6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jason Gunthorpe jgg@nvidia.com
[ Upstream commit 6093cd582f8e027117a8d4ad5d129a1aacdc53d2 ]
These three implementations of map_pages() all succeed if a mapping is requested with no read or write. Since they return back to __iommu_map() leaving the mapped output as 0 it triggers an infinite loop. Therefore nothing is using no-access protection bits.
Further, VFIO and iommufd rely on iommu_iova_to_phys() to get back PFNs stored by map, if iommu_map() succeeds but iommu_iova_to_phys() fails that will create serious bugs.
Thus remove this never used "nothing to do" concept and just fail map immediately.
Fixes: e5fc9753b1a8 ("iommu/io-pgtable: Add ARMv7 short descriptor support") Fixes: e1d3c0fd701d ("iommu: add ARM LPAE page table allocator") Fixes: 745ef1092bcf ("iommu/io-pgtable: Move Apple DART support to its own file") Signed-off-by: Jason Gunthorpe jgg@nvidia.com Acked-by: Will Deacon will@kernel.org Reviewed-by: Kevin Tian kevin.tian@intel.com Link: https://lore.kernel.org/r/2-v1-1211e1294c27+4b1-iommu_no_prot_jgg@nvidia.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/io-pgtable-arm-v7s.c | 3 +-- drivers/iommu/io-pgtable-arm.c | 3 +-- drivers/iommu/io-pgtable-dart.c | 3 +-- 3 files changed, 3 insertions(+), 6 deletions(-)
diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c index 75f244a3e12df..06ffc683b28fe 100644 --- a/drivers/iommu/io-pgtable-arm-v7s.c +++ b/drivers/iommu/io-pgtable-arm-v7s.c @@ -552,9 +552,8 @@ static int arm_v7s_map_pages(struct io_pgtable_ops *ops, unsigned long iova, paddr >= (1ULL << data->iop.cfg.oas))) return -ERANGE;
- /* If no access, then nothing to do */ if (!(prot & (IOMMU_READ | IOMMU_WRITE))) - return 0; + return -EINVAL;
while (pgcount--) { ret = __arm_v7s_map(data, iova, paddr, pgsize, prot, 1, data->pgd, diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index 72dcdd468cf30..934dc97f5df9e 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -480,9 +480,8 @@ static int arm_lpae_map_pages(struct io_pgtable_ops *ops, unsigned long iova, if (WARN_ON(iaext || paddr >> cfg->oas)) return -ERANGE;
- /* If no access, then nothing to do */ if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE))) - return 0; + return -EINVAL;
prot = arm_lpae_prot_to_pte(data, iommu_prot); ret = __arm_lpae_map(data, iova, paddr, pgsize, pgcount, prot, lvl, diff --git a/drivers/iommu/io-pgtable-dart.c b/drivers/iommu/io-pgtable-dart.c index 74b1ef2b96bee..10811e0b773d3 100644 --- a/drivers/iommu/io-pgtable-dart.c +++ b/drivers/iommu/io-pgtable-dart.c @@ -250,9 +250,8 @@ static int dart_map_pages(struct io_pgtable_ops *ops, unsigned long iova, if (WARN_ON(paddr >> cfg->oas)) return -ERANGE;
- /* If no access, then nothing to do */ if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE))) - return 0; + return -EINVAL;
tbl = dart_get_table(data, iova);