syzbot


WARNING in jfs_rmdir

Status: upstream: reported on 2026/07/15 15:55
Subsystems: jfs
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+25d73e804a7282b9e58c@syzkaller.appspotmail.com
First crash: 4d15h, last: 4d15h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
77d46f14-1811-442a-b836-fd54fc45dd03 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in jfs_rmdir 2026/07/13 01:04 2026/07/13 01:04 2026/07/13 01:59 d78ea535f456172a095a6d211ee0a2de1d049968

			
		
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [jfs?] WARNING in jfs_rmdir 0 (1) 2026/07/15 15:55

Sample crash report:
------------[ cut here ]------------
inode->i_nlink == 0
WARNING: fs/inode.c:408 at drop_nlink+0xc5/0x110 fs/inode.c:408, CPU#1: syz-executor/5601
Modules linked in:
CPU: 1 UID: 0 PID: 5601 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:drop_nlink+0xc5/0x110 fs/inode.c:408
Code: 40 09 00 00 be 08 00 00 00 e8 37 32 ea ff f0 48 ff 83 40 09 00 00 5b 41 5c 41 5e 41 5f 5d e9 92 28 01 09 cc e8 ec c2 80 ff 90 <0f> 0b 90 eb 81 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 5b ff ff ff
RSP: 0018:ffffc90004effc30 EFLAGS: 00010293
RAX: ffffffff82447654 RBX: ffff888060720440 RCX: ffff88803789be00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f5efdf R12: 1ffff1100c0e4091
R13: dffffc0000000000 R14: ffff888060720488 R15: dffffc0000000000
FS:  000055557213a500(0000) GS:ffff888125d49000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd1d9243000 CR3: 00000000555fe000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 inode_dec_link_count include/linux/fs.h:2262 [inline]
 jfs_rmdir+0x416/0x850 fs/jfs/namei.c:395
 vfs_rmdir+0x3e9/0x6b0 fs/namei.c:5381
 filename_rmdir+0x292/0x520 fs/namei.c:5438
 __do_sys_unlinkat fs/namei.c:5613 [inline]
 __se_sys_unlinkat+0x71/0x1a0 fs/namei.c:5606
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1f4f15cf77
Code: 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 07 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcc0c7a848 EFLAGS: 00000207 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f1f4f15cf77
RDX: 0000000000000200 RSI: 00007ffcc0c7b9f0 RDI: 00000000ffffff9c
RBP: 00007f1f4f1f32ca R08: 0000000000008560 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000207 R12: 00007ffcc0c7b9f0
R13: 00007f1f4f1f32ca R14: 0000000000043463 R15: 00007ffcc0c7dbb0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/11 15:46 upstream 61c03dfde854 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in jfs_rmdir
* Struck through repros no longer work on HEAD.