diff --git a/Create.c b/Create.c
index 0399732..178d62e 100644
--- a/Create.c
+++ b/Create.c
@@ -74,6 +74,8 @@ int Create(struct supertype *st, char *mddev, int mdfd,
 	mdu_array_info_t array;
 	int major = BITMAP_MAJOR_HI;
 
+	memset(array, 0, sizeof(array));
+
 	vers = md_get_version(mdfd);
 	if (vers < 9000) {
 		fprintf(stderr, Name ": Create requires md driver version 0.90.0 or later\n");
diff --git a/super0.c b/super0.c
index 64acf1a..2884855 100644
--- a/super0.c
+++ b/super0.c
@@ -691,7 +691,7 @@ static int add_internal_bitmap0(struct supertype *st, void *sbv, int chunk, int
 
 	sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 
-	memset(bms, sizeof(*bms), 0);
+	memset(bms, 0, sizeof(*bms));
 	bms->magic = __cpu_to_le32(BITMAP_MAGIC);
 	bms->version = __cpu_to_le32(major);
 	uuid_from_super0((int*)bms->uuid, sb);
diff --git a/super1.c b/super1.c
index 75f0c8a..bb98bb9 100644
--- a/super1.c
+++ b/super1.c
@@ -896,7 +896,7 @@ add_internal_bitmap1(struct supertype *st, void *sbv,
 	sb->bitmap_offset = __cpu_to_le32(2);
 
 	sb->feature_map = __cpu_to_le32(__le32_to_cpu(sb->feature_map) | 1);
-	memset(bms, sizeof(*bms), 0);
+	memset(bms, 0, sizeof(*bms));
 	bms->magic = __cpu_to_le32(BITMAP_MAGIC);
 	bms->version = __cpu_to_le32(major);
 	uuid_from_super1((int*)bms->uuid, sb);