syzbot


possible deadlock in f2fs_write_checkpoint

Status: fixed on 2023/02/24 13:50
Subsystems: f2fs
[Documentation on labels]
Reported-by: syzbot+0b9cadf5fc45a98a5083@syzkaller.appspotmail.com
Fix commit: c7f91bd41029 f2fs: Restore rwsem lockdep support
First crash: 809d, last: 759d
Cause bisection: introduced by (bisect log) :
commit e4544b63a7ee49e7fbebf35ece0a6acd3b9617ae
Author: Tim Murray <timmurray@google.com>
Date: Fri Jan 7 20:48:44 2022 +0000

  f2fs: move f2fs to use reader-unfair rwsems

Crash: possible deadlock in f2fs_write_checkpoint (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] possible deadlock in f2fs_write_checkpoint 0 (3) 2022/02/03 02:23

Sample crash report:
F2FS-fs (loop0): Can't find valid F2FS filesystem in 2th superblock
F2FS-fs (loop0): invalid crc_offset: 0
F2FS-fs (loop0): Disable nat_bits due to incorrect cp_ver (13274671252798256465, 0)
F2FS-fs (loop0): Try to recover 2th superblock, ret: 0
F2FS-fs (loop0): Mounted with checkpoint version = 15213551
============================================
WARNING: possible recursive locking detected
5.17.0-rc2-next-20220202-syzkaller #0 Not tainted
--------------------------------------------
syz-executor750/3590 is trying to acquire lock:
ffff88807d0f4390 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2156 [inline]
ffff88807d0f4390 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_write_checkpoint+0x535/0x5c90 fs/f2fs/checkpoint.c:1616

but task is already holding lock:
ffff88807d0f5398 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2156 [inline]
ffff88807d0f5398 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_issue_checkpoint+0x149/0x480 fs/f2fs/checkpoint.c:1835

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&sem->internal_rwsem#2);
  lock(&sem->internal_rwsem#2);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz-executor750/3590:
 #0: ffff88801d7c40e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: deactivate_super+0xa5/0xd0 fs/super.c:362
 #1: ffff88807d0f5398 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2156 [inline]
 #1: ffff88807d0f5398 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_issue_checkpoint+0x149/0x480 fs/f2fs/checkpoint.c:1835

stack backtrace:
CPU: 0 PID: 3590 Comm: syz-executor750 Not tainted 5.17.0-rc2-next-20220202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline]
 check_deadlock kernel/locking/lockdep.c:2999 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027
 lock_acquire kernel/locking/lockdep.c:5639 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
 down_write+0x90/0x150 kernel/locking/rwsem.c:1514
 f2fs_down_write fs/f2fs/f2fs.h:2156 [inline]
 f2fs_write_checkpoint+0x535/0x5c90 fs/f2fs/checkpoint.c:1616
 __write_checkpoint_sync fs/f2fs/checkpoint.c:1746 [inline]
 f2fs_issue_checkpoint+0x156/0x480 fs/f2fs/checkpoint.c:1843
 f2fs_sync_fs+0x20f/0x420 fs/f2fs/super.c:1644
 sync_filesystem.part.0+0x13c/0x1d0 fs/sync.c:66
 sync_filesystem+0x8b/0xc0 fs/sync.c:43
 generic_shutdown_super+0x70/0x400 fs/super.c:445
 kill_block_super+0x97/0xf0 fs/super.c:1394
 kill_f2fs_super+0x2b3/0x3c0 fs/f2fs/super.c:4523
 deactivate_locked_super+0x94/0x160 fs/super.c:332
 deactivate_super+0xad/0xd0 fs/super.c:363
 cleanup_mnt+0x3a2/0x540 fs/namespace.c:1159
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0xb29/0x2b10 kernel/exit.c:806
 do_group_exit+0xd2/0x2f0 kernel/exit.c:935
 __do_sys_exit_group kernel/exit.c:946 [inline]
 __se_sys_exit_group kernel/exit.c:944 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:944
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f62db64d949
Code: Unable to access opcode bytes at RIP 0x7f62db64d91f.
RSP: 002b:00007ffe5daa3ef8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f62db6c3330 RCX: 00007f62db64d949
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 0000000000000000

Crashes (2208):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/02 14:22 linux-next 6abab1b81b65 4ebb2798 .config console log report syz C ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/02 13:33 linux-next 6abab1b81b65 4ebb2798 .config console log report syz C ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/03/01 08:19 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/03/01 00:52 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/28 11:18 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/28 09:26 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/27 16:01 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/27 05:32 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/27 02:36 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/27 02:35 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/26 22:07 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/26 15:03 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/26 11:49 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/26 10:21 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/26 02:31 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/26 00:45 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 23:18 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 21:44 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 20:37 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 20:07 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 18:54 linux-next 196d330d7fb1 45a13a73 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 16:53 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 15:12 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 09:41 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 08:34 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 06:50 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 05:23 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 04:21 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 03:13 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 02:54 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 01:51 linux-next 196d330d7fb1 7c337266 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/25 00:49 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 23:18 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 21:29 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 18:33 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 16:55 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 15:03 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 13:40 linux-next 196d330d7fb1 b28851a4 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 05:51 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 03:05 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/24 00:07 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 22:55 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 13:35 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 12:01 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 09:15 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 07:50 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 06:43 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 05:00 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 03:31 linux-next 196d330d7fb1 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/02/23 01:24 linux-next ef6b35306dd8 6e821dbf .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/01/11 06:18 linux-next 57c149e506d5 ddb0ab8c .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
2022/01/10 09:04 linux-next 57c149e506d5 2ca0d385 .config console log report info ci-upstream-linux-next-kasan-gce-root possible deadlock in f2fs_write_checkpoint
* Struck through repros no longer work on HEAD.