CVE-2025-40347: Linux

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: net: enetc: fix the deadlock of enetc_mdio_lock After applying the workaround for err050089, the LS1028A platform experiences RCU stalls on RT kernel. This issue is caused by the recursive acquisition of the read lock enetc_mdio_lock. Here list some of the call stacks identified under the enetc_poll path that may lead to a deadlock: enetc_poll -> enetc_lock_mdio -> enetc_clean_rx_ring OR napi_complete_done -> napi_gro_receive -> enetc_start_xmit -> enetc_lock_mdio -> enetc_map_tx_buffs -> enetc_unlock_mdio -> enetc_unlock_mdio After enetc_poll acquires the read lock, a higher-priority writer attempts to acquire the lock, causing preemption. The writer detects that a read lock is already held and is scheduled out. However, readers under enetc_poll cannot acquire the read lock again because a writer is already waiting, leading to a thread hang. Currently, the deadlock is avoided by adjusting enetc_lock_mdio to prevent recursive lock acquisition.

Affected products

• Linux Linux: from 5.10.24, before 5.11 (fixed in 5.11); from 5.11.7, before 5.12 (fixed in 5.12); from 5.12, before 6.1.175 (fixed in 6.1.175); from 6.2, before 6.6.115 (fixed in 6.6.115); from 6.7, before 6.12.56 (fixed in 6.12.56); from 6.13, before 6.17.6 (fixed in 6.17.6)

Published 2025-12-16. Last modified 2026-07-30.