| | 1 | // SPDX-License-Identifier: GPL-2.0 |
| | 2 | /* |
| | 3 | * linux/fs/isofs/rock.c |
| | 4 | * |
| | 5 | * (C) 1992, 1993 Eric Youngdale |
| | 6 | * |
| | 7 | * Rock Ridge Extensions to iso9660 |
| | 8 | */ |
| | 9 | |
| | 10 | #include <linux/slab.h> |
| | 11 | #include <linux/pagemap.h> |
| | 12 | |
| | 13 | #include "isofs.h" |
| | 14 | #include "rock.h" |
| | 15 | |
| | 16 | /* |
| | 17 | * These functions are designed to read the system areas of a directory record |
| | 18 | * and extract relevant information. There are different functions provided |
| | 19 | * depending upon what information we need at the time. One function fills |
| | 20 | * out an inode structure, a second one extracts a filename, a third one |
| | 21 | * returns a symbolic link name, and a fourth one returns the extent number |
| | 22 | * for the file. |
| | 23 | */ |
| | 24 | |
| | 25 | #define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */ |
| | 26 | |
| | 27 | struct rock_state { |
| | 28 | void *buffer; |
| | 29 | unsigned char *chr; |
| | 30 | int len; |
| | 31 | int cont_size; |
| | 32 | int cont_extent; |
| | 33 | int cont_offset; |
| | 34 | int cont_loops; |
| | 35 | struct inode *inode; |
| | 36 | }; |
| | 37 | |
| | 38 | /* |
| | 39 | * This is a way of ensuring that we have something in the system |
| | 40 | * use fields that is compatible with Rock Ridge. Return zero on success. |
| | 41 | */ |
| | 42 | |
| | 43 | static int check_sp(struct rock_ridge *rr, struct inode *inode) |
| | 44 | { |
| | 45 | if (rr->u.SP.magic[0] != 0xbe) |
| | 46 | return -1; |
| | 47 | if (rr->u.SP.magic[1] != 0xef) |
| | 48 | return -1; |
| | 49 | ISOFS_SB(inode->i_sb)->s_rock_offset = rr->u.SP.skip; |
| | 50 | return 0; |
| | 51 | } |
| | 52 | |
| | 53 | static void setup_rock_ridge(struct iso_directory_record *de, |
| | 54 | struct inode *inode, struct rock_state *rs) |
| | 55 | { |
| | 56 | rs->len = sizeof(struct iso_directory_record) + de->name_len[0]; |
| | 57 | if (rs->len & 1) |
| | 58 | (rs->len)++; |
| | 59 | rs->chr = (unsigned char *)de + rs->len; |
| | 60 | rs->len = *((unsigned char *)de) - rs->len; |
| | 61 | if (rs->len < 0) |
| | 62 | rs->len = 0; |
| | 63 | |
| | 64 | if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) { |
| | 65 | rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset; |
| | 66 | rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset; |
| | 67 | if (rs->len < 0) |
| | 68 | rs->len = 0; |
| | 69 | } |
| | 70 | } |
| | 71 | |
| | 72 | static void init_rock_state(struct rock_state *rs, struct inode *inode) |
| | 73 | { |
| | 74 | memset(rs, 0, sizeof(*rs)); |
| | 75 | rs->inode = inode; |
| | 76 | } |
| | 77 | |
| | 78 | /* Maximum number of Rock Ridge continuation entries */ |
| | 79 | #define RR_MAX_CE_ENTRIES 32 |
| | 80 | |
| | 81 | /* |
| | 82 | * Returns 0 if the caller should continue scanning, 1 if the scan must end |
| | 83 | * and -ve on error. |
| | 84 | */ |
| | 85 | static int rock_continue(struct rock_state *rs) |
| | 86 | { |
| | 87 | int ret = 1; |
| | 88 | int blocksize = 1 << rs->inode->i_blkbits; |
| | 89 | const int min_de_size = offsetof(struct rock_ridge, u); |
| | 90 | |
| | 91 | kfree(rs->buffer); |
| | 92 | rs->buffer = NULL; |
| | 93 | |
| | 94 | if ((unsigned)rs->cont_offset > blocksize - min_de_size || |
