From b8b53b338f6da91e86d115a39da860cefac736ad Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Thu, 15 Oct 2020 12:33:13 +0200 Subject: [PATCH] resolv: Serialize processing in resolv/tst-resolv-txnid-collision When switching name servers, response processing by two server threads clobbers the global test state. (There is still some risk that this test is negatively impact by packet drops and packet reordering, but this applies to many of the resolver tests and is difficult to avoid.) Fixes commit f1f00c072138af90ae6da180f260111f09afe7a3 ("resolv: Handle transaction ID collisions in parallel queries (bug 26600)"). --- resolv/tst-resolv-txnid-collision.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/resolv/tst-resolv-txnid-collision.c b/resolv/tst-resolv-txnid-collision.c index 611d37362f..189b76f126 100644 --- a/resolv/tst-resolv-txnid-collision.c +++ b/resolv/tst-resolv-txnid-collision.c @@ -309,6 +309,11 @@ do_test (void) ((struct resolv_redirect_config) { .response_callback = response, + + /* The response callback use global state (the previous_* + variables), and query processing must therefore be + serialized. */ + .single_thread_udp = true, }); for (int rcode = 0; rcode <= 5; ++rcode)