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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F23B2C433EF for ; Sun, 5 Dec 2021 12:11:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233592AbhLEMOw (ORCPT ); Sun, 5 Dec 2021 07:14:52 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:51994 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233585AbhLEMOv (ORCPT ); Sun, 5 Dec 2021 07:14:51 -0500 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 dfw.source.kernel.org (Postfix) with ESMTPS id 9C4C860FC0 for ; Sun, 5 Dec 2021 12:11:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4521C341C1; Sun, 5 Dec 2021 12:11:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638706284; bh=3Qz9ErM3kgn4WOHUSv+dPjFRwCP6QXI6X0D5qTwGO5A=; h=Subject:To:Cc:From:Date:From; b=vRYAi03a9Ub6ilCnT29mQMhpGXfUwRXOLgD8UU8cT2/OPo9bGIueN5rHQ6Ol4K5Pb l9wrJ8xkO1FxVP5FviWaeGp/5ZPh2hnxAfKdXlZkG+Fp2JTVfVvOBndZYv1qtaRiUH Vm6XVfN0flm4nvxzUWqsiuUSBnaolDxrPSVavoB0= Subject: FAILED: patch "[PATCH] KVM: Disallow user memslot with size that exceeds "unsigned" failed to apply to 4.9-stable tree To: seanjc@google.com, maciej.szmigiero@oracle.com, pbonzini@redhat.com Cc: From: Date: Sun, 05 Dec 2021 13:11:13 +0100 Message-ID: <1638706273100253@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 6b285a5587506bae084cf9a3ed5aa491d623b91b Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 4 Nov 2021 00:25:03 +0000 Subject: [PATCH] KVM: Disallow user memslot with size that exceeds "unsigned long" Reject userspace memslots whose size exceeds the storage capacity of an "unsigned long". KVM's uAPI takes the size as u64 to support large slots on 64-bit hosts, but does not account for the size being truncated on 32-bit hosts in various flows. The access_ok() check on the userspace virtual address in particular casts the size to "unsigned long" and will check the wrong number of bytes. KVM doesn't actually support slots whose size doesn't fit in an "unsigned long", e.g. KVM's internal kvm_memory_slot.npages is an "unsigned long", not a "u64", and misc arch specific code follows that behavior. Fixes: fa3d315a4ce2 ("KVM: Validate userspace_addr of memslot when registered") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Reviewed-by: Maciej S. Szmigiero Message-Id: <20211104002531.1176691-3-seanjc@google.com> Signed-off-by: Paolo Bonzini diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 2104fc29cdd2..6c5083f2eb50 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1689,7 +1689,8 @@ int __kvm_set_memory_region(struct kvm *kvm, id = (u16)mem->slot; /* General sanity checks */ - if (mem->memory_size & (PAGE_SIZE - 1)) + if ((mem->memory_size & (PAGE_SIZE - 1)) || + (mem->memory_size != (unsigned long)mem->memory_size)) return -EINVAL; if (mem->guest_phys_addr & (PAGE_SIZE - 1)) return -EINVAL;