| | 95 | (unsigned)rs->cont_size > blocksize || |
| | 96 | (unsigned)(rs->cont_offset + rs->cont_size) > blocksize) { |
| | 97 | printk(KERN_NOTICE "rock: corrupted directory entry. " |
| | 98 | "extent=%d, offset=%d, size=%d\n", |
| | 99 | rs->cont_extent, rs->cont_offset, rs->cont_size); |
| | 100 | ret = -EIO; |
| | 101 | goto out; |
| | 102 | } |
| | 103 | |
| | 104 | if (rs->cont_extent) { |
| | 105 | struct buffer_head *bh; |
| | 106 | |
| | 107 | rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL); |
| | 108 | if (!rs->buffer) { |
| | 109 | ret = -ENOMEM; |
| | 110 | goto out; |
| | 111 | } |
| | 112 | ret = -EIO; |
| | 113 | if (++rs->cont_loops >= RR_MAX_CE_ENTRIES) |
| | 114 | goto out; |
| | 115 | bh = sb_bread(rs->inode->i_sb, rs->cont_extent); |
| | 116 | if (bh) { |
| | 117 | memcpy(rs->buffer, bh->b_data + rs->cont_offset, |
| | 118 | rs->cont_size); |
| | 119 | put_bh(bh); |
| | 120 | rs->chr = rs->buffer; |
| | 121 | rs->len = rs->cont_size; |
| | 122 | rs->cont_extent = 0; |
| | 123 | rs->cont_size = 0; |
| | 124 | rs->cont_offset = 0; |
| | 125 | return 0; |
| | 126 | } |
| | 127 | printk("Unable to read rock-ridge attributes\n"); |
| | 128 | } |
| | 129 | out: |
| | 130 | kfree(rs->buffer); |
| | 131 | rs->buffer = NULL; |
| | 132 | return ret; |
| | 133 | } |
| | 134 | |
| | 135 | /* |
| | 136 | * We think there's a record of type `sig' at rs->chr. Parse the signature |
| | 137 | * and make sure that there's really room for a record of that type. |
| | 138 | */ |
| | 139 | static int rock_check_overflow(struct rock_state *rs, int sig) |
| | 140 | { |
| | 141 | int len; |
| | 142 | |
| | 143 | switch (sig) { |
| | 144 | case SIG('S', 'P'): |
| | 145 | len = sizeof(struct SU_SP_s); |
| | 146 | break; |
| | 147 | case SIG('C', 'E'): |
| | 148 | len = sizeof(struct SU_CE_s); |
| | 149 | break; |
| | 150 | case SIG('E', 'R'): |
| | 151 | len = sizeof(struct SU_ER_s); |
| | 152 | break; |
| | 153 | case SIG('R', 'R'): |
| | 154 | len = sizeof(struct RR_RR_s); |
| | 155 | break; |
| | 156 | case SIG('P', 'X'): |
| | 157 | len = sizeof(struct RR_PX_s); |
| | 158 | break; |
| | 159 | case SIG('P', 'N'): |
| | 160 | len = sizeof(struct RR_PN_s); |
| | 161 | break; |
| | 162 | case SIG('S', 'L'): |
| | 163 | len = sizeof(struct RR_SL_s); |
| | 164 | break; |
| | 165 | case SIG('N', 'M'): |
| | 166 | len = sizeof(struct RR_NM_s); |
| | 167 | break; |
| | 168 | case SIG('C', 'L'): |
| | 169 | len = sizeof(struct RR_CL_s); |
| | 170 | break; |
| | 171 | case SIG('P', 'L'): |
| | 172 | len = sizeof(struct RR_PL_s); |
| | 173 | break; |
| | 174 | case SIG('T', 'F'): |
| | 175 | len = sizeof(struct RR_TF_s); |
| | 176 | break; |
| | 177 | case SIG('Z', 'F'): |
| | 178 | len = sizeof(struct RR_ZF_s); |
| | 179 | break; |
| | 180 | default: |
| | 181 | len = 0; |
| | 182 | break; |
| | 183 | } |
| | 184 | len += offsetof(struct rock_ridge, u); |
| | 185 | if (len > rs->len) { |
| | 186 | printk(KERN_NOTICE "rock: directory entry would overflow " |
| | 187 | "storage\n"); |
| | 188 | printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n", |
| | 189 | sig, len, rs->len); |
| | 190 | return -EIO; |
| | 191 | } |
| | 192 | return 0; |
| | 193 | } |
| | 194 | |
| | 195 | /* |
| | 196 | * return length of name field; 0: not found, -1: to be ignored |
