CVE-2024-53232

In the Linux kernel, the following vulnerability has been resolved:

iommu/s390: Implement blocking domain

This fixes a crash when surprise hot-unplugging a PCI device. This crash happens because during hot-unplug __iommu_group_set_domain_nofail() attaching the default domain fails when the platform no longer recognizes the device as it has already been removed and we end up with a NULL domain pointer and UAF. This is exactly the case referred to in the second comment in __iommu_device_set_domain() and just as stated there if we can instead attach the blocking domain the UAF is prevented as this can handle the already removed device. Implement the blocking domain to use this handling. With this change, the crash is fixed but we still hit a warning attempting to change DMA ownership on a blocked device.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/3be34fa1cdbf180c1a948cfededfdf2cdc497199
• https://git.kernel.org/stable/c/bd89d94f3ea6fdaee983cbc69226a00b9bde6d59
• https://git.kernel.org/stable/c/ecda483339a5151e3ca30d6b82691ef6f1d17912