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Set up the data structures for vDSO in libc.a

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This commit is contained in:
H.J. Lu 2012-10-05 10:20:39 -07:00
parent 28234b077e
commit 9cee558564
6 changed files with 307 additions and 238 deletions
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15
ChangeLog
View File

@ -1,3 +1,18 @@
2012-10-05 H.J. Lu <hongjiu.lu@intel.com>
[BZ #14557]
* elf/dl-support.c (_dl_sysinfo_map): New.
Include "get-dynamic-info.h" and "setup-vdso.h".
(_dl_non_dynamic_init): Call setup_vdso.
* elf/dynamic-link.h: Don't include <assert.h>.
(elf_get_dynamic_info): Moved to ...
* elf/get-dynamic-info.h: Here. New file.
* elf/dynamic-link.h: Include "get-dynamic-info.h".
* elf/rtld.c (dl_main): Break out vDSO setup code into ...
* elf/setup-vdso.h: Here. New file.
* elf/rtld.c: Include "setup-vdso.h".
(dl_main): Call setup_vdso.
2012-10-05 Joseph Myers <joseph@codesourcery.com>
* math/libm-test.inc: List nexttoward, cimag, clog10, conf and

9
elf/dl-support.c
View File

@ -161,6 +161,11 @@ uintptr_t _dl_sysinfo = DL_SYSINFO_DEFAULT;
#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO
/* Address of the ELF headers in the vsyscall page. */
const ElfW(Ehdr) *_dl_sysinfo_dso;
struct link_map *_dl_sysinfo_map;
# include "get-dynamic-info.h"
# include "setup-vdso.h"
#endif
/* During the program run we must not modify the global data of
@ -266,6 +271,10 @@ _dl_non_dynamic_init (void)
_dl_verbose = *(getenv ("LD_WARN") ?: "") == '\0' ? 0 : 1;
/* Set up the data structures for the system-supplied DSO early,
so they can influence _dl_init_paths. */
setup_vdso (NULL, NULL);
/* Initialize the data structures for the search paths for shared
objects. */
_dl_init_paths (getenv ("LD_LIBRARY_PATH"));

