syzbot


BUG: Dentry still in use [unmount of overlay overlay]

Status: upstream: reported C repro on 2020/12/25 03:22
Reported-by: syzbot+9eac2eb238331e7acdfe@syzkaller.appspotmail.com
First crash: 709d, last: 410d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 BUG: Dentry still in use [unmount of ext4 loop0] C error 63 368d 406d 0/2 closed as dup on 2021/10/28 13:08
android-5-10 BUG: Dentry still in use [unmount of overlay overlay] C error 2 401d 401d 0/2 closed as dup on 2021/10/29 08:14
android-5-10 BUG: Dentry still in use in unmount C done 1184 284d 296d 2/2 fixed on 2022/02/25 03:20
android-54 BUG: Dentry still in use [unmount of ramfs ramfs] C 476 303d 625d 0/2 upstream: reported C repro on 2021/03/19 07:18

Sample crash report:
incfs: Can't find or create .index dir in ./file1
BUG: Dentry 000000007f667ea2{i=0,n=.index}  still in use (1) [unmount of overlay overlay]
------------[ cut here ]------------
WARNING: CPU: 0 PID: 350 at fs/dcache.c:1597 umount_check+0x179/0x1c0 fs/dcache.c:1588
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 350 Comm: syz-executor917 Not tainted 5.4.85-syzkaller-00188-g8657d5d6282f #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 63 3e 1d 85 4c 89 fe 4c 89 f2 4c 89 f9 45 89 e8 31 c0 55 e8 27 54 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:ffff8881e8fafa50 EFLAGS: 00010296
RAX: 0000000000000059 RBX: ffffffff8548e758 RCX: f109591a4fe10b00
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffff8881e8824420 R08: ffffffff814e3421 R09: ffffed103ee05e08
R10: ffffed103ee05e08 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffff8881eff8b770
 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_anon_super+0x36/0x60 fs/super.c:1108
 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
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xcc2/0x2830 kernel/exit.c:811
 do_group_exit+0x155/0x2b0 kernel/exit.c:909
 __do_sys_exit_group+0x13/0x20 kernel/exit.c:920
 __se_sys_exit_group+0x10/0x10 kernel/exit.c:918
 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:918
 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x43f808
Code: Bad RIP value.
RSP: 002b:00007ffd50db58d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000043f808
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
RBP: 00000000004bf7b0 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (20):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-android-5-4-kasan 2020/12/25 03:44 android12-5.4 8657d5d6282f c2c1d1dd .config log report syz C
ci2-android-5-4-kasan 2021/10/20 01:49 android12-5.4 5970ec26e0c8 466b7db1 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/09/30 03:45 android12-5.4 12806d81361b be530f6c .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/09/27 07:29 android12-5.4 d52ac987ad2a 78494d16 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/08/23 12:56 android12-5.4 3ce13296e72d b599f2fc .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/08/23 07:53 android12-5.4 3ce13296e72d b599f2fc .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/08/12 00:04 android12-5.4 95a38d5c8d5b 6972b106 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/06/01 23:22 android12-5.4 114add618c71 032639db .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/05/27 01:04 android12-5.4 54f14b62ffed 858ea628 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/05/18 03:44 android12-5.4 74d682ab7415 a343ba6b .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/05/02 03:12 android12-5.4 a50424773496 77e2b668 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/05/01 04:20 android12-5.4 a50424773496 77e2b668 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/04/17 18:26 android12-5.4 9d49fb308497 7e2b734b .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/04/16 14:13 android12-5.4 4d45d5467a1b 7e2b734b .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/04/02 19:39 android12-5.4 708026dc169c 6a81331a .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/03/09 10:43 android12-5.4 16e1b2475015 09fbf400 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/02/13 14:17 android12-5.4 dbfedfa31471 98682e5e .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/02/11 19:25 android12-5.4 82c67a98c749 a5f86b15 .config log report info BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-4-kasan 2021/01/04 07:05 android12-5.4 e627b02af655 79264ae3 .config log report info
ci2-android-5-4-kasan 2020/12/25 03:21 android12-5.4 8657d5d6282f c2c1d1dd .config log report info
* Struck through repros no longer work on HEAD.