syzbot


possible deadlock in mnt_want_write (2)

Status: upstream: reported C repro on 2021/06/15 16:59
Labels: integrity overlayfs (incorrect?)
Reported-by: syzbot+b42fe626038981fb7bfa@syzkaller.appspotmail.com
First crash: 728d, last: 3h43m

Cause bisection: introduced by (bisect log) [no-op commit]:
commit b9fc8b4a591811546fec2dbef7e9f809362100c9
Author: Grant Seltzer <grantseltzer@gmail.com>
Date: Mon Feb 22 19:58:46 2021 +0000

  bpf: Add kernel/modules BTF presence checks to bpftool feature command

Crash: WARNING in kvm_wait (log)
Repro: C syz .config
Duplicate bugs (2)
duplicates (2):
Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
possible deadlock in ovl_maybe_copy_up overlayfs C unreliable 807 2d16h 928d 0/24 closed as dup on 2023/06/06 09:30
possible deadlock in process_measurement (3) overlayfs C error 186 4d11h 760d 0/24 closed as dup on 2023/06/06 09:59
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] Monthly overlayfs report (May 2023) 0 (1) 2023/05/06 08:19
[syzbot] Monthly overlayfs report 0 (1) 2023/04/05 08:55
[syzbot] possible deadlock in mnt_want_write (2) 5 (7) 2022/07/06 22:24
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in mnt_want_write origin:upstream C 4 10d 80d 0/3 upstream: reported C repro on 2023/03/21 10:01
upstream possible deadlock in mnt_want_write fs C done done 662 974d 1781d 17/24 fixed on 2020/11/16 12:12
linux-6.1 possible deadlock in mnt_want_write origin:upstream C 3 25d 73d 0/3 upstream: reported C repro on 2023/03/28 13:05
linux-4.19 possible deadlock in mnt_want_write romfs C 730 94d 1512d 0/1 upstream: reported C repro on 2019/04/19 16:54
android-49 possible deadlock in mnt_want_write 1 1764d 1764d 0/3 auto-closed as invalid on 2019/02/22 14:57
linux-4.14 possible deadlock in mnt_want_write ubifs C 10467 94d 1506d 0/1 upstream: reported C repro on 2019/04/25 05:09
Last patch testing requests (2)
Created Duration User Patch Repo Result
2022/07/03 07:07 19m hdanton@sina.com patch http://kernel.source.codeaurora.cn/pub/scm/linux/kernel/git/torvalds/linux.git 089866061428 OK log
2022/07/03 01:34 17m hdanton@sina.com patch http://kernel.source.codeaurora.cn/pub/scm/linux/kernel/git/torvalds/linux.git 089866061428 error

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.3.0-rc3-syzkaller-00012-g17214b70a159 #0 Not tainted
------------------------------------------------------
syz-executor392/5082 is trying to acquire lock:
ffff88814b9b0460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:394

but task is already holding lock:
ffff88801fe5ace0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x7c0/0x1ce0 security/integrity/ima/ima_main.c:262

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&iint->mutex){+.+.}-{3:3}:
       lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       process_measurement+0x7c0/0x1ce0 security/integrity/ima/ima_main.c:262
       ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:539
       do_open fs/namei.c:3562 [inline]
       path_openat+0x280a/0x3170 fs/namei.c:3715
       do_filp_open+0x234/0x490 fs/namei.c:3742
       do_sys_openat2+0x13f/0x500 fs/open.c:1348
       do_sys_open fs/open.c:1364 [inline]
       __do_sys_openat fs/open.c:1380 [inline]
       __se_sys_openat fs/open.c:1375 [inline]
       __x64_sys_openat+0x247/0x290 fs/open.c:1375
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (sb_writers#4){.+.+}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3098 [inline]
       check_prevs_add kernel/locking/lockdep.c:3217 [inline]
       validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
       lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1477 [inline]
       sb_start_write+0x4d/0x1c0 include/linux/fs.h:1552
       mnt_want_write+0x3f/0x90 fs/namespace.c:394
       ovl_maybe_copy_up+0x115/0x180 fs/overlayfs/copy_up.c:1125
       ovl_open+0x10c/0x2b0 fs/overlayfs/file.c:153
       do_dentry_open+0x7f9/0x10f0 fs/open.c:920
       vfs_open fs/open.c:1051 [inline]
       dentry_open+0xc5/0x120 fs/open.c:1067
       ima_calc_file_hash+0x15d/0x1c00 security/integrity/ima/ima_crypto.c:558
       ima_collect_measurement+0x3a7/0x880 security/integrity/ima/ima_api.c:293
       process_measurement+0xfdb/0x1ce0 security/integrity/ima/ima_main.c:341
       ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:539
       do_open fs/namei.c:3562 [inline]
       path_openat+0x280a/0x3170 fs/namei.c:3715
       do_filp_open+0x234/0x490 fs/namei.c:3742
       do_sys_openat2+0x13f/0x500 fs/open.c:1348
       do_sys_open fs/open.c:1364 [inline]
       __do_sys_openat fs/open.c:1380 [inline]
       __se_sys_openat fs/open.c:1375 [inline]
       __x64_sys_openat+0x247/0x290 fs/open.c:1375
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&iint->mutex);
                               lock(sb_writers#4);
                               lock(&iint->mutex);
  lock(sb_writers#4);

