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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6AEAC433F5 for ; Mon, 1 Nov 2021 10:33:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C2D24610CF for ; Mon, 1 Nov 2021 10:33:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232236AbhKAKgB (ORCPT ); Mon, 1 Nov 2021 06:36:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:24477 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232161AbhKAKf4 (ORCPT ); Mon, 1 Nov 2021 06:35:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1635762802; 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: in-reply-to:in-reply-to:references:references; bh=mh/lXvO/DjLUSeyCpSgez/WyU/AXkpH1vth0jy9+/fg=; b=Gp27gZu9UkN/rG3GB+E/NXITgjryz0CL3u2BQG8B3vkEtwW/IakfF23kp1fHjZvzT3Yuee j+DuE9CsEvniqdIlYmOia/H3e9RrAZb/rdllG/xMBcSn1q3UhRsurLDGQxJ2Mst6I6qH18 ZJHFHDUm6JhacMpJbFtHThl36iH+QF0= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-147-uurX3Jq7M5Ss4QQG4OKKnA-1; Mon, 01 Nov 2021 06:33:21 -0400 X-MC-Unique: uurX3Jq7M5Ss4QQG4OKKnA-1 Received: by mail-ed1-f69.google.com with SMTP id y12-20020a056402270c00b003e28de6e995so1676650edd.11 for ; Mon, 01 Nov 2021 03:33:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=mh/lXvO/DjLUSeyCpSgez/WyU/AXkpH1vth0jy9+/fg=; b=Z+ycD4gXtzSyttncce+uDPeA5vwwjkogBl7OM3NlLk1YCdedKTcRiid6nZwBeRawSu OaiFMditEHdrIHDCoL/qxzNoDWcvils6tL2oOo+as7/jXQRQicPSuilOlFxgcD4yrSFF lobYkcnPgyGy+oLd7IdoF+1rssi7TkTaAs/k4aC2b8wFMURwxdRS80sU4qSir6jAJjKG OBaK/sbTAfjnMjKqNz90OMoumEVQPT1QW1rcZRbgurRL0nPNB5cwAH4UF+L/pvtzDHj0 w4ZUaWbTrYvAcesg+8oBdjBS1PeP55SzBrHUWnDFArjYdTHdM4sX2Q76d1+9LISj735/ eruw== X-Gm-Message-State: AOAM5313Qj4ncZXr9VxVavhINvZpbokexNhO8pSvAbHodZjMi3MNc1UJ HIWmNk4Qym7rpq0B7uxLb0nOo9Ad1hfJw04gCXDOwZh6wbzi0GlEzx75WsG1VohUI+YecDQ4Ddw grTDjcVNNSH6icMjVPpMKNJwy X-Received: by 2002:a50:8e05:: with SMTP id 5mr39702747edw.76.1635762800379; Mon, 01 Nov 2021 03:33:20 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw9gnk66lzzUHLALthwE3raOdlZGF410uhbCdfiSGqNONoUSpPMJi4RKxjukoAv0gSOLjBOOg== X-Received: by 2002:a50:8e05:: with SMTP id 5mr39702727edw.76.1635762800215; Mon, 01 Nov 2021 03:33:20 -0700 (PDT) Received: from vitty.brq.redhat.com (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id q17sm6607866ejp.106.2021.11.01.03.33.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Nov 2021 03:33:19 -0700 (PDT) From: Vitaly Kuznetsov To: Sean Christopherson Cc: Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Ajay Garg , Paolo Bonzini , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Dexuan Cui , Arnd Bergmann Subject: Re: [PATCH v2 8/8] KVM: x86: Add checks for reserved-to-zero Hyper-V hypercall fields In-Reply-To: <20211030000800.3065132-9-seanjc@google.com> References: <20211030000800.3065132-1-seanjc@google.com> <20211030000800.3065132-9-seanjc@google.com> Date: Mon, 01 Nov 2021 11:33:18 +0100 Message-ID: <87v91cjhch.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sean Christopherson writes: > Add checks for the three fields in Hyper-V's hypercall params that must > be zero. Per the TLFS, HV_STATUS_INVALID_HYPERCALL_INPUT is returned if > "A reserved bit in the specified hypercall input value is non-zero." > > Note, the TLFS has an off-by-one bug for the last reserved field, which > it defines as being bits 64:60. The same section states "The input field > 64-bit value called a hypercall input value.", i.e. bit 64 doesn't > exist. This version are you looking at? I can't see this issue in 6.0b > > Signed-off-by: Sean Christopherson > --- > arch/x86/kvm/hyperv.c | 5 +++++ > include/asm-generic/hyperv-tlfs.h | 6 ++++++ > 2 files changed, 11 insertions(+) > > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index ad455df850c9..1cdcf3ad5684 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -2228,6 +2228,11 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) > goto hypercall_complete; > } > > + if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) { > + ret = HV_STATUS_INVALID_HYPERCALL_INPUT; > + goto hypercall_complete; > + } > + > if (hc.fast && is_xmm_fast_hypercall(&hc)) { > if (unlikely(hv_vcpu->enforce_cpuid && > !(hv_vcpu->cpuid_cache.features_edx & > diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h > index 1ba8e6da4427..92b9ce5882f8 100644 > --- a/include/asm-generic/hyperv-tlfs.h > +++ b/include/asm-generic/hyperv-tlfs.h > @@ -183,11 +183,17 @@ enum HV_GENERIC_SET_FORMAT { > #define HV_HYPERCALL_FAST_BIT BIT(16) > #define HV_HYPERCALL_VARHEAD_OFFSET 17 > #define HV_HYPERCALL_VARHEAD_MASK GENMASK_ULL(26, 17) > +#define HV_HYPERCALL_RSVD0_MASK GENMASK_ULL(31, 27) > #define HV_HYPERCALL_REP_COMP_OFFSET 32 > #define HV_HYPERCALL_REP_COMP_1 BIT_ULL(32) > #define HV_HYPERCALL_REP_COMP_MASK GENMASK_ULL(43, 32) > +#define HV_HYPERCALL_RSVD1_MASK GENMASK_ULL(47, 44) > #define HV_HYPERCALL_REP_START_OFFSET 48 > #define HV_HYPERCALL_REP_START_MASK GENMASK_ULL(59, 48) > +#define HV_HYPERCALL_RSVD2_MASK GENMASK_ULL(63, 60) > +#define HV_HYPERCALL_RSVD_MASK (HV_HYPERCALL_RSVD0_MASK | \ > + HV_HYPERCALL_RSVD1_MASK | \ > + HV_HYPERCALL_RSVD2_MASK) > > /* hypercall status code */ > #define HV_STATUS_SUCCESS 0 Reviewed-by: Vitaly Kuznetsov -- Vitaly