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,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 E29F2C433EF for ; Fri, 10 Sep 2021 00:43:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8FD1611BD for ; Fri, 10 Sep 2021 00:43:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233556AbhIJAog (ORCPT ); Thu, 9 Sep 2021 20:44:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:46530 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233569AbhIJAUV (ORCPT ); Thu, 9 Sep 2021 20:20:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6258C610A3; Fri, 10 Sep 2021 00:19:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631233151; bh=2Rb8pAo61id0/qvD1+/iwJWQ3LQzfOrKbsYuJ0pBJL0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TRotO7Vbqz79bKIn31GHnbRXvJcTnxGiT2KIeviOYS5OMIqk0a/eBhjnV3xjmoIW1 dWsRF9FHWlwMquspD0NzT9iSB8E3eiXf+3MVr5mo8ddeZ6VgFL8YK7zG/bDeNBWkYS uS/1w3slxsUbj8or6DX4dqeo2hBOzeQbf6cFWFECk1pU+SOosLALklTtdiSCyguUq/ vvCrdYIN0n6cluHak9dfkBss9OYS1e9bI9Ns5633hYX7D5aWAqXK0/Eb8npBbl+EN7 3RUxSYZWccDF0WyEHdkuctj2L296i66x6Uovr6vH1WPWx6gYdvj1pmrbkC/JbYu49b 91e7e22lQ/WXA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ashish Mhetre , Will Deacon , Sasha Levin , iommu@lists.linux-foundation.org Subject: [PATCH AUTOSEL 5.13 35/88] iommu: Fix race condition during default domain allocation Date: Thu, 9 Sep 2021 20:17:27 -0400 Message-Id: <20210910001820.174272-35-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210910001820.174272-1-sashal@kernel.org> References: <20210910001820.174272-1-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: stable@vger.kernel.org From: Ashish Mhetre [ Upstream commit 211ff31b3d33b56aa12937e898c9280d07daf0d9 ] When two devices with same SID are getting probed concurrently through iommu_probe_device(), the iommu_domain sometimes is getting allocated more than once as call to iommu_alloc_default_domain() is not protected for concurrency. Furthermore, it leads to each device holding a different iommu_domain pointer, separate IOVA space and only one of the devices' domain is used for translations from IOMMU. This causes accesses from other device to fault or see incorrect translations. Fix this by protecting iommu_alloc_default_domain() call with group->mutex and let all devices with same SID share same iommu_domain. Signed-off-by: Ashish Mhetre Link: https://lore.kernel.org/r/1628570641-9127-2-git-send-email-amhetre@nvidia.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/iommu/iommu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index db966a7841fe..f4d0bab6be10 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -273,7 +273,9 @@ int iommu_probe_device(struct device *dev) * support default domains, so the return value is not yet * checked. */ + mutex_lock(&group->mutex); iommu_alloc_default_domain(group, dev); + mutex_unlock(&group->mutex); if (group->default_domain) { ret = __iommu_attach_device(group->default_domain, dev); -- 2.30.2