4.4-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ Upstream commit 532182cd610782db8c18230c2747626562032205 ]
Now ss can report sk_drops, we can instruct TCP to increment this per socket counter when it drops an incoming frame, to refine monitoring and debugging.
Following patch takes care of listeners drops.
Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Mao Wenan maowenan@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/net/sock.h | 7 +++++++ net/ipv4/tcp_input.c | 33 ++++++++++++++++++++------------- net/ipv4/tcp_ipv4.c | 1 + net/ipv6/tcp_ipv6.c | 1 + 4 files changed, 29 insertions(+), 13 deletions(-)
--- a/include/net/sock.h +++ b/include/net/sock.h @@ -2139,6 +2139,13 @@ sock_skb_set_dropcount(const struct sock SOCK_SKB_CB(skb)->dropcount = atomic_read(&sk->sk_drops); }
+static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) +{ + int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); + + atomic_add(segs, &sk->sk_drops); +} + void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb); void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4296,6 +4296,12 @@ static bool tcp_try_coalesce(struct sock return true; }
+static void tcp_drop(struct sock *sk, struct sk_buff *skb) +{ + sk_drops_add(sk, skb); + __kfree_skb(skb); +} + /* This one checks to see if we can put data from the * out_of_order queue into the receive_queue. */ @@ -4320,7 +4326,7 @@ static void tcp_ofo_queue(struct sock *s __skb_unlink(skb, &tp->out_of_order_queue); if (!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) { SOCK_DEBUG(sk, "ofo packet was already received\n"); - __kfree_skb(skb); + tcp_drop(sk, skb); continue; } SOCK_DEBUG(sk, "ofo requeuing : rcv_next %X seq %X - %X\n", @@ -4372,7 +4378,7 @@ static void tcp_data_queue_ofo(struct so
if (unlikely(tcp_try_rmem_schedule(sk, skb, skb->truesize))) { NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFODROP); - __kfree_skb(skb); + tcp_drop(sk, skb); return; }
@@ -4436,7 +4442,7 @@ static void tcp_data_queue_ofo(struct so if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) { /* All the bits are present. Drop. */ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFOMERGE); - __kfree_skb(skb); + tcp_drop(sk, skb); skb = NULL; tcp_dsack_set(sk, seq, end_seq); goto add_sack; @@ -4475,7 +4481,7 @@ static void tcp_data_queue_ofo(struct so tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq, TCP_SKB_CB(skb1)->end_seq); NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFOMERGE); - __kfree_skb(skb1); + tcp_drop(sk, skb1); }
add_sack: @@ -4558,12 +4564,13 @@ err: static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); - int eaten = -1; bool fragstolen = false; + int eaten = -1;
- if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) - goto drop; - + if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) { + __kfree_skb(skb); + return; + } skb_dst_drop(skb); __skb_pull(skb, tcp_hdr(skb)->doff * 4);
@@ -4645,7 +4652,7 @@ out_of_window: tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); inet_csk_schedule_ack(sk); drop: - __kfree_skb(skb); + tcp_drop(sk, skb); return; }
@@ -5236,7 +5243,7 @@ syn_challenge: return true;
discard: - __kfree_skb(skb); + tcp_drop(sk, skb); return false; }
@@ -5454,7 +5461,7 @@ csum_error: TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);
discard: - __kfree_skb(skb); + tcp_drop(sk, skb); } EXPORT_SYMBOL(tcp_rcv_established);
@@ -5684,7 +5691,7 @@ static int tcp_rcv_synsent_state_process TCP_DELACK_MAX, TCP_RTO_MAX);
discard: - __kfree_skb(skb); + tcp_drop(sk, skb); return 0; } else { tcp_send_ack(sk); @@ -6041,7 +6048,7 @@ int tcp_rcv_state_process(struct sock *s
if (!queued) { discard: - __kfree_skb(skb); + tcp_drop(sk, skb); } return 0; } --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1716,6 +1716,7 @@ discard_it: return 0;
discard_and_relse: + sk_drops_add(sk, skb); sock_put(sk); goto discard_it;
--- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1505,6 +1505,7 @@ discard_it: return 0;
discard_and_relse: + sk_drops_add(sk, skb); sock_put(sk); goto discard_it;