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,USER_AGENT_GIT autolearn=unavailable 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 30FD0C433E1 for ; Wed, 31 Mar 2021 01:46:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E66FD619C1 for ; Wed, 31 Mar 2021 01:46:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233116AbhCaBph (ORCPT ); Tue, 30 Mar 2021 21:45:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232859AbhCaBpL (ORCPT ); Tue, 30 Mar 2021 21:45:11 -0400 Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 77C53C061574; Tue, 30 Mar 2021 18:45:05 -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=R+YO8TACOX GNoVNl3MxR9+6Lq0q8OS7rvRzgBfzXiNc=; b=TqqwmyGc3guTwopvJmg61IIeO1 uESz4QtlRonocY06qNOe13nuHEfPd/HE0KDXFvr1qyHaus99TXz//zeBXKu8Lzkv hWVwDvCoSrjAPOrgrNkL+TYcKFWqXzp3AJupiVfd5Fo6jOwPlliIeGWTtdpOswzm MwG/g3fmHm5OaOvfU= Received: from ubuntu.localdomain (unknown [202.38.69.14]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygCnrU0e1GNg5J90AA--.440S4; Wed, 31 Mar 2021 09:45:02 +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 v2] dma: Fix a double free in dma_async_device_register Date: Tue, 30 Mar 2021 18:44:58 -0700 Message-Id: <20210331014458.3944-1-lyl2019@mail.ustc.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: LkAmygCnrU0e1GNg5J90AA--.440S4 X-Coremail-Antispam: 1UD129KBjvJXoW7ZF4kKw4kGr4kXF17GF17ZFb_yoW8Jw1kpr sxGa45KFW2qa15ZFsxXr1FvFyUu3Z8J34F93yqyw1akrZxZr92yw48ta1j9a4DJws3JF4f Kas5J34fuF47Cr7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvl14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26F1j6w1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26F4UJVW0owA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Cr 1j6rxdM2vYz4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVAC Y4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJV W8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI2 0VAGYxC7MxkIecxEwVAFwVWkMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r 4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF 67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2I x0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_WFyUJVCq3wCI42IY 6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r1j6r4UYxBIdaVFxhVjvj DU0xZFpf9x0JUmNtcUUUUU= X-CM-SenderInfo: ho1ojiyrz6zt1loo32lwfovvfxof0/ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index fe6a460c4373..af3ee288bc11 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -1086,6 +1086,7 @@ static int __dma_async_device_channel_register(struct dma_device *device, kfree(chan->dev); err_free_local: free_percpu(chan->local); + chan->local = NULL; return rc; } -- 2.25.1