 *** DEADLOCK ***

1 lock held by syz-executor392/5082:
 #0: ffff88801fe5ace0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x7c0/0x1ce0 security/integrity/ima/ima_main.c:262

stack backtrace:
CPU: 1 PID: 5082 Comm: syz-executor392 Not tainted 6.3.0-rc3-syzkaller-00012-g17214b70a159 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3098 [inline]
 check_prevs_add kernel/locking/lockdep.c:3217 [inline]
 validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1477 [inline]
 sb_start_write+0x4d/0x1c0 include/linux/fs.h:1552
 mnt_want_write+0x3f/0x90 fs/namespace.c:394
 ovl_maybe_copy_up+0x115/0x180 fs/overlayfs/copy_up.c:1125
 ovl_open+0x10c/0x2b0 fs/overlayfs/file.c:153
 do_dentry_open+0x7f9/0x10f0 fs/open.c:920
 vfs_open fs/open.c:1051 [inline]
 dentry_open+0xc5/0x120 fs/open.c:1067
 ima_calc_file_hash+0x15d/0x1c00 security/integrity/ima/ima_crypto.c:558
 ima_collect_measurement+0x3a7/0x880 security/integrity/ima/ima_api.c:293
 process_measurement+0xfdb/0x1ce0 security/integrity/ima/ima_main.c:341
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:539
 do_open fs/namei.c:3562 [inline]
 path_openat+0x280a/0x3170 fs/namei.c:3715
 do_filp_open+0x234/0x490 fs/namei.c:3742
 do_sys_openat2+0x13f/0x500 fs/open.c:1348
 do_sys_open fs/open.c:1364 [inline]
 __do_sys_openat fs/open.c:1380 [inline]
 __se_sys_openat fs/open.c:1375 [inline]
 __x64_sys_openat+0x247/0x290 fs/open.c:1375
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fc31b6b8d29
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcecef4908 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 003065

Crashes (608):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Manager Title
2023/03/21 14:52 upstream 17214b70a159 7939252e .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2022/11/03 23:00 upstream f2f32f8af2b0 6d752409 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2022/07/02 17:27 upstream 089866061428 1434eec0 .config console log report syz C ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/06/09 13:18 upstream 33f2b5785a2b 058b3a5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/09 00:04 upstream 25041a4c02c7 058b3a5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/08 14:18 upstream 5f63595ebd82 058b3a5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/08 04:39 upstream a27648c74210 058b3a5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/07 23:45 upstream a27648c74210 058b3a5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/07 11:39 upstream a4d7d7011219 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/06 21:52 upstream a4d7d7011219 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/02 23:00 upstream c43a6ff9f93f a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/02 14:39 upstream c43a6ff9f93f a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/06/01 14:58 upstream 929ed21dfdb6 babc4389 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/31 15:22 upstream afead42fdfca 09898419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/31 05:45 upstream afead42fdfca 09898419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/27 05:05 upstream 0d85b27b0cc6 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/26 12:57 upstream 9db898594c54 b40ef614 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/26 11:02 upstream 9db898594c54 b40ef614 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/25 01:46 upstream 9d646009f65d 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/24 17:24 upstream 9d646009f65d 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/23 18:04 upstream ae8373a5add4 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/23 08:19 upstream 421ca22e3138 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/22 17:07 upstream 44c026a73be8 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/22 12:46 upstream 44c026a73be8 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/22 08:24 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/22 04:54 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/22 00:42 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/21 15:08 upstream 0dd2a6fb1e34 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/19 22:07 upstream cbd6ac3837cd 96689200 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/19 12:44 upstream 2d1bcbc6cd70 3bb7af1d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/18 17:40 upstream 4d6d4c7f541d 3bb7af1d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/18 06:10 upstream 1b66c114d161 3bb7af1d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/18 00:53 upstream 1b66c114d161 3bb7af1d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/16 08:04 upstream f1fcbaa18b28 71b00cfb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/15 16:40 upstream f1fcbaa18b28 c4d362e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/15 05:58 upstream f1fcbaa18b28 2b9ba477 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/14 20:41 upstream bb7c241fae62 2b9ba477 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/13 09:54 upstream 9a48d6046722 2b9ba477 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/12 21:24 upstream cc3c44c9fda2 ecca8a24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/11 11:35 upstream d295b66a7b66 0fbd49f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/11 10:02 upstream 80e62bc8487b 0fbd49f4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/11 06:57 upstream 80e62bc8487b 0fbd49f4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/10 20:35 upstream ad2fd53a7870 0fbd49f4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/10 04:41 upstream 16a8829130ca 1964022b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/09 22:37 upstream 1dc3731daf1f 30aa2a7e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/09 20:55 upstream 1dc3731daf1f 30aa2a7e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/09 15:35 upstream ba0ad6ed89fd 30aa2a7e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in mnt_want_write
2023/05/09 10:15 upstream ba0ad6ed89fd f4168103 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/09 01:42 upstream ba0ad6ed89fd f4168103 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/08 22:17 upstream ba0ad6ed89fd 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2023/05/08 02:44 upstream ac9a78681b92 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
2021/06/11 16:55 upstream 06af8679449d 1ba81399 .config console log report info ci-upstream-kasan-gce-smack-root possible deadlock in mnt_want_write
* Struck through repros no longer work on HEAD.