| | 197 | */ |
| | 198 | int get_rock_ridge_filename(struct iso_directory_record *de, |
| | 199 | char *retname, struct inode *inode) |
| | 200 | { |
| | 201 | struct rock_state rs; |
| | 202 | struct rock_ridge *rr; |
| | 203 | int sig; |
| | 204 | int retnamlen = 0; |
| | 205 | int truncate = 0; |
| | 206 | int ret = 0; |
| | 207 | char *p; |
| | 208 | int len; |
| | 209 | |
| | 210 | if (!ISOFS_SB(inode->i_sb)->s_rock) |
| | 211 | return 0; |
| | 212 | *retname = 0; |
| | 213 | |
| | 214 | init_rock_state(&rs, inode); |
| | 215 | setup_rock_ridge(de, inode, &rs); |
| | 216 | repeat: |
| | 217 | |
| | 218 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
| | 219 | rr = (struct rock_ridge *)rs.chr; |
| | 220 | /* |
| | 221 | * Ignore rock ridge info if rr->len is out of range, but |
| | 222 | * don't return -EIO because that would make the file |
| | 223 | * invisible. |
| | 224 | */ |
| | 225 | if (rr->len < 3) |
| | 226 | goto out; /* Something got screwed up here */ |
| | 227 | sig = isonum_721(rs.chr); |
| | 228 | if (rock_check_overflow(&rs, sig)) |
| | 229 | goto eio; |
| | 230 | rs.chr += rr->len; |
| | 231 | rs.len -= rr->len; |
| | 232 | /* |
| | 233 | * As above, just ignore the rock ridge info if rr->len |
| | 234 | * is bogus. |
| | 235 | */ |
| | 236 | if (rs.len < 0) |
| | 237 | goto out; /* Something got screwed up here */ |
| | 238 | |
| | 239 | switch (sig) { |
| | 240 | case SIG('R', 'R'): |
| | 241 | if ((rr->u.RR.flags[0] & RR_NM) == 0) |
| | 242 | goto out; |
| | 243 | break; |
| | 244 | case SIG('S', 'P'): |
| | 245 | if (check_sp(rr, inode)) |
| | 246 | goto out; |
| | 247 | break; |
| | 248 | case SIG('C', 'E'): |
| | 249 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
| | 250 | rs.cont_offset = isonum_733(rr->u.CE.offset); |
| | 251 | rs.cont_size = isonum_733(rr->u.CE.size); |
| | 252 | break; |
| | 253 | case SIG('N', 'M'): |
| | 254 | if (truncate) |
| | 255 | break; |
| | 256 | if (rr->len < 5) |
| | 257 | break; |
| | 258 | /* |
| | 259 | * If the flags are 2 or 4, this indicates '.' or '..'. |
| | 260 | * We don't want to do anything with this, because it |
| | 261 | * screws up the code that calls us. We don't really |
| | 262 | * care anyways, since we can just use the non-RR |
| | 263 | * name. |
| | 264 | */ |
| | 265 | if (rr->u.NM.flags & 6) |
| | 266 | break; |
| | 267 | |
| | 268 | if (rr->u.NM.flags & ~1) { |
| | 269 | printk("Unsupported NM flag settings (%d)\n", |
| | 270 | rr->u.NM.flags); |
| | 271 | break; |
| | 272 | } |
| | 273 | len = rr->len - 5; |
| | 274 | if (retnamlen + len >= 254) { |
| | 275 | truncate = 1; |
| | 276 | break; |
| | 277 | } |
| | 278 | p = memchr(rr->u.NM.name, '\0', len); |
| | 279 | if (unlikely(p)) |
| | 280 | len = p - rr->u.NM.name; |
| | 281 | memcpy(retname + retnamlen, rr->u.NM.name, len); |
| | 282 | retnamlen += len; |
| | 283 | retname[retnamlen] = '\0'; |
| | 284 | break; |
| | 285 | case SIG('R', 'E'): |
| | 286 | kfree(rs.buffer); |
| | 287 | return -1; |
| | 288 | default: |
| | 289 | break; |
| | 290 | } |
| | 291 | } |
| | 292 | ret = rock_continue(&rs); |
| | 293 | if (ret == 0) |
| | 294 | goto repeat; |
| | 295 | if (ret == 1) |
| | 296 | return retnamlen; /* If 0, this file did not have a NM field */ |
| | 297 | out: |
