 469 DXDsize(&ea_buf->new_ea, min_size); 470 return 0; 471 } 472 current_blocks = 0; 473 } else if (ji->ea.flag & DXD_INLINE) { 474 if (min_size <= sizeof (ji->i_inline_ea)) { 475 ea_buf->flag = EA_INLINE; 476 ea_buf->max_size = sizeof (ji->i_inline_ea); 477 ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea; 478 goto size_check; 479 } 480 current_blocks = 0; 481 } else { 482 if (!(ji->ea.flag & DXD_EXTENT)) { 483 jfs_error(sb, "invalid ea.flag\n"); 484 return -EIO; 485 } 486 current_blocks = (ea_size + sb->s_blocksize - 1) >> 487 sb->s_blocksize_bits; 488 } 489 size = max(min_size, ea_size); 490 491 if (size > PSIZE) { 492 /* 493 * To keep the rest of the code simple. Allocate a 494 * contiguous buffer to work with 495 */ 496 ea_buf->xattr = kmalloc(size, GFP_KERNEL); 497 if (ea_buf->xattr == NULL) 498 return -ENOMEM; 499 500 ea_buf->flag = EA_MALLOC; 501 ea_buf->max_size = (size + sb->s_blocksize - 1) & 502 ~(sb->s_blocksize - 1); 503 504 if (ea_size == 0) 505 return 0; 506 507 if ((rc = ea_read(inode, ea_buf->xattr))) { 508 kfree(ea_buf->xattr); 509 ea_buf->xattr = NULL; 510 return rc; 511 } 512 goto size_check; 513 } 514 blocks_needed = (min_size + sb->s_blocksize - 1) >> 515 sb->s_blocksize_bits; 516 517 if (blocks_needed > current_blocks) { 518 /* Allocate new blocks to quota. */ 519 rc = dquot_alloc_block(inode, blocks_needed); 520 if (rc) 521 return -EDQUOT; 522 523 quota_allocation = blocks_needed; 524 525 rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed, 526 &blkno); 527 if (rc) 528 goto clean_up; 529 530 DXDlength(&ea_buf->new_ea, blocks_needed); 531 DXDaddress(&ea_buf->new_ea, blkno); 532 ea_buf->new_ea.flag = DXD_EXTENT; 533 DXDsize(&ea_buf->new_ea, min_size); 534 535 ea_buf->flag = EA_EXTENT | EA_NEW; 536 537 ea_buf->mp = get_metapage(inode, blkno, 538 blocks_needed << sb->s_blocksize_bits, 539 1); 540 if (ea_buf->mp == NULL) { 541 dbFree(inode, blkno, (s64) blocks_needed); 542 rc = -EIO; 543 goto clean_up; 544 } 545 ea_buf->xattr = ea_buf->mp->data; 546 ea_buf->max_size = (min_size + sb->s_blocksize - 1) & 547 ~(sb->s_blocksize - 1); 548 if (ea_size == 0) 549 return 0; 550 if ((rc = ea_read(inode, ea_buf->xattr))) { 551 discard_metapage(ea_buf->mp); 552 dbFree(inode, blkno, (s64) blocks_needed); 553 goto clean_up; 554 } 555 goto size_check; 556 } 557 ea_buf->flag = EA_EXTENT; 558 ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea), 559 lengthDXD(&ji->ea) << sb->s_blocksize_bits, 560 1); 561 if (ea_buf->mp == NULL) { 562 rc = -EIO; 563 goto clean_up; 564 } 565 ea_buf->xattr = ea_buf->mp->data; 566 ea_buf->max_size = (ea_size + sb->s_blocksize - 1) & 567 ~(sb->s_blocksize - 1); 568 569 size_check: 570 if (EALIST_SIZE(ea_buf->xattr) != ea_size) { 571 printk(KERN_ERR "ea_get: invalid extended attribute\n"); 572 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, 573 ea_buf->xattr, ea_size, 1); 574 ea_release(inode, ea_buf); 575 rc = -EIO; 576 goto clean_up; 577 } 578 579 return ea_size; 580 581 clean_up: 582 /* Rollback quota allocation */ 583 if (quota_allocation) 584 dquot_free_block(inode, quota_allocation); 585 586 return (rc); 587 } 588 589 static void ea_release(struct inode *inode, struct ea_buffer *ea_buf) 590 { 591 if (ea_buf->flag & EA_MALLOC) 592 kfree(ea_buf->xattr); 593 else if (ea_buf->flag & EA_EXTENT) { 594 assert(ea_buf->mp); 595 release_metapage(ea_buf->mp); 596 597 if (ea_buf->flag & EA_NEW) 598 dbFree(inode, addressDXD(&ea_buf->new_ea), 599 lengthDXD(&ea_buf->new_ea)); 600 } 601 } 602 603 static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf, 604 int new_size) 605 { 606 struct jfs_inode_info *ji = JFS_IP(inode); 607 unsigned long old_blocks, new_blocks; 608 int rc = 0; 609 610 if (new_size == 0) { 