diff --git a/mm/mlock.c b/mm/mlock.c
index 4077b1e8e199d8694fb014e4eede3fd42c4ad6a9..d9040aea2be00dfcba3e537ed939ccc73774ce1d 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -597,8 +597,6 @@ 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;
@@ -682,7 +680,13 @@ 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)));
+	if (!len)
+		return -EINVAL;
+
 	start &= PAGE_MASK;
 
 	lock_limit = rlimit(RLIMIT_MEMLOCK);
@@ -740,8 +744,13 @@ SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len)
 {
 	int ret;
 
+	if (!len)
+		return 0;
+
 	len = PAGE_ALIGN(len + (offset_in_page(start)));
 	start &= PAGE_MASK;
+	if (!len)
+		return -EINVAL;
 
 	if (down_write_killable(&current->mm->mmap_sem))
 		return -EINTR;