kernel BUG in hfs_write_inode

Status: upstream: reported C repro on 2025/06/16 18:04
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+905e5e4c2be48752878c@syzkaller.appspotmail.com
First crash: 467d, last: 17h19m
Fix commit to backport (bisect log) :
tree: upstream
commit 42b0ef01e6b5e9c77b383d32c25a0ec2a735d08a
Author: Arnd Bergmann <arnd@arndb.de>
Date: Fri Jul 11 08:46:51 2025 +0000

  block: fix FS_IOC_GETLBMD_CAP parsing in blkdev_common_ioctl()

  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2025/08/03 linux-6.6.y (ToT) 3a8ababb8b6a C [report] kernel BUG in hfs_write_inode
2025/06/19 upstream (ToT) fb4d33ab452e C [report] kernel BUG in hfs_write_inode
2025/08/03 upstream (ToT) 186f3edfdd41 C Didn't crash
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 kernel BUG in hfs_write_inode origin:upstream missing-backport -1 syz, C inconclusive 31207 15h25m 1271d 0/3 upstream: reported C repro on 2023/04/04 07:01
linux-4.14 kernel BUG in hfs_write_inode hfs -1 syz, C 3 1301d 1394d 0/1 upstream: reported C repro on 2022/12/02 20:03
linux-4.19 kernel BUG in hfs_write_inode hfs -1 syz, C 24 1300d 1400d 0/1 upstream: reported C repro on 2022/11/26 01:52
linux-5.15 kernel BUG in hfs_write_inode origin:upstream -1 syz, C error 21787 17h00m 1265d 0/3 upstream: reported C repro on 2023/04/10 13:50
upstream kernel BUG in hfs_write_inode prio:high hfs -1 syz, C error 243695 38d 1401d 27/29 upstream: reported C repro on 2022/11/25 09:45
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/12/31 11:28 7h34m fix candidate upstream OK (1) job log

Sample crash report:
wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
------------[ cut here ]------------
kernel BUG at fs/hfs/inode.c:450!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 59 Comm: kworker/u4:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:hfs_write_inode+0x87b/0x880 fs/hfs/inode.c:450
Code: c7 c1 00 53 33 97 80 e1 07 80 c1 03 38 c1 0f 8c 6f fe ff ff 48 c7 c7 00 53 33 97 e8 1f 0e 84 ff e9 5e fe ff ff e8 15 82 2b ff <0f> 0b 0f 1f 00 f3 0f 1e fa 55 41 57 41 56 41 54 53 48 89 fb 49 bf
RSP: 0018:ffffc900015a7340 EFLAGS: 00010293
RAX: ffffffff825c093b RBX: ffff88802bc98ea8 RCX: ffff88801d2a1e00
RDX: 0000000000000000 RSI: ffffffff8d339d40 RDI: 0000000000000000
RBP: ffffc900015a74d0 R08: ffff88801d2a1e00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff920002b4e6c R14: ffff88802bc98e58 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000229bff17a008 CR3: 000000007591e000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 write_inode fs/fs-writeback.c:1534 [inline]
 __writeback_single_inode+0x720/0xee0 fs/fs-writeback.c:1751
 writeback_sb_inodes+0x813/0x1020 fs/fs-writeback.c:1977
 wb_writeback+0x45e/0xbe0 fs/fs-writeback.c:2156
 wb_do_writeback fs/fs-writeback.c:2303 [inline]
 wb_workfn+0x400/0xe60 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:hfs_write_inode+0x87b/0x880 fs/hfs/inode.c:450
Code: c7 c1 00 53 33 97 80 e1 07 80 c1 03 38 c1 0f 8c 6f fe ff ff 48 c7 c7 00 53 33 97 e8 1f 0e 84 ff e9 5e fe ff ff e8 15 82 2b ff <0f> 0b 0f 1f 00 f3 0f 1e fa 55 41 57 41 56 41 54 53 48 89 fb 49 bf
RSP: 0018:ffffc900015a7340 EFLAGS: 00010293
RAX: ffffffff825c093b RBX: ffff88802bc98ea8 RCX: ffff88801d2a1e00
RDX: 0000000000000000 RSI: ffffffff8d339d40 RDI: 0000000000000000
RBP: ffffc900015a74d0 R08: ffff88801d2a1e00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff920002b4e6c R14: ffff88802bc98e58 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000229bfef4a000 CR3: 000000002fefc000 CR4: 00000000003506e0

