3 files changed, 31 insertions, 2 deletions

diff --git a/include/linux/magic.h b/include/linux/magic.h
index 439f6f3cb0c4..561a5ff92c88 100644
--- a/include/linux/magic.h
+++ b/include/linux/magic.h
@@ -47,4 +47,5 @@
 #define FUTEXFS_SUPER_MAGIC     0xBAD1DEA
 #define INOTIFYFS_SUPER_MAGIC   0x2BAD1DEA
 
+#define STACK_END_MAGIC         0x57AC6E9D
 #endif /* __LINUX_MAGIC_H__ */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4cae9b81a1f8..a85b0cec7d12 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1157,10 +1157,9 @@ struct task_struct {
         pid_t pid;
         pid_t tgid;
 
-#ifdef CONFIG_CC_STACKPROTECTOR
         /* Canary value for the -fstack-protector gcc feature */
         unsigned long stack_canary;
-#endif
+
         /* 
          * pointers to (original) parent process, youngest child, younger sibling,
          * older sibling, respectively.  (p->father can be replaced with 
@@ -2066,6 +2065,19 @@ static inline int object_is_on_stack(void *obj)
 
 extern void thread_info_cache_init(void);
 
+#ifdef CONFIG_DEBUG_STACK_USAGE
+static inline unsigned long stack_not_used(struct task_struct *p)
+{
+        unsigned long *n = end_of_stack(p);
+
+        do {    /* Skip over canary */
+                n++;
+        } while (!*n);
+
+        return (unsigned long)n - (unsigned long)end_of_stack(p);
+}
+#endif
+
 /* set thread flags in other task's structures
  * - see asm/thread_info.h for TIF_xxxx flags available
  */
diff --git a/include/linux/stackprotector.h b/include/linux/stackprotector.h
new file mode 100644
index 000000000000..6f3e54c704c0
--- /dev/null
+++ b/include/linux/stackprotector.h
@@ -0,0 +1,16 @@
+#ifndef _LINUX_STACKPROTECTOR_H
+#define _LINUX_STACKPROTECTOR_H 1
+
+#include <linux/compiler.h>
+#include <linux/sched.h>
+#include <linux/random.h>
+
+#ifdef CONFIG_CC_STACKPROTECTOR
+# include <asm/stackprotector.h>
+#else
+static inline void boot_init_stack_canary(void)
+{
+}
+#endif
+
+#endif