Bug#1121430: syslinux: Mismatch between the main and the backup boot sector in FAT32
Package: syslinux
Version: 3:6.04~git20190206.bf6db5b4+dfsg1-3.1
Severity: normal
Dear Maintainer,
when you install syslinux on a FAT32 filesystem it updates the main
boot sector but not the backup boot sector (A_BF_BPB_BkUpBootSec).
If you run fsck after that it will detect the mismatch and ask what
boot sector to keep. This can only be fixed in interactive mode since
the fsck tool has no way to know the right answer and selecting
the wrong one can make the disk unbootable. The end user does not
necessarily know what's going on either.
This is very easy to reproduce (note the '-F 32' option, this does not
happen with FAT16):
fallocate -l 100M disk.img
mkfs.vfat -F 32 -I disk.img
dosfsck disk.img
syslinux disk.img
dosfsck disk.img
The first dosfsck succeeds but the second one shows the problem:
$ dosfsck disk.img
fsck.fat 4.2 (2021-01-31)
There are differences between boot sector and its backup.
This is mostly harmless. Differences: (offset:original/backup)
3:53/6d, 4:59/6b, 5:53/66, 6:4c/73, 7:49/2e, 8:4e/66, 9:55/61, 10:58/74
, 90:fa/0e, 91:fc/1f, 92:31/be, 93:c9/77, 94:8e/7c, 95:d1/ac, 96:bc/22
, 97:76/c0, 98:7b/74, 99:52/0b, 100:06/56, 101:57/b4, 102:1e/0e, 103:56/bb
, 104:8e/07, 105:c1/00, 106:b1/cd, 107:26/10, 108:bf/5e, 109:78/eb
, 110:7b/f0, 111:f3/32, 112:a5/e4, 113:8e/cd, 114:d9/16, 115:bb/cd
, 116:78/19, 117:00/eb, 118:0f/fe, 119:b4/54, 120:37/68, 121:0f/69
, 122:a0/73, 123:56/20, 124:20/69, 125:d2/73, 126:78/20, 127:1b/6e
, 128:31/6f, 129:c0/74, 130:b1/20, 131:06/61, 132:89/20, 133:3f/62
, 134:89/6f, 135:47/6f, 136:02/74, 137:f3/61, 138:64/62, 139:a5/6c
, 140:8a/65, 141:0e/20, 142:18/64, 143:7c/69, 144:88/73, 145:4d/6b
, 146:f8/2e, 147:50/20, 148:50/20, 150:50/6c, 151:cd/65, 152:13/61
, 153:eb/73, 154:62/65, 155:8b/20, 156:55/69, 157:aa/6e, 158:8b/73
, 159:75/65, 160:a8/72, 161:c1/74, 162:ee/20, 163:04/61, 164:01/20
, 165:f2/62, 166:83/6f, 167:fa/6f, 168:4f/74, 169:76/61, 170:31/62
, 171:81/6c, 172:fa/65, 173:b2/20, 174:07/66, 175:73/6c, 176:2b/6f
, 177:f6/70, 178:45/70, 179:b4/79, 180:7f/20, 181:75/61, 182:25/6e
, 183:38/64, 184:4d/0d, 185:b8/0a, 186:74/70, 187:20/72, 188:66/65
, 189:3d/73, 190:21/73, 191:47/20, 192:50/61, 193:54/6e, 194:75/79
, 195:10/20, 196:80/6b, 197:7d/65, 198:b8/79, 199:ed/20, 200:75/74
, 201:0a/6f, 202:66/20, 203:ff/74, 204:75/72, 205:ec/79, 206:66/20
, 207:ff/61, 208:75/67, 209:e8/61, 210:eb/69, 211:0f/6e, 212:51/20
, 213:51/2e, 214:66/2e, 215:ff/2e, 216:75/20, 217:bc/0d, 218:eb/0a
, 219:07/00, 220:51/00, 221:51/00, 222:66/00, 223:ff/00, 224:36/00
, 225:1c/00, 226:7c/00, 227:b4/00, 228:08/00, 229:e8/00, 230:e9/00
, 232:72/00, 233:13/00, 234:20/00, 235:e4/00, 236:75/00, 237:0f/00
, 238:c1/00, 239:ea/00, 240:08/00, 241:42/00, 242:89/00, 243:16/00
, 244:1a/00, 245:7c/00, 246:83/00, 247:e1/00, 248:3f/00, 249:89/00
, 250:0e/00, 251:18/00, 252:7c/00, 253:fb/00, 254:bb/00, 255:aa/00
, 256:55/00, 257:b4/00, 258:41/00, 259:e8/00, 260:cb/00, 262:72/00
