From: Florin Coras <fcoras@cisco.com>
Date: Fri, 23 Apr 2021 04:10:02 +0000 (-0700)
Subject: tcp: try to update sack list only if not empty
X-Git-Tag: v21.10-rc0~203
X-Git-Url: https://gerrit.fd.io/r/gitweb?a=commitdiff_plain;h=refs%2Fchanges%2F00%2F32100%2F3;p=vpp.git

tcp: try to update sack list only if not empty

Type: fix

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: Ieb5af96de5be33356dbab7bc4ab4696731fa8866
---

diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c
index 398bf1b76a7..5ec4099fa46 100644
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -1187,7 +1187,7 @@ tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
     }
 
   /* Update SACK list if need be */
-  if (tcp_opts_sack_permitted (&tc->rcv_opts))
+  if (tcp_opts_sack_permitted (&tc->rcv_opts) && vec_len (tc->snd_sacks))
     {
       /* Remove SACK blocks that have been delivered */
       tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);