6.12-stable review patch. If anyone has any objections, please let me know.
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From: Balbir Singh balbirs@nvidia.com
commit 12f78021973ae422564b234136c702a305932d73 upstream.
UBSan caught a bug with IOMMU SVA domains, where the reported exponent value in __arm_smmu_tlb_inv_range() was >= 64. __arm_smmu_tlb_inv_range() uses the domain's pgsize_bitmap to compute the number of pages to invalidate and the invalidation range. Currently arm_smmu_sva_domain_alloc() does not setup the iommu domain's pgsize_bitmap. This leads to __ffs() on the value returning 64 and that leads to undefined behaviour w.r.t. shift operations
Fix this by initializing the iommu_domain's pgsize_bitmap to PAGE_SIZE. Effectively the code needs to use the smallest page size for invalidation
Cc: stable@vger.kernel.org Fixes: eb6c97647be2 ("iommu/arm-smmu-v3: Avoid constructing invalid range commands") Suggested-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Balbir Singh balbirs@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
Cc: Jean-Philippe Brucker jean-philippe@linaro.org Cc: Will Deacon will@kernel.org Cc: Robin Murphy robin.murphy@arm.com Cc: Joerg Roedel joro@8bytes.org Cc: Jason Gunthorpe jgg@ziepe.ca Reviewed-by: Jason Gunthorpe jgg@nvidia.com Link: https://lore.kernel.org/r/20250412002354.3071449-1-balbirs@nvidia.com Signed-off-by: Will Deacon will@kernel.org --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c @@ -397,6 +397,12 @@ struct iommu_domain *arm_smmu_sva_domain return ERR_CAST(smmu_domain); smmu_domain->domain.type = IOMMU_DOMAIN_SVA; smmu_domain->domain.ops = &arm_smmu_sva_domain_ops; + + /* + * Choose page_size as the leaf page size for invalidation when + * ARM_SMMU_FEAT_RANGE_INV is present + */ + smmu_domain->domain.pgsize_bitmap = PAGE_SIZE; smmu_domain->smmu = smmu;
ret = xa_alloc(&arm_smmu_asid_xa, &asid, smmu_domain,