syzbot


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

Status: closed as dup on 2021/10/29 08:14
Reported-by: syzbot+8d7e3fbb6de24402a40f@syzkaller.appspotmail.com
First crash: 463d, last: 463d

Cause bisection: failed (bisect log)
Duplicate of (1):
Title Repro Cause bisect Fix bisect Count Last Reported
BUG: Dentry still in use [unmount of ramfs ramfs] C error 3 469d 470d
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 430d 468d 0/2 closed as dup on 2021/10/28 13:08
android-5-10 BUG: Dentry still in use in unmount C done 1184 346d 358d 2/2 fixed on 2022/02/25 03:20
android-54 BUG: Dentry still in use [unmount of ramfs ramfs] C 476 365d 687d 0/2 upstream: reported C repro on 2021/03/19 07:18
android-54 BUG: Dentry still in use [unmount of overlay overlay] C 20 472d 771d 0/2 upstream: reported C repro on 2020/12/25 03:22

Sample crash report:
BUG: Dentry ffff888119dd8bb0{i=0,n=.index}  still in use (1) [unmount of overlay overlay]
------------[ cut here ]------------
WARNING: CPU: 1 PID: 366 at fs/dcache.c:1616 umount_check+0x18d/0x1d0 syzkaller/managers/android-5-10/kernel/fs/dcache.c:1607
Modules linked in:
CPU: 1 PID: 366 Comm: syz-executor373 Not tainted 5.10.76-syzkaller-01178-g4944ec82ebb9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:umount_check+0x18d/0x1d0 syzkaller/managers/android-5-10/kernel/fs/dcache.c:1607
Code: 8b 0b 49 81 c6 f8 03 00 00 48 c7 c7 00 40 2e 85 4c 89 e6 48 8b 55 d0 4c 89 e1 45 89 f8 31 c0 41 56 e8 5e d9 9e ff 48 83 c4 08 <0f> 0b e9 f1 fe ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c c9 fe ff
RSP: 0018:ffffc9000022fad0 EFLAGS: 00010292
RAX: 0000000000000059 RBX: ffffffff866d06a0 RCX: 99af438855119a00
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffc9000022fb00 R08: ffffffff81545288 R09: 0000000000000003
R10: fffff52000045ead R11: 0000000000000004 R12: ffff888119dd8bb0
R13: dffffc0000000000 R14: ffff88811d8bb3f8 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2150f191d0 CR3: 000000010c74f000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 d_walk+0x309/0x540 syzkaller/managers/android-5-10/kernel/fs/dcache.c:1326
 do_one_tree syzkaller/managers/android-5-10/kernel/fs/dcache.c:1623 [inline]
 shrink_dcache_for_umount+0x8e/0x1b0 syzkaller/managers/android-5-10/kernel/fs/dcache.c:1639
 generic_shutdown_super+0x66/0x2c0 syzkaller/managers/android-5-10/kernel/fs/super.c:447
 kill_anon_super+0x3c/0x70 syzkaller/managers/android-5-10/kernel/fs/super.c:1108
 deactivate_locked_super+0xb0/0x100 syzkaller/managers/android-5-10/kernel/fs/super.c:335
 deactivate_super+0xa5/0xd0 syzkaller/managers/android-5-10/kernel/fs/super.c:366
 cleanup_mnt+0x45f/0x510 syzkaller/managers/android-5-10/kernel/fs/namespace.c:1118
 __cleanup_mnt+0x19/0x20 syzkaller/managers/android-5-10/kernel/fs/namespace.c:1125
 task_work_run+0x147/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:154
 exit_task_work syzkaller/managers/android-5-10/kernel/./include/linux/task_work.h:30 [inline]
 do_exit+0x70e/0x23a0 syzkaller/managers/android-5-10/kernel/kernel/exit.c:813
 do_group_exit+0x16a/0x2d0 syzkaller/managers/android-5-10/kernel/kernel/exit.c:910
 __do_sys_exit_group+0x17/0x20 syzkaller/managers/android-5-10/kernel/kernel/exit.c:921
 __se_sys_exit_group+0x14/0x20 syzkaller/managers/android-5-10/kernel/kernel/exit.c:919
 __x64_sys_exit_group+0x3b/0x40 syzkaller/managers/android-5-10/kernel/kernel/exit.c:919
 do_syscall_64+0x31/0x70 syzkaller/managers/android-5-10/kernel/arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f2150ea4579
Code: Unable to access opcode bytes at RIP 0x7f2150ea454f.
RSP: 002b:00007fff54a02298 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f2150f18330 RCX: 00007f2150ea4579
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 00007f2150f12e40
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2150f18330
R13: 00

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-android-5-10 2021/10/28 22:11 android12-5.10-lts 4944ec82ebb9 be531bb4 .config console log report syz C BUG: Dentry still in use [unmount of overlay overlay]
ci2-android-5-10 2021/10/28 21:36 android12-5.10-lts 4944ec82ebb9 be531bb4 .config console log report info BUG: Dentry still in use [unmount of overlay overlay]
* Struck through repros no longer work on HEAD.