glibc/elf/dl-reloc-static-pie.c
Adhemerval Zanella f6a54a3042 elf: Fix elf_get_dynamic_info() for bootstrap
THe d6d89608ac broke powerpc for --enable-bind-now because it turned
out that different than patch assumption rtld elf_get_dynamic_info()
does require to handle RTLD_BOOTSTRAP to avoid DT_FLAGS and
DT_RUNPATH (more specially the GLRO usage which is not reallocate
yet).

This patch fixes by passing two arguments to elf_get_dynamic_info()
to inform that by rtld (bootstrap) or static pie initialization
(static_pie_bootstrap).  I think using explicit argument is way more
clear and burried C preprocessor, and compiler should remove the
dead code.

I checked on x86_64 and i686 with default options, --enable-bind-now,
and --enable-bind-now and --enable--static-pie.  I also check on
aarch64, armhf, powerpc64, and powerpc with default and
--enable-bind-now.

(cherry picked from commit 5118dcac68)

Resolved conflicts:
	elf/rtld.c - Manual merge.
2022-04-08 14:18:11 -04:00

82 lines
2.7 KiB
C

/* Support for relocating static PIE.
Copyright (C) 2017-2021 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/>. */
#if ENABLE_STATIC_PIE
/* Mark symbols hidden in static PIE for early self relocation to work. */
# pragma GCC visibility push(hidden)
#include <assert.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <dl-machine.h>
#define RESOLVE_MAP(map, scope, sym, version, flags) map
#include "dynamic-link.h"
#include "get-dynamic-info.h"
/* Relocate static executable with PIE. */
void
_dl_relocate_static_pie (void)
{
struct link_map *main_map = _dl_get_dl_main_map ();
/* Figure out the run-time load address of static PIE. */
main_map->l_addr = elf_machine_load_address ();
/* Read our own dynamic section and fill in the info array. */
main_map->l_ld = ((void *) main_map->l_addr + elf_machine_dynamic ());
const ElfW(Phdr) *ph, *phdr = GL(dl_phdr);
size_t phnum = GL(dl_phnum);
for (ph = phdr; ph < &phdr[phnum]; ++ph)
if (ph->p_type == PT_DYNAMIC)
{
main_map->l_ld_readonly = (ph->p_flags & PF_W) == 0;
break;
}
elf_get_dynamic_info (main_map, false, true);
# ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
ELF_MACHINE_BEFORE_RTLD_RELOC (main_map, main_map->l_info);
# endif
/* Relocate ourselves so we can do normal function calls and
data access using the global offset table. */
ELF_DYNAMIC_RELOCATE (main_map, NULL, 0, 0, 0);
main_map->l_relocated = 1;
/* Initialize _r_debug. */
struct r_debug *r = _dl_debug_initialize (0, LM_ID_BASE);
r->r_state = RT_CONSISTENT;
/* Set up debugging before the debugger is notified for the first
time. */
# ifdef ELF_MACHINE_DEBUG_SETUP
/* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */
ELF_MACHINE_DEBUG_SETUP (main_map, r);
# else
if (main_map->l_info[DT_DEBUG] != NULL)
/* There is a DT_DEBUG entry in the dynamic section. Fill it in
with the run-time address of the r_debug structure */
main_map->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r;
# endif
}
#endif