145
elf/dynamic-link.h
View File

@ -42,7 +42,6 @@
int internal_function _dl_try_allocate_static_tls (struct link_map *map);
#include <elf.h>
#include <assert.h>
#ifdef RESOLVE_MAP
/* We pass reloc_addr as a pointer to void, as opposed to a pointer to
@ -88,149 +87,7 @@ elf_machine_lazy_rel (struct link_map *map,
#include <dl-machine.h>
/* Read the dynamic section at DYN and fill in INFO with indices DT_*. */
#ifndef RESOLVE_MAP
static
#else
auto
#endif
inline void __attribute__ ((unused, always_inline))
elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
{
ElfW(Dyn) *dyn = l->l_ld;
ElfW(Dyn) **info;
#if __ELF_NATIVE_CLASS == 32
typedef Elf32_Word d_tag_utype;
#elif __ELF_NATIVE_CLASS == 64
typedef Elf64_Xword d_tag_utype;
#endif
#ifndef RTLD_BOOTSTRAP
if (dyn == NULL)
return;
#endif
info = l->l_info;
while (dyn->d_tag != DT_NULL)
{
if ((d_tag_utype) dyn->d_tag < DT_NUM)
info[dyn->d_tag] = dyn;
else if (dyn->d_tag >= DT_LOPROC &&
dyn->d_tag < DT_LOPROC + DT_THISPROCNUM)
info[dyn->d_tag - DT_LOPROC + DT_NUM] = dyn;
else if ((d_tag_utype) DT_VERSIONTAGIDX (dyn->d_tag) < DT_VERSIONTAGNUM)
info[VERSYMIDX (dyn->d_tag)] = dyn;
else if ((d_tag_utype) DT_EXTRATAGIDX (dyn->d_tag) < DT_EXTRANUM)
info[DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM] = dyn;
else if ((d_tag_utype) DT_VALTAGIDX (dyn->d_tag) < DT_VALNUM)
info[DT_VALTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM + DT_EXTRANUM] = dyn;
else if ((d_tag_utype) DT_ADDRTAGIDX (dyn->d_tag) < DT_ADDRNUM)
info[DT_ADDRTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] = dyn;
++dyn;
}
#define DL_RO_DYN_TEMP_CNT 8
#ifndef DL_RO_DYN_SECTION
/* Don't adjust .dynamic unnecessarily. */
if (l->l_addr != 0)
{
ElfW(Addr) l_addr = l->l_addr;
int cnt = 0;
# define ADJUST_DYN_INFO(tag) \
do \
if (info[tag] != NULL) \
{ \
if (temp) \
{ \
temp[cnt].d_tag = info[tag]->d_tag; \
temp[cnt].d_un.d_ptr = info[tag]->d_un.d_ptr + l_addr; \
info[tag] = temp + cnt++; \
} \
else \
info[tag]->d_un.d_ptr += l_addr; \
} \
while (0)
ADJUST_DYN_INFO (DT_HASH);
ADJUST_DYN_INFO (DT_PLTGOT);
ADJUST_DYN_INFO (DT_STRTAB);
ADJUST_DYN_INFO (DT_SYMTAB);
# if ! ELF_MACHINE_NO_RELA
ADJUST_DYN_INFO (DT_RELA);
# endif
# if ! ELF_MACHINE_NO_REL
ADJUST_DYN_INFO (DT_REL);
# endif
ADJUST_DYN_INFO (DT_JMPREL);
ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM));
ADJUST_DYN_INFO (DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM);
# undef ADJUST_DYN_INFO
assert (cnt <= DL_RO_DYN_TEMP_CNT);
}
#endif
if (info[DT_PLTREL] != NULL)
{
#if ELF_MACHINE_NO_RELA
assert (info[DT_PLTREL]->d_un.d_val == DT_REL);
#elif ELF_MACHINE_NO_REL
assert (info[DT_PLTREL]->d_un.d_val == DT_RELA);
#else
assert (info[DT_PLTREL]->d_un.d_val == DT_REL
|| info[DT_PLTREL]->d_un.d_val == DT_RELA);
#endif
}
#if ! ELF_MACHINE_NO_RELA
if (info[DT_RELA] != NULL)
assert (info[DT_RELAENT]->d_un.d_val == sizeof (ElfW(Rela)));
# endif
# if ! ELF_MACHINE_NO_REL
if (info[DT_REL] != NULL)
assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel)));
#endif
#ifdef RTLD_BOOTSTRAP
/* Only the bind now flags are allowed. */
assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL
|| (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0);
assert (info[DT_FLAGS] == NULL
|| (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0);
/* Flags must not be set for ld.so. */
assert (info[DT_RUNPATH] == NULL);
assert (info[DT_RPATH] == NULL);
#else
if (info[DT_FLAGS] != NULL)
{
/* Flags are used. Translate to the old form where available.
Since these l_info entries are only tested for NULL pointers it
is ok if they point to the DT_FLAGS entry. */
l->l_flags = info[DT_FLAGS]->d_un.d_val;
if (l->l_flags & DF_SYMBOLIC)
info[DT_SYMBOLIC] = info[DT_FLAGS];
if (l->l_flags & DF_TEXTREL)
info[DT_TEXTREL] = info[DT_FLAGS];
if (l->l_flags & DF_BIND_NOW)
info[DT_BIND_NOW] = info[DT_FLAGS];
}
if (info[VERSYMIDX (DT_FLAGS_1)] != NULL)
{
l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val;
if (l->l_flags_1 & DF_1_NOW)
info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)];
}
if (info[DT_RUNPATH] != NULL)
/* If both RUNPATH and RPATH are given, the latter is ignored. */
info[DT_RPATH] = NULL;
#endif
}
#include "get-dynamic-info.h"
#ifdef RESOLVE_MAP