| | 298 | kfree(rs.buffer); |
| | 299 | return ret; |
| | 300 | eio: |
| | 301 | ret = -EIO; |
| | 302 | goto out; |
| | 303 | } |
| | 304 | |
| | 305 | #define RR_REGARD_XA 1 |
| | 306 | #define RR_RELOC_DE 2 |
| | 307 | |
| | 308 | static int |
| | 309 | parse_rock_ridge_inode_internal(struct iso_directory_record *de, |
| | 310 | struct inode *inode, int flags) |
| | 311 | { |
| | 312 | int symlink_len = 0; |
| | 313 | int cnt, sig; |
| | 314 | unsigned int reloc_block; |
| | 315 | struct inode *reloc; |
| | 316 | struct rock_ridge *rr; |
| | 317 | int rootflag; |
| | 318 | struct rock_state rs; |
| | 319 | int ret = 0; |
| | 320 | |
| | 321 | if (!ISOFS_SB(inode->i_sb)->s_rock) |
| | 322 | return 0; |
| | 323 | |
| | 324 | init_rock_state(&rs, inode); |
| | 325 | setup_rock_ridge(de, inode, &rs); |
| | 326 | if (flags & RR_REGARD_XA) { |
| | 327 | rs.chr += 14; |
| | 328 | rs.len -= 14; |
| | 329 | if (rs.len < 0) |
| | 330 | rs.len = 0; |
| | 331 | } |
| | 332 | |
| | 333 | repeat: |
| | 334 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
| | 335 | rr = (struct rock_ridge *)rs.chr; |
| | 336 | /* |
| | 337 | * Ignore rock ridge info if rr->len is out of range, but |
| | 338 | * don't return -EIO because that would make the file |
| | 339 | * invisible. |
| | 340 | */ |
| | 341 | if (rr->len < 3) |
| | 342 | goto out; /* Something got screwed up here */ |
| | 343 | sig = isonum_721(rs.chr); |
| | 344 | if (rock_check_overflow(&rs, sig)) |
| | 345 | goto eio; |
| | 346 | rs.chr += rr->len; |
| | 347 | rs.len -= rr->len; |
| | 348 | /* |
| | 349 | * As above, just ignore the rock ridge info if rr->len |
| | 350 | * is bogus. |
| | 351 | */ |
| | 352 | if (rs.len < 0) |
| | 353 | goto out; /* Something got screwed up here */ |
| | 354 | |
| | 355 | switch (sig) { |
| | 356 | #ifndef CONFIG_ZISOFS /* No flag for SF or ZF */ |
| | 357 | case SIG('R', 'R'): |
| | 358 | if ((rr->u.RR.flags[0] & |
| | 359 | (RR_PX | RR_TF | RR_SL | RR_CL)) == 0) |
| | 360 | goto out; |
| | 361 | break; |
| | 362 | #endif |
| | 363 | case SIG('S', 'P'): |
| | 364 | if (check_sp(rr, inode)) |
| | 365 | goto out; |
| | 366 | break; |
| | 367 | case SIG('C', 'E'): |
| | 368 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
| | 369 | rs.cont_offset = isonum_733(rr->u.CE.offset); |
| | 370 | rs.cont_size = isonum_733(rr->u.CE.size); |
| | 371 | break; |
| | 372 | case SIG('E', 'R'): |
| | 373 | /* Invalid length of ER tag id? */ |
| | 374 | if (rr->u.ER.len_id + offsetof(struct rock_ridge, u.ER.data) > rr->len) |
| | 375 | goto out; |
| | 376 | ISOFS_SB(inode->i_sb)->s_rock = 1; |
| | 377 | printk(KERN_DEBUG "ISO 9660 Extensions: "); |
| | 378 | { |
| | 379 | int p; |
| | 380 | for (p = 0; p < rr->u.ER.len_id; p++) |
| | 381 | printk(KERN_CONT "%c", rr->u.ER.data[p]); |
| | 382 | } |
| | 383 | printk(KERN_CONT "\n"); |
| | 384 | break; |
| | 385 | case SIG('P', 'X'): |
| | 386 | inode->i_mode = isonum_733(rr->u.PX.mode); |
| | 387 | set_nlink(inode, isonum_733(rr->u.PX.n_links)); |
| | 388 | i_uid_write(inode, isonum_733(rr->u.PX.uid)); |
| | 389 | i_gid_write(inode, isonum_733(rr->u.PX.gid)); |
| | 390 | break; |
| | 391 | case SIG('P', 'N'): |
| | 392 | { |
| | 393 | int high, low; |
| | 394 | high = isonum_733(rr->u.PN.dev_high); |
| | 395 | low = isonum_733(rr->u.PN.dev_low); |
