1 files changed, 24 insertions, 12 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 13d868c43284..b3f34e366b27 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1182,7 +1182,7 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
 		if (!md5sig)
 			return -ENOMEM;
 
-		sk_nocaps_add(sk, NETIF_F_GSO_MASK);
+		sk_gso_disable(sk);
 		INIT_HLIST_HEAD(&md5sig->head);
 		rcu_assign_pointer(tp->md5sig_info, md5sig);
 	}
@@ -1620,7 +1620,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
 		 */
 		tcp_md5_do_add(newsk, addr, AF_INET, 32, l3index, key->flags,
 			       key->key, key->keylen, GFP_ATOMIC);
-		sk_nocaps_add(newsk, NETIF_F_GSO_MASK);
+		sk_gso_disable(newsk);
 	}
 #endif
 
@@ -1701,7 +1701,10 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 	struct sock *rsk;
 
 	if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
-		struct dst_entry *dst = sk->sk_rx_dst;
+		struct dst_entry *dst;
+
+		dst = rcu_dereference_protected(sk->sk_rx_dst,
+						lockdep_sock_is_held(sk));
 
 		sock_rps_save_rxhash(sk, skb);
 		sk_mark_napi_id(sk, skb);
@@ -1709,8 +1712,8 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 			if (sk->sk_rx_dst_ifindex != skb->skb_iif ||
 			    !INDIRECT_CALL_1(dst->ops->check, ipv4_dst_check,
 					     dst, 0)) {
+				RCU_INIT_POINTER(sk->sk_rx_dst, NULL);
 				dst_release(dst);
-				sk->sk_rx_dst = NULL;
 			}
 		}
 		tcp_rcv_established(sk, skb);
@@ -1786,7 +1789,7 @@ int tcp_v4_early_demux(struct sk_buff *skb)
 		skb->sk = sk;
 		skb->destructor = sock_edemux;
 		if (sk_fullsock(sk)) {
-			struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst);
+			struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst);
 
 			if (dst)
 				dst = dst_check(dst, 0);
@@ -1800,8 +1803,7 @@ int tcp_v4_early_demux(struct sk_buff *skb)
 
 bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb)
 {
-	u32 limit = READ_ONCE(sk->sk_rcvbuf) + READ_ONCE(sk->sk_sndbuf);
-	u32 tail_gso_size, tail_gso_segs;
+	u32 limit, tail_gso_size, tail_gso_segs;
 	struct skb_shared_info *shinfo;
 	const struct tcphdr *th;
 	struct tcphdr *thtail;
@@ -1909,7 +1911,7 @@ no_coalesce:
 	 * to reduce memory overhead, so add a little headroom here.
 	 * Few sockets backlog are possibly concurrently non empty.
 	 */
-	limit += 64*1024;
+	limit = READ_ONCE(sk->sk_rcvbuf) + READ_ONCE(sk->sk_sndbuf) + 64*1024;
 
 	if (unlikely(sk_add_backlog(sk, skb, limit))) {
 		bh_unlock_sock(sk);
@@ -1969,8 +1971,10 @@ int tcp_v4_rcv(struct sk_buff *skb)
 	const struct tcphdr *th;
 	bool refcounted;
 	struct sock *sk;
+	int drop_reason;
 	int ret;
 
+	drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
 	if (skb->pkt_type != PACKET_HOST)
 		goto discard_it;
 
@@ -1982,8 +1986,10 @@ int tcp_v4_rcv(struct sk_buff *skb)
 
 	th = (const struct tcphdr *)skb->data;
 
-	if (unlikely(th->doff < sizeof(struct tcphdr) / 4))
+	if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) {
+		drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL;
 		goto bad_packet;
+	}
 	if (!pskb_may_pull(skb, th->doff * 4))
 		goto discard_it;
 
@@ -2088,8 +2094,10 @@ process:
 
 	nf_reset_ct(skb);
 
-	if (tcp_filter(sk, skb))
+	if (tcp_filter(sk, skb)) {
+		drop_reason = SKB_DROP_REASON_TCP_FILTER;
 		goto discard_and_relse;
+	}
 	th = (const struct tcphdr *)skb->data;
 	iph = ip_hdr(skb);
 	tcp_v4_fill_cb(skb, iph, th);
@@ -2103,6 +2111,7 @@ process:
 
 	sk_incoming_cpu_update(sk);
 
+	sk_defer_free_flush(sk);
 	bh_lock_sock_nested(sk);
 	tcp_segs_in(tcp_sk(sk), skb);
 	ret = 0;
@@ -2121,6 +2130,7 @@ put_and_return:
 	return ret;
 
 no_tcp_socket:
+	drop_reason = SKB_DROP_REASON_NO_SOCKET;
 	if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
 		goto discard_it;
 
@@ -2128,6 +2138,7 @@ no_tcp_socket:
 
 	if (tcp_checksum_complete(skb)) {
 csum_error:
+		drop_reason = SKB_DROP_REASON_TCP_CSUM;
 		trace_tcp_bad_csum(skb);
 		__TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
 bad_packet:
@@ -2138,7 +2149,7 @@ bad_packet:
 
 discard_it:
 	/* Discard frame. */
-	kfree_skb(skb);
+	kfree_skb_reason(skb, drop_reason);
 	return 0;
 
 discard_and_relse:
@@ -2201,7 +2212,7 @@ void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
 	struct dst_entry *dst = skb_dst(skb);
 
 	if (dst && dst_hold_safe(dst)) {
-		sk->sk_rx_dst = dst;
+		rcu_assign_pointer(sk->sk_rx_dst, dst);
 		sk->sk_rx_dst_ifindex = skb->skb_iif;
 	}
 }
@@ -3073,6 +3084,7 @@ struct proto tcp_prot = {
 	.hash			= inet_hash,
 	.unhash			= inet_unhash,
 	.get_port		= inet_csk_get_port,
+	.put_port		= inet_put_port,
 #ifdef CONFIG_BPF_SYSCALL
 	.psock_update_sk_prot	= tcp_bpf_update_proto,
 #endif