From fd78cfa72ea2bab30fdb4e1e0672b34471426c05 Mon Sep 17 00:00:00 2001 From: Vitaly Buka Date: Sat, 18 Feb 2023 12:53:41 -0800 Subject: [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] Content-type: text/plain; charset=UTF-8 Post review removal of "goto restart" from https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html introduced a bug when some atexit handers skipped. Signed-off-by: Vitaly Buka Reviewed-by: Adhemerval Zanella --- stdlib/Makefile | 1 + stdlib/exit.c | 7 +++- stdlib/test-atexit-recursive.c | 75 ++++++++++++++++++++++++++++++++++ 3 files changed, 81 insertions(+), 2 deletions(-) create mode 100644 stdlib/test-atexit-recursive.c diff --git a/stdlib/Makefile b/stdlib/Makefile index ff5096ad1b..cd32f53b56 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -171,6 +171,7 @@ tests := \ test-a64l \ test-at_quick_exit-race \ test-atexit-race \ + test-atexit-recursive \ test-bz22786 \ test-canon \ test-canon2 \ diff --git a/stdlib/exit.c b/stdlib/exit.c index 6b1eed6445..1cd0bdfe94 100644 --- a/stdlib/exit.c +++ b/stdlib/exit.c @@ -51,7 +51,10 @@ __run_exit_handlers (int status, struct exit_function_list **listp, exit (). */ while (true) { - struct exit_function_list *cur = *listp; + struct exit_function_list *cur; + + restart: + cur = *listp; if (cur == NULL) { @@ -113,7 +116,7 @@ __run_exit_handlers (int status, struct exit_function_list **listp, if (__glibc_unlikely (new_exitfn_called != __new_exitfn_called)) /* The last exit function, or another thread, has registered more exit functions. Start the loop over. */ - continue; + goto restart; } *listp = cur->next; diff --git a/stdlib/test-atexit-recursive.c b/stdlib/test-atexit-recursive.c new file mode 100644 index 0000000000..0596b9763b --- /dev/null +++ b/stdlib/test-atexit-recursive.c @@ -0,0 +1,75 @@ +/* Support file for atexit/exit, etc. race tests (BZ #27749). + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +/* Check that atexit handler registed from another handler still called. */ + +#include +#include +#include +#include +#include +#include + +static void +atexit_cb (void) +{ +} + +static void +atexit_last (void) +{ + _exit (1); +} + +static void +atexit_recursive (void) +{ + atexit (&atexit_cb); + atexit (&atexit_last); +} + +_Noreturn static void +test_and_exit (int count) +{ + for (int i = 0; i < count; ++i) + atexit (&atexit_cb); + atexit (&atexit_recursive); + exit (0); +} + +static int +do_test (void) +{ + for (int i = 0; i < 100; ++i) + if (xfork () == 0) + test_and_exit (i); + + for (int i = 0; i < 100; ++i) + { + int status; + xwaitpid (0, &status, 0); + if (!WIFEXITED (status)) + FAIL_EXIT1 ("Failed iterations %d", i); + TEST_COMPARE (WEXITSTATUS (status), 1); + } + + return 0; +} + +#define TEST_FUNCTION do_test +#include -- 2.39.2