syzbot


possible deadlock in ext4_bmap

Status: upstream: reported C repro on 2023/03/07 16:42
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+5bc75b63c58b40e14b5b@syzkaller.appspotmail.com
First crash: 403d, last: 6m
Bug presence (2)
Date Name Commit Repro Result
2023/05/03 linux-5.15.y (ToT) 8a7f2a5c5aa1 C [report] possible deadlock in ext4_bmap
2023/05/03 upstream (ToT) 348551ddaf31 C Didn't crash
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in ext4_bmap origin:lts-only C done 19903 1h30m 403d 0/3 upstream: reported C repro on 2023/03/07 17:07
upstream possible deadlock in ext4_bmap ext4 C error 78083 310d 614d 22/26 fixed on 2023/06/08 14:41
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2023/10/06 13:30 1h55m fix candidate upstream job log (0)

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.15.146-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor160/3499 is trying to acquire lock:
ffff888019ff03f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:797 [inline]
ffff888019ff03f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3152

but task is already holding lock:
ffff88814b2983f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x31c/0xc90 fs/jbd2/journal.c:2476

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&journal->j_checkpoint_mutex){+.+.}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
       mutex_lock_io_nested+0x45/0x60 kernel/locking/mutex.c:777
       jbd2_journal_flush+0x290/0xc90 fs/jbd2/journal.c:2466
       ext4_ioctl_checkpoint fs/ext4/ioctl.c:849 [inline]
       __ext4_ioctl fs/ext4/ioctl.c:1267 [inline]
       ext4_ioctl+0x3249/0x5b80 fs/ext4/ioctl.c:1276
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:874 [inline]
       __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
       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

-> #2 (&journal->j_barrier){+.+.}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __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
       jbd2_journal_lock_updates+0x2aa/0x370 fs/jbd2/transaction.c:905
       ext4_change_inode_journal_flag+0x1a8/0x6e0 fs/ext4/inode.c:6041
       ext4_ioctl_setflags fs/ext4/ioctl.c:448 [inline]
       ext4_fileattr_set+0xdf4/0x1750 fs/ext4/ioctl.c:765
       vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:700
       ioctl_setflags fs/ioctl.c:732 [inline]
       do_vfs_ioctl+0x1d85/0x2b70 fs/ioctl.c:843
       __do_sys_ioctl fs/ioctl.c:872 [inline]
       __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860
       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

-> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       percpu_down_write+0x52/0x2d0 kernel/locking/percpu-rwsem.c:217
       ext4_ind_migrate+0x254/0x760 fs/ext4/migrate.c:625
       ext4_ioctl_setflags fs/ext4/ioctl.c:457 [inline]
       ext4_fileattr_set+0xe8b/0x1750 fs/ext4/ioctl.c:765
       vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:700
       ioctl_setflags fs/ioctl.c:732 [inline]
       do_vfs_ioctl+0x1d85/0x2b70 fs/ioctl.c:843
       __do_sys_ioctl fs/ioctl.c:872 [inline]
       __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860
       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->s_type->i_mutex_key#9){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1488
       inode_lock_shared include/linux/fs.h:797 [inline]
       ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3152
       bmap+0xa1/0xd0 fs/inode.c:1756
       jbd2_journal_bmap fs/jbd2/journal.c:980 [inline]
       __jbd2_journal_erase fs/jbd2/journal.c:1788 [inline]
       jbd2_journal_flush+0x7a2/0xc90 fs/jbd2/journal.c:2494
       ext4_ioctl_checkpoint fs/ext4/ioctl.c:849 [inline]
       __ext4_ioctl fs/ext4/ioctl.c:1267 [inline]
       ext4_ioctl+0x3249/0x5b80 fs/ext4/ioctl.c:1276
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:874 [inline]
       __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
       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:

Chain exists of:
  &sb->s_type->i_mutex_key#9 --> &journal->j_barrier --> &journal->j_checkpoint_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&journal->j_checkpoint_mutex);
                               lock(&journal->j_barrier);
                               lock(&journal->j_checkpoint_mutex);
  lock(&sb->s_type->i_mutex_key#9);

 *** DEADLOCK ***

2 locks held by syz-executor160/3499:
 #0: ffff88814b298170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x2aa/0x370 fs/jbd2/transaction.c:905
 #1: ffff88814b2983f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x31c/0xc90 fs/jbd2/journal.c:2476

stack backtrace:
CPU: 1 PID: 3499 Comm: syz-executor160 Not tainted 5.15.146-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1488
 inode_lock_shared include/linux/fs.h:797 [inline]
 ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3152
 bmap+0xa1/0xd0 fs/inode.c:1756
 jbd2_journal_bmap fs/jbd2/journal.c:980 [inline]
 __jbd2_journal_erase fs/jbd2/journal.c:1788 [inline]
 jbd2_journal_flush+0x7a2/0xc90 fs/jbd2/journal.c:2494
 ext4_ioctl_checkpoint fs/ext4/ioctl.c:849 [inline]
 __ext4_ioctl fs/ext4/ioctl.c:1267 [inline]
 ext4_ioctl+0x3249/0x5b80 fs/ext4/ioctl.c:1276
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 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: 0033:0x7f548f666329
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc37a59968 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffc37a59b38 RCX: 00007f548f666329
RDX: 00000000200005c0 RSI: 000000004004662b RDI: 0000000000000004
RBP: 00007f548f6d9610 R08: 00007ffc37a59b38 R09: 00007ffc37a59b38
R10: 00007ffc37a59b38 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc37a59b28 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (19857):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/10 06:54 linux-5.15.y 26c690eff0a5 b438bd66 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2023/10/29 10:29 linux-5.15.y 12952a23a5da 3c418d72 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2023/03/10 04:12 linux-5.15.y d9b4a0c83a2d f08b59ac .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ext4_bmap
2023/08/22 04:18 linux-5.15.y f6f7927ac664 6b415825 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2023/06/24 05:18 linux-5.15.y f67653019430 79782afc .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ext4_bmap
2023/06/18 05:54 linux-5.15.y 471e639e59d1 f3921d4d .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2023/03/08 01:37 linux-5.15.y d9b4a0c83a2d d7ea8bc4 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ext4_bmap
2024/04/13 23:07 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 22:00 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 20:50 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 19:40 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 18:00 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 17:17 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 16:09 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ext4_bmap
2024/04/13 14:11 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 12:45 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 11:00 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 10:49 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 09:45 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 08:33 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 08:17 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 07:14 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 05:20 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 04:48 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 03:44 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 02:18 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 21:45 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 20:47 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 19:40 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 17:58 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 17:19 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ext4_bmap
2024/04/12 16:12 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 14:54 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 14:07 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 13:04 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 12:38 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 11:36 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 10:20 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 10:09 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 09:00 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 08:00 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 07:19 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 06:16 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 06:03 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 04:58 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 03:33 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 03:11 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 02:08 linux-5.15.y cdfd0a7f0139 27de0a5c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 01:00 linux-5.15.y cdfd0a7f0139 95ed9ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/12 00:06 linux-5.15.y cdfd0a7f0139 95ed9ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/11 22:48 linux-5.15.y cdfd0a7f0139 95ed9ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
2024/04/13 14:52 linux-5.15.y fa3df276cd36 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ext4_bmap
2023/03/07 16:42 linux-5.15.y d9b4a0c83a2d d7ea8bc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in ext4_bmap
* Struck through repros no longer work on HEAD.