| | 396 | /* |
| | 397 | * The Rock Ridge standard specifies that if |
| | 398 | * sizeof(dev_t) <= 4, then the high field is |
| | 399 | * unused, and the device number is completely |
| | 400 | * stored in the low field. Some writers may |
| | 401 | * ignore this subtlety, |
| | 402 | * and as a result we test to see if the entire |
| | 403 | * device number is |
| | 404 | * stored in the low field, and use that. |
| | 405 | */ |
| | 406 | if ((low & ~0xff) && high == 0) { |
| | 407 | inode->i_rdev = |
| | 408 | MKDEV(low >> 8, low & 0xff); |
| | 409 | } else { |
| | 410 | inode->i_rdev = |
| | 411 | MKDEV(high, low); |
| | 412 | } |
| | 413 | } |
| | 414 | break; |
| | 415 | case SIG('T', 'F'): |
| | 416 | /* |
| | 417 | * Some RRIP writers incorrectly place ctime in the |
| | 418 | * TF_CREATE field. Try to handle this correctly for |
| | 419 | * either case. |
| | 420 | */ |
| | 421 | /* Rock ridge never appears on a High Sierra disk */ |
| | 422 | cnt = 0; |
| | 423 | if (rr->u.TF.flags & TF_CREATE) { |
| | 424 | inode->i_ctime.tv_sec = |
| | 425 | iso_date(rr->u.TF.times[cnt++].time, |
| | 426 | 0); |
| | 427 | inode->i_ctime.tv_nsec = 0; |
| | 428 | } |
| | 429 | if (rr->u.TF.flags & TF_MODIFY) { |
| | 430 | inode->i_mtime.tv_sec = |
| | 431 | iso_date(rr->u.TF.times[cnt++].time, |
| | 432 | 0); |
| | 433 | inode->i_mtime.tv_nsec = 0; |
| | 434 | } |
| | 435 | if (rr->u.TF.flags & TF_ACCESS) { |
| | 436 | inode->i_atime.tv_sec = |
| | 437 | iso_date(rr->u.TF.times[cnt++].time, |
| | 438 | 0); |
| | 439 | inode->i_atime.tv_nsec = 0; |
| | 440 | } |
| | 441 | if (rr->u.TF.flags & TF_ATTRIBUTES) { |
| | 442 | inode->i_ctime.tv_sec = |
| | 443 | iso_date(rr->u.TF.times[cnt++].time, |
| | 444 | 0); |
| | 445 | inode->i_ctime.tv_nsec = 0; |
| | 446 | } |
| | 447 | break; |
| | 448 | case SIG('S', 'L'): |
| | 449 | { |
| | 450 | int slen; |
| | 451 | struct SL_component *slp; |
| | 452 | struct SL_component *oldslp; |
| | 453 | slen = rr->len - 5; |
| | 454 | slp = &rr->u.SL.link; |
| | 455 | inode->i_size = symlink_len; |
| | 456 | while (slen > 1) { |
| | 457 | rootflag = 0; |
| | 458 | switch (slp->flags & ~1) { |
| | 459 | case 0: |
| | 460 | inode->i_size += |
| | 461 | slp->len; |
| | 462 | break; |
| | 463 | case 2: |
| | 464 | inode->i_size += 1; |
| | 465 | break; |
| | 466 | case 4: |
| | 467 | inode->i_size += 2; |
| | 468 | break; |
| | 469 | case 8: |
| | 470 | rootflag = 1; |
| | 471 | inode->i_size += 1; |
| | 472 | break; |
| | 473 | default: |
| | 474 | printk("Symlink component flag " |
| | 475 | "not implemented\n"); |
| | 476 | } |
| | 477 | slen -= slp->len + 2; |
| | 478 | oldslp = slp; |
| | 479 | slp = (struct SL_component *) |
| | 480 | (((char *)slp) + slp->len + 2); |
| | 481 | |
| | 482 | if (slen < 2) { |
| | 483 | if (((rr->u.SL. |
| | 484 | flags & 1) != 0) |
| | 485 | && |
| | 486 | ((oldslp-> |
| | 487 | flags & 1) == 0)) |
| | 488 | inode->i_size += |
| | 489 | 1; |
| | 490 | break; |
| | 491 | } |
| | 492 | |
| | 493 | /* |
| | 494 | * If this component record isn't |
| | 495 | * continued, then append a '/'. |
| | 496 | */ |
| | 497 | if (!rootflag |
| | 498 | && (oldslp->flags & 1) == 0) |
| | 499 | inode->i_size += 1; |
| | 500 | } |
| | 501 | } |
| | 502 | symlink_len = inode->i_size; |
