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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 9B4C8C11F6C for ; Sat, 10 Jul 2021 02:33:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86631613B7 for ; Sat, 10 Jul 2021 02:33:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234188AbhGJCga (ORCPT ); Fri, 9 Jul 2021 22:36:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:48926 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234094AbhGJCbz (ORCPT ); Fri, 9 Jul 2021 22:31:55 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2F0CA6143D; Sat, 10 Jul 2021 02:27:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625884076; bh=owq9dcDj6W5tIDWtWgDI7aDMSiBLW0RSApzKwfmDGlM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TYlwyB0eGUIWJvxe+D1/rTYjJiWVzwJruYqJgtUb87dkrzx1hlHR10GBMCq+GpGUU eMgqM3pQXQeqjZ1+p3lOyH4zEXtHMoXAW20irUS/7UscvV3oMA/qfQgAel6dkkwsQA pVoM7SNVsU9FGFdD1YFMhQb6h3gZo7zQjjjVx9CTM+OWKwOCuA5w2Lva1BCjGJxycP UQwwrrQprbbEXaSM07YJgkieU1x6TMQJlzhRDqJklC1CyzhPvDqYCiDflDCAxz8+Cm 252YA6P9lMG+7ydxDp/NJzvMhLDPj4zFuEy3RHbXpE4MJL8R85zmMk3SW06G+j2mj0 mtXupOR7MAE/g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Xiyu Yang , Xin Tan , Will Deacon , Sasha Levin , iommu@lists.linux-foundation.org Subject: [PATCH AUTOSEL 5.4 36/63] iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails Date: Fri, 9 Jul 2021 22:26:42 -0400 Message-Id: <20210710022709.3170675-36-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210710022709.3170675-1-sashal@kernel.org> References: <20210710022709.3170675-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiyu Yang [ Upstream commit 1adf30f198c26539a62d761e45af72cde570413d ] arm_smmu_rpm_get() invokes pm_runtime_get_sync(), which increases the refcount of the "smmu" even though the return value is less than 0. The reference counting issue happens in some error handling paths of arm_smmu_rpm_get() in its caller functions. When arm_smmu_rpm_get() fails, the caller functions forget to decrease the refcount of "smmu" increased by arm_smmu_rpm_get(), causing a refcount leak. Fix this issue by calling pm_runtime_resume_and_get() instead of pm_runtime_get_sync() in arm_smmu_rpm_get(), which can keep the refcount balanced in case of failure. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Link: https://lore.kernel.org/r/1623293672-17954-1-git-send-email-xiyuyang19@fudan.edu.cn Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/iommu/arm-smmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 7c503a6bc585..abf4cf285548 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -114,7 +114,7 @@ static bool using_legacy_binding, using_generic_binding; static inline int arm_smmu_rpm_get(struct arm_smmu_device *smmu) { if (pm_runtime_enabled(smmu->dev)) - return pm_runtime_get_sync(smmu->dev); + return pm_runtime_resume_and_get(smmu->dev); return 0; } -- 2.30.2