From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:41365 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752077AbcAEP3q (ORCPT ); Tue, 5 Jan 2016 10:29:46 -0500 From: Jiri Slaby To: stable@vger.kernel.org Cc: Marek Szyprowski , Russell King , Jiri Slaby Subject: [patch added to the 3.12 stable tree] ARM: 8426/1: dma-mapping: add missing range check in dma_mmap() Date: Tue, 5 Jan 2016 16:28:23 +0100 Message-Id: <1452007726-3747-22-git-send-email-jslaby@suse.cz> In-Reply-To: <1452007726-3747-1-git-send-email-jslaby@suse.cz> References: <1452007726-3747-1-git-send-email-jslaby@suse.cz> Sender: stable-owner@vger.kernel.org List-ID: From: Marek Szyprowski This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== 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: Jiri Slaby --- 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 79cff8fdbaf3..f817f3064d67 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1378,12 +1378,17 @@ 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) { -- 2.6.4