mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 21:24:00 +08:00
iommu/vt-d: Use bounce buffer for untrusted devices
The Intel VT-d hardware uses paging for DMA remapping. The minimum mapped window is a page size. The device drivers may map buffers not filling the whole IOMMU window. This allows the device to access to possibly unrelated memory and a malicious device could exploit this to perform DMA attacks. To address this, the Intel IOMMU driver will use bounce pages for those buffers which don't fill whole IOMMU pages. Cc: Ashok Raj <ashok.raj@intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Xu Pengfei <pengfei.xu@intel.com> Tested-by: Mika Westerberg <mika.westerberg@intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
parent
3b53034c26
commit
cfb94a372f
@ -41,9 +41,11 @@
|
||||
#include <linux/dma-direct.h>
|
||||
#include <linux/crash_dump.h>
|
||||
#include <linux/numa.h>
|
||||
#include <linux/swiotlb.h>
|
||||
#include <asm/irq_remapping.h>
|
||||
#include <asm/cacheflush.h>
|
||||
#include <asm/iommu.h>
|
||||
#include <trace/events/intel_iommu.h>
|
||||
|
||||
#include "irq_remapping.h"
|
||||
#include "intel-pasid.h"
|
||||
@ -344,6 +346,8 @@ static int domain_detach_iommu(struct dmar_domain *domain,
|
||||
static bool device_is_rmrr_locked(struct device *dev);
|
||||
static int intel_iommu_attach_device(struct iommu_domain *domain,
|
||||
struct device *dev);
|
||||
static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
|
||||
dma_addr_t iova);
|
||||
|
||||
#ifdef CONFIG_INTEL_IOMMU_DEFAULT_ON
|
||||
int dmar_disabled = 0;
|
||||
@ -3754,6 +3758,252 @@ static const struct dma_map_ops intel_dma_ops = {
|
||||
.dma_supported = dma_direct_supported,
|
||||
};
|
||||
|
||||
static void
|
||||
bounce_sync_single(struct device *dev, dma_addr_t addr, size_t size,
|
||||
enum dma_data_direction dir, enum dma_sync_target target)
|
||||
{
|
||||
struct dmar_domain *domain;
|
||||
phys_addr_t tlb_addr;
|
||||
|
||||
domain = find_domain(dev);
|
||||
if (WARN_ON(!domain))
|
||||
return;
|
||||
|
||||
tlb_addr = intel_iommu_iova_to_phys(&domain->domain, addr);
|
||||
if (is_swiotlb_buffer(tlb_addr))
|
||||
swiotlb_tbl_sync_single(dev, tlb_addr, size, dir, target);
|
||||
}
|
||||
|
||||
static dma_addr_t
|
||||
bounce_map_single(struct device *dev, phys_addr_t paddr, size_t size,
|
||||
enum dma_data_direction dir, unsigned long attrs,
|
||||
u64 dma_mask)
|
||||
{
|
||||
size_t aligned_size = ALIGN(size, VTD_PAGE_SIZE);
|
||||
struct dmar_domain *domain;
|
||||
struct intel_iommu *iommu;
|
||||
unsigned long iova_pfn;
|
||||
unsigned long nrpages;
|
||||
phys_addr_t tlb_addr;
|
||||
int prot = 0;
|
||||
int ret;
|
||||
|
||||
domain = find_domain(dev);
|
||||
if (WARN_ON(dir == DMA_NONE || !domain))
|
||||
return DMA_MAPPING_ERROR;
|
||||
|
||||
iommu = domain_get_iommu(domain);
|
||||
if (WARN_ON(!iommu))
|
||||
return DMA_MAPPING_ERROR;
|
||||
|
||||
nrpages = aligned_nrpages(0, size);
|
||||
iova_pfn = intel_alloc_iova(dev, domain,
|
||||
dma_to_mm_pfn(nrpages), dma_mask);
|
||||
if (!iova_pfn)
|
||||
return DMA_MAPPING_ERROR;
|
||||
|
||||
/*
|
||||
* Check if DMAR supports zero-length reads on write only
|
||||
* mappings..
|
||||
*/
|
||||
if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL ||
|
||||
!cap_zlr(iommu->cap))
|
||||
prot |= DMA_PTE_READ;
|
||||
if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
|
||||
prot |= DMA_PTE_WRITE;
|
||||
|
||||
/*
|
||||
* If both the physical buffer start address and size are
|
||||
* page aligned, we don't need to use a bounce page.
