Description

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.

Weaknesses 2

Affected Products 2

References 3

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

Remediation

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