diff --git a/tap.c b/tap.c
index f8314ef..11ac732 100644
--- a/tap.c
+++ b/tap.c
@@ -747,14 +747,26 @@ redo:
 		return -ECONNRESET;
 	}
 
-	while (n > (ssize_t)sizeof(uint32_t)) {
-		ssize_t len = ntohl(*(uint32_t *)p);
+	while (n > 0) {
+		ssize_t len;
+
+		/* Force receiving at least a complete length descriptor to
+		 * avoid an inconsistent stream.
+		 */
+		if (n < (ssize_t)sizeof(uint32_t)) {
+			rem = recv(c->fd_tap, p + n,
+				   (ssize_t)sizeof(uint32_t) - n, 0);
+			if ((n += rem) != (ssize_t)sizeof(uint32_t))
+				return 0;
+		}
+
+		len = ntohl(*(uint32_t *)p);
 
 		p += sizeof(uint32_t);
 		n -= sizeof(uint32_t);
 
 		/* At most one packet might not fit in a single read, and this
-		 * needs to be blocking.
+		 * also needs to be blocking.
 		 */
 		if (len > n) {
 			rem = recv(c->fd_tap, p + n, len - n, 0);