From: Kirti Wankhede Date: Tue, 6 Dec 2016 18:28:12 +0000 (+0530) Subject: vfio iommu type1: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2b8bb1d771f736b8b34bf160115aee1b12d29f83;p=linux-beck.git vfio iommu type1: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages 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 Signed-off-by: Alex Williamson --- diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 198cf398427e..9815e45c23c4 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);