Preventing DMA Attacks from Thunderbolt Devices
summary
Shows Linux-facing DMA holes from Thunderbolt: attacks exploit IOMMU/PCIe features (ATS, PASID-like translations, page granularity and lazy/unordered DMA mapping) to read or reuse kernel memory. Presents concrete fixes: disable ATS for untrusted ports (merged in Linux 5.1), per-device screening via a kernel interface, software bounce-page work and proposals to change DMA mapping strictness. Patchset is landed or staged, some hardware/efficiency tradeoffs remain and further testing is ongoing.
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chapters (9)
- 0:00Start
- 1:04Statement
- 2:40DMA attack
- 4:08Before we start ...
- 6:10Device Classification S
- 10:42Fatal ATS
- 16:42Strict Mode
- 24:37Call for action
- 27:39Reference
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