6.10-stable review patch. If anyone has any objections, please let me know.
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From: Lu Baolu baolu.lu@linux.intel.com
[ Upstream commit c420a2b4e8be06f16f3305472bd25a1dd12059ec ]
Address mask specifies the number of low order bits of the address field that must be masked for the invalidation operation.
Since address bits masked start from bit 12, the max address mask should be MAX_AGAW_PFN_WIDTH, as defined in Table 19 ("Invalidate Descriptor Address Mask Encodings") of the spec.
Limit the max address mask returned from calculate_psi_aligned_address() to MAX_AGAW_PFN_WIDTH to prevent potential integer overflow in the following code:
qi_flush_dev_iotlb(): ... addr |= (1ULL << (VTD_PAGE_SHIFT + mask - 1)) - 1; ...
Fixes: c4d27ffaa8eb ("iommu/vt-d: Add cache tag invalidation helpers") Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Reviewed-by: Kevin Tian kevin.tian@intel.com Link: https://lore.kernel.org/r/20240709152643.28109-2-baolu.lu@linux.intel.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/intel/cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/intel/cache.c b/drivers/iommu/intel/cache.c index e8418cdd8331b..0a3bb38a52890 100644 --- a/drivers/iommu/intel/cache.c +++ b/drivers/iommu/intel/cache.c @@ -245,7 +245,7 @@ static unsigned long calculate_psi_aligned_address(unsigned long start, * shared_bits are all equal in both pfn and end_pfn. */ shared_bits = ~(pfn ^ end_pfn) & ~bitmask; - mask = shared_bits ? __ffs(shared_bits) : BITS_PER_LONG; + mask = shared_bits ? __ffs(shared_bits) : MAX_AGAW_PFN_WIDTH; }
*_pages = aligned_pages;