| | 503 | break; |
| | 504 | case SIG('R', 'E'): |
| | 505 | printk(KERN_WARNING "Attempt to read inode for " |
| | 506 | "relocated directory\n"); |
| | 507 | goto out; |
| | 508 | case SIG('C', 'L'): |
| | 509 | if (flags & RR_RELOC_DE) { |
| | 510 | printk(KERN_ERR |
| | 511 | "ISOFS: Recursive directory relocation " |
| | 512 | "is not supported\n"); |
| | 513 | goto eio; |
| | 514 | } |
| | 515 | reloc_block = isonum_733(rr->u.CL.location); |
| | 516 | if (reloc_block == ISOFS_I(inode)->i_iget5_block && |
| | 517 | ISOFS_I(inode)->i_iget5_offset == 0) { |
| | 518 | printk(KERN_ERR |
| | 519 | "ISOFS: Directory relocation points to " |
| | 520 | "itself\n"); |
| | 521 | goto eio; |
| | 522 | } |
| | 523 | ISOFS_I(inode)->i_first_extent = reloc_block; |
| | 524 | reloc = isofs_iget_reloc(inode->i_sb, reloc_block, 0); |
| | 525 | if (IS_ERR(reloc)) { |
| | 526 | ret = PTR_ERR(reloc); |
| | 527 | goto out; |
| | 528 | } |
| | 529 | inode->i_mode = reloc->i_mode; |
| | 530 | set_nlink(inode, reloc->i_nlink); |
| | 531 | inode->i_uid = reloc->i_uid; |
| | 532 | inode->i_gid = reloc->i_gid; |
| | 533 | inode->i_rdev = reloc->i_rdev; |
| | 534 | inode->i_size = reloc->i_size; |
| | 535 | inode->i_blocks = reloc->i_blocks; |
| | 536 | inode->i_atime = reloc->i_atime; |
| | 537 | inode->i_ctime = reloc->i_ctime; |
| | 538 | inode->i_mtime = reloc->i_mtime; |
| | 539 | iput(reloc); |
| | 540 | break; |
| | 541 | #ifdef CONFIG_ZISOFS |
| | 542 | case SIG('Z', 'F'): { |
| | 543 | int algo; |
| | 544 | |
| | 545 | if (ISOFS_SB(inode->i_sb)->s_nocompress) |
| | 546 | break; |
| | 547 | algo = isonum_721(rr->u.ZF.algorithm); |
| | 548 | if (algo == SIG('p', 'z')) { |
| | 549 | int block_shift = |
| | 550 | isonum_711(&rr->u.ZF.parms[1]); |
| | 551 | if (block_shift > 17) { |
| | 552 | printk(KERN_WARNING "isofs: " |
| | 553 | "Can't handle ZF block " |
| | 554 | "size of 2^%d\n", |
| | 555 | block_shift); |
| | 556 | } else { |
| | 557 | /* |
| | 558 | * Note: we don't change |
| | 559 | * i_blocks here |
| | 560 | */ |
| | 561 | ISOFS_I(inode)->i_file_format = |
| | 562 | isofs_file_compressed; |
| | 563 | /* |
| | 564 | * Parameters to compression |
| | 565 | * algorithm (header size, |
| | 566 | * block size) |
| | 567 | */ |
| | 568 | ISOFS_I(inode)->i_format_parm[0] = |
| | 569 | isonum_711(&rr->u.ZF.parms[0]); |
| | 570 | ISOFS_I(inode)->i_format_parm[1] = |
| | 571 | isonum_711(&rr->u.ZF.parms[1]); |
| | 572 | inode->i_size = |
| | 573 | isonum_733(rr->u.ZF. |
| | 574 | real_size); |
| | 575 | } |
| | 576 | } else { |
| | 577 | printk(KERN_WARNING |
| | 578 | "isofs: Unknown ZF compression " |
| | 579 | "algorithm: %c%c\n", |
| | 580 | rr->u.ZF.algorithm[0], |
| | 581 | rr->u.ZF.algorithm[1]); |
| | 582 | } |
| | 583 | break; |
| | 584 | } |
| | 585 | #endif |
| | 586 | default: |
| | 587 | break; |
| | 588 | } |
| | 589 | } |
| | 590 | ret = rock_continue(&rs); |
| | 591 | if (ret == 0) |
| | 592 | goto repeat; |
| | 593 | if (ret == 1) |
| | 594 | ret = 0; |
| | 595 | out: |
| | 596 | kfree(rs.buffer); |
| | 597 | return ret; |
| | 598 | eio: |
| | 599 | ret = -EIO; |
| | 600 | goto out; |
| | 601 | } |
| | 602 | |
| | 603 | static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit) |
| | 604 | { |
| | 605 | int slen; |
| | 606 | int rootflag; |
