CVE-2022-49895: cxl/region: Fix decoder allocation crash

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-05-01 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: cxl/region: Fix decoder allocation crash When an intermediate port's decoders have been exhausted by existing regions, and creating a new region with the port in question in it's hierarchical path is attempted, cxl_port_attach_region() fails to find a port decoder (as would be expected), and drops into the failure / cleanup path. However, during cleanup of the region reference, a sanity check attempts to dereference the decoder, which in the above case didn't exist. This causes a NULL pointer dereference BUG. To fix this, refactor the decoder allocation and de-allocation into helper routines, and in this 'free' routine, check that the decoder, @cxld, is valid before attempting any operations on it.

Affected products

Linux kernel: from 6.0 before 6.0.8; 6.1-rc1, 6.1-rc2, 6.1-rc3 — fixed in 6.0.8

How to fix

Upgrade to a fixed version: Linux kernel 6.0.8. Check the vendor advisory for mitigations.

References

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