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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 66000C433DF for ; Thu, 18 Jun 2020 02:06:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3674220885 for ; Thu, 18 Jun 2020 02:06:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592445987; bh=B3HdxUBiJCU32sbuk444sodIJkPGhv+mpEKr9pRgcY4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=R16MLIOMPLVwRpich0UHCQpoBUAGytuETHrpv9yCZbr4nT2cmj0QE1/Pxe34Yednw cHqLNuVOpQeB/su/wqd22zQvNkLuhDfY0MKfP77Slf7A8TRpcUfU0P9vUhgp6v4t7Q 67F9eIpYRZH6rMroi4b1EQatszAc3fHrMhIQMMXE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732029AbgFRCGZ (ORCPT ); Wed, 17 Jun 2020 22:06:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:55604 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730757AbgFRBWd (ORCPT ); Wed, 17 Jun 2020 21:22:33 -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 1FA7320663; Thu, 18 Jun 2020 01:22:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592443353; bh=B3HdxUBiJCU32sbuk444sodIJkPGhv+mpEKr9pRgcY4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ndn8eVjJ8XEacRN2xWTQLlc4DWG/NWJDk13VJpng/qg+dVipzXeQTaKLF5pICUwiN tlCO0O+KuoYUIZJa4d/0wykn4R/Kg0RdM6EZEhNte26o6DV8M9+Fe4bnX/2cC200WA mDPhHH4IZH5c+mnLq9ILG1X4Z31BE3WS5/Y2/K+I= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Xiyu Yang , Xin Tan , Peter Ujfalusi , Mark Brown , Sasha Levin , alsa-devel@alsa-project.org Subject: [PATCH AUTOSEL 4.19 011/172] ASoC: davinci-mcasp: Fix dma_chan refcnt leak when getting dma type Date: Wed, 17 Jun 2020 21:19:37 -0400 Message-Id: <20200618012218.607130-11-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200618012218.607130-1-sashal@kernel.org> References: <20200618012218.607130-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review 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: Xiyu Yang [ Upstream commit a697ae6ea56e23397341b027098c1b11d9ab13da ] davinci_mcasp_get_dma_type() invokes dma_request_chan(), which returns a reference of the specified dma_chan object to "chan" with increased refcnt. When davinci_mcasp_get_dma_type() returns, local variable "chan" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of davinci_mcasp_get_dma_type(). When chan device is NULL, the function forgets to decrease the refcnt increased by dma_request_chan(), causing a refcnt leak. Fix this issue by calling dma_release_channel() when chan device is NULL. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Acked-by: Peter Ujfalusi Link: https://lore.kernel.org/r/1587818916-38730-1-git-send-email-xiyuyang19@fudan.edu.cn Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- sound/soc/davinci/davinci-mcasp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c index 14ab16e1369f..1203de8aab99 100644 --- a/sound/soc/davinci/davinci-mcasp.c +++ b/sound/soc/davinci/davinci-mcasp.c @@ -1758,8 +1758,10 @@ static int davinci_mcasp_get_dma_type(struct davinci_mcasp *mcasp) PTR_ERR(chan)); return PTR_ERR(chan); } - if (WARN_ON(!chan->device || !chan->device->dev)) + if (WARN_ON(!chan->device || !chan->device->dev)) { + dma_release_channel(chan); return -EINVAL; + } if (chan->device->dev->of_node) ret = of_property_read_string(chan->device->dev->of_node, -- 2.25.1