diff --git a/[refs] b/[refs]
index ff5477ca687b..b690c906cf24 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7808a4c4853fa0203085cf2217e01823d9f0c70c
+refs/heads/master: f37ac5a144027cddfcf1dfab30eb7c2ba765f5ca
diff --git a/trunk/drivers/tty/n_gsm.c b/trunk/drivers/tty/n_gsm.c
index da3b31a98654..14c26cdd8aca 100644
--- a/trunk/drivers/tty/n_gsm.c
+++ b/trunk/drivers/tty/n_gsm.c
@@ -833,8 +833,7 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
 		break;
 	case 2:	/* Unstructed with modem bits. Always one byte as we never
 		   send inline break data */
-		*dp += gsm_encode_modem(dlci);
-		len--;
+		*dp++ = gsm_encode_modem(dlci);
 		break;
 	}
 	WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len);