diff --git a/kernel/fork.c b/kernel/fork.c
index 5b13eea2e75721c5cfae3a0818bb806e40e73a54..017fb23d5983dc8eca06220ae9d81e9e37e0a4b9 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -386,7 +386,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 		}
 		charge = 0;
 		if (mpnt->vm_flags & VM_ACCOUNT) {
-			unsigned int len = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
+			unsigned long len;
+			len = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
 			if (security_vm_enough_memory_mm(oldmm, len)) /* sic */
 				goto fail_nomem;
 			charge = len;