glibc/sysdeps/gnu/unwind-resume.c
Tulio Magno Quites Machado Filho 81b49e9692 Increase robustness of internal dlopen() by using RTLD_NOW [BZ #22766]
Prevent random runtime crashes due to missing symbols caused by mixed
libnss_* versions.

	[BZ #22766]
	* include/dlfcn.h [__libc_dl_open]: Replace RTLD_LAZY with RTLD_NOW.
	* sysdeps/gnu/unwind-resume.c (__lib_gcc_s_init): Replace
	__libc_dlopen_mode() using RTLD_NOW with __libc_dlopen.
	* sysdeps/nptl/unwind-forcedunwind.c: Likewise.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-04-26 10:41:43 -03:00

84 lines
2.4 KiB
C

/* Copyright (C) 2003-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>.
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; see the file COPYING.LIB. If
not, see <http://www.gnu.org/licenses/>. */
#include <dlfcn.h>
#include <stdio.h>
#include <unwind.h>
#include <gnu/lib-names.h>
#include <sysdep.h>
#include <unwind-resume.h>
void (*__libgcc_s_resume) (struct _Unwind_Exception *exc)
attribute_hidden __attribute__ ((noreturn));
static _Unwind_Reason_Code (*libgcc_s_personality) PERSONALITY_PROTO;
void attribute_hidden __attribute__ ((cold))
__libgcc_s_init (void)
{
void *resume, *personality;
void *handle;
/* See include/dlfcn.h. Use of __libc_dlopen requires RTLD_NOW. */
handle = __libc_dlopen (LIBGCC_S_SO);
if (handle == NULL
|| (resume = __libc_dlsym (handle, "_Unwind_Resume")) == NULL
|| (personality = __libc_dlsym (handle, "__gcc_personality_v0")) == NULL)
__libc_fatal (LIBGCC_S_SO
" must be installed for unwinding to work\n");
#ifdef PTR_MANGLE
PTR_MANGLE (resume);
#endif
__libgcc_s_resume = resume;
#ifdef PTR_MANGLE
PTR_MANGLE (personality);
#endif
libgcc_s_personality = personality;
}
#if !HAVE_ARCH_UNWIND_RESUME
void
_Unwind_Resume (struct _Unwind_Exception *exc)
{
if (__glibc_unlikely (__libgcc_s_resume == NULL))
__libgcc_s_init ();
__typeof (__libgcc_s_resume) resume = __libgcc_s_resume;
#ifdef PTR_DEMANGLE
PTR_DEMANGLE (resume);
#endif
(*resume) (exc);
}
#endif
_Unwind_Reason_Code
__gcc_personality_v0 PERSONALITY_PROTO
{
if (__glibc_unlikely (libgcc_s_personality == NULL))
__libgcc_s_init ();
__typeof (libgcc_s_personality) personality = libgcc_s_personality;
#ifdef PTR_DEMANGLE
PTR_DEMANGLE (personality);
#endif
return (*personality) PERSONALITY_ARGS;
}