Description
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix race condition during PASID entry replacement The Intel VT-d PASID table entry is 512 bits (64 bytes). When replacing an active PASID entry (e.g., during domain replacement), the current implementation calculates a new entry on the stack and copies it to the table using a single structure assignment. struct pasid_entry *pte, new_pte; pte = intel_pasid_get_entry(dev, pasid); pasid_pte_config_first_level(iommu, &new_pte, ...); *pte = new_pte; Because the hardware may fetch the 512-bit PASID entry in multiple 128-bit chunks, updating the entire entry while it is active (Present bit set) risks a "torn" read. In this scenario, the IOMMU hardware could observe an inconsistent state — partially new data and partially old data — leading to unpredictable behavior or spurious faults. Fix this by removing the unsafe "replace" helpers and following the "clear-then-update" flow, which ensures the Present bit is cleared and the required invalidation handshake is completed before the new configuration is applied.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
7543ee63e8113aa34b07df3b16b3b9d2c5f73939 to < 4718007870547e1efebbdd6745d9fce58f008fefaffected7543ee63e8113aa34b07df3b16b3b9d2c5f73939 to < 66a7aff480a82b8642b3991fed5fdc9780022157affected7543ee63e8113aa34b07df3b16b3b9d2c5f73939 to < c3b1edea3791fa91ab7032faa90355913ad9451baffected
Linux Linux
Default version status: affected
6.13affected0 to < 6.13unaffected6.18.39 to ≤ 6.18.*unaffected6.19.4 to ≤ 6.19.*unaffected7.0 to ≤ *unaffected