Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753819AbcLFS0q (ORCPT ); Tue, 6 Dec 2016 13:26:46 -0500 Received: from hqemgate15.nvidia.com ([216.228.121.64]:9231 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752090AbcLFS0p (ORCPT ); Tue, 6 Dec 2016 13:26:45 -0500 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 06 Dec 2016 10:26:43 -0800 From: Kirti Wankhede To: , , , CC: , , , Kirti Wankhede Subject: [PATCH v2 2/2] vfio iommu: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages Date: Tue, 6 Dec 2016 23:58:12 +0530 Message-ID: <1481048892-29881-1-git-send-email-kwankhede@nvidia.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1481044425-23920-1-git-send-email-kwankhede@nvidia.com> References: <1481044425-23920-1-git-send-email-kwankhede@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1835 Lines: 49 Passing zero for the size to vfio_find_dma() isn't compatible with matching the start address of an existing vfio_dma. Doing so triggers a corner case. In vfio_find_dma(), when the start address is equal to dma->iova and size is 0, check for the end of search range makes it to take wrong side of RB-tree. That fails the search even though the address is present in mapped dma ranges. In functions pin_pages and unpin_pages, the iova which is being searched is base address of page to be pinned or unpinned. So here size should be set to PAGE_SIZE, as argument to vfio_find_dma(). Signed-off-by: Kirti Wankhede Signed-off-by: Neo Jia --- drivers/vfio/vfio_iommu_type1.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 8e9e94ccb2ff..023fba7b8d5a 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -581,7 +581,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, struct vfio_pfn *vpfn; iova = user_pfn[i] << PAGE_SHIFT; - dma = vfio_find_dma(iommu, iova, 0); + dma = vfio_find_dma(iommu, iova, PAGE_SIZE); if (!dma) { ret = -EINVAL; goto pin_unwind; @@ -622,7 +622,7 @@ pin_unwind: dma_addr_t iova; iova = user_pfn[j] << PAGE_SHIFT; - dma = vfio_find_dma(iommu, iova, 0); + dma = vfio_find_dma(iommu, iova, PAGE_SIZE); vfio_unpin_page_external(dma, iova, do_accounting); phys_pfn[j] = 0; } @@ -659,7 +659,7 @@ static int vfio_iommu_type1_unpin_pages(void *iommu_data, dma_addr_t iova; iova = user_pfn[i] << PAGE_SHIFT; - dma = vfio_find_dma(iommu, iova, 0); + dma = vfio_find_dma(iommu, iova, PAGE_SIZE); if (!dma) goto unpin_exit; vfio_unpin_page_external(dma, iova, do_accounting); -- 2.7.0