161
elf/get-dynamic-info.h Normal file
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@ -0,0 +1,161 @@
/* Read the dynamic section at DYN and fill in INFO with indices DT_*.
Copyright (C) 2012 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
<http://www.gnu.org/licenses/>. */
#include <assert.h>
#ifndef RESOLVE_MAP
static
#else
auto
#endif
inline void __attribute__ ((unused, always_inline))
elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
{
ElfW(Dyn) *dyn = l->l_ld;
ElfW(Dyn) **info;
#if __ELF_NATIVE_CLASS == 32
typedef Elf32_Word d_tag_utype;
#elif __ELF_NATIVE_CLASS == 64
typedef Elf64_Xword d_tag_utype;
#endif
#ifndef RTLD_BOOTSTRAP
if (dyn == NULL)
return;
#endif
info = l->l_info;
while (dyn->d_tag != DT_NULL)
{
if ((d_tag_utype) dyn->d_tag < DT_NUM)
info[dyn->d_tag] = dyn;
else if (dyn->d_tag >= DT_LOPROC &&
dyn->d_tag < DT_LOPROC + DT_THISPROCNUM)
info[dyn->d_tag - DT_LOPROC + DT_NUM] = dyn;
else if ((d_tag_utype) DT_VERSIONTAGIDX (dyn->d_tag) < DT_VERSIONTAGNUM)
info[VERSYMIDX (dyn->d_tag)] = dyn;
else if ((d_tag_utype) DT_EXTRATAGIDX (dyn->d_tag) < DT_EXTRANUM)
info[DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM] = dyn;
else if ((d_tag_utype) DT_VALTAGIDX (dyn->d_tag) < DT_VALNUM)
info[DT_VALTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM + DT_EXTRANUM] = dyn;
else if ((d_tag_utype) DT_ADDRTAGIDX (dyn->d_tag) < DT_ADDRNUM)
info[DT_ADDRTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] = dyn;
++dyn;
}
#define DL_RO_DYN_TEMP_CNT 8
#ifndef DL_RO_DYN_SECTION
/* Don't adjust .dynamic unnecessarily. */
if (l->l_addr != 0)
{
ElfW(Addr) l_addr = l->l_addr;
int cnt = 0;
# define ADJUST_DYN_INFO(tag) \
do \
if (info[tag] != NULL) \
{ \
if (temp) \
{ \
temp[cnt].d_tag = info[tag]->d_tag; \
temp[cnt].d_un.d_ptr = info[tag]->d_un.d_ptr + l_addr; \
info[tag] = temp + cnt++; \
} \
else \
info[tag]->d_un.d_ptr += l_addr; \
} \
while (0)
ADJUST_DYN_INFO (DT_HASH);
ADJUST_DYN_INFO (DT_PLTGOT);
ADJUST_DYN_INFO (DT_STRTAB);
ADJUST_DYN_INFO (DT_SYMTAB);
# if ! ELF_MACHINE_NO_RELA
ADJUST_DYN_INFO (DT_RELA);
# endif
# if ! ELF_MACHINE_NO_REL
ADJUST_DYN_INFO (DT_REL);
# endif
ADJUST_DYN_INFO (DT_JMPREL);
ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM));
ADJUST_DYN_INFO (DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM
+ DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM);
# undef ADJUST_DYN_INFO
assert (cnt <= DL_RO_DYN_TEMP_CNT);
}
#endif
if (info[DT_PLTREL] != NULL)
{
#if ELF_MACHINE_NO_RELA
assert (info[DT_PLTREL]->d_un.d_val == DT_REL);
#elif ELF_MACHINE_NO_REL
assert (info[DT_PLTREL]->d_un.d_val == DT_RELA);
#else
assert (info[DT_PLTREL]->d_un.d_val == DT_REL
|| info[DT_PLTREL]->d_un.d_val == DT_RELA);
#endif
}
#if ! ELF_MACHINE_NO_RELA
if (info[DT_RELA] != NULL)
assert (info[DT_RELAENT]->d_un.d_val == sizeof (ElfW(Rela)));
# endif
# if ! ELF_MACHINE_NO_REL
if (info[DT_REL] != NULL)
assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel)));
#endif
#ifdef RTLD_BOOTSTRAP
/* Only the bind now flags are allowed. */
assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL
|| (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0);
assert (info[DT_FLAGS] == NULL
|| (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0);
/* Flags must not be set for ld.so. */
assert (info[DT_RUNPATH] == NULL);
assert (info[DT_RPATH] == NULL);
#else
if (info[DT_FLAGS] != NULL)
{
/* Flags are used. Translate to the old form where available.
Since these l_info entries are only tested for NULL pointers it
is ok if they point to the DT_FLAGS entry. */
l->l_flags = info[DT_FLAGS]->d_un.d_val;
if (l->l_flags & DF_SYMBOLIC)
info[DT_SYMBOLIC] = info[DT_FLAGS];
if (l->l_flags & DF_TEXTREL)
info[DT_TEXTREL] = info[DT_FLAGS];
if (l->l_flags & DF_BIND_NOW)
info[DT_BIND_NOW] = info[DT_FLAGS];
}
if (info[VERSYMIDX (DT_FLAGS_1)] != NULL)
{
l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val;
if (l->l_flags_1 & DF_1_NOW)
info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)];
}
if (info[DT_RUNPATH] != NULL)
/* If both RUNPATH and RPATH are given, the latter is ignored. */
info[DT_RPATH] = NULL;
#endif
}

