Use dlsym to check if libdl is needed for plugin
Commit Message
config/plugins.m4 has
if test "$plugins" = "yes"; then
AC_SEARCH_LIBS([dlopen], [dl])
fi
Plugin uses dlsym, but libasan.so only intercepts dlopen, not dlsym:
[hjl@gnu-tools-1 binutils-text]$ nm -D /lib64/libasan.so.4| grep " dl"
0000000000038580 W dlclose
U dl_iterate_phdr
000000000004dc50 W dlopen
U dlsym
U dlvsym
[hjl@gnu-tools-1 binutils-text]$
Testing dlopen for libdl leads to false negative when -fsanitize=address
is used. It results in link failure:
../bfd/.libs/libbfd.a(plugin.o): undefined reference to symbol 'dlsym@@GLIBC_2.16'
dlsym should be used to check if libdl is needed for plugin.
OK for master?
H.J.
---
bfd/
PR gas/22318
* configure: Regenerated.
binutils/
PR gas/22318
* configure: Regenerated.
config/
* plugins.m4 (AC_PLUGINS): Use dlsym to check if libdl is needed.
gas/
PR gas/22318
* configure: Regenerated.
gprof/
PR gas/22318
* configure: Regenerated.
ld/
PR gas/22318
* configure: Regenerated.
---
bfd/configure | 24 ++++++++++++------------
binutils/configure | 24 ++++++++++++------------
config/plugins.m4 | 2 +-
gas/configure | 24 ++++++++++++------------
gprof/configure | 24 ++++++++++++------------
ld/configure | 24 ++++++++++++------------
6 files changed, 61 insertions(+), 61 deletions(-)
Comments
On Wed, Oct 18, 2017 at 5:25 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> config/plugins.m4 has
>
> if test "$plugins" = "yes"; then
> AC_SEARCH_LIBS([dlopen], [dl])
> fi
>
> Plugin uses dlsym, but libasan.so only intercepts dlopen, not dlsym:
>
> [hjl@gnu-tools-1 binutils-text]$ nm -D /lib64/libasan.so.4| grep " dl"
> 0000000000038580 W dlclose
> U dl_iterate_phdr
> 000000000004dc50 W dlopen
> U dlsym
> U dlvsym
> [hjl@gnu-tools-1 binutils-text]$
>
> Testing dlopen for libdl leads to false negative when -fsanitize=address
> is used. It results in link failure:
>
> ../bfd/.libs/libbfd.a(plugin.o): undefined reference to symbol 'dlsym@@GLIBC_2.16'
>
> dlsym should be used to check if libdl is needed for plugin.
>
> OK for master?
>
> H.J.
> ---
> bfd/
>
> PR gas/22318
> * configure: Regenerated.
>
> binutils/
>
> PR gas/22318
> * configure: Regenerated.
>
> config/
>
> * plugins.m4 (AC_PLUGINS): Use dlsym to check if libdl is needed.
>
> gas/
>
> PR gas/22318
> * configure: Regenerated.
>
> gprof/
>
> PR gas/22318
> * configure: Regenerated.
>
> ld/
>
> PR gas/22318
> * configure: Regenerated.
> diff --git a/config/plugins.m4 b/config/plugins.m4
> index 513c690e1b..c6acebc1ca 100644
> --- a/config/plugins.m4
> +++ b/config/plugins.m4
> @@ -16,6 +16,6 @@ AC_DEFUN([AC_PLUGINS],
> [plugins=$maybe_plugins]
> )
> if test "$plugins" = "yes"; then
> - AC_SEARCH_LIBS([dlopen], [dl])
> + AC_SEARCH_LIBS([dlsym], [dl])
> fi
> ])
If there are no objections, I will check into binutils master branch this week.
