From nobody Wed Sep 17 05:51:33 2025 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 6E749C04E69 for ; Sat, 29 Jul 2023 01:36:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237239AbjG2Bfs (ORCPT ); Fri, 28 Jul 2023 21:35:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231859AbjG2Bfq (ORCPT ); Fri, 28 Jul 2023 21:35:46 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42CFEE58 for ; Fri, 28 Jul 2023 18:35:45 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-cf4cb742715so2444587276.2 for ; Fri, 28 Jul 2023 18:35:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1690594544; x=1691199344; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=fW+zeLl0d3GvBZwCEAwlFx7jr5U4FE8sODZ9RvpbNnI=; b=ZP2Pl1U+VMG9eIcFe1thgUAFsc8cZjkOgPAjp9pDooSSsuJ2j1IZOS08mKcskS4QYf pOXDSlUcYjELo1efpHRXVtgHB5y7GpDNQUMco/ZqNeHucoPdW3Y+rlVQNz25meZc7hqq 5RNNwpLrak8abUMmSRtmmh8AaDlM9YcDnXUwD6csXaCt+0zy1bTiHq7gwzTzbt28WWc8 8QORYHFn6N2qOJveGmETgH9unGEwC9f/hkfDgCu1zRLzUBiNYnGBWnMbpgxn+2YTbBT0 XSWD6sjGPelyY0Y3oKO6zCWGJa81RfHN/ZhFDivLtF2rE33X8pVMkHMndFMtf1evPZJb odwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690594544; x=1691199344; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=fW+zeLl0d3GvBZwCEAwlFx7jr5U4FE8sODZ9RvpbNnI=; b=FBx7I2BqMujNZxlaIPwKMkusxe6RD31z8eXtMJ43YCsivq4/8UF5khUHoMzCkzI4ES wu1T+MkOKX7M8IvJV7US0MoCMHbg74X9vrPT2Chx7smdSIBZs6uBnYWSuyUpAqfPfCoR SMJOl1BzqWiF85s1nbPKE+Sv/aJzoBh7xt3qgzBS3P28sbSgamhibAe+pfs+fU9FHxKx 8zdetzGK+gZ9wUGrdsptUB/QIoQ7LeabGwLeycPsBh+B/3g9Zag5yzu2ZZpumf/A3pYh U4UDva2VTcuOi9rnxZjgzw6YhtYN9KSeEtEehQUy9kc5UiXXzBTfZL80xvJywZlW1MMo IC9g== X-Gm-Message-State: ABy/qLb7uVATTI3vZGPpmYI3UXeyViKjuTYtW0N9YvAMNErYkCOHS06C OsDHt5SXbEHQAyH7cbSfFbP+fSfdgIU= X-Google-Smtp-Source: APBJJlEMdfy+y58tC/xUBasIf3ZTmatdKbl/uuM/5Z7SlwY7B7FyHVWpyPUm13Npqe1zGQwR8s/AvTfClgo= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a25:2508:0:b0:d05:e080:63c6 with SMTP id l8-20020a252508000000b00d05e08063c6mr18632ybl.9.1690594544514; Fri, 28 Jul 2023 18:35:44 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 28 Jul 2023 18:35:07 -0700 In-Reply-To: <20230729013535.1070024-1-seanjc@google.com> Mime-Version: 1.0 References: <20230729013535.1070024-1-seanjc@google.com> X-Mailer: git-send-email 2.41.0.487.g6d72f3e995-goog Message-ID: <20230729013535.1070024-2-seanjc@google.com> Subject: [PATCH v4 01/29] drm/i915/gvt: Verify pfn is "valid" before dereferencing "struct page" From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini , Zhenyu Wang , Zhi Wang Cc: kvm@vger.kernel.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, Yan Zhao , Yongwei Ma , Ben Gardon Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Check that the pfn found by gfn_to_pfn() is actually backed by "struct page" memory prior to retrieving and dereferencing the page. KVM supports backing guest memory with VM_PFNMAP, VM_IO, etc., and so there is no guarantee the pfn returned by gfn_to_pfn() has an associated "struct page". Fixes: b901b252b6cf ("drm/i915/gvt: Add 2M huge gtt support") Reviewed-by: Yan Zhao Tested-by: Yongwei Ma Signed-off-by: Sean Christopherson Reviewed-by: Zhi Wang --- drivers/gpu/drm/i915/gvt/gtt.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c index 4ec85308379a..58b9b316ae46 100644 --- a/drivers/gpu/drm/i915/gvt/gtt.c +++ b/drivers/gpu/drm/i915/gvt/gtt.c @@ -1183,6 +1183,10 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vg= pu, pfn =3D gfn_to_pfn(vgpu->vfio_device.kvm, ops->get_pfn(entry)); if (is_error_noslot_pfn(pfn)) return -EINVAL; + + if (!pfn_valid(pfn)) + return -EINVAL; + return PageTransHuge(pfn_to_page(pfn)); } =20 --=20 2.41.0.487.g6d72f3e995-goog