611 ea_release(inode, ea_buf); 612 ea_buf = NULL; 613 } else if (ea_buf->flag & EA_INLINE) { 614 assert(new_size <= sizeof (ji->i_inline_ea)); 615 ji->mode2 &= ~INLINEEA; 616 ea_buf->new_ea.flag = DXD_INLINE; 617 DXDsize(&ea_buf->new_ea, new_size); 618 DXDaddress(&ea_buf->new_ea, 0); 619 DXDlength(&ea_buf->new_ea, 0); 620 } else if (ea_buf->flag & EA_MALLOC) { 621 rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea); 622 kfree(ea_buf->xattr); 623 } else if (ea_buf->flag & EA_NEW) { 624 /* We have already allocated a new dxd */ 625 flush_metapage(ea_buf->mp); 626 } else { 627 /* ->xattr must point to original ea's metapage */ 628 rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea); 629 discard_metapage(ea_buf->mp); 630 } 631 if (rc) 632 return rc; 633 634 old_blocks = new_blocks = 0; 635 636 if (ji->ea.flag & DXD_EXTENT) { 637 invalidate_dxd_metapages(inode, ji->ea); 638 old_blocks = lengthDXD(&ji->ea); 639 } 640 641 if (ea_buf) { 642 txEA(tid, inode, &ji->ea, &ea_buf->new_ea); 643 if (ea_buf->new_ea.flag & DXD_EXTENT) { 644 new_blocks = lengthDXD(&ea_buf->new_ea); 645 if (ji->ea.flag & DXD_INLINE) 646 ji->mode2 |= INLINEEA; 647 } 648 ji->ea = ea_buf->new_ea; 649 } else { 650 txEA(tid, inode, &ji->ea, NULL); 651 if (ji->ea.flag & DXD_INLINE) 652 ji->mode2 |= INLINEEA; 653 ji->ea.flag = 0; 654 ji->ea.size = 0; 655 } 656 657 /* If old blocks exist, they must be removed from quota allocation. */ 658 if (old_blocks) 659 dquot_free_block(inode, old_blocks); 660 661 inode->i_ctime = current_time(inode); 662 663 return 0; 664 } 665 666 int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, 667 const void *value, size_t value_len, int flags) 668 { 669 struct jfs_ea_list *ealist; 670 struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL; 671 struct ea_buffer ea_buf; 672 int old_ea_size = 0; 673 int xattr_size; 674 int new_size; 675 int namelen = strlen(name); 676 int found = 0; 677 int rc; 678 int length; 679 680 down_write(&JFS_IP(inode)->xattr_sem); 681 682 xattr_size = ea_get(inode, &ea_buf, 0); 683 if (xattr_size < 0) { 684 rc = xattr_size; 685 goto out; 686 } 687 688 again: 689 ealist = (struct jfs_ea_list *) ea_buf.xattr; 690 new_size = sizeof (struct jfs_ea_list); 691 692 if (xattr_size) { 693 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); 694 ea = NEXT_EA(ea)) { 695 if ((namelen == ea->namelen) && 696 (memcmp(name, ea->name, namelen) == 0)) { 697 found = 1; 698 if (flags & XATTR_CREATE) { 699 rc = -EEXIST; 700 goto release; 701 } 702 old_ea = ea; 703 old_ea_size = EA_SIZE(ea); 704 next_ea = NEXT_EA(ea); 705 } else 706 new_size += EA_SIZE(ea); 707 } 708 } 709 710 if (!found) { 711 if (flags & XATTR_REPLACE) { 712 rc = -ENODATA; 713 goto release; 714 } 715 if (value == NULL) { 716 rc = 0; 717 goto release; 718 } 719 } 720 if (value) 721 new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len; 722 723 if (new_size > ea_buf.max_size) { 724 /* 725 * We need to allocate more space for merged ea list. 726 * We should only have loop to again: once. 727 */ 728 ea_release(inode, &ea_buf); 729 xattr_size = ea_get(inode, &ea_buf, new_size); 730 if (xattr_size < 0) { 731 rc = xattr_size; 732 goto out; 733 } 734 goto again; 735 } 736 737 /* Remove old ea of the same name */ 738 if (found) { 739 /* number of bytes following target EA */ 740 length = (char *) END_EALIST(ealist) - (char *) next_ea; 741 if (length > 0) 742 memmove(old_ea, next_ea, length); 743 xattr_size -= old_ea_size; 744 } 745 746 /* Add new entry to the end */ 747 if (value) { 748 if (xattr_size == 0) 749 /* Completely new ea list */ 750 xattr_size = sizeof (struct jfs_ea_list); 751 752 /* 753 * The size of EA value is limitted by on-disk format up to 754 * __le16, there would be an overflow if the size is equal 755 * to XATTR_SIZE_MAX (65536). In order to avoid this issue, 756 * we can pre-checkup the value size against USHRT_MAX, and 757 * return -E2BIG in this case, which is consistent with the 758 * VFS setxattr interface. 