syzbot


kernel BUG in jfs_unlink

Status: upstream: reported C repro on 2026/04/26 03:49
Reported-by: syzbot+61bee673a2dcf3d442d1@syzkaller.appspotmail.com
First crash: 1d12h, last: 1d12h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 kernel BUG in jfs_unlink origin:upstream -1 C error 1 64d 64d 0/2 upstream: reported C repro on 2026/02/22 02:11
upstream kernel BUG in jfs_unlink jfs -1 C inconclusive error 21 25d 641d 0/29 upstream: reported C repro on 2024/07/24 18:05
linux-5.15 kernel BUG in jfs_unlink -1 1 301d 301d 0/3 auto-obsoleted due to no activity on 2025/10/07 19:02

Sample crash report:
BUG at fs/jfs/namei.c:513 assert(ip->i_nlink)
------------[ cut here ]------------
kernel BUG at fs/jfs/namei.c:513!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4419 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : jfs_unlink+0x8ec/0x954 fs/jfs/namei.c:513
lr : jfs_unlink+0x8ec/0x954 fs/jfs/namei.c:513
sp : ffff800020b77a80
x29: ffff800020b77b70 x28: dfff800000000000 x27: ffff70000416ef58
x26: dfff800000000000 x25: ffff800020b77ac0 x24: 0000000000000000
x23: 1ffff00002afad68 x22: ffff0000eab82660 x21: ffff0000eab82930
x20: ffff0000eabb3298 x19: ffff0000eabb3270 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000082d92bc x15: 0000000000000000
x14: 0000000000000001 x13: 1ffff0000416eeb8 x12: 0000000000ff0100
x11: ff00800008311668 x10: 0000000000000000 x9 : 3f48d075f701e500
x8 : 3f48d075f701e500 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800020b77558 x4 : ffff800015304cc0 x3 : ffff80000a891730
x2 : ffff00019f552d10 x1 : 0000000100000000 x0 : 000000000000002d
Call trace:
 jfs_unlink+0x8ec/0x954 fs/jfs/namei.c:513
 vfs_unlink+0x2e0/0x4f4 fs/namei.c:4330
 do_unlinkat+0x328/0x500 fs/namei.c:4398
 __do_sys_unlinkat fs/namei.c:4441 [inline]
 __se_sys_unlinkat fs/namei.c:4434 [inline]
 __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4434
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 90043503 91178063 52804022 959e15d7 (d4210000) 
---[ end trace 0000000000000000 ]---

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/26 03:48 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in jfs_unlink
* Struck through repros no longer work on HEAD.