From 9001cb1102cddba54f0e84e147dfbb0356067356 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Wed, 3 Aug 2022 11:41:53 +0200 Subject: [PATCH] assert: Do not use stderr in libc-internal assert Redirect internal assertion failures to __libc_assert_fail, based on based on __libc_message, which writes directly to STDERR_FILENO and calls abort. Also disable message translation and reword the error message slightly (adjusting stdlib/tst-bz20544 accordingly). As a result of these changes, malloc no longer needs its own redefinition of __assert_fail. __libc_assert_fail needs to be stubbed out during rtld dependency analysis because the rtld rebuilds turn __libc_assert_fail into __assert_fail, which is unconditionally provided by elf/dl-minimal.c. This change is not possible for the public assert macro and its __assert_fail function because POSIX requires that the diagnostic is written to stderr. Reviewed-by: Adhemerval Zanella --- assert/Makefile | 7 ++++++- assert/__libc_assert_fail.c | 33 +++++++++++++++++++++++++++++++++ assert/assert.c | 1 - elf/Makefile | 1 + include/assert.h | 12 +++++++++--- malloc/malloc.c | 16 ---------------- stdlib/tst-bz20544.c | 2 +- 7 files changed, 50 insertions(+), 22 deletions(-) create mode 100644 assert/__libc_assert_fail.c diff --git a/assert/Makefile b/assert/Makefile index f7cf8e9b77..c905845a43 100644 --- a/assert/Makefile +++ b/assert/Makefile @@ -24,7 +24,12 @@ include ../Makeconfig headers := assert.h -routines := assert assert-perr __assert +routines := \ + __assert \ + __libc_assert_fail \ + assert \ + assert-perr \ + # routines tests := test-assert test-assert-perr tst-assert-c++ tst-assert-g++ ifeq ($(have-cxx-thread_local),yes) diff --git a/assert/__libc_assert_fail.c b/assert/__libc_assert_fail.c new file mode 100644 index 0000000000..149d5feae1 --- /dev/null +++ b/assert/__libc_assert_fail.c @@ -0,0 +1,33 @@ +/* libc-internal assert that calls __libc_message. + Copyright (C) 2022 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 + . */ + +#include <_itoa.h> +#include +#include +#include + +void +__libc_assert_fail (const char *assertion, const char *file, unsigned int line, + const char *function) +{ + char linebuf[INT_BUFSIZE_BOUND (unsigned int)]; + array_end (linebuf)[-1] = '\0'; + char *linestr = _itoa_word (line, array_end (linebuf) - 1, 10, 0); + __libc_message ("Fatal glibc error: %s:%s (%s): assertion failed: %s\n", + file, linestr, function, assertion); +} diff --git a/assert/assert.c b/assert/assert.c index 133a183bc3..564ae28a2b 100644 --- a/assert/assert.c +++ b/assert/assert.c @@ -101,4 +101,3 @@ __assert_fail (const char *assertion, const char *file, unsigned int line, __assert_fail_base (_("%s%s%s:%u: %s%sAssertion `%s' failed.\n%n"), assertion, file, line, function); } -hidden_def(__assert_fail) diff --git a/elf/Makefile b/elf/Makefile index fd77d0c7c8..3386f0ce77 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -1283,6 +1283,7 @@ $(objpfx)dl-allobjs.os: $(all-rtld-routines:%=$(objpfx)%.os) rtld-stubbed-symbols = \ __GI___pthread_disable_asynccancel \ __GI___pthread_enable_asynccancel \ + __libc_assert_fail \ __pthread_disable_asynccancel \ __pthread_enable_asynccancel \ calloc \ diff --git a/include/assert.h b/include/assert.h index 61cc8aa22f..c812808f9b 100644 --- a/include/assert.h +++ b/include/assert.h @@ -20,8 +20,14 @@ extern void __assert_fail_base (const char *fmt, const char *assertion, const char *function) __THROW __attribute__ ((__noreturn__)) attribute_hidden; -# if IS_IN (libc) || (IS_IN (rtld) && !defined NO_RTLD_HIDDEN) -hidden_proto (__assert_fail) -hidden_proto (__assert_perror_fail) +rtld_hidden_proto (__assert_fail) +rtld_hidden_proto (__assert_perror_fail) +libc_hidden_proto (__assert_perror_fail) + + +# if IS_IN (libc) +/* Redirect to the internal version which does not use stderr. */ +extern _Noreturn __typeof (__assert_fail) __libc_assert_fail attribute_hidden; +# define __assert_fail __libc_assert_fail # endif #endif diff --git a/malloc/malloc.c b/malloc/malloc.c index b2017c8fa7..914052eb69 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -288,22 +288,6 @@ #define MALLOC_DEBUG 0 #endif -#if IS_IN (libc) -#ifndef NDEBUG -# define __assert_fail(assertion, file, line, function) \ - __malloc_assert(assertion, file, line, function) - -_Noreturn static void -__malloc_assert (const char *assertion, const char *file, unsigned int line, - const char *function) -{ - __libc_message ("Fatal glibc error: malloc assertion failure in %s: %s\n", - function, assertion); - __builtin_unreachable (); -} -#endif -#endif - #if USE_TCACHE /* We want 64 entries. This is an arbitrary limit, which tunables can reduce. */ # define TCACHE_MAX_BINS 64 diff --git a/stdlib/tst-bz20544.c b/stdlib/tst-bz20544.c index 411cd3f3ba..7cc236a1b1 100644 --- a/stdlib/tst-bz20544.c +++ b/stdlib/tst-bz20544.c @@ -78,7 +78,7 @@ test_bz20544_cxa_at_quick_exit (void *closure) static void test_one_fn (void (*test_fn) (void *)) { - const char expected_error[] = "Assertion `func != NULL' failed.\n"; + const char expected_error[] = "assertion failed: func != NULL\n"; struct support_capture_subprocess result; result = support_capture_subprocess (test_fn, NULL); support_capture_subprocess_check (&result, "bz20544", -SIGABRT,