From 3231ac6008bdcfe605b97bf09d79b3e58a2e58a3 Mon Sep 17 00:00:00 2001 From: Kasumi Hanazuki Date: Sat, 31 Aug 2024 07:31:42 +0000 Subject: [PATCH] [ruby/resolv] test_dns: Fix FD leak The listening TCP socket is closed by `with_udp_and_tcp` helper, but the connected socket is leaking. ``` Leaked file descriptor: TestResolvDNS#test_multiple_servers_with_timeout_and_truncated_tcp_fallback: 12 : # COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME ruby 3248055 chkbuild 12u IPv4 112546322 0t0 TCP localhost:50888->localhost:40112 (CLOSE_WAIT) ``` For the purpose of the test case to simulate a timeout over TCP transport, we have to delay closing this socket until the end the test case. Fixup: https://github.com/ruby/resolv/pull/50 https://github.com/ruby/resolv/commit/236c38bdb1 --- test/resolv/test_dns.rb | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/test/resolv/test_dns.rb b/test/resolv/test_dns.rb index f9224fbebe..03d997d5b9 100644 --- a/test/resolv/test_dns.rb +++ b/test/resolv/test_dns.rb @@ -758,7 +758,10 @@ class TestResolvDNS < Test::Unit::TestCase u1.send(msg[0...512], 0, client_address, client_port) end - tcp_server1_thread = Thread.new { t1.accept; t1.close } + tcp_server1_thread = Thread.new do + # Keep this socket open so that the client experiences a timeout + t1.accept + end tcp_server2_thread = Thread.new do ct = t2.accept @@ -800,7 +803,7 @@ class TestResolvDNS < Test::Unit::TestCase ct.send(msg, 0) ct.close end - result, = assert_join_threads([client_thread, udp_server1_thread, tcp_server1_thread, tcp_server2_thread]) + result, _, tcp_server1_socket, = assert_join_threads([client_thread, udp_server1_thread, tcp_server1_thread, tcp_server2_thread]) assert_instance_of(Array, result) assert_equal(50, result.length) result.each_with_index do |rr, i| @@ -809,6 +812,8 @@ class TestResolvDNS < Test::Unit::TestCase assert_equal("192.0.2.#{i}", rr.address.to_s) assert_equal(3600, rr.ttl) end + ensure + tcp_server1_socket&.close end end end