From patchwork Mon Jul 19 14:52:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 480468 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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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=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 66856C6377E for ; Mon, 19 Jul 2021 16:26:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53ADA61166 for ; Mon, 19 Jul 2021 16:26:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348564AbhGSPoK (ORCPT ); Mon, 19 Jul 2021 11:44:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:34938 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344345AbhGSPlV (ORCPT ); Mon, 19 Jul 2021 11:41:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D44261107; Mon, 19 Jul 2021 16:21:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626711666; bh=dg6PZhYDKEu5IrfYdh2th0q3Fhb88QjwQKmagB8cjX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bEGjWpeKGHMHg4BcbxOoIM24UiCDQM45Zhfvk8VDzYqqHfUtXlJi2wqatpye2IO5h RJUyC5w5WbHpc0GsBpiuwsXduPKC51+8pk4tm1Msx4tAO7Sw/OZPSWvHlsjB11q6zN UvKwmULhxNmvl3m8mkU182wd2BkMAxmA1WE/p1rg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiyu Yang , Xin Tan , Will Deacon , Sasha Levin Subject: [PATCH 5.12 088/292] iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails Date: Mon, 19 Jul 2021 16:52:30 +0200 Message-Id: <20210719144945.407746801@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144942.514164272@linuxfoundation.org> References: <20210719144942.514164272@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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/arm-smmu/arm-smmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c index d8c6bfde6a61..128c2c87b4e5 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c @@ -74,7 +74,7 @@ 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; }