xfrm: flush all states in xfrm_state_fini

[ Upstream commit 42e42562c9cfcdacf000f1b42284a4fad24f8546 ]

While reverting commit f75a2804da39 ("xfrm: destroy xfrm_state
synchronously on net exit path"), I incorrectly changed
xfrm_state_flush's "proto" argument back to IPSEC_PROTO_ANY. This
reverts some of the changes in commit dbb2483b2a46 ("xfrm: clean up
xfrm protocol checks"), and leads to some states not being removed
when we exit the netns.

Pass 0 instead of IPSEC_PROTO_ANY from both xfrm_state_fini
xfrm6_tunnel_net_exit, so that xfrm_state_flush deletes all states.

Fixes: 2a198bbec691 ("Revert "xfrm: destroy xfrm_state synchronously on net exit path"")
Reported-by: syzbot+6641a61fe0e2e89ae8c5@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=6641a61fe0e2e89ae8c5
Tested-by: syzbot+6641a61fe0e2e89ae8c5@syzkaller.appspotmail.com
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>

Author: qsn

net/ipv6/xfrm6_tunnel.c

@@ -344,7 +344,7 @@ static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
 	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
 	unsigned int i;
 
-	xfrm_state_flush(net, IPSEC_PROTO_ANY, false);
+	xfrm_state_flush(net, 0, false);
 	xfrm_flush_gc();
 
 	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)

net/xfrm/xfrm_state.c

@@ -2421,7 +2421,7 @@ void xfrm_state_fini(struct net *net)
 	unsigned int sz;
 
 	flush_work(&net->xfrm.state_hash_work);
-	xfrm_state_flush(net, IPSEC_PROTO_ANY, false);
+	xfrm_state_flush(net, 0, false);
 	flush_work(&xfrm_state_gc_work);
 
 	WARN_ON(!list_empty(&net->xfrm.state_all));