Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933633AbcKILHR (ORCPT ); Wed, 9 Nov 2016 06:07:17 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:54486 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932467AbcKILHL (ORCPT ); Wed, 9 Nov 2016 06:07:11 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [PATCH 4.8 052/138] USB: serial: cp210x: fix tiocmget error handling Date: Wed, 9 Nov 2016 11:45:35 +0100 Message-Id: <20161109102847.134321562@linuxfoundation.org> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161109102844.808685475@linuxfoundation.org> References: <20161109102844.808685475@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1047 Lines: 34 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit de24e0a108bc48062e1c7acaa97014bce32a919f upstream. The current tiocmget implementation would fail to report errors up the stack and instead leaked a few bits from the stack as a mask of modem-status flags. Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control") Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/cp210x.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -1077,7 +1077,9 @@ static int cp210x_tiocmget(struct tty_st u8 control; int result; - cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control); + result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control); + if (result) + return result; result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0) |((control & CONTROL_RTS) ? TIOCM_RTS : 0)