mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-21 20:40:05 +00:00
4af6982e4c
Before to 490e6c62aa ('elf: Avoid nested functions in the loader
[BZ #27220]'), elf_get_dynamic_info() was defined twice on rtld.c: on
the first dynamic-link.h include and later within _dl_start(). The
former definition did not define DONT_USE_BOOTSTRAP_MAP and it is used
on setup_vdso() (since it is a global definition), while the former does
define DONT_USE_BOOTSTRAP_MAP and it is used on loader self-relocation.
With the commit change, the function is now included and defined once
instead of defined as a nested function. So rtld.c defines without
defining RTLD_BOOTSTRAP and it brokes at least powerpc32.
This patch fixes by moving the get-dynamic-info.h include out of
dynamic-link.h, which then the caller can corirectly set the expected
semantic by defining STATIC_PIE_BOOTSTRAP, RTLD_BOOTSTRAP, and/or
RESOLVE_MAP.
It also required to enable some asserts only for the loader bootstrap
to avoid issues when called from setup_vdso().
As a side note, this is another issues with nested functions: it is
not clear from pre-processed output (-E -dD) how the function will
be build and its semantic (since nested function will be local and
extra C defines may change it).
I checked on x86_64-linux-gnu (w/o --enable-static-pie),
i686-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu-power4,
aarch64-linux-gnu, arm-linux-gnu, sparc64-linux-gnu, and
s390x-linux-gnu.
Reviewed-by: Fangrui Song <maskray@google.com>
78 lines
2.8 KiB
C
78 lines
2.8 KiB
C
/* Resolve conflicts against already prelinked libraries.
|
|
Copyright (C) 2001-2021 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; see the file COPYING.LIB. If
|
|
not, see <https://www.gnu.org/licenses/>. */
|
|
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
#include <libintl.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <ldsodefs.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/param.h>
|
|
#include <sys/types.h>
|
|
#include "dynamic-link.h"
|
|
|
|
/* Used at loading time solely for prelink executable. It is not called
|
|
concurrently so it is be safe to defined as static. */
|
|
static struct link_map *resolve_conflict_map __attribute__ ((__unused__));
|
|
|
|
/* This macro is used as a callback from the ELF_DYNAMIC_RELOCATE code. */
|
|
#define RESOLVE_MAP(map, scope, ref, version, flags) (*ref = NULL, NULL)
|
|
#define RESOLVE(ref, version, flags) (*ref = NULL, 0)
|
|
#define RESOLVE_CONFLICT_FIND_MAP(map, r_offset) \
|
|
do { \
|
|
while ((resolve_conflict_map->l_map_end < (ElfW(Addr)) (r_offset)) \
|
|
|| (resolve_conflict_map->l_map_start > (ElfW(Addr)) (r_offset))) \
|
|
resolve_conflict_map = resolve_conflict_map->l_next; \
|
|
\
|
|
(map) = resolve_conflict_map; \
|
|
} while (0)
|
|
|
|
#include "dynamic-link.h"
|
|
|
|
void
|
|
_dl_resolve_conflicts (struct link_map *l, ElfW(Rela) *conflict,
|
|
ElfW(Rela) *conflictend)
|
|
{
|
|
#if ! ELF_MACHINE_NO_RELA
|
|
if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_RELOC))
|
|
_dl_debug_printf ("\nconflict processing: %s\n", DSO_FILENAME (l->l_name));
|
|
|
|
{
|
|
/* Do the conflict relocation of the object and library GOT and other
|
|
data. */
|
|
|
|
/* Prelinking makes no sense for anything but the main namespace. */
|
|
assert (l->l_ns == LM_ID_BASE);
|
|
resolve_conflict_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
|
|
|
|
/* Override these, defined in dynamic-link.h. */
|
|
#undef CHECK_STATIC_TLS
|
|
#define CHECK_STATIC_TLS(ref_map, sym_map) ((void) 0)
|
|
#undef TRY_STATIC_TLS
|
|
#define TRY_STATIC_TLS(ref_map, sym_map) (0)
|
|
|
|
GL(dl_num_cache_relocations) += conflictend - conflict;
|
|
|
|
for (; conflict < conflictend; ++conflict)
|
|
elf_machine_rela (l, NULL, conflict, NULL, NULL,
|
|
(void *) conflict->r_offset, 0);
|
|
}
|
|
#endif
|
|
}
|