Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755739AbdLOJqw (ORCPT ); Fri, 15 Dec 2017 04:46:52 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:33946 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755700AbdLOJqu (ORCPT ); Fri, 15 Dec 2017 04:46:50 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Suzuki K Poulose , Christoffer Dall , Kristina Martsenko , Marc Zyngier Subject: [PATCH 4.4 028/105] arm64: KVM: fix VTTBR_BADDR_MASK BUG_ON off-by-one Date: Fri, 15 Dec 2017 10:44:26 +0100 Message-Id: <20171215092307.309488316@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171215092305.994559179@linuxfoundation.org> References: <20171215092305.994559179@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: 1967 Lines: 53 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kristina Martsenko commit 26aa7b3b1c0fb3f1a6176a0c1847204ef4355693 upstream. VTTBR_BADDR_MASK is used to sanity check the size and alignment of the VTTBR address. It seems to currently be off by one, thereby only allowing up to 47-bit addresses (instead of 48-bit) and also insufficiently checking the alignment. This patch fixes it. As an example, with 4k pages, before this patch we have: PHYS_MASK_SHIFT = 48 VTTBR_X = 37 - 24 = 13 VTTBR_BADDR_SHIFT = 13 - 1 = 12 VTTBR_BADDR_MASK = ((1 << 35) - 1) << 12 = 0x00007ffffffff000 Which is wrong, because the mask doesn't allow bit 47 of the VTTBR address to be set, and only requires the address to be 12-bit (4k) aligned, while it actually needs to be 13-bit (8k) aligned because we concatenate two 4k tables. With this patch, the mask becomes 0x0000ffffffffe000, which is what we want. Fixes: 0369f6a34b9f ("arm64: KVM: EL2 register definitions") Reviewed-by: Suzuki K Poulose Reviewed-by: Christoffer Dall Signed-off-by: Kristina Martsenko Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/kvm_arm.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -164,8 +164,7 @@ #define VTTBR_X (37 - VTCR_EL2_T0SZ_40B) #endif -#define VTTBR_BADDR_SHIFT (VTTBR_X - 1) -#define VTTBR_BADDR_MASK (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) +#define VTTBR_BADDR_MASK (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_X) #define VTTBR_VMID_SHIFT (UL(48)) #define VTTBR_VMID_MASK (UL(0xFF) << VTTBR_VMID_SHIFT)