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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 924D1C433DB for ; Tue, 30 Mar 2021 09:02:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A2C861959 for ; Tue, 30 Mar 2021 09:02:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231671AbhC3JCU (ORCPT ); Tue, 30 Mar 2021 05:02:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231728AbhC3JCD (ORCPT ); Tue, 30 Mar 2021 05:02:03 -0400 Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A8AB4C061762; Tue, 30 Mar 2021 02:01:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mail.ustc.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:MIME-Version:Content-Transfer-Encoding; bh=jVd5Fj47PE AEha0HxIJGwUYTFQoLyWB97glqQoEC1No=; b=On6BM+sBlxe/M3e/opvNqT11Fw qDsvFMqyAs1PPWL3ZW2+aOQYLVs1t/QAqDp4XAlQwt7G7KO0X38cNkFQafeo7YiQ OKMXzLB53y+6udU8yteaqQKuLcwILyRyzB8uyHNohD6PqmRtheBizCChtyhW6SHz kUOL6IqT91u8PFZTY= Received: from ubuntu.localdomain (unknown [202.38.69.14]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygDHz6cA6WJgVRxvAA--.97S4; Tue, 30 Mar 2021 17:01:52 +0800 (CST) From: Lv Yunlong To: vkoul@kernel.org, dave.jiang@intel.com Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, Lv Yunlong Subject: [PATCH] dma: Fix a double free in dma_async_device_register Date: Tue, 30 Mar 2021 02:01:49 -0700 Message-Id: <20210330090149.13476-1-lyl2019@mail.ustc.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: LkAmygDHz6cA6WJgVRxvAA--.97S4 X-Coremail-Antispam: 1UD129KBjvJXoW7ZF4kKw4kGr4kXF17GF17ZFb_yoW8XF15pr ZxGa43GFWjqa15ZF47Xr15ZFyUW3Z8t3yF93yqkw12krZxXr929w48t3yj9a4DJw43JF4f KF98J34fuFsrCw7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvl14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1lnxkEFVAIw20F6cxK64vIFxWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xv F2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r 4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I 648v4I1lc2xSY4AK67AK6r4fMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r 4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF 67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2I x0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_WFyUJVCq3wCI42IY 6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r1j6r4UYxBIdaVFxhVjvj DU0xZFpf9x0JUS0P-UUUUU= X-CM-SenderInfo: ho1ojiyrz6zt1loo32lwfovvfxof0/ Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org In the first list_for_each_entry() macro of dma_async_device_register, it gets the chan from list and calls __dma_async_device_channel_register (..,chan). We can see that chan->local is allocated by alloc_percpu() and it is freed chan->local by free_percpu(chan->local) when __dma_async_device_channel_register() failed. But after __dma_async_device_channel_register() failed, the caller will goto err_out and freed the chan->local in the second time by free_percpu(). The cause of this problem is forget to set chan->local to NULL when chan->local was freed in __dma_async_device_channel_register(). My patch sets chan->local to NULL when the callee failed to avoid double free. Fixes: d2fb0a0438384 ("dmaengine: break out channel registration") Signed-off-by: Lv Yunlong --- drivers/dma/dmaengine.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index fe6a460c4373..fef64b198c95 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -1249,8 +1249,10 @@ int dma_async_device_register(struct dma_device *device) /* represent channels in sysfs. Probably want devs too */ list_for_each_entry(chan, &device->channels, device_node) { rc = __dma_async_device_channel_register(device, chan); - if (rc < 0) + if (rc < 0) { + chan->local = NULL; goto err_out; + } } mutex_lock(&dma_list_mutex); -- 2.25.1