sctp: fix return value check in __sctp_rcv_asconf_lookup

stable inclusion
from linux-4.19.201
commit d9b6f0a200bef5fb9ba00e4e7d0d51f0b0fa5c6f

--------------------------------

[ Upstream commit 557fb586 ]

As Ben Hutchings noticed, this check should have been inverted: the call
returns true in case of success.
Reported-by: NBen Hutchings <ben@decadent.org.uk>
Fixes: 0c5dc070 ("sctp: validate from_addr_param return")
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

net/sctp/input.c

@@ -1135,7 +1135,7 @@ static struct sctp_association *__sctp_rcv_asconf_lookup(
 	if (unlikely(!af))
 		return NULL;
 
-	if (af->from_addr_param(&paddr, param, peer_port, 0))
+	if (!af->from_addr_param(&paddr, param, peer_port, 0))
 		return NULL;
 
 	return __sctp_lookup_association(net, laddr, &paddr, transportp);