1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 4 * Copyright (c) 2013 Red Hat, Inc. 5 * All Rights Reserved. 6 */ 7 #include "xfs.h" 8 #include "xfs_fs.h" 9 #include "xfs_shared.h" 10 #include "xfs_format.h" 11 #include "xfs_log_format.h" 12 #include "xfs_trans_resv.h" 13 #include "xfs_mount.h" 14 #include "xfs_da_format.h" 15 #include "xfs_inode.h" 16 #include "xfs_trans.h" 17 #include "xfs_bmap.h" 18 #include "xfs_attr.h" 19 #include "xfs_attr_sf.h" 20 #include "xfs_attr_leaf.h" 21 #include "xfs_error.h" 22 #include "xfs_trace.h" 23 #include "xfs_dir2.h" 24 25 STATIC int 26 xfs_attr_shortform_compare(const void *a, const void *b) 27 { 28 xfs_attr_sf_sort_t *sa, *sb; 29 30 sa = (xfs_attr_sf_sort_t *)a; 31 sb = (xfs_attr_sf_sort_t *)b; 32 if (sa->hash < sb->hash) { 33 return -1; 34 } else if (sa->hash > sb->hash) { 35 return 1; 36 } else { 37 return sa->entno - sb->entno; 38 } 39 } 40 41 #define XFS_ISRESET_CURSOR(cursor) \ 42 (!((cursor)->initted) && !((cursor)->hashval) && \ 43 !((cursor)->blkno) && !((cursor)->offset)) 44 /* 45 * Copy out entries of shortform attribute lists for attr_list(). 46 * Shortform attribute lists are not stored in hashval sorted order. 47 * If the output buffer is not large enough to hold them all, then we 48 * we have to calculate each entries' hashvalue and sort them before 49 * we can begin returning them to the user. 50 */ 51 static int 52 xfs_attr_shortform_list( 53 struct xfs_attr_list_context *context) 54 { 55 struct xfs_attrlist_cursor_kern *cursor = &context->cursor; 56 struct xfs_inode *dp = context->dp; 57 struct xfs_attr_sf_sort *sbuf, *sbp; 58 struct xfs_attr_shortform *sf; 59 struct xfs_attr_sf_entry *sfe; 60 int sbsize, nsbuf, count, i; 61 int error = 0; 62 63 ASSERT(dp->i_afp != NULL); 64 sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data; 65 ASSERT(sf != NULL); 66 if (!sf->hdr.count) 67 return 0; 68 69 trace_xfs_attr_list_sf(context); 70 71 /* 72 * If the buffer is large enough and the cursor is at the start, 73 * do not bother with sorting since we will return everything in 74 * one buffer and another call using the cursor won't need to be 75 * made. 76 * Note the generous fudge factor of 16 overhead bytes per entry. 77 * If bufsize is zero then put_listent must be a search function 78 * and can just scan through what we have. 79 */ 80 if (context->bufsize == 0 || 81 (XFS_ISRESET_CURSOR(cursor) && 82 (dp->i_afp->if_bytes + sf->hdr.count * 16) < context->bufsize)) { 83 for (i = 0, sfe = &sf->list[0]; i < sf->hdr.count; i++) { 84 if (XFS_IS_CORRUPT(context->dp->i_mount, 85 !xfs_attr_namecheck(sfe->nameval, 86 sfe->namelen))) 87 return -EFSCORRUPTED; 88 context->put_listent(context, 89 sfe->flags, 90 sfe->nameval, 91 (int)sfe->namelen, 92 (int)sfe->valuelen); 93 /* 94 * Either search callback finished early or 95 * didn't fit it all in the buffer after all. 96 */ 97 if (context->seen_enough) 98 break; 99 sfe = XFS_ATTR_SF_NEXTENTRY(sfe); 100 } 101 trace_xfs_attr_list_sf_all(context); 102 return 0; 103 } 104 105 /* do no more for a search callback */ 106 if (context->bufsize == 0) 107 return 0; 108 109 /* 110 * It didn't all fit, so we have to sort everything on hashval. 111 */ 112 sbsize = sf->hdr.count * sizeof(*sbuf); 113 sbp = sbuf = kmem_alloc(sbsize, KM_NOFS); 114 115 /* 116 * Scan the attribute list for the rest of the entries, storing 117 * the relevant info from only those that match into a buffer. 