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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 ECA19C43381 for ; Sat, 30 Mar 2019 01:29:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB2C6218E2 for ; Sat, 30 Mar 2019 01:29:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553909370; bh=eBZUywteNKvuDQ3xoiq3Xg8hQIPWQ4S+HTBb1ym2EiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=x6cxX4baSblVxGNyiDbqeyUUbjEOowyjc3D4Uy76S/EJdK3MnkLLovmrrbDSRj6zp C3cti5Of9kadEUHqC/UvU8eB6dwcvNtxf9QSwpkWJw+UhyvmBmIahMaDpZqG52xamx Guzij2syHXDCJM5oV1glH43GeRezFFfJp+Euzuxk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730965AbfC3B3a (ORCPT ); Fri, 29 Mar 2019 21:29:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:36356 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730941AbfC3B33 (ORCPT ); Fri, 29 Mar 2019 21:29:29 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D69E2217F5; Sat, 30 Mar 2019 01:29:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553909368; bh=eBZUywteNKvuDQ3xoiq3Xg8hQIPWQ4S+HTBb1ym2EiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PBB+Z4zN5or8naJMMurz+xp1HuEt8nb5nJDYCv03jPJgzZWuZ5M8nUjLh0dz+TRES XwUBQzIZ/usjhVFX5dULW7gsFALUSNCkNniQnHucawKhix27JrrOSyn86mqHtspqna Fi/7mmmVIIKd/zqSfsIithri0WIYZv9J7pKGr7sc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yanjiang Jin , Linus Walleij , Sasha Levin , linux-gpio@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 15/57] pinctrl: core: make sure strcmp() doesn't get a null parameter Date: Fri, 29 Mar 2019 21:28:08 -0400 Message-Id: <20190330012854.32212-15-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190330012854.32212-1-sashal@kernel.org> References: <20190330012854.32212-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yanjiang Jin [ 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