From patchwork Mon Apr 24 07:52:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Starke" X-Patchwork-Id: 677102 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 A7863C77B7E for ; Mon, 24 Apr 2023 07:54:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231373AbjDXHym (ORCPT ); Mon, 24 Apr 2023 03:54:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231416AbjDXHyk (ORCPT ); Mon, 24 Apr 2023 03:54:40 -0400 Received: from mta-64-227.siemens.flowmailer.net (mta-64-227.siemens.flowmailer.net [185.136.64.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD90010E5 for ; Mon, 24 Apr 2023 00:54:38 -0700 (PDT) Received: by mta-64-227.siemens.flowmailer.net with ESMTPSA id 20230424075437aa189d47b40358c043 for ; Mon, 24 Apr 2023 09:54:37 +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=RH+IPOwJITsK55x7GggxOQ9MIYHJ4riLL8mEAOOeoXc=; b=SzKskAqAU1VFoE/Uv0dZm+lVtO9JrwPoRL43i05+A47eUJ1Gq2QWJ74nmZhFludD8f0vJL CEvajtupfrgJEa4JHVrFxU9gWTkjSx/r3Yz37kq0Bggso5aUulPBm1Hz0HLMLOx0UlaYshGa PWO4s5g2WPpWsmhEeD6qSkx/Wy/Ss=; From: "D. Starke" To: linux-serial@vger.kernel.org, gregkh@linuxfoundation.org, jirislaby@kernel.org, ilpo.jarvinen@linux.intel.com Cc: linux-kernel@vger.kernel.org, Daniel Starke Subject: [PATCH v3 6/8] tty: n_gsm: increase gsm_mux unsupported counted where appropriate Date: Mon, 24 Apr 2023 09:52:49 +0200 Message-Id: <20230424075251.5216-6-daniel.starke@siemens.com> In-Reply-To: <20230424075251.5216-1-daniel.starke@siemens.com> References: <20230424075251.5216-1-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 The structure gsm_mux contains the 'unsupported' field. However, there is currently no place in the code which increases this counter. Increase the 'unsupported' statistics counter in the following case: - an unsupported frame type has been requested by the peer via parameter negotiation - a control frame with an unsupported but known command has been received Note that we have no means to detect an inconsistent/unsupported adaptation sufficient accuracy as this changes the structure of the UI/UIH frames. E.g. a one byte header is added in case of convergence layer type 2 instead of 1 and contains the modem signal octet with the state of the signal lines. There is no checksum or other value which indicates of this field is correct or should be present. Therefore, we can only assume protocol correctness here. See also 'gsm_dlci_data()' where this is handled. Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 3 +++ 1 file changed, 3 insertions(+) v2 -> v3: No changes. Link: https://lore.kernel.org/all/20230420085017.7314-7-daniel.starke@siemens.com/ diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 10fc02133efa..941489230f9f 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -1590,6 +1590,7 @@ static int gsm_process_negotiation(struct gsm_mux *gsm, unsigned int addr, if (debug & DBG_ERRORS) pr_info("%s unsupported I frame request in PN\n", __func__); + gsm->unsupported++; return -EINVAL; default: if (debug & DBG_ERRORS) @@ -1897,6 +1898,8 @@ static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, /* Optional unsupported commands */ case CMD_RPN: /* Remote port negotiation */ case CMD_SNC: /* Service negotiation command */ + gsm->unsupported++; + fallthrough; default: /* Reply to bad commands with an NSC */ buf[0] = command;