From mboxrd@z Thu Jan 1 00:00:00 1970 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 A9AF7CCA480 for ; Thu, 7 Jul 2022 11:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235408AbiGGLd4 (ORCPT ); Thu, 7 Jul 2022 07:33:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235327AbiGGLdy (ORCPT ); Thu, 7 Jul 2022 07:33:54 -0400 Received: from mta-65-225.siemens.flowmailer.net (mta-65-225.siemens.flowmailer.net [185.136.65.225]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B56922A708 for ; Thu, 7 Jul 2022 04:33:50 -0700 (PDT) Received: by mta-65-225.siemens.flowmailer.net with ESMTPSA id 20220707113347b436a0426659325429 for ; Thu, 07 Jul 2022 13:33:48 +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; bh=4zrox7ZlHscR7GaMrL4oS4/tk+1RCzBT6lJQ3JfJL0o=; b=HUiTBM6BLE6FL/IKNjsboP7hCLX6YfsV25sCaqNvdbwN9jig4jMsRx9/uwSTllrWuoV43E 9GKrXZbk+hxwly5vX37zBkkvykw6ywSzvzTvTJyG7O2RLNkKWEZMal1sxbYQN6SW61zW5FkZ vghSkA6GzHoyVr16NOIQH9xf+uCZY=; 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 v2 1/4] tty: n_gsm: fix wrong T1 retry count handling Date: Thu, 7 Jul 2022 13:32:20 +0200 Message-Id: <20220707113223.3685-1-daniel.starke@siemens.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-314044:519-21489:flowmailer Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 5.7.3 states that the valid range for the maximum number of retransmissions (N2) is from 0 to 255 (both including). gsm_dlci_t1() handles this number incorrectly by performing N2 - 1 retransmission attempts. Setting N2 to zero results in more than 255 retransmission attempts. Fix gsm_dlci_t1() to comply with 3GPP 27.010. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) No changes have been applied compared to v1. diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index ba399a660573..1a70e7ae90cc 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -1805,8 +1805,8 @@ static void gsm_dlci_t1(struct timer_list *t) switch (dlci->state) { case DLCI_OPENING: - dlci->retries--; if (dlci->retries) { + dlci->retries--; gsm_command(dlci->gsm, dlci->addr, SABM|PF); mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); } else if (!dlci->addr && gsm->control == (DM | PF)) { @@ -1821,8 +1821,8 @@ static void gsm_dlci_t1(struct timer_list *t) break; case DLCI_CLOSING: - dlci->retries--; if (dlci->retries) { + dlci->retries--; gsm_command(dlci->gsm, dlci->addr, DISC|PF); mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); } else -- 2.34.1