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Diffstat (limited to 'arch/arm/mm/mmap.c')
-rw-r--r--arch/arm/mm/mmap.c14
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index f866870db749..bff3d00bda5b 100644
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -18,8 +18,9 @@
(((pgoff)<<PAGE_SHIFT) & (SHMLBA-1)))
/* gap between mmap and stack */
-#define MIN_GAP (128*1024*1024UL)
-#define MAX_GAP ((TASK_SIZE)/6*5)
+#define MIN_GAP (128*1024*1024UL)
+#define MAX_GAP ((TASK_SIZE)/6*5)
+#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12))
static int mmap_is_legacy(struct rlimit *rlim_stack)
{
@@ -35,6 +36,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack)
static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack)
{
unsigned long gap = rlim_stack->rlim_cur;
+ unsigned long pad = stack_guard_gap;
+
+ /* Account for stack randomization if necessary */
+ if (current->flags & PF_RANDOMIZE)
+ pad += (STACK_RND_MASK << PAGE_SHIFT);
+
+ /* Values close to RLIM_INFINITY can overflow. */
+ if (gap + pad > gap)
+ gap += pad;
if (gap < MIN_GAP)
gap = MIN_GAP;