diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 09c586474511..1c5c5ea304d3 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -473,7 +473,7 @@ static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
 {
 	unsigned long redzone_start;
 	unsigned long redzone_end;
-	u8 tag;
+	u8 tag = 0xff;
 
 	if (gfpflags_allow_blocking(flags))
 		quarantine_reduce();