3 files changed, 6 insertions, 3 deletions

diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index adf2068d12b5..9c802a6b04d3 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -377,7 +377,7 @@ enum
 #define RTAX_MAX (__RTAX_MAX - 1)
 
 #define RTAX_FEATURE_ECN        0x00000001
-#define RTAX_FEATURE_SACK       0x00000002
+#define RTAX_FEATURE_NO_SACK    0x00000002
 #define RTAX_FEATURE_TIMESTAMP  0x00000004
 #define RTAX_FEATURE_ALLFRAG    0x00000008
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c7625005486d..5fb25f977451 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3763,7 +3763,8 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx,
                                 break;
                         case TCPOPT_SACK_PERM:
                                 if (opsize == TCPOLEN_SACK_PERM && th->syn &&
-                                    !estab && sysctl_tcp_sack) {
+                                    !estab && sysctl_tcp_sack &&
+                                    !dst_feature(dst, RTAX_FEATURE_NO_SACK)) {
                                         opt_rx->sack_ok = 1;
                                         tcp_sack_reset(opt_rx);
                                 }
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 2e2eb74ac4cc..b35802af3c4c 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -464,6 +464,7 @@ static unsigned tcp_syn_options(struct sock *sk, struct sk_buff *skb,
                                 struct tcp_md5sig_key **md5) {
         struct tcp_sock *tp = tcp_sk(sk);
         unsigned size = 0;
+        struct dst_entry *dst = __sk_dst_get(sk);
 
 #ifdef CONFIG_TCP_MD5SIG
         *md5 = tp->af_specific->md5_lookup(sk, sk);
@@ -498,7 +499,8 @@ static unsigned tcp_syn_options(struct sock *sk, struct sk_buff *skb,
                 opts->options |= OPTION_WSCALE;
                 size += TCPOLEN_WSCALE_ALIGNED;
         }
-        if (likely(sysctl_tcp_sack)) {
+        if (likely(sysctl_tcp_sack &&
+                   !dst_feature(dst, RTAX_FEATURE_NO_SACK))) {
                 opts->options |= OPTION_SACK_ADVERTISE;
                 if (unlikely(!(OPTION_TS & opts->options)))
                         size += TCPOLEN_SACKPERM_ALIGNED;