commit 128183a5ffff59c96d442144ad10661f6fcd9710
author lifr <lifr@google.com> Wed Jan 08 18:04:50 2020 +0800
committer Frank Li <lifr@google.com> Mon Feb 17 13:43:32 2020 +0000
tree 23dd098745da2c6afba98ba4fdf91a2f5c575d06
parent 731dc404a45c92211c926f3e4dff1fdd06603342

Fix retry time value in dnsQueryEvent when perform DNS query over TCP

DNS queries over TCP can only be made once per server.
The retry time value of dnsQueryEvent on TCP should always be "0".
(Currently, it will populate the wrong value from the variable
"retryTimes".)

Bug: 147343838
Test: atest
Change-Id: I67b9602fcf9882e8035765e1598c16cf36bfb5e4

res_send.cpp

diff --git a/res_send.cpp b/res_send.cpp
index 66548bd..5b5fe10 100644
--- a/res_send.cpp
+++ b/res_send.cpp
@@ -506,6 +506,7 @@
             const bool shouldRecordStats = (attempt == 0);
             int resplen;
             Stopwatch queryStopwatch;
+            int retry_count_for_event = 0;
             if (useTcp) {
                 // TCP; at most one attempt per server.
                 attempt = retryTimes;
@@ -524,6 +525,7 @@
                 resplen = send_dg(statp, &params, buf, buflen, ans, anssiz, &terrno, ns, &useTcp,
                                   &gotsomewhere, &now, rcode, &delay);
                 fallbackTCP = useTcp ? true : false;
+                retry_count_for_event = attempt;
                 LOG(INFO) << __func__ << ": used send_dg " << resplen;
             }
 
@@ -532,7 +534,7 @@
             dnsQueryEvent->set_latency_micros(saturate_cast<int32_t>(queryStopwatch.timeTakenUs()));
             dnsQueryEvent->set_dns_server_index(ns);
             dnsQueryEvent->set_ip_version(ipFamilyToIPVersion(nsap->sa_family));
-            dnsQueryEvent->set_retry_times(attempt);
+            dnsQueryEvent->set_retry_times(retry_count_for_event);
             dnsQueryEvent->set_rcode(static_cast<NsRcode>(*rcode));
             dnsQueryEvent->set_protocol(query_proto);
             dnsQueryEvent->set_type(getQueryType(buf, buflen));