Linux Kernel up to 6.0.7 cxl_port_attach_region null pointer dereference

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.0.7. This issue affects the function cxl_port_attach_region. Executing a manipulation can lead to null pointer dereference. This vulnerability is handled as CVE-2022-49895. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.0.7. This vulnerability affects the function cxl_port_attach_region. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. CVE summarizes:

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.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2022-49895 since 05/01/2025. There are known technical details, but no exploit is available.

Upgrading to version 6.0.8 eliminates this vulnerability. Applying the patch c6813b5610ac53af73edd87a660d23a0511faa47/71ee71d7adcba648077997a29a91158d20c40b09 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.0.0
• 6.0.1
• 6.0.2
• 6.0.3
• 6.0.4
• 6.0.5
• 6.0.6
• 6.0.7

License

• open-source

Website

• Vendor: https://www.kernel.org/

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