| | 607 | struct SL_component *oldslp; |
| | 608 | struct SL_component *slp; |
| | 609 | slen = rr->len - 5; |
| | 610 | slp = &rr->u.SL.link; |
| | 611 | while (slen > 1) { |
| | 612 | rootflag = 0; |
| | 613 | switch (slp->flags & ~1) { |
| | 614 | case 0: |
| | 615 | if (slp->len > plimit - rpnt) |
| | 616 | return NULL; |
| | 617 | memcpy(rpnt, slp->text, slp->len); |
| | 618 | rpnt += slp->len; |
| | 619 | break; |
| | 620 | case 2: |
| | 621 | if (rpnt >= plimit) |
| | 622 | return NULL; |
| | 623 | *rpnt++ = '.'; |
| | 624 | break; |
| | 625 | case 4: |
| | 626 | if (2 > plimit - rpnt) |
| | 627 | return NULL; |
| | 628 | *rpnt++ = '.'; |
| | 629 | *rpnt++ = '.'; |
| | 630 | break; |
| | 631 | case 8: |
| | 632 | if (rpnt >= plimit) |
| | 633 | return NULL; |
| | 634 | rootflag = 1; |
| | 635 | *rpnt++ = '/'; |
| | 636 | break; |
| | 637 | default: |
| | 638 | printk("Symlink component flag not implemented (%d)\n", |
| | 639 | slp->flags); |
| | 640 | } |
| | 641 | slen -= slp->len + 2; |
| | 642 | oldslp = slp; |
| | 643 | slp = (struct SL_component *)((char *)slp + slp->len + 2); |
| | 644 | |
| | 645 | if (slen < 2) { |
| | 646 | /* |
| | 647 | * If there is another SL record, and this component |
| | 648 | * record isn't continued, then add a slash. |
| | 649 | */ |
| | 650 | if ((!rootflag) && (rr->u.SL.flags & 1) && |
| | 651 | !(oldslp->flags & 1)) { |
| | 652 | if (rpnt >= plimit) |
| | 653 | return NULL; |
| | 654 | *rpnt++ = '/'; |
| | 655 | } |
| | 656 | break; |
| | 657 | } |
| | 658 | |
| | 659 | /* |
| | 660 | * If this component record isn't continued, then append a '/'. |
| | 661 | */ |
| | 662 | if (!rootflag && !(oldslp->flags & 1)) { |
| | 663 | if (rpnt >= plimit) |
| | 664 | return NULL; |
| | 665 | *rpnt++ = '/'; |
| | 666 | } |
| | 667 | } |
| | 668 | return rpnt; |
| | 669 | } |
| | 670 | |
| | 671 | int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode, |
| | 672 | int relocated) |
| | 673 | { |
| | 674 | int flags = relocated ? RR_RELOC_DE : 0; |
| | 675 | int result = parse_rock_ridge_inode_internal(de, inode, flags); |
| | 676 | |
| | 677 | /* |
| | 678 | * if rockridge flag was reset and we didn't look for attributes |
| | 679 | * behind eventual XA attributes, have a look there |
| | 680 | */ |
| | 681 | if ((ISOFS_SB(inode->i_sb)->s_rock_offset == -1) |
| | 682 | && (ISOFS_SB(inode->i_sb)->s_rock == 2)) { |
| | 683 | result = parse_rock_ridge_inode_internal(de, inode, |
| | 684 | flags | RR_REGARD_XA); |
| | 685 | } |
| | 686 | return result; |
| | 687 | } |
| | 688 | |
| | 689 | /* |
| | 690 | * readpage() for symlinks: reads symlink contents into the page and either |
| | 691 | * makes it uptodate and returns 0 or returns error (-EIO) |
| | 692 | */ |
| | 693 | static int rock_ridge_symlink_readpage(struct file *file, struct page *page) |
| | 694 | { |
| | 695 | struct inode *inode = page->mapping->host; |
| | 696 | struct iso_inode_info *ei = ISOFS_I(inode); |
| | 697 | struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); |
| | 698 | char *link = page_address(page); |
| | 699 | unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); |
| | 700 | struct buffer_head *bh; |
| | 701 | char *rpnt = link; |
| | 702 | unsigned char *pnt; |
| | 703 | struct iso_directory_record *raw_de; |
