x86: Increase MIN_GAP to include randomized stack

[pandora-kernel.git] / arch / x86 / mm / mmap.c

diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 1658296..c8191de 100644 (file)
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -29,13 +29,26 @@
 #include <linux/random.h>
 #include <linux/limits.h>
 #include <linux/sched.h>
+#include <asm/elf.h>
+
+static unsigned int stack_maxrandom_size(void)
+{
+       unsigned int max = 0;
+       if ((current->flags & PF_RANDOMIZE) &&
+               !(current->personality & ADDR_NO_RANDOMIZE)) {
+               max = ((-1U) & STACK_RND_MASK) << PAGE_SHIFT;
+       }
+
+       return max;
+}
+
 
 /*
  * Top of mmap area (just below the process stack).
  *
- * Leave an at least ~128 MB hole.
+ * Leave an at least ~128 MB hole with possible stack randomization.
  */
-#define MIN_GAP (128*1024*1024)
+#define MIN_GAP (128*1024*1024UL + stack_maxrandom_size())
 #define MAX_GAP (TASK_SIZE/6*5)
 
 /*