From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:34346 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753798AbeAVIyj (ORCPT ); Mon, 22 Jan 2018 03:54:39 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Punit Agrawal , Marc Zyngier , Christoffer Dall Subject: [PATCH 4.14 79/89] KVM: arm/arm64: Check pagesize when allocating a hugepage at Stage 2 Date: Mon, 22 Jan 2018 09:45:59 +0100 Message-Id: <20180122084002.349818588@linuxfoundation.org> In-Reply-To: <20180122083954.683903493@linuxfoundation.org> References: <20180122083954.683903493@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Punit Agrawal commit c507babf10ead4d5c8cca704539b170752a8ac84 upstream. KVM only supports PMD hugepages at stage 2 but doesn't actually check that the provided hugepage memory pagesize is PMD_SIZE before populating stage 2 entries. In cases where the backing hugepage size is smaller than PMD_SIZE (such as when using contiguous hugepages), KVM can end up creating stage 2 mappings that extend beyond the supplied memory. Fix this by checking for the pagesize of userspace vma before creating PMD hugepage at stage 2. Fixes: 66b3923a1a0f77a ("arm64: hugetlb: add support for PTE contiguous bit") Signed-off-by: Punit Agrawal Cc: Marc Zyngier Reviewed-by: Christoffer Dall Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman --- virt/kvm/arm/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1310,7 +1310,7 @@ static int user_mem_abort(struct kvm_vcp return -EFAULT; } - if (is_vm_hugetlb_page(vma) && !logging_active) { + if (vma_kernel_pagesize(vma) == PMD_SIZE && !logging_active) { hugetlb = true; gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT; } else {