adjust timeout to allow for ECN negotiation failures

(cherry picked from commit dadb924be766eb8bfb922eacc8015c33c08d206b)

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index dccdc6be961039337a126ba96f36c8d8549dc40b..cbf6b5ca28bd6122fe15b738c85161fd16d32114 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -1883,6 +1883,15 @@ fctx_query(fetchctx_t *fctx, dns_adbaddrinfo_t *addrinfo,
 
        srtt = addrinfo->srtt;
 
+       /*
+        * Allow an additional second for the kernel to resend the SYN (or
+        * SYN without ECN in the case of stupid firewalls blocking ECN
+        * negotiation) over the current RTT estimate.
+        */
+       if ((options & DNS_FETCHOPT_TCP) != 0) {
+               srtt += 1000000;
+       }
+
        /*
         * A forwarder needs to make multiple queries. Give it at least
         * a second to do these in.