ipv6: add complete rcu protection around np->opt

[firefly-linux-kernel-4.4.55.git] / net / ipv6 / syncookies.c

diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index bb8f2fa1c7fbbe1ac0936688ad684ae30679d917..eaf7ac496d506937cd52944bbdc17da720110b59 100644 (file)
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -222,7 +222,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
                memset(&fl6, 0, sizeof(fl6));
                fl6.flowi6_proto = IPPROTO_TCP;
                fl6.daddr = ireq->ir_v6_rmt_addr;
-               final_p = fl6_update_dst(&fl6, np->opt, &final);
+               final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt), &final);
                fl6.saddr = ireq->ir_v6_loc_addr;
                fl6.flowi6_oif = sk->sk_bound_dev_if;
                fl6.flowi6_mark = ireq->ir_mark;