diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 6a362da211e1b45aa5e7b94a8085217ab707023f..3504c3acd38f66385e1a64e17d7de8543be94805 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1791,7 +1791,9 @@ 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_multicast_ipv4_rcv(struct net_bridge *br,