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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 A91EBC43603 for ; Tue, 17 Dec 2019 17:55:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7E1F4206EC for ; Tue, 17 Dec 2019 17:55:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Llkj7s5+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727753AbfLQRzy (ORCPT ); Tue, 17 Dec 2019 12:55:54 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:59646 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726722AbfLQRzy (ORCPT ); Tue, 17 Dec 2019 12:55:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576605353; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=M7e6SsR0adMoPhT0GmsplLfMKmkYiVgsu5hzgKJZohY=; b=Llkj7s5+G6IEvDPQIiO0yP4Bf6y5Eb7idn77JreQY94swSOn7LSrjpKaznL4DbFCNIFM4b LD1lNWlyebOQ509yGrjnb/mFxDavR0aPX1ud06GxTro/5FfeMCS5O5fv1fyUlkn3eXQUP1 jQZppxIXPGcCCfdeFGiyabYmFMU/Hnw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-40-L6si89IqOXGqVPyM0K9y6A-1; Tue, 17 Dec 2019 12:55:49 -0500 X-MC-Unique: L6si89IqOXGqVPyM0K9y6A-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 26415107ACC5; Tue, 17 Dec 2019 17:55:48 +0000 (UTC) Received: from cantor.redhat.com (ovpn-116-112.phx2.redhat.com [10.3.116.112]) by smtp.corp.redhat.com (Postfix) with ESMTP id A9C542657B; Tue, 17 Dec 2019 17:55:47 +0000 (UTC) From: Jerry Snitselaar To: linux-kernel@vger.kernel.org Cc: Joerg Roedel , Lu Baolu , David Woodhouse , stable@vger.kernel.org, iommu@lists.linux-foundation.org Subject: [RFC PATCH] iommu/vt-d: avoid panic in __dmar_remove_one_dev_info Date: Tue, 17 Dec 2019 10:55:42 -0700 Message-Id: <20191217175542.22187-1-jsnitsel@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In addition to checking for a null pointer, verify that info does not have the value DEFER_DEVICE_DOMAIN_INFO or DUMMY_DEVICE_DOMAIN_INFO. If info has one of those values __dmar_remove_one_dev_info will panic when trying to access a member of the device_domain_info struct. [ 1.464241] BUG: unable to handle kernel NULL pointer dereference = at 000000000000004e [ 1.464241] PGD 0 P4D 0 [ 1.464241] Oops: 0000 [#1] SMP PTI [ 1.464241] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W = --------- - - 4.18.0-160.el8.x86_64 #1 [ 1.464241] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 G= en9, BIOS P89 07/21/2019 [ 1.464241] RIP: 0010:__dmar_remove_one_dev_info+0x27/0x250 [ 1.464241] Code: 00 00 00 0f 1f 44 00 00 8b 05 35 ec 75 01 41 56 = 41 55 41 54 55 53 85 c0 0f 84 99 01 00 00 48 85 ff 0f 84 92 01 00 00 48 8= 9 fb <4c> 8b 67 50 48 8b 6f 58 $ [ 1.464241] RSP: 0000:ffffc900000dfd10 EFLAGS: 00010082 [ 1.464241] RAX: 0000000000000001 RBX: fffffffffffffffe RCX: 00000= 00000000000 [ 1.464241] RDX: 0000000000000001 RSI: 0000000000000004 RDI: fffff= ffffffffffe [ 1.464241] RBP: ffff88ec7a72f368 R08: 0000000000000457 R09: 00000= 00000000039 [ 1.464241] R10: 0000000000000000 R11: ffffc900000dfa58 R12: ffff8= 8ec7a0eec20 [ 1.464241] R13: ffff88ec6fd0eab0 R14: ffffffff81eae980 R15: 00000= 00000000000 [ 1.464241] FS: 0000000000000000(0000) GS:ffff88ec7a600000(0000) = knlGS:0000000000000000 [ 1.464241] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.464241] CR2: 000000000000004e CR3: 0000006c7900a001 C 00000000= 001606b0 [ 1.464241] Call Trace: [ 1.464241] dmar_remove_one_dev_info.isra.68+0x27/0x40 [ 1.464241] intel_iommu_add_device+0x124/0x180 [ 1.464241] ? iommu_probe_device+0x40/0x40 [ 1.464241] add_iommu_group+0xa/0x20 [ 1.464241] bus_for_each_dev+0x77/0xc0 [ 1.464241] ? down_write+0xe/0x40 [ 1.464241] bus_set_iommu+0x85/0xc0 [ 1.464241] intel_iommu_init+0x4b4/0x777 [ 1.464241] ? e820__memblock_setup+0x63/0x63 [ 1.464241] ? do_early_param+0x91/0x91 [ 1.464241] pci_iommu_init+0x19/0x45 [ 1.464241] do_one_initcall+0x46/0x1c3 [ 1.464241] ? do_early_param+0x91/0x91 [ 1.464241] kernel_init_freeable+0x1af/0x258 [ 1.464241] ? rest_init+0xaa/0xaa [ 1.464241] kernel_init+0xa/0x107 [ 1.464241] ret_from_fork+0x35/0x40 [ 1.464241] Modules linked in: [ 1.464241] CR2: 000000000000004e [ 1.464241] ---[ end trace 0927d2ba8b8032b5 ]--- Cc: Joerg Roedel Cc: Lu Baolu Cc: David Woodhouse Cc: stable@vger.kernel.org # v5.3+ Cc: iommu@lists.linux-foundation.org Fixes: ae23bfb68f28 ("iommu/vt-d: Detach domain before using a private on= e") Signed-off-by: Jerry Snitselaar --- drivers/iommu/intel-iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 0c8d81f56a30..e42a09794fa2 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -5163,7 +5163,8 @@ static void dmar_remove_one_dev_info(struct device = *dev) =20 spin_lock_irqsave(&device_domain_lock, flags); info =3D dev->archdata.iommu; - if (info) + if (info && info !=3D DEFER_DEVICE_DOMAIN_INFO + && info !=3D DUMMY_DEVICE_DOMAIN_INFO) __dmar_remove_one_dev_info(info); spin_unlock_irqrestore(&device_domain_lock, flags); } --=20 2.24.0