Re: [syzbot] [fs?] WARNING in destroy_super_work

From: Hillf Danton

Date: Fri Nov 07 2025 - 03:54:38 EST


> Date: Thu, 06 Nov 2025 23:31:27 -0800
> 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

#syz test

--- x/kernel/nscommon.c
+++ y/kernel/nscommon.c
@@ -117,9 +117,7 @@ struct ns_common *__must_check ns_owner(

void __ns_ref_active_get_owner(struct ns_common *ns)
{
- ns = ns_owner(ns);
- if (ns)
- WARN_ON_ONCE(atomic_add_negative(1, &ns->__ns_ref_active));
+ __ns_ref_active_resurrect(ns);
}

/*
--