From patchwork Thu Apr 14 09:42:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Starke" X-Patchwork-Id: 561404 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77D76C433FE for ; Thu, 14 Apr 2022 09:46:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241937AbiDNJso (ORCPT ); Thu, 14 Apr 2022 05:48:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241971AbiDNJqn (ORCPT ); Thu, 14 Apr 2022 05:46:43 -0400 X-Greylist: delayed 62 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 14 Apr 2022 02:44:01 PDT Received: from mta-64-226.siemens.flowmailer.net (mta-64-226.siemens.flowmailer.net [185.136.64.226]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7CDD70928 for ; Thu, 14 Apr 2022 02:44:01 -0700 (PDT) Received: by mta-64-226.siemens.flowmailer.net with ESMTPSA id 202204140942525a26cdd311193ec211 for ; Thu, 14 Apr 2022 11:42:58 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm1; d=siemens.com; i=daniel.starke@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc:References:In-Reply-To; bh=qo+J4Lih8268JeqdwObz7YR4B/SLCefExJgGvrS1nSY=; b=jsHEiAIF2Jf6ldjL7SBTyTHT55mj4nYgv6c0+epwdy+uBGwb9KUizKzVG1KGiSJZZcx2q7 uemSzfZw7idF4wiY2HiQgt2xYGgtcPtXPdzhuxi1/ei02mxHSQFJOk9RTEDjw/Dtbc91SCQ3 9HqZDdg/aeWd/BrYVXjGyfEooWstE=; From: "D. Starke" To: linux-serial@vger.kernel.org, gregkh@linuxfoundation.org, jirislaby@kernel.org Cc: linux-kernel@vger.kernel.org, Daniel Starke Subject: [PATCH 18/20] tty: n_gsm: fix implicit CR bit encoding in address field Date: Thu, 14 Apr 2022 02:42:23 -0700 Message-Id: <20220414094225.4527-18-daniel.starke@siemens.com> In-Reply-To: <20220414094225.4527-1-daniel.starke@siemens.com> References: <20220414094225.4527-1-daniel.starke@siemens.com> MIME-Version: 1.0 X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-314044:519-21489:flowmailer Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org From: Daniel Starke n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010. See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516 The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to the newer 27.010 here. Chapter 5.2.1.2 describes the encoding of the address field within the frame header. It is made up of the DLCI address, command/response (CR) bit and EA bit. Use the predefined CR value instead of a plain 2 in alignment to the remaining code and to make the encoding obvious. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Cc: stable@vger.kernel.org Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 1e135a71860f..ecd2ecc61b14 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -754,7 +754,7 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) *--dp = msg->ctrl; if (gsm->initiator) - *--dp = (msg->addr << 2) | 2 | EA; + *--dp = (msg->addr << 2) | CR | EA; else *--dp = (msg->addr << 2) | EA; *fcs = gsm_fcs_add_block(INIT_FCS, dp , msg->data - dp);