CVE-2026-80956

In the Linux kernel, the following vulnerability has been resolved: dm-pcache: only hand out initialized cache segments get_cache_segment() scans the segment map up to cache->n_segs, the physical device segment count, but cache_segs_init() only initializes the first cache_info->n_segs segments. A crafted image with cache_info->n_segs smaller than the device count leaves the remaining pcache_cache_segment structs zeroed (segment.data == NULL), and the allocator can hand one to cache_kset_close(), which writes through the returned segment's data pointer with no NULL check. Bound the allocator's search to cache_info->n_segs so only initialized segments are ever returned. A conforming cache sets n_segs equal to the device segment count, so this rejects nothing legitimate.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/2df0fc042e299bae3c0f60ea5cd2af9285658e9f
https://git.kernel.org/stable/c/692037ae1a7cfacc2f0c22c6e034c1dfee0e553f
https://git.kernel.org/stable/c/83e3116283ed2c6a6a1fa662862a4b4d7d2701a2

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:19

Updated : 2026-09-11 20:19

NVD link : CVE-2026-80956

Mitre link : CVE-2026-80956

CVE.ORG link : CVE-2026-80956

JSON object : View

Products Affected

No product.

CWE

No CWE.

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