kernel panic: EXT4-fs (device loop0): panic forced after error

Status: upstream: reported C repro on 2024/03/06 01:35
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+9a5d91066721eed10205@syzkaller.appspotmail.com
First crash: 889d, last: 9d04h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/03/06 upstream (ToT) 5847c9777c30 C [report] kernel panic: EXT4-fs (device loop0): panic forced after error
▶ ▼ Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel panic: EXT4-fs (device loop0): panic forced after error (2) ext4 2 syz, C error 2 1325d 1322d 0/29 closed as invalid on 2023/01/03 13:41
linux-6.1 kernel panic: EXT4-fs (device loop0): panic forced after error origin:upstream 2 syz, C error 1 561d 995d 0/3 upstream: reported C repro on 2023/11/20 19:54
upstream kernel panic: EXT4-fs (device loop0): panic forced after error ext4 2 syz, C 1 3020d 3020d 0/29 closed as invalid on 2018/06/12 14:01
upstream kernel panic: EXT4-fs (device loop0): panic forced after error (3) ext4 2 syz, C inconclusive 1 1095d 1091d 0/29 closed as invalid on 2023/08/17 14:21
android-6-1 kernel panic: EXT4-fs (device loop0): panic forced after error origin:upstream 2 syz, C error inconclusive 1 138d 1089d 0/2 upstream: reported C repro on 2023/08/18 16:47
android-5-10 kernel panic: EXT4-fs (device loop0): panic forced after error ext4 2 syz, C 1 1326d 1326d 0/2 closed as invalid on 2022/12/26 14:10
android-54 kernel panic: EXT4-fs (device loop0): panic forced after error 2 syz, C 1 515d 1094d 0/2 upstream: reported C repro on 2023/08/13 09:27
android-5-15 kernel panic: EXT4-fs (device loop0): panic forced after error ext4 2 syz, C error 1 1326d 1326d 0/2 closed as invalid on 2022/12/26 14:01
android-5-10 kernel panic: EXT4-fs (device loop0): panic forced after error (2) 2 syz, C inconclusive 1 121d 1095d 0/2 upstream: reported C repro on 2023/08/12 21:25
android-49 kernel panic: EXT4-fs (device loop0): panic forced after error 2 syz, C 2 3020d 3020d 0/3 closed as invalid on 2018/05/07 15:46
▶ ▼ Last patch testing requests (8)
Created Duration User Patch Repo Result
2026/08/02 21:41 22m retest repro linux-5.15.y report log
2026/05/21 16:36 27m retest repro linux-5.15.y error
2026/02/17 06:31 10m retest repro linux-5.15.y report log
2025/12/09 00:48 51m retest repro linux-5.15.y report log
2025/09/28 16:49 10m retest repro linux-5.15.y report log
2025/07/20 14:58 13m retest repro linux-5.15.y report log
2025/05/11 13:56 10m retest repro linux-5.15.y report log
2025/02/24 03:12 11m retest repro linux-5.15.y report log

Sample crash report:
EXT4-fs warning (device loop0): ext4_update_dynamic_rev:1053: updating to rev 1 because of new feature flag, running e2fsck is recommended
EXT4-fs error (device loop0): ext4_validate_block_bitmap:429: comm syz-executor631: bg 0: block 46: invalid block bitmap
Kernel panic - not syncing: EXT4-fs (device loop0): panic forced after error
CPU: 1 PID: 3960 Comm: syz-executor631 Not tainted 5.15.150-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 panic+0x304/0x8b4 kernel/panic.c:309
 __ext4_error_inode+0x0/0x338 fs/ext4/super.c:667
 __ext4_error+0x178/0x248 fs/ext4/super.c:756
 ext4_validate_block_bitmap+0xd98/0x1114
 ext4_wait_block_bitmap+0x194/0x1e0 fs/ext4/balloc.c:579
 ext4_read_block_bitmap+0x54/0xe8 fs/ext4/balloc.c:591
 ext4_mb_clear_bb fs/ext4/mballoc.c:6034 [inline]
 ext4_free_blocks+0xd48/0x2bf0 fs/ext4/mballoc.c:6279
 ext4_remove_blocks fs/ext4/extents.c:2519 [inline]
 ext4_ext_rm_leaf fs/ext4/extents.c:2685 [inline]
 ext4_ext_remove_space+0x1c48/0x4254 fs/ext4/extents.c:2933
 ext4_ext_truncate+0x188/0x250 fs/ext4/extents.c:4448
 ext4_truncate+0x9c4/0x1058 fs/ext4/inode.c:4238
 ext4_process_orphan+0x180/0x2b8 fs/ext4/orphan.c:339
 ext4_orphan_cleanup+0x8bc/0x1048 fs/ext4/orphan.c:474
 ext4_fill_super+0x8044/0x8768 fs/ext4/super.c:4966
 mount_bdev+0x274/0x370 fs/super.c:1387
 ext4_mount+0x44/0x58 fs/ext4/super.c:6582
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
 vfs_get_tree+0x90/0x274 fs/super.c:1517
 do_new_mount+0x278/0x8fc fs/namespace.c:3005
 path_mount+0x594/0x101c fs/namespace.c:3335
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount fs/namespace.c:3533 [inline]
 __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3533
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
SMP: stopping secondary CPUs
Kernel Offset: disabled
CPU features: 0x0,000081c1,21302e40
Memory Limit: none
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/06 01:34 linux-5.15.y 80efc6265290 f39a7eed .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 kernel panic: EXT4-fs (device loop0): panic forced after error
* Struck through repros no longer work on HEAD.