tunables: Use direct syscall for access (BZ#21744)

The function maybe_enable_malloc_check, which is called by
__tunables_init, calls __access_noerrno.  It isn't problem when
symbol is is in ld.so, which has a special version of __access_noerrno
without stack protector.  But when glibc is built with stack protector,
maybe_enable_malloc_check in libc.a can't call the regular version of
__access_noerrno with stack protector.

This patch changes how Linux defines the __access_noerrno to be an
inline call instead and thus preventing defining different build
rules for ld/static and shared.

	H.J. Lu  <hongjiu.lu@intel.com>
	Adhemerval Zanella  <adhemerval.zanella@linaro.org>

	[BZ #21744]
	* elf/dl-tunables.c: Include not-errno.h header.
	* include/unistd.h (__access_noerrno): Remove definition.
	* sysdeps/unix/sysv/linux/access.c (__access_noerrno): Likewise.
	* sysdeps/generic/not-errno.h: New file.
	* sysdeps/unix/sysv/linux/not-errno.h: Likewise.

1 files changed, 0 insertions, 7 deletions

diff --git a/include/unistd.h b/include/unistd.h
index 5b2a4147dc..7f1c2ccd4b 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -182,12 +182,5 @@ extern int __getlogin_r_loginuid (char *name, size_t namesize)
 #   include <dl-unistd.h>
 #  endif
 
-#  if IS_IN (rtld) || !defined SHARED
-/* __access variant that does not set errno.  Used in very early initialization
-   code in libc.a and ld.so.  It follows access return semantics (zero for
-   sucess otherwise a value different than 0).  */
-extern __typeof (__access) __access_noerrno attribute_hidden;
-#  endif
-
 # endif
 #endif