From 88f5f3915b557eef68864df4c80eee8750208108 Mon Sep 17 00:00:00 2001
From: Evan Hunt <each@isc.org>
Date: Thu, 5 Nov 2020 14:15:14 -0800
Subject: [PATCH] dig: prevent query from being detached if udpconnect fails on
 first attempt

FreeBSD sometimes returns spurious errors in UDP connect() attempts,
so we try a few times before giving up. However, each failed attempt
triggers a call to udp_ready() in dighost.c, and that was causing
the query object to be detached prematurely.
---
 bin/dig/dighost.c | 10 ++++++----
 bin/dig/dighost.h |  1 +
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/bin/dig/dighost.c b/bin/dig/dighost.c
index 081518cb17..d7b04c02ea 100644
--- a/bin/dig/dighost.c
+++ b/bin/dig/dighost.c
@@ -2897,7 +2897,9 @@ udp_ready(isc_nmhandle_t *handle, isc_result_t eresult, void *arg) {
 			debug("udp setup failed: %s",
 			      isc_result_totext(eresult));
 		}
-		query_detach(&query);
+		if (query->tries == 0) {
+			query_detach(&query);
+		}
 		return;
 	}
 
@@ -2933,7 +2935,6 @@ static void
 start_udp(dig_query_t *query) {
 	isc_result_t result;
 	dig_query_t *next = NULL;
-	int i = 0;
 
 	REQUIRE(DIG_VALID_QUERY(query));
 
@@ -2985,6 +2986,7 @@ start_udp(dig_query_t *query) {
 		}
 	}
 
+	query->tries = 3;
 	do {
 		int local_timeout = timeout * 1000;
 		if (local_timeout == 0) {
@@ -2996,11 +2998,11 @@ start_udp(dig_query_t *query) {
 		 * in a spurious transient EADDRINUSE. Try a few more times
 		 * before giving up.
 		 */
-		debug("isc_nm_udpconnect(): try %d", i + 1);
+		debug("isc_nm_udpconnect(): %d tries left", --query->tries);
 		result = isc_nm_udpconnect(netmgr, (isc_nmiface_t *)&localaddr,
 					   (isc_nmiface_t *)&query->sockaddr,
 					   udp_ready, query, local_timeout, 0);
-	} while (result != ISC_R_SUCCESS && i++ < 2);
+	} while (result != ISC_R_SUCCESS && query->tries > 0);
 	check_result(result, "isc_nm_udpconnect");
 }
 
diff --git a/bin/dig/dighost.h b/bin/dig/dighost.h
index 6a30b5ef85..81cc2750a1 100644
--- a/bin/dig/dighost.h
+++ b/bin/dig/dighost.h
@@ -199,6 +199,7 @@ struct dig_query {
 	isc_time_t time_recv;
 	uint64_t byte_count;
 	isc_timer_t *timer;
+	uint8_t tries;
 };
 
 struct dig_server {