1 files changed, 8 insertions, 5 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 2ec8eb5..8c05e5b 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1814,11 +1814,14 @@ static int expand_downwards(struct vm_area_struct *vma,
 		size = vma->vm_end - address;
 		grow = (vma->vm_start - address) >> PAGE_SHIFT;
 
-		error = acct_stack_growth(vma, size, grow);
-		if (!error) {
-			vma->vm_start = address;
-			vma->vm_pgoff -= grow;
-			perf_event_mmap(vma);
+		error = -ENOMEM;
+		if (grow <= vma->vm_pgoff) {
+			error = acct_stack_growth(vma, size, grow);
+			if (!error) {
+				vma->vm_start = address;
+				vma->vm_pgoff -= grow;
+				perf_event_mmap(vma);
+			}
 		}
 	}
 	vma_unlock_anon_vma(vma);