diff --git a/mm/mlock.c b/mm/mlock.c
index 55b3b3672977be1e3841c07e2b55b3cfc12709b0..4e47dd274b91a8747f3b13bd0fe9837d188ff1ba 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -568,8 +568,6 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
 	end = start + len;
 	if (end < start)
 		return -EINVAL;
-	if (end == start)
-		return 0;
 	vma = find_vma(current->mm, start);
 	if (!vma || vma->vm_start > start)
 		return -ENOMEM;
@@ -655,9 +653,15 @@ static __must_check int do_mlock(unsigned long start, size_t len, vm_flags_t fla
 	if (!can_do_mlock())
 		return -EPERM;
 
+	if (!len)
+		return 0;
+
 	len = PAGE_ALIGN(len + (offset_in_page(start)));
 	start &= PAGE_MASK;
 
+	if (!len)
+		return -EINVAL;
+
 	lock_limit = rlimit(RLIMIT_MEMLOCK);
 	lock_limit >>= PAGE_SHIFT;
 	locked = len >> PAGE_SHIFT;
@@ -715,8 +719,13 @@ SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len)
 
 	start = untagged_addr(start);
 
+	if (!len)
+		return 0;
+
 	len = PAGE_ALIGN(len + (offset_in_page(start)));
 	start &= PAGE_MASK;
+	if (!len)
+		return -EINVAL;
 
 	if (mmap_write_lock_killable(current->mm))
 		return -EINTR;