WARNING in __btrfs_unlink_inode

Status: upstream: reported C repro on 2024/09/17 14:28
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+c80d64708c6855389daa@syzkaller.appspotmail.com
First crash: 709d, last: 45d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/09/18 upstream (ToT) 2f27fce67173 C [report] BUG: MAX_LOCKDEP_KEYS too low!
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING in __btrfs_unlink_inode -1 syz, C 2 1269d 1269d 0/1 upstream: reported C repro on 2023/03/07 06:13
linux-4.14 WARNING in __btrfs_unlink_inode -1 syz, C 1 1269d 1269d 0/1 upstream: reported C repro on 2023/03/07 07:22
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/07/13 00:45 16m retest repro linux-5.15.y report log
2026/07/13 00:45 20m retest repro linux-5.15.y report log
2026/05/30 15:02 17m retest repro linux-5.15.y report log
2026/04/26 21:32 23m retest repro linux-5.15.y report log
2026/04/26 21:32 16m retest repro linux-5.15.y report log
2026/03/17 23:20 10m retest repro linux-5.15.y report log
2026/02/14 13:41 17m retest repro linux-5.15.y report log
2026/02/14 13:41 14m retest repro linux-5.15.y report log
2026/01/06 20:42 11m retest repro linux-5.15.y report log
2025/12/05 17:56 14m retest repro linux-5.15.y error

Sample crash report:
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4088 at fs/btrfs/inode.c:4167 __btrfs_unlink_inode+0x950/0xb3c fs/btrfs/inode.c:4167
Modules linked in:
CPU: 1 PID: 4088 Comm: syz-executor190 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __btrfs_unlink_inode+0x950/0xb3c fs/btrfs/inode.c:4167
lr : __btrfs_unlink_inode+0x950/0xb3c fs/btrfs/inode.c:4167
sp : ffff80001fd779c0
x29: ffff80001fd77a60 x28: ffff80001fd77a20 x27: 1ffff00003faef40
x26: 0000000000000104 x25: 00000000fffffff4 x24: ffff0000d1286f20
x23: ffff0000e1c7b6e0 x22: 1ffff00003faef44 x21: dfff800000000000
x20: 1fffe0001c38f6e7 x19: ffff0000e1c7b738 x18: 0000000000000001
x17: 0000000000000000 x16: ffff800011ac23e0 x15: 00000000ffffffff
x14: ffff0000cdde9b40 x13: 0000000000000001 x12: 0000000000000001
x11: 0000000000000000 x10: 0000000000000000 x9 : 651006df514f2700
x8 : 651006df514f2700 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff80001fd77138 x4 : ffff800014b9fae0 x3 : ffff800008557c4c
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000026
Call trace:
 __btrfs_unlink_inode+0x950/0xb3c fs/btrfs/inode.c:4167
 btrfs_unlink_inode fs/btrfs/inode.c:4215 [inline]
 btrfs_unlink+0x10c/0x254 fs/btrfs/inode.c:4258
 vfs_unlink+0x2f0/0x508 fs/namei.c:4280
 do_unlinkat+0x4cc/0x830 fs/namei.c:4348
 __do_sys_unlinkat fs/namei.c:4391 [inline]
 __se_sys_unlinkat fs/namei.c:4384 [inline]
 __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4384
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
irq event stamp: 72454
hardirqs last  enabled at (72453): [<ffff80000832c17c>] __up_console_sem+0xb4/0x100 kernel/printk/printk.c:257
hardirqs last disabled at (72454): [<ffff800011abda6c>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:396
softirqs last  enabled at (72434): [<ffff8000081b6d74>] softirq_handle_end kernel/softirq.c:401 [inline]
softirqs last  enabled at (72434): [<ffff8000081b6d74>] handle_softirqs+0xb88/0xdbc kernel/softirq.c:586
softirqs last disabled at (72425): [<ffff8000081b740c>] __do_softirq kernel/softirq.c:592 [inline]
softirqs last disabled at (72425): [<ffff8000081b740c>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
softirqs last disabled at (72425): [<ffff8000081b740c>] invoke_softirq kernel/softirq.c:439 [inline]
softirqs last disabled at (72425): [<ffff8000081b740c>] __irq_exit_rcu+0x268/0x4d8 kernel/softirq.c:641
---[ end trace c8ead0aec9c69578 ]---
BTRFS: error (device loop0) in __btrfs_unlink_inode:4167: errno=-12 Out of memory
BTRFS info (device loop0): forced readonly

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/17 16:31 linux-5.15.y 3a5928702e71 c673ca06 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in __btrfs_unlink_inode
2024/09/17 15:52 linux-5.15.y 3a5928702e71 c673ca06 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in __btrfs_unlink_inode
2024/09/17 15:06 linux-5.15.y 3a5928702e71 c673ca06 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in __btrfs_unlink_inode
2024/09/17 14:27 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in __btrfs_unlink_inode
* Struck through repros no longer work on HEAD.