From 9fb237a1c861f3b6a014f7add3f564452ea23e61 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Fri, 16 Aug 2024 14:38:33 +0100 Subject: [PATCH] nptl: Fix extraneous testing run by tst-rseq-nptl in the test driver Fix an issue with commit 8f4632deb354 ("Linux: rseq registration tests") and prevent testing from being run in the process of the test driver itself rather than just the test child where one has been forked. The problem here is the unguarded use of a destructor to call a part of the testing. The destructor function, 'do_rseq_destructor_test' is called implicitly at program completion, however because it is associated with the executable itself rather than an individual process, it is called both in the test child *and* in the test driver itself. Prevent this from happening by providing a guard variable that only enables test invocation from 'do_rseq_destructor_test' in the process that has first run 'do_test'. Consequently extra testing is invoked from 'do_rseq_destructor_test' only once and in the correct process, regardless of the use or the lack of of the '--direct' option. Where called in the controlling test driver process that has neved called 'do_test' the destructor function silently returns right away without taking any further actions, letting the test driver fail gracefully where applicable. This arrangement prevents 'tst-rseq-nptl' from ever causing testing to hang forever and never complete, such as currently happening with the 'mips-linux-gnu' (o32 ABI) target. Reviewed-by: Adhemerval Zanella --- sysdeps/unix/sysv/linux/tst-rseq-nptl.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/sysdeps/unix/sysv/linux/tst-rseq-nptl.c b/sysdeps/unix/sysv/linux/tst-rseq-nptl.c index b9f498473d..2a246c4593 100644 --- a/sysdeps/unix/sysv/linux/tst-rseq-nptl.c +++ b/sysdeps/unix/sysv/linux/tst-rseq-nptl.c @@ -28,6 +28,11 @@ #include #include +/* Set this in 'do_test' only so as to invoke the destructor test in + the test process only and not 'support_test_main' parent. Otherwise + the test harness may hang in the destructor if something goes wrong. */ +static int run_destructor_test; + #ifdef RSEQ_SIG # include # include @@ -236,6 +241,9 @@ do_rseq_test (void) static void __attribute__ ((destructor)) do_rseq_destructor_test (void) { + if (!run_destructor_test) + return; + /* Cannot use deferred failure reporting after main returns. */ if (do_rseq_test ()) FAIL_EXIT1 ("rseq not registered within destructor"); @@ -254,6 +262,7 @@ do_rseq_test (void) static int do_test (void) { + run_destructor_test = 1; return do_rseq_test (); } -- 2.43.5