CVE-2024-42224: net: dsa: mv88e6xxx: Correct check for empty list

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-07-30 · updated 2026-08-04
Weakness: CWE-754

Description

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mv88e6xxx: Correct check for empty list Since commit a3c53be55c95 ("net: dsa: mv88e6xxx: Support multiple MDIO busses") mv88e6xxx_default_mdio_bus() has checked that the return value of list_first_entry() is non-NULL. This appears to be intended to guard against the list chip->mdios being empty. However, it is not the correct check as the implementation of list_first_entry is not designed to return NULL for empty lists. Instead, use list_first_entry_or_null() which does return NULL if the list is empty. Flagged by Smatch. Compile tested only.

Affected products

Linux kernel: from 4.11 before 4.19.318; from 4.20 before 5.4.280; from 5.5 before 5.10.222; from 5.11 before 5.15.163; from 5.16 before 6.1.98; from 6.2 before 6.6.39 — fixed in 4.19.318, 5.10.222, 5.15.163, 5.4.280, 6.1.98, 6.6.39

How to fix

Upgrade to a fixed version: Linux kernel 4.19.318, 5.10.222, 5.15.163, 5.4.280. Check the vendor advisory for mitigations.

References

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