void
_dl_relocate_static_pie (void)
{
struct link_map *main_map = _dl_get_dl_main_map ();
# define STATIC_PIE_BOOTSTRAP
# define BOOTSTRAP_MAP (main_map)
# define RESOLVE_MAP(sym, version, flags) BOOTSTRAP_MAP
# include "dynamic-link.h"
/* 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 ());
elf_get_dynamic_info (main_map, NULL);
# ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
ELF_MACHINE_BEFORE_RTLD_RELOC (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, 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
}
void
_dl_relocate_object (struct link_map *l, struct link_map *scope[], int lazy)
{
if (l->l_relocated)
return;
if (l->l_info[DT_TEXTREL])
{
/* 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)
{
caddr_t mapstart = ((caddr_t) l->l_addr +
(ph->p_vaddr & ~(_dl_pagesize - 1)));
caddr_t mapend = ((caddr_t) l->l_addr +
((ph->p_vaddr + ph->p_memsz + _dl_pagesize - 1)
& ~(_dl_pagesize - 1)));
if (__mprotect (mapstart, mapend - mapstart,
PROT_READ|PROT_WRITE) < 0)
_dl_signal_error (errno, l->l_name,
"cannot make segment writable for relocation");
}
}
{
/* Do the actual relocation of the object's GOT and other data. */
const char *strtab /* String table object symbols. */
= ((void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr);
/* This macro is used as a callback from the ELF_DYNAMIC_RELOCATE code. */
#define RESOLVE(ref, flags) \
(_dl_lookup_symbol (strtab + (*ref)->st_name, ref, scope, \
l->l_name, flags))
#include "dynamic-link.h"
ELF_DYNAMIC_RELOCATE (l, lazy);
}
/* Set up the PLT so its unrelocated entries will jump to
_dl_runtime_resolve (dl-runtime.c), which will relocate them. */
elf_machine_runtime_setup (l, lazy);
/* Mark the object so we know ths work has been done. */
l->l_relocated = 1;
if (l->l_info[DT_TEXTREL])
{
/* Undo the protection change we made before relocating. */
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)
{
caddr_t mapstart = ((caddr_t) l->l_addr +
(ph->p_vaddr & ~(_dl_pagesize - 1)));
caddr_t mapend = ((caddr_t) l->l_addr +
((ph->p_vaddr + ph->p_memsz + _dl_pagesize - 1)
& ~(_dl_pagesize - 1)));
int prot = 0;
if (ph->p_flags & PF_R)
prot |= PROT_READ;
if (ph->p_flags & PF_X)
prot |= PROT_EXEC;
if (__mprotect (mapstart, mapend - mapstart, prot) < 0)
_dl_signal_error (errno, l->l_name,
"can't restore segment prot after reloc");
}
}
}