@@ -11826,9 +11826,9 @@ else
fi
if test "$plugins" = "yes"; then
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlopen" >&5
-$as_echo_n "checking for library containing dlopen... " >&6; }
-if test "${ac_cv_search_dlopen+set}" = set; then :
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlsym" >&5
+$as_echo_n "checking for library containing dlsym... " >&6; }
+if test "${ac_cv_search_dlsym+set}" = set; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
@@ -11841,11 +11841,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
#ifdef __cplusplus
extern "C"
#endif
-char dlopen ();
+char dlsym ();
int
main ()
{
-return dlopen ();
+return dlsym ();
;
return 0;
}
@@ -11858,25 +11858,25 @@ for ac_lib in '' dl; do
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
- ac_cv_search_dlopen=$ac_res
+ ac_cv_search_dlsym=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
- if test "${ac_cv_search_dlopen+set}" = set; then :
+ if test "${ac_cv_search_dlsym+set}" = set; then :
break
fi
done
-if test "${ac_cv_search_dlopen+set}" = set; then :
+if test "${ac_cv_search_dlsym+set}" = set; then :
else
- ac_cv_search_dlopen=no
+ ac_cv_search_dlsym=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlopen" >&5
-$as_echo "$ac_cv_search_dlopen" >&6; }
-ac_res=$ac_cv_search_dlopen
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlsym" >&5
+$as_echo "$ac_cv_search_dlsym" >&6; }
+ac_res=$ac_cv_search_dlsym
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
@@ -11622,9 +11622,9 @@ else
fi
if test "$plugins" = "yes"; then
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlopen" >&5
-$as_echo_n "checking for library containing dlopen... " >&6; }
-if test "${ac_cv_search_dlopen+set}" = set; then :
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlsym" >&5
+$as_echo_n "checking for library containing dlsym... " >&6; }
+if test "${ac_cv_search_dlsym+set}" = set; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
@@ -11637,11 +11637,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
#ifdef __cplusplus
extern "C"
#endif
-char dlopen ();
+char dlsym ();
int
main ()
{
-return dlopen ();
+return dlsym ();
;
return 0;
}
@@ -11654,25 +11654,25 @@ for ac_lib in '' dl; do
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
- ac_cv_search_dlopen=$ac_res
+ ac_cv_search_dlsym=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
- if test "${ac_cv_search_dlopen+set}" = set; then :
+ if test "${ac_cv_search_dlsym+set}" = set; then :
break
fi
done
-if test "${ac_cv_search_dlopen+set}" = set; then :
+if test "${ac_cv_search_dlsym+set}" = set; then :
else
- ac_cv_search_dlopen=no
+ ac_cv_search_dlsym=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlopen" >&5
-$as_echo "$ac_cv_search_dlopen" >&6; }
-ac_res=$ac_cv_search_dlopen
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlsym" >&5
+$as_echo "$ac_cv_search_dlsym" >&6; }
+ac_res=$ac_cv_search_dlsym
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
@@ -16,6 +16,6 @@ AC_DEFUN([AC_PLUGINS],
[plugins=$maybe_plugins]
)
if test "$plugins" = "yes"; then
- AC_SEARCH_LIBS([dlopen], [dl])
+ AC_SEARCH_LIBS([dlsym], [dl])
fi
])
@@ -11383,9 +11383,9 @@ else
fi
if test "$plugins" = "yes"; then
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlopen" >&5
-$as_echo_n "checking for library containing dlopen... " >&6; }
-if test "${ac_cv_search_dlopen+set}" = set; then :
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlsym" >&5
+$as_echo_n "checking for library containing dlsym... " >&6; }
+if test "${ac_cv_search_dlsym+set}" = set; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
@@ -11398,11 +11398,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
#ifdef __cplusplus
extern "C"
#endif
-char dlopen ();
+char dlsym ();
int
main ()
{
-return dlopen ();
+return dlsym ();
;
return 0;
}
@@ -11415,25 +11415,25 @@ for ac_lib in '' dl; do
