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=-11.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 16620C4742C for ; Sat, 31 Oct 2020 14:07:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BF89C206E3 for ; Sat, 31 Oct 2020 14:07:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YM/5mknq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727746AbgJaOHH (ORCPT ); Sat, 31 Oct 2020 10:07:07 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:35639 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727535AbgJaOHG (ORCPT ); Sat, 31 Oct 2020 10:07:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1604153225; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xMiipHhMwnl5lpPS75itYpq+OfzfMobaQ3Fe/heX+4E=; b=YM/5mknq39hDqAzOlc746qTI7wlyMgquTqPFHzgIJur/p9TIlNC5OQ2emj7t/VycGIAjVM glaV+jPzYt1S+QV7QvIpFc3G0V6ph1knAV4QoaoWnN1i+nmTocxYU6U6cj9UxIud1tjpN0 R+EhAZwbtOp6tgDXJ+hcXp5Xt3eZoEo= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-422-2V0-0rieM7O24fR9kIAq-w-1; Sat, 31 Oct 2020 10:07:03 -0400 X-MC-Unique: 2V0-0rieM7O24fR9kIAq-w-1 Received: by mail-wr1-f71.google.com with SMTP id t17so4054538wrm.13 for ; Sat, 31 Oct 2020 07:07:02 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=xMiipHhMwnl5lpPS75itYpq+OfzfMobaQ3Fe/heX+4E=; b=h491ZzRh3FhJT9ZUD+/JbVjnhleEAIakxWdgkgwuTVxCRJY0DvCD07kjzH1VevUXlq gzGKyNSbcWjZh3A6ouKWkdXJmU9kM9+hE6+75r02+K9pCb2Vf0fwTrd0+C3HPU0On+ij P0curEKoZqTer3El+Erowhgp8nzzJ7+FhW68cZc6+1BnzR0N69vhnWHA+dvGe6ANjHt3 k3KkKAB0UPqSThD7CwOl6beZCX7TM5GUCg/L/uYQcAHUdnkQ8NSlaF2h5xWFzwFepP6S 8i5DZnhuMi7GAJ6QNvXdHLI6t66Y1MeCfCHz2rkHjfqLhv6QyacumUbHb0hcG2cCKQEF Vhog== X-Gm-Message-State: AOAM530gYvVPJkR5q+UjJG09aSd8L+VHg03SbkvUaywgAVowRAn/kRZw qBfgJNWRA0svGiw/B2PooWXvDijjhPni7ze/JeLQ0psbyUkZIeEAfTL1Y1FOF0sVDZ1EQvmbEGZ URkqZY1Qwt4i1 X-Received: by 2002:a5d:63c3:: with SMTP id c3mr9385758wrw.315.1604153221971; Sat, 31 Oct 2020 07:07:01 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzkJpxxa2iscAGu8SNcNjP75DAejMNfb47sfZpoaSDn3Ceet8CtSjjL+8fUI8eGR41Z3xuORA== X-Received: by 2002:a5d:63c3:: with SMTP id c3mr9385742wrw.315.1604153221815; Sat, 31 Oct 2020 07:07:01 -0700 (PDT) Received: from [192.168.178.64] ([151.20.250.56]) by smtp.gmail.com with ESMTPSA id c10sm6473164wrx.13.2020.10.31.07.07.00 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 31 Oct 2020 07:07:01 -0700 (PDT) Subject: Re: [PATCH 2/2] KVM: X86: Fix null pointer reference for KVM_GET_MSRS To: Peter Xu , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Takashi Iwai Cc: Vitaly Kuznetsov , Sean Christopherson , Steffen Dirkwinkel References: <20201025185334.389061-1-peterx@redhat.com> <20201025185334.389061-3-peterx@redhat.com> From: Paolo Bonzini Message-ID: Date: Sat, 31 Oct 2020 15:06:59 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: <20201025185334.389061-3-peterx@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 25/10/20 19:53, Peter Xu wrote: > kvm_msr_ignored_check() could trigger a null pointer reference if ignore_msrs=Y > and report_ignore_msrs=Y when try to fetch an invalid feature msr using the > global KVM_GET_MSRS. Degrade the error report to not rely on vcpu since that > information (index, rip) is not as important as msr index/data after all. > > Fixes: 12bc2132b15e0a96 > Reported-by: Steffen Dirkwinkel > Signed-off-by: Peter Xu > --- > arch/x86/kvm/x86.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index ce856e0ece84..5993fbd6d2c5 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -259,8 +259,8 @@ static int kvm_msr_ignored_check(struct kvm_vcpu *vcpu, u32 msr, > > if (ignore_msrs) { > if (report_ignored_msrs) > - vcpu_unimpl(vcpu, "ignored %s: 0x%x data 0x%llx\n", > - op, msr, data); > + kvm_pr_unimpl("ignored %s: 0x%x data 0x%llx\n", > + op, msr, data); > /* Mask the error */ > return 0; > } else { > I committed Takashi Iwai's very similar patch. Please resend 1/2 with reviewer comments addressed, thanks! Paolo