CVE-2026-43344

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

perf/x86/intel/uncore: Fix die ID init and look up bugs

In snbep_pci2phy_map_init(), in the nr_node_ids > 8 path,

uncore_device_to_die() may return -1 when all CPUs associated

with the UBOX device are offline.

Remove the WARN_ON_ONCE(die_id == -1) check for two reasons:

- The current code breaks out of the loop. This is incorrect because

pci_get_device() does not guarantee iteration in domain or bus order,

so additional UBOX devices may be skipped during the scan.

- Returning -EINVAL is incorrect, since marking offline buses with

die_id == -1 is expected and should not be treated as an error.

Separately, when NUMA is disabled on a NUMA-capable platform,

pcibus_to_node() returns NUMA_NO_NODE, causing uncore_device_to_die()

to return -1 for all PCI devices. As a result,

spr_update_device_location(), used on Intel SPR and EMR, ignores the

corresponding PMON units and does not add them to the RB tree.

Fix thi

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References