mirror of
https://github.com/autc04/Retro68.git
synced 2024-12-05 08:51:48 +00:00
212 lines
7.1 KiB
C
212 lines
7.1 KiB
C
/* Relocate a shared object and resolve its references to other loaded objects.
|
|
Copyright (C) 1995,96,97,98,99,2000,2001 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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#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"
|
|
|
|
/* Statistics function. */
|
|
unsigned long int _dl_num_cache_relocations;
|
|
|
|
|
|
void
|
|
_dl_relocate_object (struct link_map *l, struct r_scope_elem *scope[],
|
|
int lazy, int consider_profiling)
|
|
{
|
|
struct textrels
|
|
{
|
|
caddr_t start;
|
|
size_t len;
|
|
int prot;
|
|
struct textrels *next;
|
|
} *textrels = NULL;
|
|
/* Initialize it to make the compiler happy. */
|
|
const char *errstring = NULL;
|
|
|
|
if (l->l_relocated)
|
|
return;
|
|
|
|
/* If DT_BIND_NOW is set relocate all references in this object. We
|
|
do not do this if we are profiling, of course. */
|
|
if (!consider_profiling
|
|
&& __builtin_expect (l->l_info[DT_BIND_NOW] != NULL, 0))
|
|
lazy = 0;
|
|
|
|
if (__builtin_expect (_dl_debug_mask & DL_DEBUG_RELOC, 0))
|
|
_dl_printf ("\nrelocation processing: %s%s\n",
|
|
l->l_name[0] ? l->l_name : _dl_argv[0], lazy ? " (lazy)" : "");
|
|
|
|
/* DT_TEXTREL is now in level 2 and might phase out at some time.
|
|
But we rewrite the DT_FLAGS entry to a DT_TEXTREL entry to make
|
|
testing easier and therefore it will be available at all time. */
|
|
if (__builtin_expect (l->l_info[DT_TEXTREL] != NULL, 0))
|
|
{
|
|
/* Bletch. We must make read-only segments writable
|
|
long enough to relocate them. */
|
|
const ElfW(Phdr) *ph;
|
|
for (ph = l->l_phdr; ph < &l->l_phdr[l->l_phnum]; ++ph)
|
|
if (ph->p_type == PT_LOAD && (ph->p_flags & PF_W) == 0)
|
|
{
|
|
struct textrels *newp;
|
|
|
|
newp = (struct textrels *) alloca (sizeof (*newp));
|
|
newp->len = (((ph->p_vaddr + ph->p_memsz + _dl_pagesize - 1)
|
|
& ~(_dl_pagesize - 1))
|
|
- (ph->p_vaddr & ~(_dl_pagesize - 1)));
|
|
newp->start = ((ph->p_vaddr & ~(_dl_pagesize - 1))
|
|
+ (caddr_t) l->l_addr);
|
|
|
|
if (mprotect (newp->start, newp->len, PROT_READ|PROT_WRITE) < 0)
|
|
{
|
|
errstring = N_("cannot make segment writable for relocation");
|
|
call_error:
|
|
_dl_signal_error (errno, l->l_name, NULL, errstring);
|
|
}
|
|
|
|
#if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
|
|
newp->prot = (PF_TO_PROT
|
|
>> ((ph->p_flags & (PF_R | PF_W | PF_X)) * 4)) & 0xf;
|
|
#else
|
|
newp->prot = 0;
|
|
if (ph->p_flags & PF_R)
|
|
newp->prot |= PROT_READ;
|
|
if (ph->p_flags & PF_W)
|
|
newp->prot |= PROT_WRITE;
|
|
if (ph->p_flags & PF_X)
|
|
newp->prot |= PROT_EXEC;
|
|
#endif
|
|
newp->next = textrels;
|
|
textrels = newp;
|
|
}
|
|
}
|
|
|
|
{
|
|
/* Do the actual relocation of the object's GOT and other data. */
|
|
|
|
/* This macro is used as a callback from the ELF_DYNAMIC_RELOCATE code. */
|
|
#define RESOLVE_MAP(ref, version, r_type, scope) \
|
|
(ELFW(ST_BIND) ((*ref)->st_info) != STB_LOCAL \
|
|
? ((__builtin_expect ((*ref) == map->l_lookup_cache.sym, 0) \
|
|
&& elf_machine_type_class (r_type) == map->l_lookup_cache.type_class)\
|
|
