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=-14.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 CF05EC4346A for ; Mon, 21 Sep 2020 16:52:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A8732076E for ; Mon, 21 Sep 2020 16:52:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600707131; bh=fI2aKDivCX+waYHUpVfEfNfFRJSy3ULPsS5Vk61gPrs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1uBgKp94HjzbOjn6eZBaKM5B4o4UqgR+qsm3QB9ujush8LRnRso0ypcJooEDL1yX1 GNNgya70I8XJKIwmbPte4uB2v858SHVLyyfgMS1Ej689jvnqEYMgSvK5fxLAl+UCwc /5l685DTniTfcp6LtkBcq7NLBMjsrbRYyQQtc1lk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729943AbgIUQwK (ORCPT ); Mon, 21 Sep 2020 12:52:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:57634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729031AbgIUQtf (ORCPT ); Mon, 21 Sep 2020 12:49:35 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 203A920874; Mon, 21 Sep 2020 16:49:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600706974; bh=fI2aKDivCX+waYHUpVfEfNfFRJSy3ULPsS5Vk61gPrs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dvgsazQZNeG20VsKCUvjKk1sSOeDQsbVn17rpPtcZeVNXgJ26BOa/qhEmdx5pzefS 35i/3CGFpEAbMcVw2H3DgBw3ish/+DjEjjfHLCXEOhYUR3Qpx+6Mw93Z4EajDt6Mbh FoV9TbGfa/wdMDAuc1GfKJPM1WgCwmF29TIQ1kvs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Joao Martins , Suravee Suthikulpanit , Joerg Roedel , Sasha Levin Subject: [PATCH 5.4 48/72] iommu/amd: Fix potential @entry null deref Date: Mon, 21 Sep 2020 18:31:27 +0200 Message-Id: <20200921163124.164393341@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200921163121.870386357@linuxfoundation.org> References: <20200921163121.870386357@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joao Martins [ Upstream commit 14c4acc5ed22c21f9821103be7c48efdf9763584 ] After commit 26e495f34107 ("iommu/amd: Restore IRTE.RemapEn bit after programming IRTE"), smatch warns: drivers/iommu/amd/iommu.c:3870 amd_iommu_deactivate_guest_mode() warn: variable dereferenced before check 'entry' (see line 3867) Fix this by moving the @valid assignment to after @entry has been checked for NULL. Fixes: 26e495f34107 ("iommu/amd: Restore IRTE.RemapEn bit after programming IRTE") Reported-by: Dan Carpenter Signed-off-by: Joao Martins Reviewed-by: Suravee Suthikulpanit Cc: Suravee Suthikulpanit Link: https://lore.kernel.org/r/20200910171621.12879-1-joao.m.martins@oracle.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/amd_iommu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index cdafc652d9d1a..fa91d856a43ee 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -4431,12 +4431,14 @@ int amd_iommu_deactivate_guest_mode(void *data) struct amd_ir_data *ir_data = (struct amd_ir_data *)data; struct irte_ga *entry = (struct irte_ga *) ir_data->entry; struct irq_cfg *cfg = ir_data->cfg; - u64 valid = entry->lo.fields_remap.valid; + u64 valid; if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) || !entry || !entry->lo.fields_vapic.guest_mode) return 0; + valid = entry->lo.fields_remap.valid; + entry->lo.val = 0; entry->hi.val = 0; -- 2.25.1