From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754781AbbJ0WIe (ORCPT ); Tue, 27 Oct 2015 18:08:34 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:34878 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932227AbbJ0Va5 (ORCPT ); Tue, 27 Oct 2015 17:30:57 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Marek Majtyka , Marc Zyngier , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 33/86] arm: KVM: Fix incorrect device to IPA mapping Date: Tue, 27 Oct 2015 14:29:33 -0700 Message-Id: <1445981426-19727-34-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1445981426-19727-1-git-send-email-kamal@canonical.com> References: <1445981426-19727-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt9 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Marek Majtyka commit ca09f02f122b2ecb0f5ddfc5fd47b29ed657d4fd upstream. A critical bug has been found in device memory stage1 translation for VMs with more then 4GB of address space. Once vm_pgoff size is smaller then pa (which is true for LPAE case, u32 and u64 respectively) some more significant bits of pa may be lost as a shift operation is performed on u32 and later cast onto u64. Example: vm_pgoff(u32)=0x00210030, PAGE_SHIFT=12 expected pa(u64): 0x0000002010030000 produced pa(u64): 0x0000000010030000 The fix is to change the order of operations (casting first onto phys_addr_t and then shifting). Reviewed-by: Marc Zyngier [maz: fixed changelog and patch formatting] Signed-off-by: Marek Majtyka Signed-off-by: Marc Zyngier Signed-off-by: Kamal Mostafa --- arch/arm/kvm/mmu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 9ec6dfe..0512ed4 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1439,8 +1439,10 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, if (vma->vm_flags & VM_PFNMAP) { gpa_t gpa = mem->guest_phys_addr + (vm_start - mem->userspace_addr); - phys_addr_t pa = (vma->vm_pgoff << PAGE_SHIFT) + - vm_start - vma->vm_start; + phys_addr_t pa; + + pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; + pa += vm_start - vma->vm_start; ret = kvm_phys_addr_ioremap(kvm, gpa, pa, vm_end - vm_start, -- 1.9.1