3 files changed, 27 insertions, 25 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index f115ea68a4ef..6adb1abf05e0 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2246,7 +2246,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
                 /* Values greater than interface MTU won't take effect. However
                  * at the point when this call is done we typically don't yet
                  * know which interface is going to be used */
-                if (val < 8 || val > MAX_TCP_WINDOW) {
+                if (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW) {
                         err = -EINVAL;
                         break;
                 }
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 020766292bb0..cb8d305cb5b4 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -415,6 +415,9 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
                     !icsk->icsk_backoff)
                         break;
 
+                if (sock_owned_by_user(sk))
+                        break;
+
                 icsk->icsk_backoff--;
                 inet_csk(sk)->icsk_rto = __tcp_set_rto(tp) <<
                                          icsk->icsk_backoff;
@@ -429,11 +432,6 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
                 if (remaining) {
                         inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
                                                   remaining, TCP_RTO_MAX);
-                } else if (sock_owned_by_user(sk)) {
-                        /* RTO revert clocked out retransmission,
-                         * but socket is locked. Will defer. */
-                        inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
-                                                  HZ/20, TCP_RTO_MAX);
                 } else {
                         /* RTO revert clocked out retransmission.
                          * Will retransmit now */
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index de3bd8458588..7abecf73add9 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -237,11 +237,10 @@ void tcp_select_initial_window(int __space, __u32 mss,
                 /* when initializing use the value from init_rcv_wnd
                  * rather than the default from above
                  */
-                if (init_rcv_wnd &&
-                    (*rcv_wnd > init_rcv_wnd * mss))
-                        *rcv_wnd = init_rcv_wnd * mss;
-                else if (*rcv_wnd > init_cwnd * mss)
-                        *rcv_wnd = init_cwnd * mss;
+                if (init_rcv_wnd)
+                        *rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss);
+                else
+                        *rcv_wnd = min(*rcv_wnd, init_cwnd * mss);
         }
 
         /* Set the clamp no higher than max representable value */
@@ -392,27 +391,30 @@ struct tcp_out_options {
  */
 static u8 tcp_cookie_size_check(u8 desired)
 {
-        if (desired > 0) {
+        int cookie_size;
+
+        if (desired > 0)
                 /* previously specified */
                 return desired;
-        }
-        if (sysctl_tcp_cookie_size <= 0) {
+
+        cookie_size = ACCESS_ONCE(sysctl_tcp_cookie_size);
+        if (cookie_size <= 0)
                 /* no default specified */
                 return 0;
-        }
-        if (sysctl_tcp_cookie_size <= TCP_COOKIE_MIN) {
+
+        if (cookie_size <= TCP_COOKIE_MIN)
                 /* value too small, specify minimum */
                 return TCP_COOKIE_MIN;
-        }
-        if (sysctl_tcp_cookie_size >= TCP_COOKIE_MAX) {
+
+        if (cookie_size >= TCP_COOKIE_MAX)
                 /* value too large, specify maximum */
                 return TCP_COOKIE_MAX;
-        }
-        if (0x1 & sysctl_tcp_cookie_size) {
+
+        if (cookie_size & 1)
                 /* 8-bit multiple, illegal, fix it */
-                return (u8)(sysctl_tcp_cookie_size + 0x1);
-        }
-        return (u8)sysctl_tcp_cookie_size;
+                cookie_size++;
+
+        return (u8)cookie_size;
 }
 
 /* Write previously computed TCP options to the packet.
@@ -1519,6 +1521,7 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
         struct tcp_sock *tp = tcp_sk(sk);
         const struct inet_connection_sock *icsk = inet_csk(sk);
         u32 send_win, cong_win, limit, in_flight;
+        int win_divisor;
 
         if (TCP_SKB_CB(skb)->flags & TCPHDR_FIN)
                 goto send_now;
@@ -1550,13 +1553,14 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
         if ((skb != tcp_write_queue_tail(sk)) && (limit >= skb->len))
                 goto send_now;
 
-        if (sysctl_tcp_tso_win_divisor) {
+        win_divisor = ACCESS_ONCE(sysctl_tcp_tso_win_divisor);
+        if (win_divisor) {
                 u32 chunk = min(tp->snd_wnd, tp->snd_cwnd * tp->mss_cache);
 
                 /* If at least some fraction of a window is available,
                  * just use it.
                  */
-                chunk /= sysctl_tcp_tso_win_divisor;
+                chunk /= win_divisor;
                 if (limit >= chunk)
                         goto send_now;
         } else {