kernel BUG in close_ctree (2)

Status: upstream: reported syz repro on 2025/02/20 01:29
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+1bb366f0586d485d68d5@syzkaller.appspotmail.com
First crash: 520d, last: 30d
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: kernel BUG in close_ctree (log)
Repro: syz .config
  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2025/09/13 linux-6.1.y (ToT) 3db754f56897 syz [report] kernel BUG in close_ctree
2025/05/29 upstream (ToT) 9d230d500b0e syz [report] BUG: MAX_LOCKDEP_CHAINS too low!
2025/09/13 upstream (ToT) 22f20375f5b7 syz Didn't crash
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 kernel BUG in close_ctree missing-backport origin:upstream -1 C done 901 27d 1229d 0/3 upstream: reported C repro on 2023/03/13 21:19
linux-6.1 kernel BUG in close_ctree origin:upstream missing-backport -1 C done 622 563d 1231d 3/3 fixed on 2025/02/10 13:25
upstream kernel BUG in close_ctree btrfs -1 C error error 6653 1d16h 1340d 0/29 upstream: reported C repro on 2022/11/23 08:10
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/12/12 23:57 2h26m fix candidate upstream OK (0) job log
2025/08/14 13:18 3h20m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
BTRFS warning (device loop0): transaction 15 (with 0 dirty metadata bytes) is not committed
assertion failed: !found, in fs/btrfs/disk-io.c:4584
------------[ cut here ]------------
kernel BUG at fs/btrfs/ctree.h:3722!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4407 Comm: syz-executor Not tainted 6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : assertfail+0x28/0x2c fs/btrfs/ctree.h:3721
lr : assertfail+0x28/0x2c fs/btrfs/ctree.h:3721
sp : ffff800020cf77d0
x29: ffff800020cf77d0 x28: ffff800020cf7800 x27: dfff800000000000
x26: ffff0000d82ec540 x25: 1fffe0001b05d8a8 x24: ffff0000d5fda000
x23: ffff0000d5fda028 x22: ffff0000d82ecce8 x21: ffff0000d82ecce8
x20: ffff0000d82ecce8 x19: ffff0000d82ec000 x18: ffff800011a7bd00
x17: 1fffe00033ee7176 x16: ffff8000082d1c1c x15: 0000000040000000
x14: 0000000000000002 x13: 1ffff00002a0e0b1 x12: 0000000000ff0100
x11: ff008000083098d0 x10: 0000000000000000 x9 : a1feadde584d8e00
x8 : a1feadde584d8e00 x7 : ffff8000082516f8 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : ffff80000a83bd8c
x2 : ffff00019f738cd0 x1 : 0000000100000000 x0 : 0000000000000034
Call trace:
 assertfail+0x28/0x2c fs/btrfs/ctree.h:3721
 warn_about_uncommitted_trans fs/btrfs/disk-io.c:4584 [inline]
 close_ctree+0x9a8/0xa64 fs/btrfs/disk-io.c:4772
 btrfs_put_super+0x70/0x80 fs/btrfs/super.c:397
 generic_shutdown_super+0x130/0x324 fs/super.c:501
 kill_anon_super+0x4c/0x80 fs/super.c:1128
 btrfs_kill_super+0x40/0x58 fs/btrfs/super.c:2448
 deactivate_locked_super+0xac/0x124 fs/super.c:332
 deactivate_super+0xe8/0x108 fs/super.c:363
 cleanup_mnt+0x37c/0x404 fs/namespace.c:1186
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193
 task_work_run+0x1ec/0x270 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 do_notify_resume+0x1f70/0x2b0c arch/arm64/kernel/signal.c:1137
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 91178000 90003122 91230042 97ff981f (d4210000) 
---[ end trace 0000000000000000 ]---

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/25 06:32 linux-6.1.y da3c5173c55f ed351ea7 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2026/06/25 08:00 linux-6.1.y fdb6fcb41cc7 cfa969bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in close_ctree
2026/05/02 04:36 linux-6.1.y 4931e0e1673d 753c55b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in close_ctree
2025/09/30 09:16 linux-6.1.y 7b34dc04e4ff 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/09/23 07:53 linux-6.1.y 363a599da6d9 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/08/24 21:37 linux-6.1.y 0bc96de781b4 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/08/16 14:18 linux-6.1.y 0bc96de781b4 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/05/25 03:28 linux-6.1.y da3c5173c55f ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/05/24 08:11 linux-6.1.y da3c5173c55f ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/04/13 16:28 linux-6.1.y 420102835862 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
2025/02/20 01:28 linux-6.1.y 0cbb5f65e52f b257a9b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in close_ctree
* Struck through repros no longer work on HEAD.