759 */ 760 if (value_len >= USHRT_MAX) { 761 rc = -E2BIG; 762 goto release; 763 } 764 765 ea = (struct jfs_ea *) ((char *) ealist + xattr_size); 766 ea->flag = 0; 767 ea->namelen = namelen; 768 ea->valuelen = (cpu_to_le16(value_len)); 769 memcpy(ea->name, name, namelen); 770 ea->name[namelen] = 0; 771 if (value_len) 772 memcpy(&ea->name[namelen + 1], value, value_len); 773 xattr_size += EA_SIZE(ea); 774 } 775 776 /* DEBUG - If we did this right, these number match */ 777 if (xattr_size != new_size) { 778 printk(KERN_ERR 779 "__jfs_setxattr: xattr_size = %d, new_size = %d\n", 780 xattr_size, new_size); 781 782 rc = -EINVAL; 783 goto release; 784 } 785 786 /* 787 * If we're left with an empty list, there's no ea 788 */ 789 if (new_size == sizeof (struct jfs_ea_list)) 790 new_size = 0; 791 792 ealist->size = cpu_to_le32(new_size); 793 794 rc = ea_put(tid, inode, &ea_buf, new_size); 795 796 goto out; 797 release: 798 ea_release(inode, &ea_buf); 799 out: 800 up_write(&JFS_IP(inode)->xattr_sem); 801 802 return rc; 803 } 804 805 ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data, 806 size_t buf_size) 807 { 808 struct jfs_ea_list *ealist; 809 struct jfs_ea *ea; 810 struct ea_buffer ea_buf; 811 int xattr_size; 812 ssize_t size; 813 int namelen = strlen(name); 814 char *value; 815 816 down_read(&JFS_IP(inode)->xattr_sem); 817 818 xattr_size = ea_get(inode, &ea_buf, 0); 819 820 if (xattr_size < 0) { 821 size = xattr_size; 822 goto out; 823 } 824 825 if (xattr_size == 0) 826 goto not_found; 827 828 ealist = (struct jfs_ea_list *) ea_buf.xattr; 829 830 /* Find the named attribute */ 831 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) 832 if ((namelen == ea->namelen) && 833 memcmp(name, ea->name, namelen) == 0) { 834 /* Found it */ 835 size = le16_to_cpu(ea->valuelen); 836 if (!data) 837 goto release; 838 else if (size > buf_size) { 839 size = -ERANGE; 840 goto release; 841 } 842 value = ((char *) &ea->name) + ea->namelen + 1; 843 memcpy(data, value, size); 844 goto release; 845 } 846 not_found: 847 size = -ENODATA; 848 release: 849 ea_release(inode, &ea_buf); 850 out: 851 up_read(&JFS_IP(inode)->xattr_sem); 852 853 return size; 854 } 855 856 /* 857 * No special permissions are needed to list attributes except for trusted.* 858 */ 859 static inline int can_list(struct jfs_ea *ea) 860 { 861 return (strncmp(ea->name, XATTR_TRUSTED_PREFIX, 862 XATTR_TRUSTED_PREFIX_LEN) || 863 capable(CAP_SYS_ADMIN)); 864 } 865 866 ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size) 867 { 868 struct inode *inode = d_inode(dentry); 869 char *buffer; 870 ssize_t size = 0; 871 int xattr_size; 872 struct jfs_ea_list *ealist; 873 struct jfs_ea *ea; 874 struct ea_buffer ea_buf; 875 876 down_read(&JFS_IP(inode)->xattr_sem); 877 878 xattr_size = ea_get(inode, &ea_buf, 0); 879 if (xattr_size < 0) { 880 size = xattr_size; 881 goto out; 882 } 883 884 if (xattr_size == 0) 885 goto release; 886 887 ealist = (struct jfs_ea_list *) ea_buf.xattr; 888 889 /* compute required size of list */ 890 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) { 891 if (can_list(ea)) 892 size += name_size(ea) + 1; 893 } 894 895 if (!data) 896 goto release; 897 898 if (size > buf_size) { 899 size = -ERANGE; 900 goto release; 901 } 902 903 /* Copy attribute names to buffer */ 904 buffer = data; 905 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) { 906 if (can_list(ea)) { 907 int namelen = copy_name(buffer, ea); 908 buffer += namelen + 1; 