|
||||
*/
|
||||
if (!IS_ALIGNED(paddr | size, VTD_PAGE_SIZE)) {
|
||||
tlb_addr = swiotlb_tbl_map_single(dev,
|
||||
__phys_to_dma(dev, io_tlb_start),
|
||||
paddr, size, aligned_size, dir, attrs);
|
||||
if (tlb_addr == DMA_MAPPING_ERROR) {
|
||||
goto swiotlb_error;
|
||||
} else {
|
||||
/* Cleanup the padding area. */
|
||||
void *padding_start = phys_to_virt(tlb_addr);
|
||||
size_t padding_size = aligned_size;
|
||||
|
||||
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
|
||||
(dir == DMA_TO_DEVICE ||
|
||||
dir == DMA_BIDIRECTIONAL)) {
|
||||
padding_start += size;
|
||||
padding_size -= size;
|
||||
}
|
||||
|
||||
memset(padding_start, 0, padding_size);
|
||||
}
|
||||
} else {
|
||||
tlb_addr = paddr;
|
||||
}
|
||||
|
||||
ret = domain_pfn_mapping(domain, mm_to_dma_pfn(iova_pfn),
|
||||
tlb_addr >> VTD_PAGE_SHIFT, nrpages, prot);
|
||||
if (ret)
|
||||
goto mapping_error;
|
||||
|
||||
trace_bounce_map_single(dev, iova_pfn << PAGE_SHIFT, paddr, size);
|
||||
|
||||
return (phys_addr_t)iova_pfn << PAGE_SHIFT;
|
||||
|
||||
mapping_error:
|
||||
if (is_swiotlb_buffer(tlb_addr))
|
||||
swiotlb_tbl_unmap_single(dev, tlb_addr, size,
|
||||
aligned_size, dir, attrs);
|
||||
swiotlb_error:
|
||||
free_iova_fast(&domain->iovad, iova_pfn, dma_to_mm_pfn(nrpages));
|
||||
dev_err(dev, "Device bounce map: %zx@%llx dir %d --- failed\n",
|
||||
size, (unsigned long long)paddr, dir);
|
||||
|
||||
return DMA_MAPPING_ERROR;
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_unmap_single(struct device *dev, dma_addr_t dev_addr, size_t size,
|
||||
enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
size_t aligned_size = ALIGN(size, VTD_PAGE_SIZE);
|
||||
struct dmar_domain *domain;
|
||||
phys_addr_t tlb_addr;
|
||||
|
||||
domain = find_domain(dev);
|
||||
if (WARN_ON(!domain))
|
||||
return;
|
||||
|
||||
tlb_addr = intel_iommu_iova_to_phys(&domain->domain, dev_addr);
|
||||
if (WARN_ON(!tlb_addr))
|
||||
return;
|
||||
|
||||
intel_unmap(dev, dev_addr, size);
|
||||
if (is_swiotlb_buffer(tlb_addr))
|
||||
swiotlb_tbl_unmap_single(dev, tlb_addr, size,
|
||||
aligned_size, dir, attrs);
|
||||
|
||||
trace_bounce_unmap_single(dev, dev_addr, size);
|
||||
}
|
||||
|
||||
static dma_addr_t
|
||||
bounce_map_page(struct device *dev, struct page *page, unsigned long offset,
|
||||
size_t size, enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
return bounce_map_single(dev, page_to_phys(page) + offset,
|
||||
size, dir, attrs, *dev->dma_mask);
|
||||
}
|
||||
|
||||
static dma_addr_t
|
||||
bounce_map_resource(struct device *dev, phys_addr_t phys_addr, size_t size,
|
||||
enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
return bounce_map_single(dev, phys_addr, size,
|
||||
dir, attrs, *dev->dma_mask);
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_unmap_page(struct device *dev, dma_addr_t dev_addr, size_t size,
|
||||
enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
bounce_unmap_single(dev, dev_addr, size, dir, attrs);
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_unmap_resource(struct device *dev, dma_addr_t dev_addr, size_t size,
|
||||
enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
bounce_unmap_single(dev, dev_addr, size, dir, attrs);
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_unmap_sg(struct device *dev, struct scatterlist *sglist, int nelems,
