diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index a25c9763fce1..d6e46dd1350b 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -389,7 +389,7 @@ static noinline void __init kasan_stack_oob(void)
 static noinline void __init ksize_unpoisons_memory(void)
 {
 	char *ptr;
-	size_t size = 123, real_size = size;
+	size_t size = 123, real_size;
 
 	pr_info("ksize() unpoisons the whole allocated chunk\n");
 	ptr = kmalloc(size, GFP_KERNEL);