From patchwork Mon Apr 24 07:52:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Starke" X-Patchwork-Id: 677100 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 DF4F0C77B76 for ; Mon, 24 Apr 2023 07:56:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230205AbjDXH4V (ORCPT ); Mon, 24 Apr 2023 03:56:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231223AbjDXH4T (ORCPT ); Mon, 24 Apr 2023 03:56:19 -0400 X-Greylist: delayed 78 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 24 Apr 2023 00:55:56 PDT Received: from mta-65-226.siemens.flowmailer.net (mta-65-226.siemens.flowmailer.net [185.136.65.226]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18F962133 for ; Mon, 24 Apr 2023 00:55:55 -0700 (PDT) Received: by mta-65-226.siemens.flowmailer.net with ESMTPSA id 20230424075435b0546cd02705b001ff for ; Mon, 24 Apr 2023 09:54:36 +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=ULLYgmbG/ykB1RRdK7/F/RuI/3VzvVuXKuXWTjBDDSs=; b=J5DfR/zRamnMR2A/mdk89g4pEaRG1IP+wLnRwMuVMv24OT2IBtHlltQ/FEW9HL4Hp238qs BuZyf/OhbT+b5S6GkZ89IuDCths74oqPh1aG8RHTTkaVAeJiWlppk9w9EcPK5h+b8/9s3cj3 QvaweLxZDH9Pv8dsVIMoM5+XNar+A=; 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 4/8] tty: n_gsm: add open_error counter to gsm_mux Date: Mon, 24 Apr 2023 09:52:47 +0200 Message-Id: <20230424075251.5216-4-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 Extend the n_gsm link statistics by a failed link open counter in preparation for an upcoming patch which will expose these. This counter is increased whenever an attempt to open the control channel failed. This is true in the following cases: - new DLCI allocation failed - connection request (SAMB) with invalid CR flag has been received - connection response (UA) timed out - parameter negotiation timed out or failed Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) v2 -> v3: Merged commit 2b3174c96696 ("n_gsm: Use array_index_nospec() with index that comes from userspace") No other changes. Link: https://lore.kernel.org/all/20230420085017.7314-5-daniel.starke@siemens.com/ diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 9a2cf3e14678..6b6fafb1098a 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -339,6 +339,7 @@ struct gsm_mux { unsigned long bad_fcs; unsigned long malformed; unsigned long io_error; + unsigned long open_error; unsigned long bad_size; unsigned long unsupported; }; @@ -1730,25 +1731,32 @@ static void gsm_control_negotiation(struct gsm_mux *gsm, unsigned int cr, struct gsm_dlci *dlci; struct gsm_dlci_param_bits *params; - if (dlen < sizeof(struct gsm_dlci_param_bits)) + if (dlen < sizeof(struct gsm_dlci_param_bits)) { + gsm->open_error++; return; + } /* Invalid DLCI? */ params = (struct gsm_dlci_param_bits *)data; addr = FIELD_GET(PN_D_FIELD_DLCI, params->d_bits); - if (addr == 0 || addr >= NUM_DLCI || !gsm->dlci[addr]) + if (addr == 0 || addr >= NUM_DLCI || !gsm->dlci[addr]) { + gsm->open_error++; return; + } dlci = gsm->dlci[addr]; /* Too late for parameter negotiation? */ - if ((!cr && dlci->state == DLCI_OPENING) || dlci->state == DLCI_OPEN) + if ((!cr && dlci->state == DLCI_OPENING) || dlci->state == DLCI_OPEN) { + gsm->open_error++; return; + } /* Process the received parameters */ if (gsm_process_negotiation(gsm, addr, cr, params) != 0) { /* Negotiation failed. Close the link. */ if (debug & DBG_ERRORS) pr_info("%s PN failed\n", __func__); + gsm->open_error++; gsm_dlci_close(dlci); return; } @@ -1768,6 +1776,7 @@ static void gsm_control_negotiation(struct gsm_mux *gsm, unsigned int cr, } else { if (debug & DBG_ERRORS) pr_info("%s PN in invalid state\n", __func__); + gsm->open_error++; } } @@ -2221,6 +2230,7 @@ static void gsm_dlci_t1(struct timer_list *t) dlci->retries--; mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); } else { + gsm->open_error++; gsm_dlci_begin_close(dlci); /* prevent half open link */ } break; @@ -2236,6 +2246,7 @@ static void gsm_dlci_t1(struct timer_list *t) dlci->mode = DLCI_MODE_ADM; gsm_dlci_open(dlci); } else { + gsm->open_error++; gsm_dlci_begin_close(dlci); /* prevent half open link */ } @@ -2757,12 +2768,16 @@ static void gsm_queue(struct gsm_mux *gsm) switch (gsm->control) { case SABM|PF: - if (cr == 1) + if (cr == 1) { + gsm->open_error++; goto invalid; + } if (dlci == NULL) dlci = gsm_dlci_alloc(gsm, address); - if (dlci == NULL) + if (dlci == NULL) { + gsm->open_error++; return; + } if (dlci->dead) gsm_response(gsm, address, DM|PF); else {