118 */ 119 nsbuf = 0; 120 for (i = 0, sfe = &sf->list[0]; i < sf->hdr.count; i++) { 121 if (unlikely( 122 ((char *)sfe < (char *)sf) || 123 ((char *)sfe >= ((char *)sf + dp->i_afp->if_bytes)))) { 124 XFS_CORRUPTION_ERROR("xfs_attr_shortform_list", 125 XFS_ERRLEVEL_LOW, 126 context->dp->i_mount, sfe, 127 sizeof(*sfe)); 128 kmem_free(sbuf); 129 return -EFSCORRUPTED; 130 } 131 132 sbp->entno = i; 133 sbp->hash = xfs_da_hashname(sfe->nameval, sfe->namelen); 134 sbp->name = sfe->nameval; 135 sbp->namelen = sfe->namelen; 136 /* These are bytes, and both on-disk, don't endian-flip */ 137 sbp->valuelen = sfe->valuelen; 138 sbp->flags = sfe->flags; 139 sfe = XFS_ATTR_SF_NEXTENTRY(sfe); 140 sbp++; 141 nsbuf++; 142 } 143 144 /* 145 * Sort the entries on hash then entno. 146 */ 147 xfs_sort(sbuf, nsbuf, sizeof(*sbuf), xfs_attr_shortform_compare); 148 149 /* 150 * Re-find our place IN THE SORTED LIST. 151 */ 152 count = 0; 153 cursor->initted = 1; 154 cursor->blkno = 0; 155 for (sbp = sbuf, i = 0; i < nsbuf; i++, sbp++) { 156 if (sbp->hash == cursor->hashval) { 157 if (cursor->offset == count) { 158 break; 159 } 160 count++; 161 } else if (sbp->hash > cursor->hashval) { 162 break; 163 } 164 } 165 if (i == nsbuf) 166 goto out; 167 168 /* 169 * Loop putting entries into the user buffer. 170 */ 171 for ( ; i < nsbuf; i++, sbp++) { 172 if (cursor->hashval != sbp->hash) { 173 cursor->hashval = sbp->hash; 174 cursor->offset = 0; 175 } 176 if (XFS_IS_CORRUPT(context->dp->i_mount, 177 !xfs_attr_namecheck(sbp->name, 178 sbp->namelen))) { 179 error = -EFSCORRUPTED; 180 goto out; 181 } 182 context->put_listent(context, 183 sbp->flags, 184 sbp->name, 185 sbp->namelen, 186 sbp->valuelen); 187 if (context->seen_enough) 188 break; 189 cursor->offset++; 190 } 191 out: 192 kmem_free(sbuf); 193 return error; 194 } 195 196 /* 197 * We didn't find the block & hash mentioned in the cursor state, so 198 * walk down the attr btree looking for the hash. 199 */ 200 STATIC int 201 xfs_attr_node_list_lookup( 202 struct xfs_attr_list_context *context, 203 struct xfs_attrlist_cursor_kern *cursor, 204 struct xfs_buf **pbp) 205 { 206 struct xfs_da3_icnode_hdr nodehdr; 207 struct xfs_da_intnode *node; 208 struct xfs_da_node_entry *btree; 209 struct xfs_inode *dp = context->dp; 210 struct xfs_mount *mp = dp->i_mount; 211 struct xfs_trans *tp = context->tp; 212 struct xfs_buf *bp; 213 int i; 214 int error = 0; 215 unsigned int expected_level = 0; 216 uint16_t magic; 217 218 ASSERT(*pbp == NULL); 219 cursor->blkno = 0; 220 for (;;) { 221 error = xfs_da3_node_read(tp, dp, cursor->blkno, &bp, 222 XFS_ATTR_FORK); 223 if (error) 224 return error; 225 node = bp->b_addr; 226 magic = be16_to_cpu(node->hdr.info.magic); 227 if (magic == XFS_ATTR_LEAF_MAGIC || 228 magic == XFS_ATTR3_LEAF_MAGIC) 229 break; 230 if (magic != XFS_DA_NODE_MAGIC && 231 magic != XFS_DA3_NODE_MAGIC) { 232 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, 233 node, sizeof(*node)); 234 goto out_corruptbuf; 235 } 236 237 xfs_da3_node_hdr_from_disk(mp, &nodehdr, node); 238 239 /* Tree taller than we can handle; bail out! */ 240 if (nodehdr.level >= XFS_DA_NODE_MAXDEPTH) 241 goto out_corruptbuf; 242 243 /* Check the level from the root node. */ 244 if (cursor->blkno == 0) 245 expected_level = nodehdr.level - 1; 246 else if (expected_level != nodehdr.level) 247 goto out_corruptbuf; 248 else 249 expected_level--; 250 251 btree = nodehdr.btree; 252 for (i = 0; i < nodehdr.count; btree++, i++) { 253 if (cursor->hashval <= be32_to_cpu(btree->hashval)) { 254 cursor->blkno = be32_to_cpu(btree->before); 255 trace_xfs_attr_list_node_descend(context, 256 btree); 257 break; 258 } 259 } 260 xfs_trans_brelse(tp, bp); 261 262 if (i == nodehdr.count) 263 return 0; 264 265 /* We can't point back to the root. */ 266 if (XFS_IS_CORRUPT(mp, cursor->blkno == 0)) 267 return -EFSCORRUPTED; 268 } 269 270 if (expected_level != 0) 271 goto out_corruptbuf; 272 273 *pbp = bp; 274 return 0; 275 276 out_corruptbuf: 277 xfs_buf_mark_corrupt(bp); 278 xfs_trans_brelse(tp, bp); 279 return -EFSCORRUPTED; 280 } 281 282 STATIC int 283 xfs_attr_node_list( 284 struct xfs_attr_list_context *context) 285 { 286 struct xfs_attrlist_cursor_kern *cursor = &context->cursor; 287 struct xfs_attr3_icleaf_hdr leafhdr; 288 struct xfs_attr_leafblock *leaf; 289 struct xfs_da_intnode *node; 290 struct xfs_buf *bp; 291 struct xfs_inode *dp = context->dp; 292 struct xfs_mount *mp = dp->i_mount; 293 int error = 0; 294 295 trace_xfs_attr_node_list(context); 296 297 cursor->initted = 1; 298 299 /* 300 * Do all sorts of validation on the passed-in cursor structure. 301 * If anything is amiss, ignore the cursor and look up the hashval 302 * starting from the btree root. 303 */ 304 bp = NULL; 305 if (cursor->blkno > 0) { 306 error = xfs_da3_node_read(context->tp, dp, cursor->blkno, &bp, 307 XFS_ATTR_FORK); 308 if ((error != 0) && (error != -EFSCORRUPTED)) 309 return error; 310 if (bp) { 311 struct xfs_attr_leaf_entry *entries; 312 313 node = bp->b_addr; 314 switch (be16_to_cpu(node->hdr.info.magic)) { 315 case XFS_DA_NODE_MAGIC: 316 case XFS_DA3_NODE_MAGIC: 317 trace_xfs_attr_list_wrong_blk(context); 318 xfs_trans_brelse(context->tp, bp); 319 bp = NULL; 320 break; 321 case XFS_ATTR_LEAF_MAGIC: 322 case XFS_ATTR3_LEAF_MAGIC: 323 leaf = bp->b_addr; 324 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, 325 &leafhdr, leaf); 326 entries = xfs_attr3_leaf_entryp(leaf); 327 if (cursor->hashval > be32_to_cpu( 328 entries[leafhdr.count - 1].hashval)) { 329 trace_xfs_attr_list_wrong_blk(context); 330 xfs_trans_brelse(context->tp, bp); 331 bp = NULL; 332 } else if (cursor->hashval <= be32_to_cpu( 333 entries[0].hashval)) { 334 trace_xfs_attr_list_wrong_blk(context); 335 xfs_trans_brelse(context->tp, bp); 336 bp = NULL; 337 } 338 break; 339 default: 340 trace_xfs_attr_list_wrong_blk(context); 341 xfs_trans_brelse(context->tp, bp); 342 bp = NULL; 343 } 344 } 345 } 346 347 /* 348 * We did not find what we expected given the cursor's contents, 349 * so we start from the top and work down based on the hash value. 350 * Note that start of node block is same as start of leaf block. 351 */ 352 if (bp == NULL) { 353 error = xfs_attr_node_list_lookup(context, cursor, &bp); 354 if (error || !bp) 355 return error; 356 } 357 ASSERT(bp != NULL); 358 359 /* 360 * Roll upward through the blocks, processing each leaf block in 361 * order. As long as there is space in the result buffer, keep 362 * adding the information. 363 */ 364 for (;;) { 365 leaf = bp->b_addr; 366 error = xfs_attr3_leaf_list_int(bp, context); 367 if (error) 368 break; 369 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf); 370 if (context->seen_enough || leafhdr.forw == 0) 371 break; 372 cursor->blkno = leafhdr.forw; 373 xfs_trans_brelse(context->tp, bp); 374 error = xfs_attr3_leaf_read(context->tp, dp, cursor->blkno, 375 &bp); 376 if (error) 377 return error; 378 } 379 xfs_trans_brelse(context->tp, bp); 380 return error; 381 } 382 383 /* 384 * Copy out attribute list entries for attr_list(), for leaf attribute lists. 385 */ 386 int 387 xfs_attr3_leaf_list_int( 388 struct xfs_buf *bp, 389 struct xfs_attr_list_context *context) 390 { 391 struct xfs_attrlist_cursor_kern *cursor = &context->cursor; 392 struct xfs_attr_leafblock *leaf; 393 struct xfs_attr3_icleaf_hdr ichdr; 394 struct xfs_attr_leaf_entry *entries; 395 struct xfs_attr_leaf_entry *entry; 396 int i; 397 struct xfs_mount *mp = context->dp->i_mount; 398 399 trace_xfs_attr_list_leaf(context); 400 401 leaf = bp->b_addr; 402 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf); 403 entries = xfs_attr3_leaf_entryp(leaf); 404 405 cursor->initted = 1; 406 407 /* 408 * Re-find our place in the leaf block if this is a new syscall. 