mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-27 04:41:02 +08:00
1bdda52fe9
This patch moves the vDSO setup from libc to loader code, just after the vDSO link_map setup. For static case the initialization is moved to _dl_non_dynamic_init instead. Instead of using the mangled pointer, the vDSO data is set as attribute_relro (on _rtld_global_ro for shared or _dl_vdso_* for static). It is read-only even with partial relro. It fixes BZ#24967 now that the vDSO pointer is setup earlier than malloc interposition is called. Also, vDSO calls should not be a problem for static dlopen as indicated by BZ#20802. The vDSO pointer would be zero-initialized and the syscall will be issued instead. Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu, s390x-linux-gnu, sparc64-linux-gnu, and sparcv9-linux-gnu. I also run some tests on mips. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
99 lines
2.8 KiB
C
99 lines
2.8 KiB
C
/* Initialization code run first thing by the ELF startup code. Common version
|
|
Copyright (C) 1995-2020 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <ctype.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include <sysdep.h>
|
|
#include <fpu_control.h>
|
|
#include <sys/param.h>
|
|
#include <sys/types.h>
|
|
#include <libc-internal.h>
|
|
|
|
#include <ldsodefs.h>
|
|
|
|
/* Set nonzero if we have to be prepared for more than one libc being
|
|
used in the process. Safe assumption if initializer never runs. */
|
|
int __libc_multiple_libcs attribute_hidden = 1;
|
|
|
|
/* Remember the command line argument and enviroment contents for
|
|
later calls of initializers for dynamic libraries. */
|
|
int __libc_argc attribute_hidden;
|
|
char **__libc_argv attribute_hidden;
|
|
|
|
|
|
void
|
|
__libc_init_first (int argc, char **argv, char **envp)
|
|
{
|
|
#ifdef SHARED
|
|
/* For DSOs we do not need __libc_init_first but instead _init. */
|
|
}
|
|
|
|
void
|
|
attribute_hidden
|
|
_init (int argc, char **argv, char **envp)
|
|
{
|
|
#endif
|
|
|
|
__libc_multiple_libcs = &_dl_starting_up && !_dl_starting_up;
|
|
|
|
/* Make sure we don't initialize twice. */
|
|
if (!__libc_multiple_libcs)
|
|
{
|
|
/* Set the FPU control word to the proper default value if the
|
|
kernel would use a different value. */
|
|
if (__fpu_control != GLRO(dl_fpu_control))
|
|
__setfpucw (__fpu_control);
|
|
}
|
|
|
|
/* Save the command-line arguments. */
|
|
__libc_argc = argc;
|
|
__libc_argv = argv;
|
|
__environ = envp;
|
|
|
|
#ifndef SHARED
|
|
/* First the initialization which normally would be done by the
|
|
dynamic linker. */
|
|
_dl_non_dynamic_init ();
|
|
#endif
|
|
|
|
__init_misc (argc, argv, envp);
|
|
|
|
/* Initialize ctype data. */
|
|
__ctype_init ();
|
|
|
|
#if defined SHARED && !defined NO_CTORS_DTORS_SECTIONS
|
|
__libc_global_ctors ();
|
|
#endif
|
|
}
|
|
|
|
/* This function is defined here so that if this file ever gets into
|
|
ld.so we will get a link error. Having this file silently included
|
|
in ld.so causes disaster, because the _init definition above will
|
|
cause ld.so to gain an init function, which is not a cool thing. */
|
|
|
|
extern void _dl_start (void) __attribute__ ((noreturn));
|
|
|
|
void
|
|
_dl_start (void)
|
|
{
|
|
abort ();
|
|
}
|