diff options
| -rw-r--r-- | ChangeLog | 8 | ||||
| -rw-r--r-- | stdlib/Makefile | 2 | ||||
| -rw-r--r-- | stdlib/cxa_atexit.c | 4 | ||||
| -rw-r--r-- | stdlib/on_exit.c | 5 | ||||
| -rw-r--r-- | stdlib/tst-bz20544.c | 115 |
5 files changed, 133 insertions, 1 deletions
@@ -1,3 +1,11 @@ +2018-12-01 Paul Pluzhnikov <ppluzhnikov@google.com> + + [BZ #20544] + * stdlib/cxa_atexit.c (__internal_atexit): assert func != NULL. + * stdlib/on_exit.c (__on_exit): Likewise. + * stdlib/Makefile (tests): Add tst-bz20544. + * stdlib/tst-bz20544.c: New test. + 2018-11-30 Rafael Ávila de Espíndola <rafael@espindo.la> [BZ #19767] diff --git a/stdlib/Makefile b/stdlib/Makefile index 98dbddc43c..8bce89fffe 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -87,7 +87,7 @@ tests := tst-strtol tst-strtod testmb testrand testsort testdiv \ tst-makecontext-align test-bz22786 tst-strtod-nan-sign \ tst-swapcontext1 tst-setcontext4 tst-setcontext5 \ tst-setcontext6 tst-setcontext7 tst-setcontext8 \ - tst-setcontext9 + tst-setcontext9 tst-bz20544 tests-internal := tst-strtod1i tst-strtod3 tst-strtod4 tst-strtod5i \ tst-tls-atexit tst-tls-atexit-nodelete diff --git a/stdlib/cxa_atexit.c b/stdlib/cxa_atexit.c index 6d65f7e615..37b22d5801 100644 --- a/stdlib/cxa_atexit.c +++ b/stdlib/cxa_atexit.c @@ -36,6 +36,10 @@ __internal_atexit (void (*func) (void *), void *arg, void *d, { struct exit_function *new; + /* As a QoI issue we detect NULL early with an assertion instead + of a SIGSEGV at program exit when the handler is run (bug 20544). */ + assert (func != NULL); + __libc_lock_lock (__exit_funcs_lock); new = __new_exitfn (listp); diff --git a/stdlib/on_exit.c b/stdlib/on_exit.c index 5241e0d86f..1dff7ff631 100644 --- a/stdlib/on_exit.c +++ b/stdlib/on_exit.c @@ -15,6 +15,7 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ +#include <assert.h> #include <stdlib.h> #include "exit.h" #include <sysdep.h> @@ -25,6 +26,10 @@ __on_exit (void (*func) (int status, void *arg), void *arg) { struct exit_function *new; + /* As a QoI issue we detect NULL early with an assertion instead + of a SIGSEGV at program exit when the handler is run (bug 20544). */ + assert (func != NULL); + __libc_lock_lock (__exit_funcs_lock); new = __new_exitfn (&__exit_funcs); diff --git a/stdlib/tst-bz20544.c b/stdlib/tst-bz20544.c new file mode 100644 index 0000000000..33b87cc77e --- /dev/null +++ b/stdlib/tst-bz20544.c @@ -0,0 +1,115 @@ +/* Verify atexit, on_exit, etc. abort on NULL function pointer. + Copyright (C) 2018 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 + <http://www.gnu.org/licenses/>. */ + + +#include <assert.h> +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <support/capture_subprocess.h> +#include <support/check.h> +#include <support/support.h> +#include <support/test-driver.h> + +extern int __cxa_atexit (void (*func) (void *), void *arg, void *d); +extern int __cxa_at_quick_exit (void (*func) (void *), void *arg, void *d); + +/* GCC "knows" that atexit and on_exit should not be called with NULL + function pointer, and emits diagnostics if we try to do so. + Presumably it could emit a trap and drop the call altogether. + + The aliases below are intended to bypass this. */ + +extern int atexit_alias (void (*) (void)) __asm__ ("atexit"); +extern int at_quick_exit_alias (void (*) (void)) __asm__ ("at_quick_exit"); +extern int on_exit_alias (void (*) (void), void *) __asm__ ("on_exit"); + + +static void +test_bz20544_atexit (void *closure) +{ + atexit_alias (NULL); /* Should assert. */ + exit (EXIT_FAILURE); +} + +static void +test_bz20544_at_quick_exit (void *closure) +{ + at_quick_exit_alias (NULL); /* Should assert. */ + exit (EXIT_FAILURE); +} + +static void +test_bz20544_on_exit (void *closure) +{ + on_exit_alias (NULL, NULL); /* Should assert. */ + exit (EXIT_FAILURE); +} + +static void +test_bz20544_cxa_atexit (void *closure) +{ + __cxa_atexit (NULL, NULL, NULL); /* Should assert. */ + exit (EXIT_FAILURE); +} + +static void +test_bz20544_cxa_at_quick_exit (void *closure) +{ + __cxa_at_quick_exit (NULL, NULL, NULL); /* Should assert. */ + exit (EXIT_FAILURE); +} + +static void +test_one_fn (void (*test_fn) (void *)) +{ + const char expected_error[] = "Assertion `func != NULL' failed.\n"; + struct support_capture_subprocess result; + result = support_capture_subprocess (test_fn, NULL); + support_capture_subprocess_check (&result, "bz20544", -SIGABRT, + sc_allow_stderr); + + if (strstr (result.err.buffer, expected_error) == NULL) + { + support_record_failure (); + printf ("Did not find expected string in error output:\n" + " expected: >>>%s<<<\n" + " actual: >>>%s<<<\n", + expected_error, result.err.buffer); + } + + support_capture_subprocess_free (&result); +} + +static int +do_test (void) +{ +#if defined (NDEBUG) + FAIL_UNSUPPORTED ("Assertions disabled (NDEBUG). " + "Can't verify that assertions fire."); +#endif + test_one_fn (test_bz20544_atexit); + test_one_fn (test_bz20544_at_quick_exit); + test_one_fn (test_bz20544_on_exit); + test_one_fn (test_bz20544_cxa_atexit); + test_one_fn (test_bz20544_cxa_at_quick_exit); + + return 0; +} + +#include <support/test-driver.c> |