1 files changed, 23 insertions, 18 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c43119726a62..2c1f59386a7b 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -126,7 +126,8 @@ int sysctl_tcp_invalid_ratelimit __read_mostly = HZ/2;
 #define REXMIT_LOST     1 /* retransmit packets marked lost */
 #define REXMIT_NEW      2 /* FRTO-style transmit of unsent/new packets */
 
-static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb)
+static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb,
+                             unsigned int len)
 {
         static bool __once __read_mostly;
 
@@ -137,8 +138,9 @@ static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb)
 
                 rcu_read_lock();
                 dev = dev_get_by_index_rcu(sock_net(sk), skb->skb_iif);
-                pr_warn("%s: Driver has suspect GRO implementation, TCP performance may be compromised.\n",
-                        dev ? dev->name : "Unknown driver");
+                if (!dev || len >= dev->mtu)
+                        pr_warn("%s: Driver has suspect GRO implementation, TCP performance may be compromised.\n",
+                                dev ? dev->name : "Unknown driver");
                 rcu_read_unlock();
         }
 }
@@ -161,8 +163,10 @@ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb)
         if (len >= icsk->icsk_ack.rcv_mss) {
                 icsk->icsk_ack.rcv_mss = min_t(unsigned int, len,
                                                tcp_sk(sk)->advmss);
-                if (unlikely(icsk->icsk_ack.rcv_mss != len))
-                        tcp_gro_dev_warn(sk, skb);
+                /* Account for possibly-removed options */
+                if (unlikely(len > icsk->icsk_ack.rcv_mss +
+                                   MAX_TCP_OPTION_SPACE))
+                        tcp_gro_dev_warn(sk, skb, len);
         } else {
                 /* Otherwise, we make more careful check taking into account,
                  * that SACKs block is variable.
@@ -874,22 +878,11 @@ static void tcp_update_reordering(struct sock *sk, const int metric,
                                   const int ts)
 {
         struct tcp_sock *tp = tcp_sk(sk);
-        if (metric > tp->reordering) {
-                int mib_idx;
+        int mib_idx;
 
+        if (metric > tp->reordering) {
                 tp->reordering = min(sysctl_tcp_max_reordering, metric);
 
-                /* This exciting event is worth to be remembered. 8) */
-                if (ts)
-                        mib_idx = LINUX_MIB_TCPTSREORDER;
-                else if (tcp_is_reno(tp))
-                        mib_idx = LINUX_MIB_TCPRENOREORDER;
-                else if (tcp_is_fack(tp))
-                        mib_idx = LINUX_MIB_TCPFACKREORDER;
-                else
-                        mib_idx = LINUX_MIB_TCPSACKREORDER;
-
-                NET_INC_STATS(sock_net(sk), mib_idx);
 #if FASTRETRANS_DEBUG > 1
                 pr_debug("Disorder%d %d %u f%u s%u rr%d\n",
                          tp->rx_opt.sack_ok, inet_csk(sk)->icsk_ca_state,
@@ -902,6 +895,18 @@ static void tcp_update_reordering(struct sock *sk, const int metric,
         }
 
         tp->rack.reord = 1;
+
+        /* This exciting event is worth to be remembered. 8) */
+        if (ts)
+                mib_idx = LINUX_MIB_TCPTSREORDER;
+        else if (tcp_is_reno(tp))
+                mib_idx = LINUX_MIB_TCPRENOREORDER;
+        else if (tcp_is_fack(tp))
+                mib_idx = LINUX_MIB_TCPFACKREORDER;
+        else
+                mib_idx = LINUX_MIB_TCPSACKREORDER;
+
+        NET_INC_STATS(sock_net(sk), mib_idx);
 }
 
 /* This must be called before lost_out is incremented */