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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 F13D4C282DA for ; Sun, 3 Feb 2019 14:21:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C86DA2084A for ; Sun, 3 Feb 2019 14:21:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729172AbfBCOV4 (ORCPT ); Sun, 3 Feb 2019 09:21:56 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:55992 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730690AbfBCOVy (ORCPT ); Sun, 3 Feb 2019 09:21:54 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqIee-0006Ur-O3; Sun, 03 Feb 2019 14:21:52 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqI9d-00076e-86; Sun, 03 Feb 2019 14:49:49 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Geert Uytterhoeven" , "Joerg Roedel" , "Robin Murphy" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 162/305] iommu/ipmmu-vmsa: Fix crash on early domain free In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Geert Uytterhoeven commit e5b78f2e349eef5d4fca5dc1cf5a3b4b2cc27abd upstream. If iommu_ops.add_device() fails, iommu_ops.domain_free() is still called, leading to a crash, as the domain was only partially initialized: ipmmu-vmsa e67b0000.mmu: Cannot accommodate DMA translation for IOMMU page tables sata_rcar ee300000.sata: Unable to initialize IPMMU context iommu: Failed to add device ee300000.sata to group 0: -22 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038 ... Call trace: ipmmu_domain_free+0x1c/0xa0 iommu_group_release+0x48/0x68 kobject_put+0x74/0xe8 kobject_del.part.0+0x3c/0x50 kobject_put+0x60/0xe8 iommu_group_get_for_dev+0xa8/0x1f0 ipmmu_add_device+0x1c/0x40 of_iommu_configure+0x118/0x190 Fix this by checking if the domain's context already exists, before trying to destroy it. Signed-off-by: Geert Uytterhoeven Reviewed-by: Robin Murphy Fixes: d25a2a16f0889 ('iommu: Add driver for Renesas VMSA-compatible IPMMU') Signed-off-by: Joerg Roedel Signed-off-by: Ben Hutchings --- drivers/iommu/ipmmu-vmsa.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/iommu/ipmmu-vmsa.c +++ b/drivers/iommu/ipmmu-vmsa.c @@ -383,6 +383,9 @@ static int ipmmu_domain_init_context(str static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain) { + if (!domain->mmu) + return; + /* * Disable the context. Flush the TLB as required when modifying the * context registers.