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, URIBL_BLOCKED,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 D95CCC43381 for ; Wed, 27 Mar 2019 18:49:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F2FF205C9 for ; Wed, 27 Mar 2019 18:49:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553712591; bh=hD2RJPnaS6Es29brTXoGgh69te7zm5LCCsCvee9+LEs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fvbut2hKeTwQ+1TQ1X+AjH1fIsyz6syvmpJH0osVJ5jD6kyliW31PEr0lp/EdWuXC kSLS11FuoDV0jspB++zaa0pHMtb6mZgALPpojlrGHfk2sfIdObmeBRvercrT9sh3MG LJLb9rIC3/1qZP3vhWENtVydpRSPS52M787LtQLw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390531AbfC0SSc (ORCPT ); Wed, 27 Mar 2019 14:18:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:35268 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390509AbfC0SSZ (ORCPT ); Wed, 27 Mar 2019 14:18:25 -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 7A5182147C; Wed, 27 Mar 2019 18:18:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710704; bh=hD2RJPnaS6Es29brTXoGgh69te7zm5LCCsCvee9+LEs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RINpthu572oMWeOyUpaHZ6EQ7g/72ZQbDrDCbRccumRkV1h1zkN+JfG/8TYUXwJVY ieBN++4N93CpeQiOKErizgX92oWWry/Q3IR5GJGPd/n6Tx6BF098tXC9pLQufikB2h o9e4X3flj+8tTKr+DBAhwTuxIxb6eslcIlC0NVXQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Michal Kazior , Jacek Anaszewski , Sasha Levin , linux-leds@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 065/123] leds: lp55xx: fix null deref on firmware load failure Date: Wed, 27 Mar 2019 14:15:29 -0400 Message-Id: <20190327181628.15899-65-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327181628.15899-1-sashal@kernel.org> References: <20190327181628.15899-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Kazior [ Upstream commit 5ddb0869bfc1bca6cfc592c74c64a026f936638c ] I've stumbled upon a kernel crash and the logs pointed me towards the lp5562 driver: > <4>[306013.841294] lp5562 0-0030: Direct firmware load for lp5562 failed with error -2 > <4>[306013.894990] lp5562 0-0030: Falling back to user helper > ... > <3>[306073.924886] lp5562 0-0030: firmware request failed > <1>[306073.939456] Unable to handle kernel NULL pointer dereference at virtual address 00000000 > <4>[306074.251011] PC is at _raw_spin_lock+0x1c/0x58 > <4>[306074.255539] LR is at release_firmware+0x6c/0x138 > ... After taking a look I noticed firmware_release() could be called with either NULL or a dangling pointer. Fixes: 10c06d178df11 ("leds-lp55xx: support firmware interface") Signed-off-by: Michal Kazior Signed-off-by: Jacek Anaszewski Signed-off-by: Sasha Levin --- drivers/leds/leds-lp55xx-common.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/leds/leds-lp55xx-common.c b/drivers/leds/leds-lp55xx-common.c index 5377f22ff994..e2655953667c 100644 --- a/drivers/leds/leds-lp55xx-common.c +++ b/drivers/leds/leds-lp55xx-common.c @@ -201,7 +201,7 @@ static void lp55xx_firmware_loaded(const struct firmware *fw, void *context) if (!fw) { dev_err(dev, "firmware request failed\n"); - goto out; + return; } /* handling firmware data is chip dependent */ @@ -214,9 +214,9 @@ static void lp55xx_firmware_loaded(const struct firmware *fw, void *context) mutex_unlock(&chip->lock); -out: /* firmware should be released for other channel use */ release_firmware(chip->fw); + chip->fw = NULL; } static int lp55xx_request_firmware(struct lp55xx_chip *chip) -- 2.19.1