Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966338AbdDTGjk (ORCPT ); Thu, 20 Apr 2017 02:39:40 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:46680 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966085AbdDTGj3 (ORCPT ); Thu, 20 Apr 2017 02:39:29 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , Eric Auger , Christoffer Dall , Suzuki K Poulose , Marc Zyngier Subject: [PATCH 3.18 070/124] arm/arm64: KVM: Take mmap_sem in kvm_arch_prepare_memory_region Date: Thu, 20 Apr 2017 08:35:45 +0200 Message-Id: <20170420063559.762360503@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170420063557.021306233@linuxfoundation.org> References: <20170420063557.021306233@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 Content-Length: 1399 Lines: 44 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier commit 72f310481a08db821b614e7b5d00febcc9064b36 upstream. We don't hold the mmap_sem while searching for VMAs (via find_vma), in kvm_arch_prepare_memory_region, which can end up in expected failures. Fixes: commit 8eef91239e57 ("arm/arm64: KVM: map MMIO regions at creation time") Cc: Ard Biesheuvel Cc: Eric Auger Reviewed-by: Christoffer Dall [ Handle dirty page logging failure case ] Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- arch/arm/kvm/mmu.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1407,6 +1407,7 @@ int kvm_arch_prepare_memory_region(struc (KVM_PHYS_SIZE >> PAGE_SHIFT)) return -EFAULT; + down_read(¤t->mm->mmap_sem); /* * A memory region could potentially cover multiple VMAs, and any holes * between them, so iterate over all of them to find out if we can map @@ -1464,6 +1465,8 @@ int kvm_arch_prepare_memory_region(struc else stage2_flush_memslot(kvm, memslot); spin_unlock(&kvm->mmu_lock); + + up_read(¤t->mm->mmap_sem); return ret; }