Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754223AbbGASmT (ORCPT ); Wed, 1 Jul 2015 14:42:19 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:44977 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753756AbbGASlq (ORCPT ); Wed, 1 Jul 2015 14:41:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Zyngier , Ard Biesheuvel , Christoffer Dall , Shannon Zhao Subject: [PATCH 3.14 23/34] arm/arm64: KVM: fix potential NULL dereference in user_mem_abort() Date: Wed, 1 Jul 2015 11:40:30 -0700 Message-Id: <20150701183956.191307992@linuxfoundation.org> X-Mailer: git-send-email 2.4.4 In-Reply-To: <20150701183955.306219425@linuxfoundation.org> References: <20150701183955.306219425@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1420 Lines: 43 3.14-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: Greg Kroah-Hartman --- arch/arm/kvm/mmu.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -778,6 +778,12 @@ static int user_mem_abort(struct kvm_vcp /* 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/