1/* Support for relocating static PIE.
2 Copyright (C) 2017-2020 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#if ENABLE_STATIC_PIE
20#include <unistd.h>
21#include <ldsodefs.h>
22#include "dynamic-link.h"
23
24/* Relocate static executable with PIE. */
25
26void
27_dl_relocate_static_pie (void)
28{
29 struct link_map *main_map = _dl_get_dl_main_map ();
30
31# define STATIC_PIE_BOOTSTRAP
32# define BOOTSTRAP_MAP (main_map)
33# define RESOLVE_MAP(sym, version, flags) BOOTSTRAP_MAP
34# include "dynamic-link.h"
35
36 /* Figure out the run-time load address of static PIE. */
37 main_map->l_addr = elf_machine_load_address ();
38
39 /* Read our own dynamic section and fill in the info array. */
40 main_map->l_ld = ((void *) main_map->l_addr + elf_machine_dynamic ());
41 elf_get_dynamic_info (main_map, NULL);
42
43# ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
44 ELF_MACHINE_BEFORE_RTLD_RELOC (main_map->l_info);
45# endif
46
47 /* Relocate ourselves so we can do normal function calls and
48 data access using the global offset table. */
49 ELF_DYNAMIC_RELOCATE (main_map, 0, 0, 0);
50 main_map->l_relocated = 1;
51
52 /* Initialize _r_debug. */
53 struct r_debug *r = _dl_debug_initialize (0, LM_ID_BASE);
54 r->r_state = RT_CONSISTENT;
55
56 /* Set up debugging before the debugger is notified for the first
57 time. */
58# ifdef ELF_MACHINE_DEBUG_SETUP
59 /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */
60 ELF_MACHINE_DEBUG_SETUP (main_map, r);
61# else
62 if (main_map->l_info[DT_DEBUG] != NULL)
63 /* There is a DT_DEBUG entry in the dynamic section. Fill it in
64 with the run-time address of the r_debug structure */
65 main_map->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r;
66# endif
67}
68#endif
69