invalid opcode in hfs_write_inode

Status: closed as dup on 2026/03/23 00:13
Subsystems: hfs
[Documentation on labels]
Reported-by: syzbot+2d1037ba71f644cd9246@syzkaller.appspotmail.com
First crash: 141d, last: 15h19m
Duplicate of
Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported
kernel BUG in hfs_write_inode prio:high hfs -1 syz, C error 238336 now 1351d

Sample crash report:
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 1119 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-7:2)
RIP: 0010:hfs_write_inode+0x95e/0x990 fs/hfs/inode.c:476
Code: 89 de 81 e6 00 00 00 40 31 ff e8 cd 82 19 ff 81 e3 00 00 00 40 75 15 e8 10 7e 19 ff 4c 89 f3 e9 b1 f7 ff ff e8 03 7e 19 ff 90 <0f> 0b e8 fb 7d 19 ff e8 e6 0a 86 fe eb e4 44 89 e1 80 e1 07 80 c1
RSP: 0018:ffffc90005c871a0 EFLAGS: 00010293
RAX: ffffffff82ac4b5d RBX: f8f8f8f8f8f8f8f8 RCX: ffff888024b11f00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90005c87328 R08: ffff888024b11f00 R09: 0000000000000003
R10: 0000000000000100 R11: 0000000000000004 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888062da55b8 R15: 1ffff92000b90e38
FS:  0000000000000000(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc131a95b8 CR3: 000000002bee2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 write_inode fs/fs-writeback.c:1607 [inline]
 __writeback_single_inode+0x6af/0xf90 fs/fs-writeback.c:1850
 writeback_sb_inodes+0x9db/0x1ab0 fs/fs-writeback.c:2079
 wb_writeback+0x41c/0xad0 fs/fs-writeback.c:2264
 wb_do_writeback fs/fs-writeback.c:2432 [inline]
 wb_workfn+0x437/0x10f0 fs/fs-writeback.c:2477
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:hfs_write_inode+0x95e/0x990 fs/hfs/inode.c:476
Code: 89 de 81 e6 00 00 00 40 31 ff e8 cd 82 19 ff 81 e3 00 00 00 40 75 15 e8 10 7e 19 ff 4c 89 f3 e9 b1 f7 ff ff e8 03 7e 19 ff 90 <0f> 0b e8 fb 7d 19 ff e8 e6 0a 86 fe eb e4 44 89 e1 80 e1 07 80 c1
RSP: 0018:ffffc90005c871a0 EFLAGS: 00010293
RAX: ffffffff82ac4b5d RBX: f8f8f8f8f8f8f8f8 RCX: ffff888024b11f00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90005c87328 R08: ffff888024b11f00 R09: 0000000000000003
R10: 0000000000000100 R11: 0000000000000004 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888062da55b8 R15: 1ffff92000b90e38
FS:  0000000000000000(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc131a95b8 CR3: 000000002bee2000 CR4: 00000000003526f0

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/06 20:56 upstream 0d8395707651 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs invalid opcode in hfs_write_inode
2026/03/18 17:50 upstream a989fde763f4 0199f9a1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root invalid opcode in hfs_write_inode
* Struck through repros no longer work on HEAD.