Revert "Revert "Attempt to use arc4random where getauxval(AT_RANDOM) is used.""
This reverts commit 60d052dda600f26fdb6180ac1a2c53e97df5a58a.
Bug: http://b/27729263
Change-Id: I7f32dc9f9a1f21fda3213f10da940821e1bdd63f
diff --git a/libc/bionic/setjmp_cookie.cpp b/libc/bionic/setjmp_cookie.cpp
index 3be675a..4fa68c2 100644
--- a/libc/bionic/setjmp_cookie.cpp
+++ b/libc/bionic/setjmp_cookie.cpp
@@ -34,14 +34,14 @@
#include <sys/auxv.h>
#include <sys/cdefs.h>
+#include "private/bionic_arc4random.h"
#include "private/bionic_globals.h"
#include "private/libc_logging.h"
#include "private/KernelArgumentBlock.h"
-void __libc_init_setjmp_cookie(libc_globals* globals,
- KernelArgumentBlock& args) {
- char* random_data = reinterpret_cast<char*>(args.getauxval(AT_RANDOM));
- long value = *reinterpret_cast<long*>(random_data + 8);
+void __libc_init_setjmp_cookie(libc_globals* globals, KernelArgumentBlock& args) {
+ long value;
+ __libc_safe_arc4random_buf(&value, sizeof(value), args);
// Mask off the last bit to store the signal flag.
globals->setjmp_cookie = value & ~1;