diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index 98fdcc6f51b1..e7fb7106550f 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -457,8 +457,10 @@ static int mem_check(struct sock *sk)
 	if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
 		return 0;
 
+	rcu_read_lock_bh();
 	for_each_sk_fl_rcu(np, sfl)
 		count++;
+	rcu_read_unlock_bh();
 
 	if (room <= 0 ||
 	    ((count >= FL_MAX_PER_SOCK ||