96
elf/rtld.c
View File

@ -873,6 +873,7 @@ security_init (void)
_dl_random = NULL;
}
#include "setup-vdso.h"
/* The library search path. */
static const char *library_path attribute_relro;
@ -1329,102 +1330,9 @@ of this helper program; chances are you did not intend to run this program.\n\
}
struct link_map **first_preload = &GL(dl_rtld_map).l_next;
#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO
/* Set up the data structures for the system-supplied DSO early,
so they can influence _dl_init_paths. */
if (GLRO(dl_sysinfo_dso) != NULL)
{
/* Do an abridged version of the work _dl_map_object_from_fd would do
to map in the object. It's already mapped and prelinked (and
better be, since it's read-only and so we couldn't relocate it).
We just want our data structures to describe it as if we had just
mapped and relocated it normally. */
struct link_map *l = _dl_new_object ((char *) "", "", lt_library, NULL,
0, LM_ID_BASE);
if (__builtin_expect (l != NULL, 1))
{
static ElfW(Dyn) dyn_temp[DL_RO_DYN_TEMP_CNT] attribute_relro;
l->l_phdr = ((const void *) GLRO(dl_sysinfo_dso)
+ GLRO(dl_sysinfo_dso)->e_phoff);
l->l_phnum = GLRO(dl_sysinfo_dso)->e_phnum;
for (uint_fast16_t i = 0; i < l->l_phnum; ++i)
{
const ElfW(Phdr) *const ph = &l->l_phdr[i];
if (ph->p_type == PT_DYNAMIC)
{
l->l_ld = (void *) ph->p_vaddr;
l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn));
}
else if (ph->p_type == PT_LOAD)
{
if (! l->l_addr)
l->l_addr = ph->p_vaddr;
if (ph->p_vaddr + ph->p_memsz >= l->l_map_end)
l->l_map_end = ph->p_vaddr + ph->p_memsz;
if ((ph->p_flags & PF_X)
&& ph->p_vaddr + ph->p_memsz >= l->l_text_end)
l->l_text_end = ph->p_vaddr + ph->p_memsz;
}
else
/* There must be no TLS segment. */
assert (ph->p_type != PT_TLS);
}
l->l_map_start = (ElfW(Addr)) GLRO(dl_sysinfo_dso);
l->l_addr = l->l_map_start - l->l_addr;
l->l_map_end += l->l_addr;
l->l_text_end += l->l_addr;
l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr);
elf_get_dynamic_info (l, dyn_temp);
_dl_setup_hash (l);
l->l_relocated = 1;
/* The vDSO is always used. */
l->l_used = 1;
/* Initialize l_local_scope to contain just this map. This allows
the use of dl_lookup_symbol_x to resolve symbols within the vdso.
So we create a single entry list pointing to l_real as its only
element */
l->l_local_scope[0]->r_nlist = 1;
l->l_local_scope[0]->r_list = &l->l_real;
/* Now that we have the info handy, use the DSO image's soname
so this object can be looked up by name. Note that we do not
set l_name here. That field gives the file name of the DSO,
and this DSO is not associated with any file. */
if (l->l_info[DT_SONAME] != NULL)
{
/* Work around a kernel problem. The kernel cannot handle
addresses in the vsyscall DSO pages in writev() calls. */
const char *dsoname = ((char *) D_PTR (l, l_info[DT_STRTAB])
+ l->l_info[DT_SONAME]->d_un.d_val);
size_t len = strlen (dsoname);
char *copy = malloc (len);
if (copy == NULL)
_dl_fatal_printf ("out of memory\n");
l->l_libname->name = l->l_name = memcpy (copy, dsoname, len);
}
/* Add the vDSO to the object list. */
_dl_add_to_namespace_list (l, LM_ID_BASE);
/* Rearrange the list so this DSO appears after rtld_map. */
assert (l->l_next == NULL);
assert (l->l_prev == main_map);
GL(dl_rtld_map).l_next = l;
l->l_prev = &GL(dl_rtld_map);
first_preload = &l->l_next;
/* We have a prelinked DSO preloaded by the system. */
GLRO(dl_sysinfo_map) = l;
# ifdef NEED_DL_SYSINFO
if (GLRO(dl_sysinfo) == DL_SYSINFO_DEFAULT)
GLRO(dl_sysinfo) = GLRO(dl_sysinfo_dso)->e_entry + l->l_addr;
# endif
}
}
#endif
setup_vdso (main_map, &first_preload);
#ifdef DL_SYSDEP_OSCHECK
DL_SYSDEP_OSCHECK (_dl_fatal_printf);

