diff --git a/extent_io.c b/extent_io.c
index 70fecbbf..8f0a8763 100644
--- a/extent_io.c
+++ b/extent_io.c
@@ -568,6 +568,7 @@ static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
 		BUG();
 		return NULL;
 	}
+	memset(eb, 0, sizeof(struct extent_buffer) + blocksize);
 
 	eb->start = bytenr;
 	eb->len = blocksize;
diff --git a/mkfs.c b/mkfs.c
index 5e483dcf..428ec18f 100644
--- a/mkfs.c
+++ b/mkfs.c
@@ -411,6 +411,13 @@ static int fill_inode_item(struct btrfs_trans_handle *trans,
 	u64 blocks = 0;
 	u64 sectorsize = root->sectorsize;
 
+	/*
+	 * btrfs_inode_item has some reserved fields
+	 * and represents on-disk inode entry, so
+	 * zero everything to prevent information leak
+	 */
+	memset(dst, 0, sizeof (*dst));
+
 	btrfs_set_stack_inode_generation(dst, trans->transid);
 	btrfs_set_stack_inode_size(dst, src->st_size);
 	btrfs_set_stack_inode_nbytes(dst, 0);