From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755271AbdDJQuK (ORCPT ); Mon, 10 Apr 2017 12:50:10 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:35856 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754395AbdDJQuI (ORCPT ); Mon, 10 Apr 2017 12:50:08 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoffer Dall , Suzuki K Poulose , Marc Zyngier Subject: [PATCH 4.10 011/110] arm/arm64: KVM: Take mmap_sem in stage2_unmap_vm Date: Mon, 10 Apr 2017 18:42:02 +0200 Message-Id: <20170410164201.868767101@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170410164201.247583164@linuxfoundation.org> References: <20170410164201.247583164@linuxfoundation.org> User-Agent: quilt/0.65 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 4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier commit 90f6e150e44a0dc3883110eeb3ab35d1be42b6bb upstream. We don't hold the mmap_sem while searching for the VMAs when we try to unmap each memslot for a VM. Fix this properly to avoid unexpected results. Fixes: commit 957db105c997 ("arm/arm64: KVM: Introduce stage2_unmap_vm") Reviewed-by: Christoffer Dall Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- arch/arm/kvm/mmu.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -803,6 +803,7 @@ void stage2_unmap_vm(struct kvm *kvm) int idx; idx = srcu_read_lock(&kvm->srcu); + down_read(¤t->mm->mmap_sem); spin_lock(&kvm->mmu_lock); slots = kvm_memslots(kvm); @@ -810,6 +811,7 @@ void stage2_unmap_vm(struct kvm *kvm) stage2_unmap_memslot(kvm, memslot); spin_unlock(&kvm->mmu_lock); + up_read(¤t->mm->mmap_sem); srcu_read_unlock(&kvm->srcu, idx); }