syzbot


WARNING in hfsplus_ext_write_extent (2)

Status: upstream: reported on 2025/10/21 02:49
Reported-by: syzbot+45009b00c9c1b0c8af51@syzkaller.appspotmail.com
First crash: 25d, last: 25d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in hfsplus_ext_write_extent (2) hfs -1 1 695d 694d 0/29 auto-obsoleted due to no activity on 2024/03/29 06:17
linux-5.15 WARNING in hfsplus_ext_write_extent -1 2 127d 137d 0/3 auto-obsoleted due to no activity on 2025/10/18 16:49
upstream WARNING in hfsplus_ext_write_extent hfs -1 26 823d 1082d 0/29 auto-obsoleted due to no activity on 2023/11/22 16:42
linux-6.1 WARNING in hfsplus_ext_write_extent -1 1 930d 930d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:09

Sample crash report:
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: CPU: 1 PID: 3391 at kernel/locking/mutex.c:582 __mutex_lock_common kernel/locking/mutex.c:582 [inline]
WARNING: CPU: 1 PID: 3391 at kernel/locking/mutex.c:582 __mutex_lock+0xa24/0xaf0 kernel/locking/mutex.c:747
Modules linked in:
CPU: 1 PID: 3391 Comm: kworker/u4:9 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: writeback wb_workfn (flush-7:3)
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline]
RIP: 0010:__mutex_lock+0xa24/0xaf0 kernel/locking/mutex.c:747
Code: 04 28 84 c0 0f 85 b7 00 00 00 83 3d 2d dc fe 03 00 0f 85 e0 f6 ff ff 48 c7 c7 00 f0 8b 8a 48 c7 c6 a0 f0 8b 8a e8 ec 35 2c f7 <0f> 0b e9 c6 f6 ff ff 0f 0b e9 6c f9 ff ff 48 c7 c1 40 91 be 96 80
RSP: 0018:ffffc90005347280 EFLAGS: 00010246
RAX: ae0f951b1b8ac700 RBX: ffff888071acd000 RCX: ffff88804b000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc900053473d0 R08: dffffc0000000000 R09: ffffed10171e4f34
R10: ffffed10171e4f34 R11: 1ffff110171e4f33 R12: 0000000000000000
R13: dffffc0000000000 R14: 1ffff92000a68e80 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555638755c8 CR3: 0000000036e57000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 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:1470 [inline]
 __writeback_single_inode+0x75b/0x1160 fs/fs-writeback.c:1687
 writeback_sb_inodes+0xad8/0x17d0 fs/fs-writeback.c:1913
 wb_writeback+0x468/0xd00 fs/fs-writeback.c:2087
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x435/0xec0 fs/fs-writeback.c:2270
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/21 02:49 linux-6.1.y 8e6e2188d949 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in hfsplus_ext_write_extent
* Struck through repros no longer work on HEAD.