409 */ 410 if (context->resynch) { 411 entry = &entries[0]; 412 for (i = 0; i < ichdr.count; entry++, i++) { 413 if (be32_to_cpu(entry->hashval) == cursor->hashval) { 414 if (cursor->offset == context->dupcnt) { 415 context->dupcnt = 0; 416 break; 417 } 418 context->dupcnt++; 419 } else if (be32_to_cpu(entry->hashval) > 420 cursor->hashval) { 421 context->dupcnt = 0; 422 break; 423 } 424 } 425 if (i == ichdr.count) { 426 trace_xfs_attr_list_notfound(context); 427 return 0; 428 } 429 } else { 430 entry = &entries[0]; 431 i = 0; 432 } 433 context->resynch = 0; 434 435 /* 436 * We have found our place, start copying out the new attributes. 437 */ 438 for (; i < ichdr.count; entry++, i++) { 439 char *name; 440 int namelen, valuelen; 441 442 if (be32_to_cpu(entry->hashval) != cursor->hashval) { 443 cursor->hashval = be32_to_cpu(entry->hashval); 444 cursor->offset = 0; 445 } 446 447 if ((entry->flags & XFS_ATTR_INCOMPLETE) && 448 !context->allow_incomplete) 449 continue; 450 451 if (entry->flags & XFS_ATTR_LOCAL) { 452 xfs_attr_leaf_name_local_t *name_loc; 453 454 name_loc = xfs_attr3_leaf_name_local(leaf, i); 455 name = name_loc->nameval; 456 namelen = name_loc->namelen; 457 valuelen = be16_to_cpu(name_loc->valuelen); 458 } else { 459 xfs_attr_leaf_name_remote_t *name_rmt; 460 461 name_rmt = xfs_attr3_leaf_name_remote(leaf, i); 462 name = name_rmt->name; 463 namelen = name_rmt->namelen; 464 valuelen = be32_to_cpu(name_rmt->valuelen); 465 } 466 467 if (XFS_IS_CORRUPT(context->dp->i_mount, 468 !xfs_attr_namecheck(name, namelen))) 469 return -EFSCORRUPTED; 470 context->put_listent(context, entry->flags, 471 name, namelen, valuelen); 472 if (context->seen_enough) 473 break; 474 cursor->offset++; 475 } 476 trace_xfs_attr_list_leaf_end(context); 477 return 0; 478 } 479 480 /* 481 * Copy out attribute entries for attr_list(), for leaf attribute lists. 482 */ 483 STATIC int 484 xfs_attr_leaf_list( 485 struct xfs_attr_list_context *context) 486 { 487 struct xfs_buf *bp; 488 int error; 489 490 trace_xfs_attr_leaf_list(context); 491 492 context->cursor.blkno = 0; 493 error = xfs_attr3_leaf_read(context->tp, context->dp, 0, &bp); 494 if (error) 495 return error; 496 497 error = xfs_attr3_leaf_list_int(bp, context); 498 xfs_trans_brelse(context->tp, bp); 499 return error; 500 } 501 502 int 503 xfs_attr_list_ilocked( 504 struct xfs_attr_list_context *context) 505 { 506 struct xfs_inode *dp = context->dp; 507 508 ASSERT(xfs_isilocked(dp, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); 509 510 /* 511 * Decide on what work routines to call based on the inode size. 512 */ 513 if (!xfs_inode_hasattr(dp)) 514 return 0; 515 if (dp->i_afp->if_format == XFS_DINODE_FMT_LOCAL) 516 return xfs_attr_shortform_list(context); 517 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) 518 return xfs_attr_leaf_list(context); 519 return xfs_attr_node_list(context); 520 } 521 522 int 523 xfs_attr_list( 524 struct xfs_attr_list_context *context) 525 { 526 struct xfs_inode *dp = context->dp; 527 uint lock_mode; 528 int error; 529 530 XFS_STATS_INC(dp->i_mount, xs_attr_list); 531 532 if (XFS_FORCED_SHUTDOWN(dp->i_mount)) 533 return -EIO; 534 535 lock_mode = xfs_ilock_attr_map_shared(dp); 536 error = xfs_attr_list_ilocked(context); 537 xfs_iunlock(dp, lock_mode); 538 return error; 539 } 540