From patchwork Tue Apr 5 07:29:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 557821 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91B9CC4707F for ; Tue, 5 Apr 2022 08:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245359AbiDEIzO (ORCPT ); Tue, 5 Apr 2022 04:55:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240728AbiDEIc2 (ORCPT ); Tue, 5 Apr 2022 04:32:28 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C0BF7C15B; Tue, 5 Apr 2022 01:24:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1EDB3B81BBF; Tue, 5 Apr 2022 08:24:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 875EDC385A1; Tue, 5 Apr 2022 08:24:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649147087; bh=cznyEpNzsTlaaxDVh7pqUaJlIdL/rp+lo6bpM9NMiN0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J3qe3X4Y1hWaRUREnv2BI+o6u9BJ8duycyPnKFXV8kai+9ktjI0jghEL0WWCsyeBJ ZSC3guTIf8LToUbUGK++nVAxOB2nek2x9yzrk3KLrw2XQQpBlCgrCCoXcXkViisgZh 3PRnKm/b/5LQwf5NxWyNDOQ+WaIrpzQzM+05M8E4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Kuznetsov , Paolo Bonzini Subject: [PATCH 5.17 0996/1126] KVM: x86: Check lapic_in_kernel() before attempting to set a SynIC irq Date: Tue, 5 Apr 2022 09:29:03 +0200 Message-Id: <20220405070436.728445501@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070407.513532867@linuxfoundation.org> References: <20220405070407.513532867@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vitaly Kuznetsov commit 7ec37d1cbe17d8189d9562178d8b29167fe1c31a upstream. When KVM_CAP_HYPERV_SYNIC{,2} is activated, KVM already checks for irqchip_in_kernel() so normally SynIC irqs should never be set. It is, however, possible for a misbehaving VMM to write to SYNIC/STIMER MSRs causing erroneous behavior. The immediate issue being fixed is that kvm_irq_delivery_to_apic() (kvm_irq_delivery_to_apic_fast()) crashes when called with 'irq.shorthand = APIC_DEST_SELF' and 'src == NULL'. Signed-off-by: Vitaly Kuznetsov Message-Id: <20220325132140.25650-2-vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/hyperv.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -446,6 +446,9 @@ static int synic_set_irq(struct kvm_vcpu struct kvm_lapic_irq irq; int ret, vector; + if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm)) + return -EINVAL; + if (sint >= ARRAY_SIZE(synic->sint)) return -EINVAL;