, 263:10/00, 264:81/00, 265:fb/00, 266:55/00, 267:aa/00, 268:75/00
, 269:0a/00, 270:f6/00, 271:c1/00, 272:01/00, 273:74/00, 274:05/00
, 275:c6/00, 276:06/00, 277:46/00, 278:7d/00, 280:66/00, 281:b8/00
, 282:71/00, 283:0c/00, 286:66/00, 287:ba/00, 292:bb/00, 294:80/00
, 295:e8/00, 296:0e/00, 298:66/00, 299:81/00, 300:3e/00, 301:1c/00
, 302:80/00, 303:74/00, 304:86/00, 305:49/00, 306:59/00, 307:75/00
, 308:74/00, 309:e9/00, 310:f8/00, 311:02/00, 312:66/00, 313:03/00
, 314:06/00, 315:60/00, 316:7b/00, 317:66/00, 318:13/00, 319:16/00
, 320:64/00, 321:7b/00, 322:b9/00, 323:10/00, 325:eb/00, 326:2b/00
, 327:66/00, 328:52/00, 329:66/00, 330:50/00, 331:06/00, 332:53/00
, 333:6a/00, 334:01/00, 335:6a/00, 336:10/00, 337:89/00, 338:e6/00
, 339:66/00, 340:60/00, 341:b4/00, 342:42/00, 343:e8/00, 344:77/00
, 346:66/00, 347:61/00, 348:8d/00, 349:64/00, 350:10/00, 351:72/00
, 352:01/00, 353:c3/00, 354:66/00, 355:60/00, 356:31/00, 357:c0/00
, 358:e8/00, 359:68/00, 361:66/00, 362:61/00, 363:e2/00, 364:da/00
, 365:c6/00, 366:06/00, 367:46/00, 368:7d/00, 369:2b/00, 370:66/00
, 371:60/00, 372:66/00, 373:0f/00, 374:b7/00, 375:36/00, 376:18/00
, 377:7c/00, 378:66/00, 379:0f/00, 380:b7/00, 381:3e/00, 382:1a/00
, 383:7c/00, 384:66/00, 385:f7/00, 386:f6/00, 387:31/00, 388:c9/00
, 389:87/00, 390:d1/00, 391:66/00, 392:f7/00, 393:f7/00, 394:66/00
, 395:3d/00, 396:ff/00, 397:03/00, 400:77/00, 401:17/00, 402:c0/00
, 403:e4/00, 404:06/00, 405:41/00, 406:08/00, 407:e1/00, 408:88/00
, 409:c5/00, 410:88/00, 411:d6/00, 412:b8/00, 413:01/00, 414:02/00
, 415:e8/00, 416:2f/00, 418:66/00, 419:61/00, 420:72/00, 421:01/00
, 422:c3/00, 423:e2/00, 424:c9/00, 425:31/00, 426:f6/00, 427:8e/00
, 428:d6/00, 429:bc/00, 430:68/00, 431:7b/00, 432:8e/00, 433:de/00
, 434:66/00, 435:8f/00, 436:06/00, 437:78/00, 439:be/00, 440:da/00
, 441:7d/00, 442:ac/00, 443:20/00, 444:c0/00, 445:74/00, 446:09/00
, 447:b4/00, 448:0e/00, 449:bb/00, 450:07/00, 452:cd/00, 453:10/00
, 454:eb/00, 455:f2/00, 456:31/00, 457:c0/00, 458:cd/00, 459:16/00
, 460:cd/00, 461:19/00, 462:f4/00, 463:eb/00, 464:fd/00, 465:8a/00
, 466:16/00, 467:74/00, 468:7b/00, 469:06/00, 470:cd/00, 471:13/00
, 472:07/00, 473:c3/00, 474:42/00, 475:6f/00, 476:6f/00, 477:74/00
, 478:20/00, 479:65/00, 480:72/00, 481:72/00, 482:6f/00, 483:72/00
, 484:0d/00, 485:0a/00, 504:fe/00, 505:02/00, 506:b2/00, 507:3e/00
, 508:18/00, 509:37/00
1) Copy original to backup
2) Copy backup to original
3) No action
[123?q]?
Regards,
Berto
-- System Information:
Debian Release: 13.2
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)
Kernel: Linux 6.12.57+deb13-amd64 (SMP w/4 CPU threads; PREEMPT)
Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_IE.UTF-8, LC_CTYPE=en_IE.UTF-8 (charmap=UTF-8), LANGUAGE=en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages syslinux depends on:
ii libc6 2.41-12
ii mtools 4.0.48-1
Versions of packages syslinux recommends:
ii syslinux-common 3:6.04~git20190206.bf6db5b4+dfsg1-3.1
Versions of packages syslinux suggests:
ii dosfstools 4.2-1.2
-- no debconf information
Reply to: