iommu/dma: Catch scatterlist length overflows

It is possible, when a very large mapping uses only one
scatterlist, that padding overflows scatterlist's length field.
This results in:
 1) silently wrapping the value
 2) smaller than desired mappings produced by iommu_map_sg
 3) leaving mapped bytes in memory (no iommu_unmap)

Address this issue by adding overflow detection for scatterlist
length field.

Fixes: 809eac54cdd6 ("iommu/dma: Implement scatterlist segment merging")
Cc: stable@vger.kernel.org
Assisted-by: LLM
Signed-off-by: Krzysztof Karas <krzysztof.karas@intel.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Sebastian Brzezinka <sebastian.brzezinka@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

0 files changed, 0 insertions, 0 deletions