|
||||
enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
struct scatterlist *sg;
|
||||
int i;
|
||||
|
||||
for_each_sg(sglist, sg, nelems, i)
|
||||
bounce_unmap_page(dev, sg->dma_address,
|
||||
sg_dma_len(sg), dir, attrs);
|
||||
}
|
||||
|
||||
static int
|
||||
bounce_map_sg(struct device *dev, struct scatterlist *sglist, int nelems,
|
||||
enum dma_data_direction dir, unsigned long attrs)
|
||||
{
|
||||
int i;
|
||||
struct scatterlist *sg;
|
||||
|
||||
for_each_sg(sglist, sg, nelems, i) {
|
||||
sg->dma_address = bounce_map_page(dev, sg_page(sg),
|
||||
sg->offset, sg->length,
|
||||
dir, attrs);
|
||||
if (sg->dma_address == DMA_MAPPING_ERROR)
|
||||
goto out_unmap;
|
||||
sg_dma_len(sg) = sg->length;
|
||||
}
|
||||
|
||||
return nelems;
|
||||
|
||||
out_unmap:
|
||||
bounce_unmap_sg(dev, sglist, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
|
||||
size_t size, enum dma_data_direction dir)
|
||||
{
|
||||
bounce_sync_single(dev, addr, size, dir, SYNC_FOR_CPU);
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_sync_single_for_device(struct device *dev, dma_addr_t addr,
|
||||
size_t size, enum dma_data_direction dir)
|
||||
{
|
||||
bounce_sync_single(dev, addr, size, dir, SYNC_FOR_DEVICE);
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist,
|
||||
int nelems, enum dma_data_direction dir)
|
||||
{
|
||||
struct scatterlist *sg;
|
||||
int i;
|
||||
|
||||
for_each_sg(sglist, sg, nelems, i)
|
||||
bounce_sync_single(dev, sg_dma_address(sg),
|
||||
sg_dma_len(sg), dir, SYNC_FOR_CPU);
|
||||
}
|
||||
|
||||
static void
|
||||
bounce_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
|
||||
int nelems, enum dma_data_direction dir)
|
||||
{
|
||||
struct scatterlist *sg;
|
||||
int i;
|
||||
|
||||
for_each_sg(sglist, sg, nelems, i)
|
||||
bounce_sync_single(dev, sg_dma_address(sg),
|
||||
sg_dma_len(sg), dir, SYNC_FOR_DEVICE);
|
||||
}
|
||||
|
||||
static const struct dma_map_ops bounce_dma_ops = {
|
||||
.alloc = intel_alloc_coherent,
|
||||
.free = intel_free_coherent,
|
||||
.map_sg = bounce_map_sg,
|
||||
.unmap_sg = bounce_unmap_sg,
|
||||
.map_page = bounce_map_page,
|
||||
.unmap_page = bounce_unmap_page,
|
||||
.sync_single_for_cpu = bounce_sync_single_for_cpu,
|
||||
.sync_single_for_device = bounce_sync_single_for_device,
|
||||
.sync_sg_for_cpu = bounce_sync_sg_for_cpu,
|
||||
.sync_sg_for_device = bounce_sync_sg_for_device,
|
||||
.map_resource = bounce_map_resource,
|
||||
.unmap_resource = bounce_unmap_resource,
|
||||
.dma_supported = dma_direct_supported,
|
||||
};
|
||||
|
||||
static inline int iommu_domain_cache_init(void)
|
||||
{
|
||||
int ret = 0;
|
||||
@ -5325,6 +5575,11 @@ static int intel_iommu_add_device(struct device *dev)
|
||||
}
|
||||
}
|
||||
|
||||
if (device_needs_bounce(dev)) {
|
||||
dev_info(dev, "Use Intel IOMMU bounce page dma_ops\n");
|
||||
set_dma_ops(dev, &bounce_dma_ops);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -5342,6 +5597,9 @@ static void intel_iommu_remove_device(struct device *dev)
|
||||
iommu_group_remove_device(dev);
|
||||
|
||||
iommu_device_unlink(&iommu->iommu, dev);
|
||||
|
||||
if (device_needs_bounce(dev))
|
||||
set_dma_ops(dev, NULL);
|
||||
}
|
||||
|
||||
static void intel_iommu_get_resv_regions(struct device *device,
|
||||
|
Loading…
Reference in New Issue
Block a user