Crashes (13319):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/25 15:57 linux-6.6.y 79643295eba1 f281d9d2 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/06/16 05:12 linux-6.6.y 924b4a879cbb 50bb0618 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/03/07 12:28 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2025/11/27 07:12 linux-6.6.y 1e89a1be4fe9 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2025/09/26 09:13 linux-6.6.y 147338df3487 0abd0691 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2025/06/17 18:56 linux-6.6.y c2603c511feb cfebc887 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/26 03:35 linux-6.6.y 79643295eba1 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/25 03:53 linux-6.6.y 79643295eba1 f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/24 15:18 linux-6.6.y 79643295eba1 3c3cdf19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/24 02:47 linux-6.6.y 79643295eba1 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/23 11:46 linux-6.6.y 79643295eba1 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/23 11:45 linux-6.6.y 79643295eba1 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/22 21:12 linux-6.6.y 79643295eba1 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/22 07:00 linux-6.6.y 79643295eba1 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/22 05:55 linux-6.6.y 79643295eba1 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/18 09:29 linux-6.6.y 79643295eba1 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/18 08:35 linux-6.6.y 79643295eba1 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/17 23:10 linux-6.6.y 79643295eba1 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/17 18:01 linux-6.6.y 79643295eba1 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/17 00:52 linux-6.6.y 79643295eba1 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/16 23:59 linux-6.6.y 79643295eba1 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/16 05:43 linux-6.6.y 79643295eba1 12a0a44a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/15 15:17 linux-6.6.y 79643295eba1 2daa4bb5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/15 15:13 linux-6.6.y 79643295eba1 2daa4bb5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/14 15:06 linux-6.6.y 79643295eba1 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/12 01:44 linux-6.6.y 8b73de7da85f 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/12 01:41 linux-6.6.y 8b73de7da85f 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/11 13:09 linux-6.6.y 8b73de7da85f b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/11 12:02 linux-6.6.y 8b73de7da85f b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/10 12:35 linux-6.6.y 8b73de7da85f 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/10 11:21 linux-6.6.y 8b73de7da85f 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/09 18:22 linux-6.6.y 8b73de7da85f 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/09 06:22 linux-6.6.y 8b73de7da85f 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/09 05:11 linux-6.6.y 8b73de7da85f 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/09 05:09 linux-6.6.y 8b73de7da85f 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/08 16:17 linux-6.6.y 8b73de7da85f 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/07 17:31 linux-6.6.y 8b73de7da85f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/07 14:10 linux-6.6.y 8b73de7da85f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/07 12:51 linux-6.6.y 8b73de7da85f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/07 12:49 linux-6.6.y 8b73de7da85f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/06 15:22 linux-6.6.y 8b73de7da85f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/06 14:56 linux-6.6.y 8b73de7da85f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/05 03:37 linux-6.6.y 8b73de7da85f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/04 10:20 linux-6.6.y 8b73de7da85f f65209a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/03 21:14 linux-6.6.y 8b73de7da85f 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/03 21:14 linux-6.6.y 8b73de7da85f 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/03 04:38 linux-6.6.y 8b73de7da85f 6a988719 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/02 15:32 linux-6.6.y 8b73de7da85f 85995287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/02 12:58 linux-6.6.y a4a971135a2f 85995287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2025/06/16 18:04 linux-6.6.y c2603c511feb d1716036 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
* Struck through repros no longer work on HEAD.