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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 2FCE6C10F0E for ; Thu, 18 Apr 2019 18:31:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F31D32064A for ; Thu, 18 Apr 2019 18:31:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555612305; bh=9dYun8rVuXmR92OQcnQbnMiLZwOPW92CXr+aDxP4rjk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=sgdk/o5cRyDQfSz7DafTRzaXAR4bdA8m1WQPpyAMQO0zeaG4aVSKVjYVn9i+N84jm jFXKREq871g73Ya6laLrk2CNoFxQkJrxY0a86UvFWsdX2LATca7mMfRmlK+cTpEbo9 2uDPa7B4LSYg8SAc7xOIK7k2wOxyQdfUmQihXfwY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390122AbfDRSbo (ORCPT ); Thu, 18 Apr 2019 14:31:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:56264 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389998AbfDRSAv (ORCPT ); Thu, 18 Apr 2019 14:00:51 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 353E7217FA; Thu, 18 Apr 2019 18:00:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555610450; bh=9dYun8rVuXmR92OQcnQbnMiLZwOPW92CXr+aDxP4rjk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IItwOSawb9KRR8tQICQlYw59WD3kjlXnsfbmMoPvm0XN32EB1b+meMUuy3IWJV9jm umc37DsqOdOeu7vw+nXgb66WbA7wYKNYZWqRVI+iR9m4bbqz8F+/E1tPN9FYK5YWPL /2nw+svPho5RFeBZlE8JTreUqifayRFNlAIl/HfI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yanjiang Jin , Linus Walleij , Sasha Levin Subject: [PATCH 4.19 067/110] pinctrl: core: make sure strcmp() doesnt get a null parameter Date: Thu, 18 Apr 2019 19:56:56 +0200 Message-Id: <20190418160444.716957105@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190418160437.484158340@linuxfoundation.org> References: <20190418160437.484158340@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 54a58185bfafb5af5045fb8388c45daa373f90f3 ] Some drivers, for example, QCOM's qdf2xxx, set groups[gpio].name only when gpio is valid, and leave invalid gpio names as null. If we want to access the sys node "pinconf-groups", pinctrl_get_group_selector() -> get_group_name() may return a null pointer if group_selector is invalid, then the below Kernel panic would happen since strcmp() uses this null pointer to do comparison. Unable to handle kernel NULL pointer dereference at ss 00000000 el:Internal error: Oops: 9600000[ 143.080279] SMP CPU: 19 PID: 2493 Comm: read_all Tainted: G O .aarch64 #1 Hardware name: HXT Semiconductor HXT REP-2 System PC is at strcmp+0x18/0x154 LR is at pinctrl_get_group_selector+0x6c/0xe8 Process read_all (pid: 2493, stack limit = Call trace: Exception stack strcmp+0x18/0x154 pin_config_group_get+0x64/0xd8 pinconf_generic_dump_one+0xd8/0x1c0 pinconf_generic_dump_pins+0x94/0xc8 pinconf_groups_show+0xb4/0x104 seq_read+0x178/0x464 full_proxy_read+0x6c/0xac __vfs_read+0x58/0x178 vfs_read+0x94/0x164 SyS_read+0x60/0xc0 __sys_trace_return+0x0/0x4 --[ end trace]-- Kernel panic - not syncing: Fatal exception Signed-off-by: Yanjiang Jin Signed-off-by: Linus Walleij Signed-off-by: Sasha Levin --- drivers/pinctrl/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index a3dd777e3ce8..c6ff4d5fa482 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -627,7 +627,7 @@ static int pinctrl_generic_group_name_to_selector(struct pinctrl_dev *pctldev, while (selector < ngroups) { const char *gname = ops->get_group_name(pctldev, selector); - if (!strcmp(function, gname)) + if (gname && !strcmp(function, gname)) return selector; selector++; @@ -743,7 +743,7 @@ int pinctrl_get_group_selector(struct pinctrl_dev *pctldev, while (group_selector < ngroups) { const char *gname = pctlops->get_group_name(pctldev, group_selector); - if (!strcmp(gname, pin_group)) { + if (gname && !strcmp(gname, pin_group)) { dev_dbg(pctldev->dev, "found group selector %u for %s\n", group_selector, -- 2.19.1