diff --git a/src/mux_fcgi.c b/src/mux_fcgi.c
index 5025163..8b3fc31 100644
--- a/src/mux_fcgi.c
+++ b/src/mux_fcgi.c
@@ -2455,7 +2455,7 @@
 		goto fail; // incomplete record
 
 	chunk_reset(&trash);
-	ret = b_xfer(&trash, dbuf, MIN(b_room(&trash), fconn->drl));
+	ret = b_force_xfer(&trash, dbuf, MIN(b_room(&trash), fconn->drl));
 	if (!ret)
 		goto fail;
 	fconn->drl -= ret;