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

Status: upstream: reported C repro on 2023/08/18 16:47
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+73216f240bb65f795dd5@syzkaller.appspotmail.com
First crash: 1078d, last: 128d
Cause bisection: failed (error log, bisect log)
  
Fix bisection: the issue occurs on the latest tested release (bisect log)
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2023/08/18 lts (merge base) b1644a0031cf C [report] kernel panic: EXT4-fs (device loop0): panic forced after error
2023/08/18 upstream (ToT) 0e8860d2125f 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 1315d 1311d 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 551d 984d 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 3009d 3009d 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 1084d 1080d 0/29 closed as invalid on 2023/08/17 14:21
linux-5.15 kernel panic: EXT4-fs (device loop0): panic forced after error origin:upstream 2 syz, C error 1 165d 878d 0/3 upstream: reported C repro on 2024/03/06 01:35
android-5-10 kernel panic: EXT4-fs (device loop0): panic forced after error ext4 2 syz, C 1 1315d 1315d 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 504d 1084d 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 1315d 1315d 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 111d 1084d 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 3009d 3009d 0/3 closed as invalid on 2018/05/07 15:46
▶ ▼ Last patch testing requests (3)
Created Duration User Patch Repo Result
2026/06/06 22:32 49m retest repro android14-6.1 log
2026/03/26 06:42 6m retest repro android14-6.1 report log
2026/01/14 20:08 6m retest repro android14-6.1 report log
▶ ▼ Fix bisection attempts (11)
Created Duration User Patch Repo Result
2024/09/08 11:13 1h48m bisect fix android14-6.1 OK (0) job log
2024/08/06 18:31 3h28m bisect fix android14-6.1 OK (0) job log log
2024/06/27 22:53 2h00m bisect fix android14-6.1 OK (0) job log log
2024/05/21 03:54 1h49m bisect fix android14-6.1 OK (0) job log log
2024/04/16 00:52 2h12m bisect fix android14-6.1 OK (0) job log log
2024/03/13 08:12 1h49m bisect fix android14-6.1 OK (0) job log log
2024/02/08 01:38 1h45m bisect fix android14-6.1 OK (0) job log log
2024/01/01 17:02 1h38m bisect fix android14-6.1 OK (0) job log log
2023/12/02 10:06 2h00m bisect fix android14-6.1 OK (0) job log log
2023/11/01 07:57 1h38m bisect fix android14-6.1 OK (0) job log log
2023/10/01 22:48 1h37m bisect fix android14-6.1 OK (0) job log log

Sample crash report:
loop0: detected capacity change from 0 to 512
ext2: Unknown parameter ''
EXT4-fs (loop0): feature flags set on rev 0 fs, running e2fsck is recommended
EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended
EXT4-fs warning (device loop0): ext4_update_dynamic_rev:1084: updating to rev 1 because of new feature flag, running e2fsck is recommended
EXT4-fs error (device loop0): ext4_validate_block_bitmap:399: comm syz-executor238: bg 0: block 46: invalid block bitmap
Kernel panic - not syncing: EXT4-fs (device loop0): panic forced after error
CPU: 0 PID: 317 Comm: syz-executor238 Not tainted 6.1.25-syzkaller-00052-gc2611a04b92f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
 dump_stack+0x15/0x17 lib/dump_stack.c:113
 panic+0x283/0x660 kernel/panic.c:339
 ext4_handle_error+0x83e/0x890 fs/ext4/super.c:687
 __ext4_error+0x260/0x480 fs/ext4/super.c:778
 ext4_validate_block_bitmap+0xd2f/0x1070 fs/ext4/balloc.c:398
 ext4_wait_block_bitmap+0x144/0x1d0 fs/ext4/balloc.c:541
 ext4_read_block_bitmap+0x41/0x80 fs/ext4/balloc.c:553
 ext4_mb_clear_bb fs/ext4/mballoc.c:5935 [inline]
 ext4_free_blocks+0x1009/0x2c10 fs/ext4/mballoc.c:6179
 ext4_remove_blocks fs/ext4/extents.c:2545 [inline]
 ext4_ext_rm_leaf fs/ext4/extents.c:2711 [inline]
 ext4_ext_remove_space+0x248b/0x4f50 fs/ext4/extents.c:2959
 ext4_ext_truncate+0x1f4/0x320 fs/ext4/extents.c:4417
 ext4_truncate+0x96c/0xfb0 fs/ext4/inode.c:4274
 ext4_process_orphan+0x1d3/0x2f0 fs/ext4/orphan.c:339
 ext4_orphan_cleanup+0xa4a/0x11e0 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5516 [inline]
 ext4_fill_super+0x7d37/0x8450 fs/ext4/super.c:5644
 get_tree_bdev+0x440/0x680 fs/super.c:1348
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5674
 vfs_get_tree+0x88/0x290 fs/super.c:1555
 do_new_mount+0x28b/0xac0 fs/namespace.c:3040
 path_mount+0x671/0x1070 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2c4/0x3b0 fs/namespace.c:3568
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4d87926a99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd7a8b7098 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f4d87926a99
RDX: 00000000200001c0 RSI: 00000000200006c0 RDI: 0000000020000640
RBP: 000000000000602d R08: 0000000000000000 R09: 0000555556b7c4c0
R10: 000000003f000000 R11: 0000000000000246 R12: 00007ffd7a8b70c0
R13: 00007ffd7a8b70ac R14: 431bde82d7b634db R15: 00007f4d8796f03b
 </TASK>
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/18 16:44 android14-6.1 c2611a04b92f acb1ba71 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel panic: EXT4-fs (device loop0): panic forced after error
* Struck through repros no longer work on HEAD.