CVE-2026-31744: PM: EM: Fix NULL pointer dereference when perf domain ID is not found

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-01 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: PM: EM: Fix NULL pointer dereference when perf domain ID is not found dev_energymodel_nl_get_perf_domains_doit() calls em_perf_domain_get_by_id() but does not check the return value before passing it to __em_nl_get_pd_size(). When a caller supplies a non-existent perf domain ID, em_perf_domain_get_by_id() returns NULL, and __em_nl_get_pd_size() immediately dereferences pd->cpus (struct offset 0x30), causing a NULL pointer dereference. The sister handler dev_energymodel_nl_get_perf_table_doit() already handles this correctly via __em_nl_get_pd_table_id(), which returns NULL and causes the caller to return -EINVAL. Add the same NULL check in the get-perf-domains do handler. [ rjw: Subject and changelog edits ]

Affected products

Linux kernel: from 6.19.1 before 6.19.12; 6.19-rc6, 6.19-rc7, 6.19-rc8, 7.0-rc1, 7.0-rc2, 7.0-rc3 (+4) — fixed in 6.19.12

How to fix

Upgrade to a fixed version: Linux kernel 6.19.12. Check the vendor advisory for mitigations.

References

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