From patchwork Fri Mar 20 16:29:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre-Louis Bossart X-Patchwork-Id: 193220 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC996C4332D for ; Fri, 20 Mar 2020 16:32:46 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3BCD62076F for ; Fri, 20 Mar 2020 16:32:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="dYg+U42p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3BCD62076F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 74A681661; Fri, 20 Mar 2020 17:31:54 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 74A681661 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1584721964; bh=Gis6zY4C8uv3xVtNtKl6kDO7e2F5qms6Zu4jeY818wU=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=dYg+U42pV+kTsuIyCkpE7tnOve2HeQ80JW79Qi+5gNzBQOwfgmQwjGww857/xvEtZ l2SkzhIt85f9M0XdXbtiCO8tR0TJQk8PKv9bFJlYhHV46N0/Zt9DhUnFGILlr0USlL FiLgHStTDDcC/+C7uu6V/GLgIE8Y9BKZFSyXeWjM= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id A8E04F8028E; Fri, 20 Mar 2020 17:30:22 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 2AA04F80256; Fri, 20 Mar 2020 17:30:15 +0100 (CET) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id B2825F8015B for ; Fri, 20 Mar 2020 17:30:07 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz B2825F8015B IronPort-SDR: lxeEjVA2dV77DJBUaIMmEONbgfWPY51LG+9Rt4RbRgx6YZmeo1+4MRKyRBPRL/PEBnaPIMl3dQ 3jgr9//mAxEQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Mar 2020 09:30:05 -0700 IronPort-SDR: bHWPirFfuFYtgMU59MmbNvzP61dZoKTzksjLxclgAiV7iNaeKV4yNZ16ocT2TZz07y/C009pf4 p/Jot+7gEqLg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,285,1580803200"; d="scan'208";a="248930916" Received: from manallet-mobl.amr.corp.intel.com (HELO pbossart-mobl3.amr.corp.intel.com) ([10.255.34.12]) by orsmga006.jf.intel.com with ESMTP; 20 Mar 2020 09:30:02 -0700 From: Pierre-Louis Bossart To: alsa-devel@alsa-project.org Subject: [PATCH 2/5] soundwire: bus_type: protect cases where no driver name is provided Date: Fri, 20 Mar 2020 11:29:44 -0500 Message-Id: <20200320162947.17663-3-pierre-louis.bossart@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200320162947.17663-1-pierre-louis.bossart@linux.intel.com> References: <20200320162947.17663-1-pierre-louis.bossart@linux.intel.com> MIME-Version: 1.0 Cc: Pierre-Louis Bossart , tiwai@suse.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, Ranjani Sridharan , Hui Wang , vkoul@kernel.org, broonie@kernel.org, srinivas.kandagatla@linaro.org, jank@cadence.com, slawomir.blauciak@intel.com, Sanyog Kale , Bard liao , Rander Wang X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" When the implementation only creates a sdw_master_device and does not provide a master_name, we have a risk of kernel oopses with dereferences of a NULL pointer. Protect with explicit tests. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/bus_type.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index 09a25075e770..c01d74c709d5 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -48,12 +48,14 @@ static int sdw_bus_match(struct device *dev, struct device_driver *ddrv) md = dev_to_sdw_master_device(dev); mdrv = drv_to_sdw_master_driver(ddrv); - /* - * we don't have any hardware information so - * match with a hopefully unique string - */ - ret = !strncmp(md->master_name, mdrv->driver.name, - strlen(md->master_name)); + if (md->master_name) { + /* + * we don't have any hardware information so + * match with a hopefully unique string + */ + ret = !strncmp(md->master_name, mdrv->driver.name, + strlen(md->master_name)); + } } return ret; } @@ -71,9 +73,11 @@ static int sdw_master_modalias(const struct sdw_master_device *md, char *buf, size_t size) { /* modalias is sdw: since we don't have any hardware info */ - - return snprintf(buf, size, "sdw:%s\n", - md->master_name); + if (md->master_name) + return snprintf(buf, size, "sdw:%s\n", + md->master_name); + else + return snprintf(buf, size, "sdw:no_master_driver\n"); } static int sdw_uevent(struct device *dev, struct kobj_uevent_env *env)