| | 704 | unsigned long block, offset; |
| | 705 | int sig; |
| | 706 | struct rock_ridge *rr; |
| | 707 | struct rock_state rs; |
| | 708 | int ret; |
| | 709 | |
| | 710 | if (!sbi->s_rock) |
| | 711 | goto error; |
| | 712 | |
| | 713 | init_rock_state(&rs, inode); |
| | 714 | block = ei->i_iget5_block; |
| | 715 | bh = sb_bread(inode->i_sb, block); |
| | 716 | if (!bh) |
| | 717 | goto out_noread; |
| | 718 | |
| | 719 | offset = ei->i_iget5_offset; |
| | 720 | pnt = (unsigned char *)bh->b_data + offset; |
| | 721 | |
| | 722 | raw_de = (struct iso_directory_record *)pnt; |
| | 723 | |
| | 724 | /* |
| | 725 | * If we go past the end of the buffer, there is some sort of error. |
| | 726 | */ |
| | 727 | if (offset + *pnt > bufsize) |
| | 728 | goto out_bad_span; |
| | 729 | |
| | 730 | /* |
| | 731 | * Now test for possible Rock Ridge extensions which will override |
| | 732 | * some of these numbers in the inode structure. |
| | 733 | */ |
| | 734 | |
| | 735 | setup_rock_ridge(raw_de, inode, &rs); |
| | 736 | |
| | 737 | repeat: |
| | 738 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
| | 739 | rr = (struct rock_ridge *)rs.chr; |
| | 740 | if (rr->len < 3) |
| | 741 | goto out; /* Something got screwed up here */ |
| | 742 | sig = isonum_721(rs.chr); |
| | 743 | if (rock_check_overflow(&rs, sig)) |
| | 744 | goto out; |
| | 745 | rs.chr += rr->len; |
| | 746 | rs.len -= rr->len; |
| | 747 | if (rs.len < 0) |
| | 748 | goto out; /* corrupted isofs */ |
| | 749 | |
| | 750 | switch (sig) { |
| | 751 | case SIG('R', 'R'): |
| | 752 | if ((rr->u.RR.flags[0] & RR_SL) == 0) |
| | 753 | goto out; |
| | 754 | break; |
| | 755 | case SIG('S', 'P'): |
| | 756 | if (check_sp(rr, inode)) |
| | 757 | goto out; |
| | 758 | break; |
| | 759 | case SIG('S', 'L'): |
| | 760 | rpnt = get_symlink_chunk(rpnt, rr, |
| | 761 | link + (PAGE_SIZE - 1)); |
| | 762 | if (rpnt == NULL) |
| | 763 | goto out; |
| | 764 | break; |
| | 765 | case SIG('C', 'E'): |
| | 766 | /* This tells is if there is a continuation record */ |
| | 767 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
| | 768 | rs.cont_offset = isonum_733(rr->u.CE.offset); |
| | 769 | rs.cont_size = isonum_733(rr->u.CE.size); |
| | 770 | default: |
| | 771 | break; |
| | 772 | } |
| | 773 | } |
| | 774 | ret = rock_continue(&rs); |
| | 775 | if (ret == 0) |
| | 776 | goto repeat; |
| | 777 | if (ret < 0) |
| | 778 | goto fail; |
| | 779 | |
| | 780 | if (rpnt == link) |
| | 781 | goto fail; |
| | 782 | brelse(bh); |
| | 783 | *rpnt = '\0'; |
| | 784 | SetPageUptodate(page); |
| | 785 | unlock_page(page); |
| | 786 | return 0; |
| | 787 | |
| | 788 | /* error exit from macro */ |
| | 789 | out: |
| | 790 | kfree(rs.buffer); |
| | 791 | goto fail; |
| | 792 | out_noread: |
| | 793 | printk("unable to read i-node block"); |
| | 794 | goto fail; |
| | 795 | out_bad_span: |
| | 796 | printk("symlink spans iso9660 blocks\n"); |
| | 797 | fail: |
| | 798 | brelse(bh); |
| | 799 | error: |
| | 800 | SetPageError(page); |
| | 801 | unlock_page(page); |
| | 802 | return -EIO; |
| | 803 | } |
| | 804 | |
| | 805 | const struct address_space_operations isofs_symlink_aops = { |
| | 806 | .readpage = rock_ridge_symlink_readpage |
| | 807 | }; |
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / blame_incremental