diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 5015ece7adf7a072d8f8bb636dcf9aad44eb7159..9e9a584cf99343b65574ac545431db9f342f5b53 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -2998,7 +2998,9 @@ static void br_multicast_pim(struct net_bridge *br,
 	    pim_hdr_type(pimhdr) != PIM_TYPE_HELLO)
 		return;
 
+	spin_lock(&br->multicast_lock);
 	br_multicast_mark_router(br, port);
+	spin_unlock(&br->multicast_lock);
 }
 
 static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,