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: 445d, last: 43m
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 30606 4h00m 1249d 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 1279d 1372d 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 1278d 1379d 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 21614 5h09m 1243d 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 17d 1379d 26/29 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: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
------------[ cut here ]------------
kernel BUG at fs/hfs/inode.c:449!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 1135 Comm: kworker/u4:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:hfs_write_inode+0x87a/0x880 fs/hfs/inode.c:449
Code: c7 c1 00 73 31 97 80 e1 07 80 c1 03 38 c1 0f 8c 73 fe ff ff 48 c7 c7 00 73 31 97 e8 f0 f2 83 ff e9 62 fe ff ff e8 e6 b2 2b ff <0f> 0b 0f 1f 40 00 f3 0f 1e fa 55 41 57 41 56 41 54 53 48 89 fb 49
RSP: 0018:ffffc9000490f340 EFLAGS: 00010293
RAX: ffffffff825b78aa RBX: ffff88802d728ea8 RCX: ffff888023f81e00
RDX: 0000000000000000 RSI: ffffffff8d33a040 RDI: 0000000000000000
RBP: ffffc9000490f4d0 R08: ffff888023f81e00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff92000921e6c R14: ffff88802d728e58 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557e130a38 CR3: 0000000031225000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 write_inode fs/fs-writeback.c:1483 [inline]
 __writeback_single_inode+0x705/0xec0 fs/fs-writeback.c:1700
 writeback_sb_inodes+0x7cd/0xf50 fs/fs-writeback.c:1926
 wb_writeback+0x46a/0xbf0 fs/fs-writeback.c:2105
 wb_do_writeback fs/fs-writeback.c:2252 [inline]
 wb_workfn+0x400/0xe60 fs/fs-writeback.c:2292
 process_one_work kernel/workqueue.c:2653 [inline]
 process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
 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+0x87a/0x880 fs/hfs/inode.c:449
Code: c7 c1 00 73 31 97 80 e1 07 80 c1 03 38 c1 0f 8c 73 fe ff ff 48 c7 c7 00 73 31 97 e8 f0 f2 83 ff e9 62 fe ff ff e8 e6 b2 2b ff <0f> 0b 0f 1f 40 00 f3 0f 1e fa 55 41 57 41 56 41 54 53 48 89 fb 49
RSP: 0018:ffffc9000490f340 EFLAGS: 00010293
RAX: ffffffff825b78aa RBX: ffff88802d728ea8 RCX: ffff888023f81e00
RDX: 0000000000000000 RSI: ffffffff8d33a040 RDI: 0000000000000000
RBP: ffffc9000490f4d0 R08: ffff888023f81e00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff92000921e6c R14: ffff88802d728e58 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557e130a38 CR3: 00000000309a8000 CR4: 00000000003506e0

Crashes (13131):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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
2026/09/05 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
2026/09/01 11:35 linux-6.6.y a4a971135a2f 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/09/01 11:35 linux-6.6.y a4a971135a2f 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/31 16:42 linux-6.6.y a4a971135a2f 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/28 21:18 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/28 08:36 linux-6.6.y a4a971135a2f e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/27 13:57 linux-6.6.y 93e0c9521fa8 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/27 10:45 linux-6.6.y dc6160265ffc 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/27 10:45 linux-6.6.y dc6160265ffc 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/26 13:29 linux-6.6.y dc6160265ffc a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/26 01:09 linux-6.6.y dc6160265ffc 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/25 12:06 linux-6.6.y dc6160265ffc a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/24 23:39 linux-6.6.y dc6160265ffc 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/24 11:21 linux-6.6.y dc6160265ffc b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/23 15:02 linux-6.6.y dc6160265ffc 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/19 17:52 linux-6.6.y c610b395b0a5 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/18 03:04 linux-6.6.y d27334b2888c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/17 23:58 linux-6.6.y d27334b2888c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/17 11:24 linux-6.6.y d27334b2888c 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/17 01:44 linux-6.6.y d27334b2888c 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/15 20:10 linux-6.6.y d27334b2888c 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/15 02:05 linux-6.6.y d27334b2888c 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/14 13:46 linux-6.6.y d27334b2888c 6f9b3e89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/14 13:37 linux-6.6.y d27334b2888c 6f9b3e89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/14 01:17 linux-6.6.y d27334b2888c b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/13 19:35 linux-6.6.y d27334b2888c b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/13 07:52 linux-6.6.y d27334b2888c 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 21:14 linux-6.6.y d27334b2888c 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 21:14 linux-6.6.y d27334b2888c 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 20:13 linux-6.6.y d27334b2888c 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 09:22 linux-6.6.y d27334b2888c f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 05:03 linux-6.6.y d27334b2888c f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 05:03 linux-6.6.y d27334b2888c f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/12 03:51 linux-6.6.y d27334b2888c f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/11 22:49 linux-6.6.y d27334b2888c 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/11 16:27 linux-6.6.y d27334b2888c 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/11 15:15 linux-6.6.y d27334b2888c 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in hfs_write_inode
2026/08/11 15:15 linux-6.6.y d27334b2888c 71790083 .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.