909 } 910 } 911 912 release: 913 ea_release(inode, &ea_buf); 914 out: 915 up_read(&JFS_IP(inode)->xattr_sem); 916 return size; 917 } 918 919 static int __jfs_xattr_set(struct inode *inode, const char *name, 920 const void *value, size_t size, int flags) 921 { 922 struct jfs_inode_info *ji = JFS_IP(inode); 923 tid_t tid; 924 int rc; 925 926 tid = txBegin(inode->i_sb, 0); 927 mutex_lock(&ji->commit_mutex); 928 rc = __jfs_setxattr(tid, inode, name, value, size, flags); 929 if (!rc) 930 rc = txCommit(tid, 1, &inode, 0); 931 txEnd(tid); 932 mutex_unlock(&ji->commit_mutex); 933 934 return rc; 935 } 936 937 static int jfs_xattr_get(const struct xattr_handler *handler, 938 struct dentry *unused, struct inode *inode, 939 const char *name, void *value, size_t size) 940 { 941 name = xattr_full_name(handler, name); 942 return __jfs_getxattr(inode, name, value, size); 943 } 944 945 static int jfs_xattr_set(const struct xattr_handler *handler, 946 struct dentry *unused, struct inode *inode, 947 const char *name, const void *value, 948 size_t size, int flags) 949 { 950 name = xattr_full_name(handler, name); 951 return __jfs_xattr_set(inode, name, value, size, flags); 952 } 953 954 static int jfs_xattr_get_os2(const struct xattr_handler *handler, 955 struct dentry *unused, struct inode *inode, 956 const char *name, void *value, size_t size) 957 { 958 if (is_known_namespace(name)) 959 return -EOPNOTSUPP; 960 return __jfs_getxattr(inode, name, value, size); 961 } 962 963 static int jfs_xattr_set_os2(const struct xattr_handler *handler, 964 struct dentry *unused, struct inode *inode, 965 const char *name, const void *value, 966 size_t size, int flags) 967 { 968 if (is_known_namespace(name)) 969 return -EOPNOTSUPP; 970 return __jfs_xattr_set(inode, name, value, size, flags); 971 } 972 973 static const struct xattr_handler jfs_user_xattr_handler = { 974 .prefix = XATTR_USER_PREFIX, 975 .get = jfs_xattr_get, 976 .set = jfs_xattr_set, 977 }; 978 979 static const struct xattr_handler jfs_os2_xattr_handler = { 980 .prefix = XATTR_OS2_PREFIX, 981 .get = jfs_xattr_get_os2, 982 .set = jfs_xattr_set_os2, 983 }; 984 985 static const struct xattr_handler jfs_security_xattr_handler = { 986 .prefix = XATTR_SECURITY_PREFIX, 987 .get = jfs_xattr_get, 988 .set = jfs_xattr_set, 989 }; 990 991 static const struct xattr_handler jfs_trusted_xattr_handler = { 992 .prefix = XATTR_TRUSTED_PREFIX, 993 .get = jfs_xattr_get, 994 .set = jfs_xattr_set, 995 }; 996 997 const struct xattr_handler *jfs_xattr_handlers[] = { 998 #ifdef CONFIG_JFS_POSIX_ACL 999 &posix_acl_access_xattr_handler, 1000 &posix_acl_default_xattr_handler, 1001 #endif 1002 &jfs_os2_xattr_handler, 1003 &jfs_user_xattr_handler, 1004 &jfs_security_xattr_handler, 1005 &jfs_trusted_xattr_handler, 1006 NULL, 1007 }; 1008 1009 1010 #ifdef CONFIG_JFS_SECURITY 1011 static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array, 1012 void *fs_info) 1013 { 1014 const struct xattr *xattr; 1015 tid_t *tid = fs_info; 1016 char *name; 1017 int err = 0; 1018 1019 for (xattr = xattr_array; xattr->name != NULL; xattr++) { 1020 name = kmalloc(XATTR_SECURITY_PREFIX_LEN + 1021 strlen(xattr->name) + 1, GFP_NOFS); 1022 if (!name) { 1023 err = -ENOMEM; 1024 break; 1025 } 1026 strcpy(name, XATTR_SECURITY_PREFIX); 1027 strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); 1028 1029 err = __jfs_setxattr(*tid, inode, name, 1030 xattr->value, xattr->value_len, 0); 1031 kfree(name); 1032 if (err < 0) 1033 break; 1034 } 1035 return err; 1036 } 1037 1038 int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir, 1039 const struct qstr *qstr) 1040 { 1041 return security_inode_init_security(inode, dir, qstr, 1042 &jfs_initxattrs, &tid); 1043 } 1044 #endif 1045