syzbot


kernel BUG in may_open (3)

Status: upstream: reported C repro on 2026/01/12 08:51
Subsystems: hfs
[Documentation on labels]
Reported-by: syzbot+f98189ed18c1f5f32e00@syzkaller.appspotmail.com
First crash: 5d01h, last: 2d16h
Cause bisection: failed (error log, bisect log)
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH v3] hfsplus: pretend special inodes as regular files 2 (2) 2026/01/13 08:55
[syzbot] [hfs?] kernel BUG in may_open (3) 2 (4) 2026/01/12 10:35
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG in may_open fs -1 C error 137019 189d 285d 29/29 fixed on 2025/07/08 00:33
upstream kernel BUG in may_open (2) fs -1 C done 17716 6d05h 188d 29/29 fixed on 2026/01/07 12:29
Last patch testing requests (1)
Created Duration User Patch Repo Result
2026/01/12 09:31 0m kapoorarnav43@gmail.com patch upstream error

Sample crash report:
loop0: detected capacity change from 0 to 1024
VFS_BUG_ON_INODE(!IS_ANON_FILE(inode)) encountered for inode ffff8880384b01e0
fs hfsplus mode 0 opflags 0x4 flags 0x0 state 0x70 count 2
------------[ cut here ]------------
kernel BUG at fs/namei.c:4210!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 6062 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:may_open+0x4b1/0x4c0 fs/namei.c:4210
Code: 38 c1 0f 8c 1e fd ff ff 4c 89 e7 e8 c9 ec ef ff e9 11 fd ff ff e8 df b3 8d ff 4c 89 f7 48 c7 c6 80 53 f9 8a e8 10 eb f5 fe 90 <0f> 0b 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffc90003ba78e0 EFLAGS: 00010282
RAX: 0000000000000088 RBX: dffffc0000000000 RCX: b41eda36b1e3ff00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000008241 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000774ec1 R12: 0000000000000000
R13: ffffffff8d709d80 R14: ffff8880384b01e0 R15: 0000000000000002
FS:  000055557d7cd500(0000) GS:ffff888126def000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f01916a5890 CR3: 0000000040598000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 do_open fs/namei.c:4635 [inline]
 path_openat+0x32a8/0x3df0 fs/namei.c:4796
 do_filp_open+0x1fa/0x410 fs/namei.c:4823
 do_sys_openat2+0x121/0x200 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_creat fs/open.c:1514 [inline]
 __se_sys_creat fs/open.c:1508 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1508
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f739c0cf749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd4aa21ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f739c325fa0 RCX: 00007f739c0cf749
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000200000000140
RBP: 00007f739c153f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f739c325fa0 R14: 00007f739c325fa0 R15: 0000000000000002
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:may_open+0x4b1/0x4c0 fs/namei.c:4210
Code: 38 c1 0f 8c 1e fd ff ff 4c 89 e7 e8 c9 ec ef ff e9 11 fd ff ff e8 df b3 8d ff 4c 89 f7 48 c7 c6 80 53 f9 8a e8 10 eb f5 fe 90 <0f> 0b 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffc90003ba78e0 EFLAGS: 00010282
RAX: 0000000000000088 RBX: dffffc0000000000 RCX: b41eda36b1e3ff00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000008241 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000774ec1 R12: 0000000000000000
R13: ffffffff8d709d80 R14: ffff8880384b01e0 R15: 0000000000000002
FS:  000055557d7cd500(0000) GS:ffff888126def000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f01916a5890 CR3: 0000000040598000 CR4: 00000000003526f0

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/10 17:36 upstream b6151c4e60e5 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs kernel BUG in may_open
2026/01/10 12:07 upstream 54e82e93ca93 d1b870e1 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root kernel BUG in may_open
2026/01/10 11:23 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in may_open
2026/01/08 08:43 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in may_open
* Struck through repros no longer work on HEAD.