Merge branch 'for-5.5/whiskers' into for-linus

[linux.git] / net / ipv4 / udp.c

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 2cc259736c2e0d10f16dcd5333925e2a369843b9..1d58ce829dcae476a7a32a6ab5fa8bb91ec8ae67 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -388,7 +388,7 @@ static int compute_score(struct sock *sk, struct net *net,
                return -1;
        score += 4;
 
-       if (sk->sk_incoming_cpu == raw_smp_processor_id())
+       if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
                score++;
        return score;
 }
@@ -1316,6 +1316,20 @@ static void udp_set_dev_scratch(struct sk_buff *skb)
                scratch->_tsize_state |= UDP_SKB_IS_STATELESS;
 }
 
+static void udp_skb_csum_unnecessary_set(struct sk_buff *skb)
+{
+       /* We come here after udp_lib_checksum_complete() returned 0.
+        * This means that __skb_checksum_complete() might have
+        * set skb->csum_valid to 1.
+        * On 64bit platforms, we can set csum_unnecessary
+        * to true, but only if the skb is not shared.
+        */
+#if BITS_PER_LONG == 64
+       if (!skb_shared(skb))
+               udp_skb_scratch(skb)->csum_unnecessary = true;
+#endif
+}
+
 static int udp_skb_truesize(struct sk_buff *skb)
 {
        return udp_skb_scratch(skb)->_tsize_state & ~UDP_SKB_IS_STATELESS;
@@ -1550,10 +1564,7 @@ static struct sk_buff *__first_packet_length(struct sock *sk,
                        *total += skb->truesize;
                        kfree_skb(skb);
                } else {
-                       /* the csum related bits could be changed, refresh
-                        * the scratch area
-                        */
-                       udp_set_dev_scratch(skb);
+                       udp_skb_csum_unnecessary_set(skb);
                        break;
                }
        }
@@ -2712,7 +2723,7 @@ __poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait)
        __poll_t mask = datagram_poll(file, sock, wait);
        struct sock *sk = sock->sk;
 
-       if (!skb_queue_empty(&udp_sk(sk)->reader_queue))
+       if (!skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
                mask |= EPOLLIN | EPOLLRDNORM;
 
        /* Check for false positives due to checksum errors */