6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jason Gunthorpe jgg@nvidia.com
commit 996dc53ac289b81957aa70d62ccadc6986d26a87 upstream.
This results in passing 0 or just IOMMU_CACHE to iommu_map(). Most of the page table formats don't like this:
amdv1 - -EINVAL armv7s - returns 0, doesn't update mapped arm-lpae - returns 0 doesn't update mapped dart - returns 0, doesn't update mapped VT-D - returns -EINVAL
Unfortunately the three formats that return 0 cause serious problems:
- Returning ret = but not uppdating mapped from domain->map_pages() causes an infinite loop in __iommu_map()
- Not writing ioptes means that VFIO/iommufd have no way to recover them and we will have memory leaks and worse during unmap
Since almost nothing can support this, and it is a useless thing to do, block it early in iommufd.
Cc: stable@kernel.org Fixes: aad37e71d5c4 ("iommufd: IOCTLs for the io_pagetable") Signed-off-by: Jason Gunthorpe jgg@nvidia.com Reviewed-by: Nicolin Chen nicolinc@nvidia.com Reviewed-by: Kevin Tian kevin.tian@intel.com Link: https://lore.kernel.org/r/1-v1-1211e1294c27+4b1-iommu_no_prot_jgg@nvidia.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/iommufd/ioas.c | 8 ++++++++ tools/testing/selftests/iommu/iommufd.c | 6 +++--- 2 files changed, 11 insertions(+), 3 deletions(-)
--- a/drivers/iommu/iommufd/ioas.c +++ b/drivers/iommu/iommufd/ioas.c @@ -213,6 +213,10 @@ int iommufd_ioas_map(struct iommufd_ucmd if (cmd->iova >= ULONG_MAX || cmd->length >= ULONG_MAX) return -EOVERFLOW;
+ if (!(cmd->flags & + (IOMMU_IOAS_MAP_WRITEABLE | IOMMU_IOAS_MAP_READABLE))) + return -EINVAL; + ioas = iommufd_get_ioas(ucmd->ictx, cmd->ioas_id); if (IS_ERR(ioas)) return PTR_ERR(ioas); @@ -253,6 +257,10 @@ int iommufd_ioas_copy(struct iommufd_ucm cmd->dst_iova >= ULONG_MAX) return -EOVERFLOW;
+ if (!(cmd->flags & + (IOMMU_IOAS_MAP_WRITEABLE | IOMMU_IOAS_MAP_READABLE))) + return -EINVAL; + src_ioas = iommufd_get_ioas(ucmd->ictx, cmd->src_ioas_id); if (IS_ERR(src_ioas)) return PTR_ERR(src_ioas); --- a/tools/testing/selftests/iommu/iommufd.c +++ b/tools/testing/selftests/iommu/iommufd.c @@ -531,7 +531,7 @@ TEST_F(iommufd_ioas, copy_area) { struct iommu_ioas_copy copy_cmd = { .size = sizeof(copy_cmd), - .flags = IOMMU_IOAS_MAP_FIXED_IOVA, + .flags = IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE, .dst_ioas_id = self->ioas_id, .src_ioas_id = self->ioas_id, .length = PAGE_SIZE, @@ -1024,7 +1024,7 @@ TEST_F(iommufd_ioas, copy_sweep) { struct iommu_ioas_copy copy_cmd = { .size = sizeof(copy_cmd), - .flags = IOMMU_IOAS_MAP_FIXED_IOVA, + .flags = IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE, .src_ioas_id = self->ioas_id, .dst_iova = MOCK_APERTURE_START, .length = MOCK_PAGE_SIZE, @@ -1314,7 +1314,7 @@ TEST_F(iommufd_mock_domain, user_copy) }; struct iommu_ioas_copy copy_cmd = { .size = sizeof(copy_cmd), - .flags = IOMMU_IOAS_MAP_FIXED_IOVA, + .flags = IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE, .dst_ioas_id = self->ioas_id, .dst_iova = MOCK_APERTURE_START, .length = BUFFER_SIZE,