[v5.15] WARNING in hfsplus_ext_write_extent

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3dea0e7f549e Linux 5.15.186
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10d81982580000
kernel config: https://syzkaller.appspot.com/x/.config?x=918afca6cf85eccf
dashboard link: https://syzkaller.appspot.com/bug?extid=572568f0434ef417c5fb
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b4e974189c3a/disk-3dea0e7f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/922e99f38be2/vmlinux-3dea0e7f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/59456f23f37e/bzImage-3dea0e7f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+572568...@syzkaller.appspotmail.com

------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: CPU: 1 PID: 4477 at kernel/locking/mutex.c:575 __mutex_lock_common+0x18fa/0x2390 kernel/locking/mutex.c:-1
Modules linked in:

CPU: 1 PID: 4477 Comm: kworker/u4:6 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: writeback wb_workfn
(flush-7:1)
RIP: 0010:__mutex_lock_common+0x18fa/0x2390 kernel/locking/mutex.c:575
Code: 00 48 8d bc 24 e0 00 00 00 0f 85 47 e8 ff ff 48 c7 c7 c0 00 0b 8a 48 c7 c6 00 01 0b 8a e8 8e bb ec ff 48 8d bc 24 e0 00 00 00 <0f> 0b e9 25 e8 ff ff e8 0a 5e 56 f7 e9 df fb ff ff 0f 0b e9 2d f0
RSP: 0018:ffffc900031df240 EFLAGS: 00010246
RAX: bc633d967bc62700 RBX: ffffffff8229fed7 RCX: ffff88801d65bb80
RDX: 0000000000000000 RSI: 0000000080000000 RDI: ffffc900031df320
RBP: ffffc900031df3e0 R08: dffffc0000000000 R09: ffffed1017224f24
R10: ffffed1017224f24 R11: 1ffff11017224f23 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88806b3321a0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6b31952000 CR3: 0000000079bc6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
hfsplus_ext_write_extent+0x87/0x200 fs/hfsplus/extents.c:149
hfsplus_write_inode+0x1e/0x5b0 fs/hfsplus/super.c:154
write_inode fs/fs-writeback.c:1495 [inline]
__writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1705
writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1930
wb_writeback+0x443/0xb90 fs/fs-writeback.c:2104
wb_do_writeback fs/fs-writeback.c:2247 [inline]
wb_workfn+0x423/0xe60 fs/fs-writeback.c:2288
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.