Re: [syzbot] [net?] WARNING in xfrm_state_fini (3)

[Hillf Danton <hdanton@sina.com>]

> Date: Tue, 29 Jul 2025 00:08:31 -0700	[thread overview]
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    038d61fd6422 Linux 6.16
> git tree:       upstream
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=11b88cf0580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=4066f1c76cfbc4fe
> dashboard link: https://syzkaller.appspot.com/bug?extid=6641a61fe0e2e89ae8c5
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16ca1782580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=140194a2580000

#syz test

--- x/net/xfrm/xfrm_state.c
+++ y/net/xfrm/xfrm_state.c
@@ -615,6 +615,15 @@ static void xfrm_state_gc_destroy(struct
 		put_page(x->xfrag.page);
 	xfrm_dev_state_free(x);
 	security_xfrm_state_free(x);
+	spin_lock_bh(&x->lock);
+	do {
+		struct net *net = xs_net(x);
+
+		spin_lock(&net->xfrm.xfrm_state_lock);
+		list_del_init(&x->km.all);
+		spin_unlock(&net->xfrm.xfrm_state_lock);
+	} while (0);
+	spin_unlock_bh(&x->lock);
 	xfrm_state_free(x);
 }
 
@@ -816,7 +825,7 @@ int __xfrm_state_delete(struct xfrm_stat
 		x->km.state = XFRM_STATE_DEAD;
 
 		spin_lock(&net->xfrm.xfrm_state_lock);
-		list_del(&x->km.all);
+		list_del_init(&x->km.all);
 		hlist_del_rcu(&x->bydst);
 		hlist_del_rcu(&x->bysrc);
 		if (x->km.seq)
--