? (++_dl_num_cache_relocations, \
|
|
(*ref) = map->l_lookup_cache.ret, \
|
|
map->l_lookup_cache.value) \
|
|
: ({ lookup_t _lr; \
|
|
int _tc = elf_machine_type_class (r_type); \
|
|
map->l_lookup_cache.type_class = _tc; \
|
|
map->l_lookup_cache.sym = (*ref); \
|
|
_lr = ((version) != NULL && (version)->hash != 0 \
|
|
? _dl_lookup_versioned_symbol (strtab + (*ref)->st_name, \
|
|
map, (ref), scope, \
|
|
(version), _tc, 0) \
|
|
: _dl_lookup_symbol (strtab + (*ref)->st_name, map, (ref),\
|
|
scope, _tc, 0)); \
|
|
map->l_lookup_cache.ret = (*ref); \
|
|
map->l_lookup_cache.value = _lr; })) \
|
|
: map)
|
|
#define RESOLVE(ref, version, r_type, scope) \
|
|
(ELFW(ST_BIND) ((*ref)->st_info) != STB_LOCAL \
|
|
? ((__builtin_expect ((*ref) == map->l_lookup_cache.sym, 0) \
|
|
&& elf_machine_type_class (r_type) == map->l_lookup_cache.type_class)\
|
|
? (++_dl_num_cache_relocations, \
|
|
(*ref) = map->l_lookup_cache.ret, \
|
|
map->l_lookup_cache.value) \
|
|
: ({ lookup_t _lr; \
|
|
int _tc = elf_machine_type_class (r_type); \
|
|
map->l_lookup_cache.type_class = _tc; \
|
|
map->l_lookup_cache.sym = (*ref); \
|
|
_lr = ((version) != NULL && (version)->hash != 0 \
|
|
? _dl_lookup_versioned_symbol (strtab + (*ref)->st_name, \
|
|
map, (ref), scope, \
|
|
(version), _tc, 0) \
|
|
: _dl_lookup_symbol (strtab + (*ref)->st_name, map, (ref),\
|
|
scope, _tc, 0)); \
|
|
map->l_lookup_cache.ret = (*ref); \
|
|
map->l_lookup_cache.value = _lr; })) \
|
|
: map->l_addr)
|
|
|
|
#include "dynamic-link.h"
|
|
|
|
ELF_DYNAMIC_RELOCATE (l, lazy, consider_profiling);
|
|
|
|
if (__builtin_expect (consider_profiling, 0))
|
|
{
|
|
/* Allocate the array which will contain the already found
|
|
relocations. If the shared object lacks a PLT (for example
|
|
if it only contains lead function) the l_info[DT_PLTRELSZ]
|
|
will be NULL. */
|
|
if (l->l_info[DT_PLTRELSZ] == NULL)
|
|
{
|
|
errstring = N_("%s: profiler found no PLTREL in object %s\n");
|
|
fatal:
|
|
_dl_fatal_printf (errstring,
|
|
_dl_argv[0] ?: "<program name unknown>",
|
|
l->l_name);
|
|
}
|
|
|
|
l->l_reloc_result =
|
|
(ElfW(Addr) *) calloc (sizeof (ElfW(Addr)),
|
|
l->l_info[DT_PLTRELSZ]->d_un.d_val);
|
|
if (l->l_reloc_result == NULL)
|
|
{
|
|
errstring = N_("\
|
|
%s: profiler out of memory shadowing PLTREL of %s\n");
|
|
goto fatal;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Mark the object so we know this work has been done. */
|
|
l->l_relocated = 1;
|
|
|
|
/* Undo the segment protection changes. */
|
|
while (__builtin_expect (textrels != NULL, 0))
|
|
{
|
|
if (mprotect (textrels->start, textrels->len, textrels->prot) < 0)
|
|
{
|
|
errstring = N_("cannot restore segment prot after reloc");
|
|
goto call_error;
|
|
}
|
|
|
|
textrels = textrels->next;
|
|
}
|
|
}
|
|
|
|
#include <machine/dl-machine.h>
|
|
|
|
void
|
|
internal_function
|
|
_dl_reloc_bad_type (struct link_map *map, unsigned int type, int plt)
|
|
{
|
|
/* XXX We cannot translate these messages. */
|
|
static const char msg[2][32] = { "unexpected reloc type",
|
|
"unexpected PLT reloc type" };
|
|
char msgbuf[sizeof (msg[0])];
|
|
|
|
strcpy (msgbuf, msg[plt]);
|
|
|
|
_dl_signal_error (0, map->l_name, NULL, msgbuf);
|
|
}
|