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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 62FA7C10F0B for ; Thu, 18 Apr 2019 07:24:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 25352214DA for ; Thu, 18 Apr 2019 07:24:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="Q1sf1Rhk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388152AbfDRHX7 (ORCPT ); Thu, 18 Apr 2019 03:23:59 -0400 Received: from m50-132.163.com ([123.125.50.132]:41047 "EHLO m50-132.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731317AbfDRHX6 (ORCPT ); Thu, 18 Apr 2019 03:23:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=A2avxIEXMxtUFGqdlf UaJw2dGK5fmozKEPD9FwObH70=; b=Q1sf1Rhku4O9XOBto8Sjj0Gd2pxHy4Z5AH nuo2LuqplfA64do2+Ibq9t0wNt4N8TZPUeQikn3BFBPAOVhIxiAj0N2i1Y/HL6+f oGkN/EyRZCWC4TToyPMKbadPhzUEESDh1isKIGJIMzCN0KaaLvnp93wPg7pG2Z9o 1ZlnOmXlU= Received: from bp.localdomain (unknown [218.106.182.174]) by smtp2 (Coremail) with SMTP id DNGowACniR_TJbhcX+MIAA--.174S3; Thu, 18 Apr 2019 15:23:06 +0800 (CST) From: Pan Bian To: Alexander Shishkin , Maxime Coquelin , Alexandre Torgue Cc: linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Pan Bian Subject: stm class: Fix possible double free Date: Thu, 18 Apr 2019 15:22:58 +0800 Message-Id: <1555572178-73786-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: DNGowACniR_TJbhcX+MIAA--.174S3 X-Coremail-Antispam: 1Uf129KBjvJXoW7try3Cw4DAr1kCr1kKw1ftFb_yoW8GF43pa 18Ga4Yyry8Krsrur1DJF18ZFy5GayIkw1ruFy0kwna9FZ8Z34vyryYya45CayDJrW8AFWa qFW3ArW8ur1UAw7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07UlkskUUUUU= X-Originating-IP: [218.106.182.174] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBZBKaclQHEfe2+AAAsl Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function stm_register_device() calls put_device(&stm->dev) to release allocated memory (in stm_device_release()) on error paths. However, after that, the freed memory stm is released again, resulting in a double free bug. There is a similar issue in the function stm_source_register_device. This patch fixes these issues. Signed-off-by: Pan Bian --- drivers/hwtracing/stm/core.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index c7ba8ac..cfb5c4d 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -886,8 +886,10 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, return -ENOMEM; stm->major = register_chrdev(0, stm_data->name, &stm_fops); - if (stm->major < 0) - goto err_free; + if (stm->major < 0) { + vfree(stm); + return err; + } device_initialize(&stm->dev); stm->dev.devt = MKDEV(stm->major, 0); @@ -933,8 +935,6 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, /* matches device_initialize() above */ put_device(&stm->dev); -err_free: - vfree(stm); return err; } @@ -1277,7 +1277,6 @@ int stm_source_register_device(struct device *parent, err: put_device(&src->dev); - kfree(src); return err; } -- 2.7.4