* Versions.def (ld): Add GLIBC_2.4.

	* configure.in: Add --enable-stackguard-randomization option.
	(ENABLE_STACKGUARD_RANDOMIZE): New define.
	* config.h.in (ENABLE_STACKGUARD_RANDOMIZE): Add.
	* sysdeps/unix/sysv/linux/dl-osinfo.h: Include stdint.h.
	(_dl_setup_stack_chk_guard): New inline function.
	* sysdeps/generic/dl-osinfo.h: Include stdint.h.
	(_dl_setup_stack_chk_guard): New inline function.
	* elf/rtld.c (__stack_chk_guard): New variable.
	(dl_main): Remove all traces of TLS_INIT_TP_EXPENSIVE.
	Set __stack_chk_guard to _dl_setup_stack_chk_guard (),
	use THREAD_SET_STACK_GUARD if defined.
	* elf/Versions (ld): Export __stack_chk_guard@@GLIBC_2.4.
	* sysdeps/generic/libc-start.c (__stack_chk_guard): New variable.
	(__libc_start_main): Set __stack_chk_guard to
	_dl_setup_stack_chk_guard (), use THREAD_SET_STACK_GUARD if defined.
	* sysdeps/generic/libc-tls.c (__libc_setup_tls): Remove all
	traces of TLS_INIT_TP_EXPENSIVE.
	* debug/Versions (libc): Export __stack_chk_fail@@GLIBC_2.4.
	* debug/Makefile (routines): Add stack_chk_fail.
	(static-only-routines): Add stack_chk_fail_local.
	* debug/stack_chk_fail_local.c: New file.
	* debug/stack_chk_fail.c: New file.
	* elf/Makefile: Add rules to build and run tst-stackguard1{,-static}
	tests.
	* elf/tst-stackguard1.c: New file.
	* elf/tst-stackguard1-static.c: New file.
	* elf/stackguard-macros.h: New file.

1 files changed, 22 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/dl-osinfo.h b/sysdeps/unix/sysv/linux/dl-osinfo.h
index 03e1de716c..e374023841 100644
--- a/sysdeps/unix/sysv/linux/dl-osinfo.h
+++ b/sysdeps/unix/sysv/linux/dl-osinfo.h
@@ -23,6 +23,7 @@
 #include <sys/utsname.h>
 #include "kernel-features.h"
 #include <dl-sysdep.h>
+#include <stdint.h>
 
 #ifndef MIN
 # define MIN(a,b) (((a)<(b))?(a):(b))
@@ -157,3 +158,24 @@ _dl_discover_osversion (void)
     else if (__LINUX_KERNEL_VERSION > 0)				      \
       FATAL ("FATAL: cannot determine kernel version\n");		      \
   } while (0)
+
+static inline uintptr_t __attribute__ ((always_inline))
+_dl_setup_stack_chk_guard (void)
+{
+  uintptr_t ret;
+#ifdef ENABLE_STACKGUARD_RANDOMIZE
+  int fd = __open ("/dev/urandom", O_RDONLY);
+  if (fd >= 0)
+    {
+      ssize_t reslen = __read (fd, &ret, sizeof (ret));
+      __close (fd);
+      if (reslen == (ssize_t) sizeof (ret))
+	return ret;
+    }
+#endif
+  ret = 0;
+  unsigned char *p = (unsigned char *) &ret;
+  p[sizeof (ret) - 1] = 255;
+  p[sizeof (ret) - 2] = '\n';
+  return ret;
+}