From 49d173f4e4c05bbc9e6f256f8914979dad85e9d3 Mon Sep 17 00:00:00 2001
From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Sun, 6 Sep 2020 12:15:10 +0100
Subject: [PATCH 38/42] GnuTLS: clear errno before any data i/o op, so error
 logging does not see stale values

(cherry picked from commit d52a8ce8499fbb88f4670623df9f52d3e790292b)
---
 src/tls-gnu.c | 3 +++

diff --git src/tls-gnu.c src/tls-gnu.c
index dafe1be0c..6ee603595 100644
--- src/tls-gnu.c
+++ src/tls-gnu.c
@@ -3162,6 +3162,7 @@ DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(session=%p, buffer=%p, buf
 sigalrm_seen = FALSE;
 if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
 
+errno = 0;
 do
   inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
     MIN(ssl_xfer_buffer_size, lim));
@@ -3322,6 +3323,7 @@ DEBUG(D_tls)
   debug_printf("Calling gnutls_record_recv(session=%p, buffer=%p, len=" SIZE_T_FMT ")\n",
       state->session, buff, len);
 
+errno = 0;
 do
   inbytes = gnutls_record_recv(state->session, buff, len);
 while (inbytes == GNUTLS_E_AGAIN);
@@ -3385,6 +3387,7 @@ while (left > 0)
   DEBUG(D_tls) debug_printf("gnutls_record_send(session=%p, buffer=%p, left=" SIZE_T_FMT ")\n",
       state->session, buff, left);
 
+  errno = 0;
   do
     outbytes = gnutls_record_send(state->session, buff, left);
   while (outbytes == GNUTLS_E_AGAIN);
-- 
2.29.2