diff --git a/src/proto_htx.c b/src/proto_htx.c
index 3232d0a..c613e72 100644
--- a/src/proto_htx.c
+++ b/src/proto_htx.c
@@ -1245,10 +1245,8 @@
 		 * right length is then restored. We must do that, because when an HTX
 		 * message is stored into a buffer, it appears as full.
 		 */
-		b_set_data(&req->buf, co_data(req));
-		if (msg->flags & HTTP_MSGF_XFER_LEN)
-			htx->extra -= channel_forward(req, htx->extra);
-		b_set_data(&req->buf, b_size(&req->buf));
+		if ((msg->flags & HTTP_MSGF_XFER_LEN) && htx->extra)
+			htx->extra -= channel_htx_forward(req, htx, htx->extra);
 	}
 
 	/* Check if the end-of-message is reached and if so, switch the message
@@ -2185,10 +2183,8 @@
 		 * right length is then restored. We must do that, because when an HTX
 		 * message is stored into a buffer, it appears as full.
 		 */
-		b_set_data(&res->buf, co_data(res));
-		if (msg->flags & HTTP_MSGF_XFER_LEN)
-			htx->extra -= channel_forward(res, htx->extra);
-		b_set_data(&res->buf, b_size(&res->buf));
+		if ((msg->flags & HTTP_MSGF_XFER_LEN) && htx->extra)
+			htx->extra -= channel_htx_forward(res, htx, htx->extra);
 	}
 
 	if (!(msg->flags & HTTP_MSGF_XFER_LEN)) {