119
elf/setup-vdso.h Normal file
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@ -0,0 +1,119 @@
/* Set up the data structures for the system-supplied DSO.
Copyright (C) 2012 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
<http://www.gnu.org/licenses/>. */
static inline void __attribute__ ((always_inline))
setup_vdso (struct link_map *main_map __attribute__ ((unused)),
struct link_map ***first_preload __attribute__ ((unused)))
{
#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO
if (GLRO(dl_sysinfo_dso) == NULL)
return;
/* Do an abridged version of the work _dl_map_object_from_fd would do
to map in the object. It's already mapped and prelinked (and
better be, since it's read-only and so we couldn't relocate it).
We just want our data structures to describe it as if we had just
mapped and relocated it normally. */
struct link_map *l = _dl_new_object ((char *) "", "", lt_library, NULL,
0, LM_ID_BASE);
if (__builtin_expect (l != NULL, 1))
{
static ElfW(Dyn) dyn_temp[DL_RO_DYN_TEMP_CNT] attribute_relro;
l->l_phdr = ((const void *) GLRO(dl_sysinfo_dso)
+ GLRO(dl_sysinfo_dso)->e_phoff);
l->l_phnum = GLRO(dl_sysinfo_dso)->e_phnum;
for (uint_fast16_t i = 0; i < l->l_phnum; ++i)
{
const ElfW(Phdr) *const ph = &l->l_phdr[i];
if (ph->p_type == PT_DYNAMIC)
{
l->l_ld = (void *) ph->p_vaddr;
l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn));
}
else if (ph->p_type == PT_LOAD)
{
if (! l->l_addr)
l->l_addr = ph->p_vaddr;
if (ph->p_vaddr + ph->p_memsz >= l->l_map_end)
l->l_map_end = ph->p_vaddr + ph->p_memsz;
if ((ph->p_flags & PF_X)
&& ph->p_vaddr + ph->p_memsz >= l->l_text_end)
l->l_text_end = ph->p_vaddr + ph->p_memsz;
}
else
/* There must be no TLS segment. */
assert (ph->p_type != PT_TLS);
}
l->l_map_start = (ElfW(Addr)) GLRO(dl_sysinfo_dso);
l->l_addr = l->l_map_start - l->l_addr;
l->l_map_end += l->l_addr;
l->l_text_end += l->l_addr;
l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr);
elf_get_dynamic_info (l, dyn_temp);
_dl_setup_hash (l);
l->l_relocated = 1;
/* The vDSO is always used. */
l->l_used = 1;
/* Initialize l_local_scope to contain just this map. This allows
the use of dl_lookup_symbol_x to resolve symbols within the vdso.
So we create a single entry list pointing to l_real as its only
element */
l->l_local_scope[0]->r_nlist = 1;
l->l_local_scope[0]->r_list = &l->l_real;
/* Now that we have the info handy, use the DSO image's soname
so this object can be looked up by name. Note that we do not
set l_name here. That field gives the file name of the DSO,
and this DSO is not associated with any file. */
if (l->l_info[DT_SONAME] != NULL)
{
/* Work around a kernel problem. The kernel cannot handle
addresses in the vsyscall DSO pages in writev() calls. */
const char *dsoname = ((char *) D_PTR (l, l_info[DT_STRTAB])
+ l->l_info[DT_SONAME]->d_un.d_val);
size_t len = strlen (dsoname);
char *copy = malloc (len);
if (copy == NULL)
_dl_fatal_printf ("out of memory\n");
l->l_libname->name = l->l_name = memcpy (copy, dsoname, len);
}
/* Add the vDSO to the object list. */
_dl_add_to_namespace_list (l, LM_ID_BASE);
# ifdef IS_IN_rtld
/* Rearrange the list so this DSO appears after rtld_map. */
assert (l->l_next == NULL);
assert (l->l_prev == main_map);
GL(dl_rtld_map).l_next = l;
l->l_prev = &GL(dl_rtld_map);
*first_preload = &l->l_next;
# endif
/* We have a prelinked DSO preloaded by the system. */
GLRO(dl_sysinfo_map) = l;
# ifdef NEED_DL_SYSINFO
if (GLRO(dl_sysinfo) == DL_SYSINFO_DEFAULT)
GLRO(dl_sysinfo) = GLRO(dl_sysinfo_dso)->e_entry + l->l_addr;
# endif
}
#endif
}