kernel BUG in jffs2_garbage_collect_pass

Status: upstream: reported on 2026/08/10 00:25
Subsystems: jffs2
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+9bbc6788187abbabb2ee@syzkaller.appspotmail.com
First crash: 5d12h, last: 5d12h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
738965a4 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ✅ VMHostTrigger: ❌ kernel BUG in jffs2_garbage_collect_pass 2026/08/09 10:15 2026/08/09 10:15 2026/08/09 10:53 5d63f80b
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [jffs2?] kernel BUG in jffs2_garbage_collect_pass 0 (1) 2026/08/10 00:25

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/jffs2/gc.c:226!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 7620 Comm: jffs2_gcd_mtd0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:jffs2_garbage_collect_pass+0x20e7/0x2170 fs/jffs2/gc.c:226
Code: 6b f7 fd 48 8b 7c 24 20 e8 06 6b 16 08 90 0f 0b e8 de de 95 fe bf 02 00 00 00 e8 34 44 64 fe e9 9d e7 ff ff e8 ca de 95 fe 90 <0f> 0b e8 c2 de 95 fe bf 02 00 00 00 e8 18 44 64 fe e9 7a f8 ff ff
RSP: 0018:ffffc900041b7aa0 EFLAGS: 00010293
RAX: ffffffff832ffa76 RBX: 0000000000000006 RCX: ffff888029738000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900041b7c70 R08: ffff888029738000 R09: 0000000000000006
R10: 0000000000000100 R11: 0000000000000005 R12: ffff8880357c6410
R13: ffff88805f5ef700 R14: 1ffff1100bebdee2 R15: ffff88805f5ef712
FS:  0000000000000000(0000) GS:ffff888125c3e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f06a384fffc CR3: 0000000056094000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 jffs2_garbage_collect_thread+0x634/0x6c0 fs/jffs2/background.c:155
 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:jffs2_garbage_collect_pass+0x20e7/0x2170 fs/jffs2/gc.c:226
Code: 6b f7 fd 48 8b 7c 24 20 e8 06 6b 16 08 90 0f 0b e8 de de 95 fe bf 02 00 00 00 e8 34 44 64 fe e9 9d e7 ff ff e8 ca de 95 fe 90 <0f> 0b e8 c2 de 95 fe bf 02 00 00 00 e8 18 44 64 fe e9 7a f8 ff ff
RSP: 0018:ffffc900041b7aa0 EFLAGS: 00010293
RAX: ffffffff832ffa76 RBX: 0000000000000006 RCX: ffff888029738000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900041b7c70 R08: ffff888029738000 R09: 0000000000000006
R10: 0000000000000100 R11: 0000000000000005 R12: ffff8880357c6410
R13: ffff88805f5ef700 R14: 1ffff1100bebdee2 R15: ffff88805f5ef712
FS:  0000000000000000(0000) GS:ffff888125c3e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f06a384fffc CR3: 0000000056094000 CR4: 00000000003526f0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/04 23:46 upstream 562bfb501c54 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in jffs2_garbage_collect_pass
* Struck through repros no longer work on HEAD.