syzbot


possible deadlock in mnt_want_write

Status: upstream: reported C repro on 2023/03/21 10:01
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+3750793de72b871c45e4@syzkaller.appspotmail.com
First crash: 392d, last: 140d
Fix commit to backport (bisect log) :
tree: upstream
commit a0e6a017ab56936c0405fe914a793b241ed25ee0
Author: MaΓ­ra Canal <mcanal@igalia.com>
Date: Tue May 23 12:32:08 2023 +0000

  drm/vkms: Fix race-condition between the hrtimer and the atomic commit

  
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: possible deadlock in ovl_maybe_copy_up (log)
Repro: C syz .config
  
Bug presence (3)
Date Name Commit Repro Result
2023/11/10 linux-5.15.y (ToT) 80529b4968a8 C [report] possible deadlock in mnt_want_write
2023/05/11 upstream (ToT) 105131df9c3b C [report] possible deadlock in mnt_want_write
2023/11/10 upstream (ToT) 89cdf9d55601 C Didn't crash
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in mnt_want_write fs C done done 662 1286d 2093d 15/26 fixed on 2020/11/16 12:12
linux-6.1 possible deadlock in mnt_want_write origin:upstream missing-backport C done 56 141d 385d 0/3 upstream: reported C repro on 2023/03/28 13:05
linux-4.19 possible deadlock in mnt_want_write romfs C 730 406d 1823d 0/1 upstream: reported C repro on 2019/04/19 16:54
android-49 possible deadlock in mnt_want_write 1 2076d 2076d 0/3 auto-closed as invalid on 2019/02/22 14:57
upstream possible deadlock in mnt_want_write (2) integrity overlayfs C done 867 167d 1035d 25/26 fixed on 2023/12/21 01:43
upstream possible deadlock in mnt_want_write (3) kernfs 9 3d03h 106d 0/26 upstream: reported on 2024/01/01 07:31
linux-4.14 possible deadlock in mnt_want_write ubifs C 10467 406d 1818d 0/1 upstream: reported C repro on 2019/04/25 05:09
Fix bisection attempts (4)
Created Duration User Patch Repo Result
2023/12/10 06:56 4h47m fix candidate upstream job log (1)
2023/10/20 23:31 1h06m bisect fix linux-5.15.y job log (0) log
2023/05/25 15:16 34m bisect fix linux-5.15.y job log (0) log
2023/04/21 13:00 40m bisect fix linux-5.15.y job log (0) log

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.15.138-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor301/3501 is trying to acquire lock:
ffff888024d20460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377

but task is already holding lock:
ffff88801c793860 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x733/0x1d60 security/integrity/ima/ima_main.c:260

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&iint->mutex){+.+.}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       process_measurement+0x733/0x1d60 security/integrity/ima/ima_main.c:260
       ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:519
       do_open fs/namei.c:3540 [inline]
       path_openat+0x2745/0x2f20 fs/namei.c:3672
       do_filp_open+0x21c/0x460 fs/namei.c:3699
       do_sys_openat2+0x13b/0x500 fs/open.c:1211
       do_sys_open fs/open.c:1227 [inline]
       __do_sys_openat fs/open.c:1243 [inline]
       __se_sys_openat fs/open.c:1238 [inline]
       __x64_sys_openat+0x243/0x290 fs/open.c:1238
       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+0x61/0xcb

-> #0 (sb_writers#5){.+.+}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1742 [inline]
       sb_start_write+0x4f/0x1c0 include/linux/fs.h:1812
       mnt_want_write+0x3b/0x80 fs/namespace.c:377
       ovl_maybe_copy_up+0x111/0x180 fs/overlayfs/copy_up.c:1077
       ovl_open+0xa4/0x200 fs/overlayfs/file.c:149
       do_dentry_open+0x807/0xfb0 fs/open.c:826
       vfs_open fs/open.c:956 [inline]
       dentry_open+0xc6/0x120 fs/open.c:972
       ima_calc_file_hash+0x15f/0x1c00 security/integrity/ima/ima_crypto.c:558
       ima_collect_measurement+0x293/0x530 security/integrity/ima/ima_api.c:254
       process_measurement+0x1038/0x1d60 security/integrity/ima/ima_main.c:337
       ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:519
       do_open fs/namei.c:3540 [inline]
       path_openat+0x2745/0x2f20 fs/namei.c:3672
       do_filp_open+0x21c/0x460 fs/namei.c:3699
       do_sys_openat2+0x13b/0x500 fs/open.c:1211
       do_sys_open fs/open.c:1227 [inline]
       __do_sys_open fs/open.c:1235 [inline]
       __se_sys_open fs/open.c:1231 [inline]
       __x64_sys_open+0x221/0x270 fs/open.c:1231
       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+0x61/0xcb

