diff --git a/blobmsg.c b/blobmsg.c
index cc6b2f3..bddf2c8 100644
--- a/blobmsg.c
+++ b/blobmsg.c
@@ -26,7 +26,7 @@ bool blobmsg_check_attr(const struct blob_attr *attr, bool name)
 	if (!hdr->namelen && name)
 		return false;
 
-	if (hdr->namelen > blob_len(attr))
+	if (hdr->namelen > blob_len(attr) - sizeof(struct blobmsg_hdr))
 		return false;
 
 	if (hdr->name[hdr->namelen] != 0)