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
- ac_cv_search_dlopen=$ac_res
+ ac_cv_search_dlsym=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
- if test "${ac_cv_search_dlopen+set}" = set; then :
+ if test "${ac_cv_search_dlsym+set}" = set; then :
break
fi
done
-if test "${ac_cv_search_dlopen+set}" = set; then :
+if test "${ac_cv_search_dlsym+set}" = set; then :
else
- ac_cv_search_dlopen=no
+ ac_cv_search_dlsym=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlopen" >&5
-$as_echo "$ac_cv_search_dlopen" >&6; }
-ac_res=$ac_cv_search_dlopen
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlsym" >&5
+$as_echo "$ac_cv_search_dlsym" >&6; }
+ac_res=$ac_cv_search_dlsym
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
@@ -11298,9 +11298,9 @@ else
fi
if test "$plugins" = "yes"; then
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlopen" >&5
-$as_echo_n "checking for library containing dlopen... " >&6; }
-if test "${ac_cv_search_dlopen+set}" = set; then :
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlsym" >&5
+$as_echo_n "checking for library containing dlsym... " >&6; }
+if test "${ac_cv_search_dlsym+set}" = set; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
@@ -11313,11 +11313,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
#ifdef __cplusplus
extern "C"
#endif
-char dlopen ();
+char dlsym ();
int
main ()
{
-return dlopen ();
+return dlsym ();
;
return 0;
}
@@ -11330,25 +11330,25 @@ for ac_lib in '' dl; do
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
- ac_cv_search_dlopen=$ac_res
+ ac_cv_search_dlsym=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
- if test "${ac_cv_search_dlopen+set}" = set; then :
+ if test "${ac_cv_search_dlsym+set}" = set; then :
break
fi
done
-if test "${ac_cv_search_dlopen+set}" = set; then :
+if test "${ac_cv_search_dlsym+set}" = set; then :
else
- ac_cv_search_dlopen=no
+ ac_cv_search_dlsym=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlopen" >&5
-$as_echo "$ac_cv_search_dlopen" >&6; }
-ac_res=$ac_cv_search_dlopen
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlsym" >&5
+$as_echo "$ac_cv_search_dlsym" >&6; }
+ac_res=$ac_cv_search_dlsym
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
@@ -15137,9 +15137,9 @@ else
fi
if test "$plugins" = "yes"; then
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlopen" >&5
-$as_echo_n "checking for library containing dlopen... " >&6; }
-if test "${ac_cv_search_dlopen+set}" = set; then :
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing dlsym" >&5
+$as_echo_n "checking for library containing dlsym... " >&6; }
+if test "${ac_cv_search_dlsym+set}" = set; then :
$as_echo_n "(cached) " >&6
else
ac_func_search_save_LIBS=$LIBS
@@ -15152,11 +15152,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
#ifdef __cplusplus
extern "C"
#endif
-char dlopen ();
+char dlsym ();
int
main ()
{
-return dlopen ();
+return dlsym ();
;
return 0;
}
@@ -15169,25 +15169,25 @@ for ac_lib in '' dl; do
LIBS="-l$ac_lib $ac_func_search_save_LIBS"
fi
if ac_fn_c_try_link "$LINENO"; then :
- ac_cv_search_dlopen=$ac_res
+ ac_cv_search_dlsym=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
conftest$ac_exeext
- if test "${ac_cv_search_dlopen+set}" = set; then :
+ if test "${ac_cv_search_dlsym+set}" = set; then :
break
fi
done
-if test "${ac_cv_search_dlopen+set}" = set; then :
+if test "${ac_cv_search_dlsym+set}" = set; then :
else
- ac_cv_search_dlopen=no
+ ac_cv_search_dlsym=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlopen" >&5
-$as_echo "$ac_cv_search_dlopen" >&6; }
-ac_res=$ac_cv_search_dlopen
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_dlsym" >&5
+$as_echo "$ac_cv_search_dlsym" >&6; }
+ac_res=$ac_cv_search_dlsym
if test "$ac_res" != no; then :
test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"