Ohh man, I should be too old to make this kind of mistake.

Fortunately there is a backstop, so worst case a request would
just fail.

Spotted by: Erik
Missed by: phk, twice

bin/varnishd/cache_center.c

@@ -655,7 +655,7 @@ cnt_fetch(struct sess *sp)
 	 * Space for producing a Content-Length: header including padding
 	 * A billion gigabytes is enough for anybody.
 	 */
-	l += strlen("Content-Length: XxxXxxXxxXxxXxxXxx" + sizeof(void *));
+	l += strlen("Content-Length: XxxXxxXxxXxxXxxXxx") + sizeof(void *);
 
 	if (sp->wrk->ttl < sp->t_req + params->shortlived ||
 	    sp->objcore == NULL)