CVE Catalog

CVE-2026-93078

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel, the cxl/features module's cxlctl_set_feature() sizes its output buffer from the user's fwctl_rpc.out_len but never checks it is large enough to hold even the fwctl_rpc_cxl_out header. With out_len == 0, kvzalloc() returns ZERO_SIZE_PTR, which passes the !rpc_out check, and the subsequent rpc_out->size = 0 writes through the poison pointer.

Risk Assessment

A write through the poison pointer can lead to a kernel crash or potential memory corruption. It requires local access to the FWCTL interface.

Recommendation

Update the Linux kernel to a version with the fix. Restrict access to the FWCTL_RPC interface to trusted users.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: cxl/features: Reject Set Features output buffer smaller than the header cxlctl_set_feature() sizes its output buffer from the user's fwctl_rpc.out_len but never checks it is large enough to hold even the fwctl_rpc_cxl_out header. With out_len == 0 , kvzalloc() returns ZERO_SIZE_PTR, which passes the !rpc_out check, the subsequent rpc_out->size = 0 then writes through the poison pointer. Reject requests whose output buffer can't hold the response header, before allocating. The Set Feature reply carries no payload, so the header is all that is required.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS