commit fe9d0ed6cb10d5403e54d2dd12628a0ec345ae6e
author Josh Gao <jmgao@google.com> Wed Oct 07 14:32:36 2015 -0700
committer Josh Gao <jmgao@google.com> Fri Oct 09 15:59:04 2015 -0700
tree 6d2041d7c21174599ed9815d43f43b82568ffebd
parent 93c0f5ee00d1357247fda333c9d49c8673c9c83b

Move setjmp cookie to a shared globals struct.

Change-Id: I59a4c187d61524c4e48655c4c6376dba0d41eee2

libc/bionic/libc_init_common.cpp

diff --git a/libc/bionic/libc_init_common.cpp b/libc/bionic/libc_init_common.cpp
index 5b9edaf..4995414 100644
--- a/libc/bionic/libc_init_common.cpp
+++ b/libc/bionic/libc_init_common.cpp
@@ -51,7 +51,6 @@
 #include "pthread_internal.h"
 
 extern "C" abort_msg_t** __abort_message_ptr;
-extern "C" void __bionic_setjmp_cookie_init(void);
 extern "C" int __system_properties_init(void);
 extern "C" int __set_tls(void* ptr);
 extern "C" int __set_tid_address(int* tid_address);
@@ -114,6 +113,7 @@
   __libc_globals.initialize();
   __libc_globals.mutate([&args](libc_globals* globals) {
     __libc_init_vdso(globals, args);
+    __libc_init_setjmp_cookie(globals, args);
   });
 }
 
@@ -133,7 +133,6 @@
   __pthread_internal_add(main_thread);
 
   __system_properties_init(); // Requires 'environ'.
-  __bionic_setjmp_cookie_init();
 }
 
 __noreturn static void __early_abort(int line) {

libc/bionic/setjmp_cookie.cpp

diff --git a/libc/bionic/setjmp_cookie.cpp b/libc/bionic/setjmp_cookie.cpp
index cf79e83..ce57fd1 100644
--- a/libc/bionic/setjmp_cookie.cpp
+++ b/libc/bionic/setjmp_cookie.cpp
@@ -34,30 +34,30 @@
 #include <sys/auxv.h>
 #include <sys/cdefs.h>
 
+#include "private/bionic_globals.h"
 #include "private/libc_logging.h"
+#include "private/KernelArgumentBlock.h"
 
-extern "C" __LIBC_HIDDEN__ int getentropy(void*, size_t);
-static long __bionic_setjmp_cookie;
-
-extern "C" void __bionic_setjmp_cookie_init() {
-  char* random_data = reinterpret_cast<char*>(getauxval(AT_RANDOM));
+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);
 
   // Mask off the last bit to store the signal flag.
-  __bionic_setjmp_cookie = value & ~1;
+  globals->setjmp_cookie = value & ~1;
 }
 
-extern "C" long __bionic_setjmp_cookie_get(long sigflag) {
+extern "C" __LIBC_HIDDEN__ long __bionic_setjmp_cookie_get(long sigflag) {
   if (sigflag & ~1) {
     __libc_fatal("unexpected sigflag value: %ld", sigflag);
   }
 
-  return __bionic_setjmp_cookie | sigflag;
+  return __libc_globals->setjmp_cookie | sigflag;
 }
 
 // Aborts if cookie doesn't match, returns the signal flag otherwise.
-extern "C" long __bionic_setjmp_cookie_check(long cookie) {
-  if (__bionic_setjmp_cookie != (cookie & ~1)) {
+extern "C" __LIBC_HIDDEN__ long __bionic_setjmp_cookie_check(long cookie) {
+  if (__libc_globals->setjmp_cookie != (cookie & ~1)) {
     __libc_fatal("setjmp cookie mismatch");
   }
 

libc/private/bionic_globals.h

diff --git a/libc/private/bionic_globals.h b/libc/private/bionic_globals.h
index 788a759..644b5a4 100644
--- a/libc/private/bionic_globals.h
+++ b/libc/private/bionic_globals.h
@@ -34,6 +34,7 @@
 
 struct libc_globals {
   vdso_entry vdso[VDSO_END];
+  long setjmp_cookie;
 };
 
 __LIBC_HIDDEN__ extern WriteProtected<libc_globals> __libc_globals;
@@ -41,5 +42,7 @@
 class KernelArgumentBlock;
 __LIBC_HIDDEN__ void __libc_init_vdso(libc_globals* globals,
                                       KernelArgumentBlock& args);
+__LIBC_HIDDEN__ void __libc_init_setjmp_cookie(libc_globals* globals,
+                                               KernelArgumentBlock& args);
 
 #endif