syzbot


BUG: Dentry still in use [unmount of erofs loop5]

Status: auto-closed as invalid on 2021/05/25 23:05
Reported-by: syzbot+a2a70c72588eabdcb56a@syzkaller.appspotmail.com
First crash: 1269d, last: 1269d

Sample crash report:
BUG: Dentry 00000000622f864d{i=0,n=.index}  still in use (2) [unmount of erofs loop5]
------------[ cut here ]------------
WARNING: CPU: 1 PID: 388 at fs/dcache.c:1597 umount_check+0x179/0x1c0 fs/dcache.c:1588
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 388 Comm: syz-executor.5 Not tainted 5.4.92-syzkaller-00473-g18b1db92afb1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1dd/0x24e lib/dump_stack.c:118
 panic+0x285/0x750 kernel/panic.c:221
 __warn+0x1fd/0x200 kernel/panic.c:582
 report_bug+0x390/0x4d0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 do_error_trap arch/x86/kernel/traps.c:272 [inline]
 do_invalid_op+0x6e/0x110 arch/x86/kernel/traps.c:291
 invalid_op+0x1e/0x30 arch/x86/entry/entry_64.S:1029
RIP: 0010:umount_check+0x179/0x1c0 fs/dcache.c:1588
Code: ff 4c 8b 0b 48 81 c5 20 04 00 00 48 c7 c7 23 58 1d 85 4c 89 fe 4c 89 f2 4c 89 f9 45 89 e8 31 c0 55 e8 a7 36 b0 ff 48 83 c4 08 <0f> 0b e9 fd fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c d4 fe ff
RSP: 0018:ffff8881b02d7c38 EFLAGS: 00010282
RAX: 0000000000000055 RBX: ffffffff8549b420 RCX: 43b14af49d1daa00
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffff8881ab2ba420 R08: ffffffff814e45f1 R09: ffffed103ee25e08
R10: ffffed103ee25e08 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000002 R14: 0000000000000000 R15: ffff8881e870fbb0
 d_walk+0x2e9/0x570 fs/dcache.c:1307
 do_one_tree fs/dcache.c:1604 [inline]
 shrink_dcache_for_umount+0x8a/0x1b0 fs/dcache.c:1620
 generic_shutdown_super+0x63/0x2a0 fs/super.c:447
 kill_block_super+0x79/0xd0 fs/super.c:1444
 erofs_kill_sb+0x5b/0xc0 fs/erofs/super.c:442
 deactivate_locked_super+0xaf/0x100 fs/super.c:335
 deactivate_super+0x1b8/0x280 fs/super.c:366
 cleanup_mnt+0x432/0x4e0 fs/namespace.c:1102
 task_work_run+0x176/0x1a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:163 [inline]
 prepare_exit_to_usermode+0x2b0/0x310 arch/x86/entry/common.c:194
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x460c47
Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe194a2928 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000460c47
RDX: 00000000004033a8 RSI: 0000000000000002 RDI: 00007ffe194a29d0
RBP: 000000000002e531 R08: 0000000000000000 R09: 000000000000000b
R10: 0000000000000005 R11: 0000000000000246 R12: 00007ffe194a3a80
R13: 000000000359a940 R14: 0000000000000000 R15: 000000000002e4d6
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
2021/01/25 23:04 android12-5.4 18b1db92afb1 52e37319 .config console log report info ci2-android-5-4-kasan BUG: Dentry still in use [unmount of erofs loop5]
* Struck through repros no longer work on HEAD.