From: syzbot <syzbot+1957b26299cf3ff7890c@syzkaller.appspotmail.com>
To: Liam.Howlett@oracle.com, akpm@linux-foundation.org,
anna-maria@linutronix.de, bpf@vger.kernel.org,
brauner@kernel.org, bsegall@google.com, cgroups@vger.kernel.org,
david@redhat.com, dietmar.eggemann@arm.com, frederic@kernel.org,
hannes@cmpxchg.org, jack@suse.cz, jsavitz@redhat.com,
juri.lelli@redhat.com, kees@kernel.org,
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lorenzo.stoakes@oracle.com, mgorman@suse.de, mhocko@suse.com,
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oleg@redhat.com, paul@paul-moore.com, peterz@infradead.org,
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surenb@google.com, syzkaller-bugs@googlegroups.com,
tglx@linutronix.de, tj@kernel.org, vbabka@suse.cz,
vincent.guittot@linaro.org, viro@zeniv.linux.org.uk,
vschneid@redhat.com
Subject: [syzbot] [fs?] WARNING in destroy_super_work
Date: Thu, 06 Nov 2025 23:31:27 -0800 [thread overview]
Message-ID: <690da04f.a70a0220.22f260.0027.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 982312090977 Add linux-next specific files for 20251103
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17b2932f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=43cc0e31558cb527
dashboard link: https://syzkaller.appspot.com/bug?extid=1957b26299cf3ff7890c
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1347817c580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/40058f8a830c/disk-98231209.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1d7f42e8639f/vmlinux-98231209.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d8bb0284f393/bzImage-98231209.xz
The issue was bisected to:
commit 3c9820d5c64aeaadea7ffe3a6bb99d019a5ff46a
Author: Christian Brauner <brauner@kernel.org>
Date: Wed Oct 29 12:20:24 2025 +0000
ns: add active reference count
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=101e9bcd980000
final oops: https://syzkaller.appspot.com/x/report.txt?x=121e9bcd980000
console output: https://syzkaller.appspot.com/x/log.txt?x=141e9bcd980000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1957b26299cf3ff7890c@syzkaller.appspotmail.com
Fixes: 3c9820d5c64a ("ns: add active reference count")
------------[ cut here ]------------
WARNING: ./include/linux/ns_common.h:229 at __ns_ref_put include/linux/ns_common.h:229 [inline], CPU#0: kworker/0:6/6108
WARNING: ./include/linux/ns_common.h:229 at put_user_ns include/linux/user_namespace.h:189 [inline], CPU#0: kworker/0:6/6108
WARNING: ./include/linux/ns_common.h:229 at destroy_super_work+0x15c/0x1a0 fs/super.c:280, CPU#0: kworker/0:6/6108
Modules linked in:
CPU: 0 UID: 0 PID: 6108 Comm: kworker/0:6 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events destroy_super_work
RIP: 0010:__ns_ref_put include/linux/ns_common.h:229 [inline]
RIP: 0010:put_user_ns include/linux/user_namespace.h:189 [inline]
RIP: 0010:destroy_super_work+0x15c/0x1a0 fs/super.c:280
Code: 90 63 ff 48 81 c3 a8 fc ff ff 48 89 df e8 ec 90 63 ff 4c 89 f7 5b 41 5c 41 5d 41 5e 41 5f 5d e9 8a 91 e1 ff e8 45 df 86 ff 90 <0f> 0b 90 e9 6d ff ff ff e8 37 df 86 ff 4c 89 e7 be 03 00 00 00 e8
RSP: 0018:ffffc900030d7a48 EFLAGS: 00010293
RAX: ffffffff823a294b RBX: ffff88805639c898 RCX: ffff88802ab59e80
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: 0000000000000004 R08: ffff88807477565b R09: 1ffff1100e8eeacb
R10: dffffc0000000000 R11: ffffed100e8eeacc R12: ffff888074775658
R13: dffffc0000000000 R14: ffff88805639c000 R15: ffff8880747754c8
FS: 0000000000000000(0000) GS:ffff888125eda000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c008044000 CR3: 0000000077ad4000 CR4: 00000000003526f0
Call Trace:
<TASK>
process_one_work+0x94a/0x15d0 kernel/workqueue.c:3267
process_scheduled_works kernel/workqueue.c:3350 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3431
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x52d/0xa70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
---
This report is generated by a bot. It may contain errors.
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
If the report is already addressed, let syzbot know by replying with:
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next reply other threads:[~2025-11-07 7:31 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-07 7:31 syzbot [this message]
2025-11-09 13:39 ` Christian Brauner
2025-11-09 14:11 ` syzbot
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