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&iint->mutex);
                               lock(sb_writers#5);
                               lock(&iint->mutex);
  lock(sb_writers#5);

 *** DEADLOCK ***

1 lock held by syz-executor301/3501:
 #0: ffff88801c793860 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x733/0x1d60 security/integrity/ima/ima_main.c:260

stack backtrace:
CPU: 1 PID: 3501 Comm: syz-executor301 Not tainted 5.15.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1742 [inline]
 sb_start_write+0x4f/0x1c0 include/linux/fs.h:1812
 mnt_want_write+0x3b/0x80 fs/namespace.c:377
 ovl_maybe_copy_up+0x111/0x180 fs/overlayfs/copy_up.c:1077
 ovl_open+0xa4/0x200 fs/overlayfs/file.c:149
 do_dentry_open+0x807/0xfb0 fs/open.c:826
 vfs_open fs/open.c:956 [inline]
 dentry_open+0xc6/0x120 fs/open.c:972
 ima_calc_file_hash+0x15f/0x1c00 security/integrity/ima/ima_crypto.c:558
 ima_collect_measurement+0x293/0x530 security/integrity/ima/ima_api.c:254
 process_measurement+0x1038/0x1d60 security/integrity/ima/ima_main.c:337
 ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:519
 do_open fs/namei.c:3540 [inline]
 path_openat+0x2745/0x2f20 fs/namei.c:3672
 do_filp_open+0x21c/0x460 fs/namei.c:3699
 do_sys_openat2+0x13b/0x500 fs/open.c:1211
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_open fs/open.c:1235 [inline]
 __se_sys_open fs/open.c:1231 [inline]
 __x64_sys_open+0x221/0x270 fs/open.c:1231
 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+0x61/0xcb
RIP: 0033:0x7f1244238bf9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 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:00007fff4ff3b868 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f1244238bf9
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000020000180
RBP: 00007f12442ab5f0 R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000001
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (117):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/15 02:56 linux-5.15.y 80529b4968a8 cb976f63 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/03/21 12:20 linux-5.15.y 8020ae3c051d 7939252e .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/08/06 10:54 linux-5.15.y 38d4ca22a528 4ffcc9ef .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/28 11:18 linux-5.15.y 2a910f4af54d 9fe51b7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/27 21:55 linux-5.15.y 2a910f4af54d 7ec6c044 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/27 19:53 linux-5.15.y 2a910f4af54d 7ec6c044 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/27 11:19 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/26 03:36 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/25 11:22 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/25 08:42 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/24 05:45 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/24 01:47 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/23 23:22 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/23 11:10 linux-5.15.y 2a910f4af54d fc59b78e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/23 08:27 linux-5.15.y 2a910f4af54d fc59b78e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/22 23:20 linux-5.15.y 2a910f4af54d 03e12510 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/22 19:47 linux-5.15.y 2a910f4af54d 03e12510 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/22 16:34 linux-5.15.y 2a910f4af54d 03e12510 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/22 07:48 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/21 05:27 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/21 02:21 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/20 19:42 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/20 16:50 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/20 12:22 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/20 11:04 linux-5.15.y 2a910f4af54d cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/20 03:13 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/19 20:38 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/18 16:38 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/18 13:31 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/18 02:52 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/17 17:09 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/17 16:42 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/17 01:13 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/15 16:36 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/15 10:53 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/14 23:31 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/14 01:07 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/13 22:46 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/13 21:29 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/13 11:04 linux-5.15.y 80529b4968a8 6d6dbf8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/13 03:51 linux-5.15.y 80529b4968a8 6d6dbf8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/11 14:35 linux-5.15.y 80529b4968a8 6d6dbf8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/11 03:59 linux-5.15.y 80529b4968a8 d80eec66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/11 01:54 linux-5.15.y 80529b4968a8 d80eec66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/11 00:24 linux-5.15.y 80529b4968a8 d80eec66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/10 23:21 linux-5.15.y 80529b4968a8 d80eec66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/10 19:37 linux-5.15.y 80529b4968a8 45e9b83e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/10 18:35 linux-5.15.y 80529b4968a8 45e9b83e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/04 16:11 linux-5.15.y 12952a23a5da 500bfdc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/11/04 15:06 linux-5.15.y 12952a23a5da 500bfdc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
2023/03/21 10:01 linux-5.15.y 8020ae3c051d 7939252e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in mnt_want_write
* Struck through repros no longer work on HEAD.