From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754098AbbLIJjK (ORCPT ); Wed, 9 Dec 2015 04:39:10 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:45028 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753997AbbLIJi7 (ORCPT ); Wed, 9 Dec 2015 04:38:59 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Marek Szyprowski , Russell King , Luis Henriques Subject: [PATCH 3.16.y-ckt 019/126] ARM: 8426/1: dma-mapping: add missing range check in dma_mmap() Date: Wed, 9 Dec 2015 09:36:29 +0000 Message-Id: <1449653896-5236-20-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1449653896-5236-1-git-send-email-luis.henriques@canonical.com> References: <1449653896-5236-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt21 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Marek Szyprowski commit 371f0f085f629fc0f66695f572373ca4445a67ad upstream. dma_mmap() function in IOMMU-based dma-mapping implementation lacked a check for valid range of mmap parameters (offset and buffer size), what might have caused access beyond the allocated buffer. This patch fixes this issue. Signed-off-by: Marek Szyprowski Signed-off-by: Russell King Signed-off-by: Luis Henriques --- arch/arm/mm/dma-mapping.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 0e09af35f69a..59336561d747 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1459,12 +1459,17 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma, unsigned long uaddr = vma->vm_start; unsigned long usize = vma->vm_end - vma->vm_start; struct page **pages = __iommu_get_pages(cpu_addr, attrs); + unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long off = vma->vm_pgoff; vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot); if (!pages) return -ENXIO; + if (off >= nr_pages || (usize >> PAGE_SHIFT) > nr_pages - off) + return -ENXIO; + do { int ret = vm_insert_page(vma, uaddr, *pages++); if (ret) {