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=-9.7 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_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 911C7C5DF61 for ; Thu, 7 Nov 2019 11:27:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5CC7021882 for ; Thu, 7 Nov 2019 11:27:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="b6XWFLM1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388199AbfKGL1g (ORCPT ); Thu, 7 Nov 2019 06:27:36 -0500 Received: from mail-m975.mail.163.com ([123.126.97.5]:47592 "EHLO mail-m975.mail.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727278AbfKGL1g (ORCPT ); Thu, 7 Nov 2019 06:27:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=VxXuxyye1MqjU+hDjg 02qbrKx1jLX10dIV/GDARuXpU=; b=b6XWFLM1DY02QNi+PAd31aRrO6jgY1b51z UiunWg4MGfA6LGfW9dtQeS44ggK81ISAo3d/cBoRqO0KR+B3yIph2aZ2OiKLRr6m jW65MQHNHjtcxF2DbkDaCdId16uGV6fd4mXFuA7MkaGAJM3laVsNWXn9IEIsIXYJ IiVR1ElHI= Received: from localhost.localdomain (unknown [202.112.113.212]) by smtp5 (Coremail) with SMTP id HdxpCgCXTueP_8Nd8iYXAA--.227S3; Thu, 07 Nov 2019 19:27:17 +0800 (CST) From: Pan Bian To: Dan Williams , Vinod Koul , Maxime Ripard , Chen-Yu Tsai Cc: dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH] dmaengine: sun6i: Fix use after free Date: Thu, 7 Nov 2019 19:26:53 +0800 Message-Id: <1573126013-17609-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: HdxpCgCXTueP_8Nd8iYXAA--.227S3 X-Coremail-Antispam: 1Uf129KBjvJXoW7Zr17Kr15JFy3XrWfGryfZwb_yoW8KF1kpF 43Ja4rur45tF1aga13Z348uF13KF4fJFyUCay5Gwn0vr9xXr1kGa17Aa4Fkr98JFn8CrWf Xrs0gF1ruF4UGwUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07UypBhUUUUU= X-Originating-IP: [202.112.113.212] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBzxVmclaD5QFnNAAAss Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The members in the LLI list is released in an incorrect way. Read and store the next member before releasing it to avoid accessing the freed memory. Fixes: a90e173f3faf ("dmaengine: sun6i: Add cyclic capability") Signed-off-by: Pan Bian --- drivers/dma/sun6i-dma.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c index 06cd7f867f7c..096aad7e75bb 100644 --- a/drivers/dma/sun6i-dma.c +++ b/drivers/dma/sun6i-dma.c @@ -687,7 +687,7 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg( struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); struct sun6i_vchan *vchan = to_sun6i_vchan(chan); struct dma_slave_config *sconfig = &vchan->cfg; - struct sun6i_dma_lli *v_lli, *prev = NULL; + struct sun6i_dma_lli *v_lli, *next, *prev = NULL; struct sun6i_desc *txd; struct scatterlist *sg; dma_addr_t p_lli; @@ -752,8 +752,12 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg( return vchan_tx_prep(&vchan->vc, &txd->vd, flags); err_lli_free: - for (prev = txd->v_lli; prev; prev = prev->v_lli_next) - dma_pool_free(sdev->pool, prev, virt_to_phys(prev)); + v_lli = txd->v_lli; + while (v_lli) { + next = v_lli->v_lli_next; + dma_pool_free(sdev->pool, v_lli, virt_to_phys(v_lli)); + v_lli = next; + } kfree(txd); return NULL; } @@ -769,7 +773,7 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic( struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); struct sun6i_vchan *vchan = to_sun6i_vchan(chan); struct dma_slave_config *sconfig = &vchan->cfg; - struct sun6i_dma_lli *v_lli, *prev = NULL; + struct sun6i_dma_lli *v_lli, *next, *prev = NULL; struct sun6i_desc *txd; dma_addr_t p_lli; u32 lli_cfg; @@ -820,8 +824,12 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic( return vchan_tx_prep(&vchan->vc, &txd->vd, flags); err_lli_free: - for (prev = txd->v_lli; prev; prev = prev->v_lli_next) - dma_pool_free(sdev->pool, prev, virt_to_phys(prev)); + v_lli = txd->v_lli; + while (v_lli) { + next = v_lli->v_lli_next; + dma_pool_free(sdev->pool, v_lli, virt_to_phys(v_lli)); + v_lli = next; + } kfree(txd); return NULL; } -- 2.7.4