* sysdeps/generic/dl-osinfo.h (_dl_setup_stack_chk_guard): Take

	one parameter.  If non-NULL use it to initialize return value.
	(_dl_setup_pointer_guard): New function.
	* sysdeps/unix/sysv/linux/dl-osinfo.h: Likewise.
	* sysdeps/generic/ldsodefs.h: Declare _dl_random.
	* elf/rtld.c (security_init): Pass _dl_random to
	_dl_setup_stack_chk_guard.  Call _dl_setup_pointer_guard to initialize
	pointer_chk_guard.
	* elf/dl-sysdep.c (_dl_random): New variable.
	(_dl_sysdep_start): Handle AT_RANDOM.
	(_dl_show_auxv): Likewise.
	* elf/dl-support.c (_dl_random): New variable.
	(_dl_aux_init): Handle AT_RANDOM.
	* csu/libc-start.c [!SHARED] (libc_start_main): Pass _dl_random
	to _dl_setup_stack_chk_guard.

	* elf/elf.h (AT_RANDOM): Define AT_BASE_PLATFORM and AT_RANDOM.

1 files changed, 23 insertions, 6 deletions

diff --git a/sysdeps/generic/dl-osinfo.h b/sysdeps/generic/dl-osinfo.h
index 60b84a9..02ec28d 100644
--- a/sysdeps/generic/dl-osinfo.h
+++ b/sysdeps/generic/dl-osinfo.h
@@ -1,12 +1,29 @@
 #include <stdint.h>
 
 static inline uintptr_t __attribute__ ((always_inline))
-_dl_setup_stack_chk_guard (void)
+_dl_setup_stack_chk_guard (void *dl_random)
 {
-  uintptr_t ret = 0;
-  unsigned char *p = (unsigned char *) &ret;
-  p[sizeof (ret) - 1] = 255;
-  p[sizeof (ret) - 2] = '\n';
-  p[0] = 0;
+  uintptr_t ret;
+  if (dl_random == NULL)
+    {
+      ret = 0;
+      unsigned char *p = (unsigned char *) &ret;
+      p[sizeof (ret) - 1] = 255;
+      p[sizeof (ret) - 2] = '\n';
+      p[0] = 0;
+    }
+  else
+    memcmp (&ret, dl_random, sizeof (ret));
+  return ret;
+}
+
+static inline uintptr_t __attribute__ ((always_inline))
+_dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard)
+{
+  uintptr_t ret;
+  if (dl_random == NULL)
+    ret = stack_chk_guard;
+  else
+    memcmp (&ret, (char *) dl_random + sizeof (ret), sizeof (ret));
   return ret;
 }