Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757230AbbEVJ2r (ORCPT ); Fri, 22 May 2015 05:28:47 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:35043 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757090AbbEVI7a (ORCPT ); Fri, 22 May 2015 04:59:30 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Ard Biesheuvel , Christoffer Dall , Shannon Zhao , Luis Henriques Subject: [PATCH 3.16.y-ckt 055/129] arm/arm64: KVM: fix potential NULL dereference in user_mem_abort() Date: Fri, 22 May 2015 09:57:20 +0100 Message-Id: <1432285114-9254-56-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1432285114-9254-1-git-send-email-luis.henriques@canonical.com> References: <1432285114-9254-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1545 Lines: 42 3.16.7-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Ard Biesheuvel commit 37b544087ef3f65ca68465ba39291a07195dac26 upstream. Handle the potential NULL return value of find_vma_intersection() before dereferencing it. Acked-by: Marc Zyngier Signed-off-by: Ard Biesheuvel Signed-off-by: Christoffer Dall Signed-off-by: Shannon Zhao Signed-off-by: Luis Henriques --- arch/arm/kvm/mmu.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 40e52eeaf12f..0258b22bf9d1 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -778,6 +778,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, /* Let's check if we will get back a huge page backed by hugetlbfs */ down_read(¤t->mm->mmap_sem); vma = find_vma_intersection(current->mm, hva, hva + 1); + if (unlikely(!vma)) { + kvm_err("Failed to find VMA for hva 0x%lx\n", hva); + up_read(¤t->mm->mmap_sem); + return -EFAULT; + } + if (is_vm_hugetlb_page(vma)) { hugetlb = true; gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/