CVE-2026-97963

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

net: stmmac: initialize ptp lock at probe time

priv->ptp lock is only initialized in stmmac ptp register(), which runs during stmmac open(). However, the lock is also used while the interface is down and has never been opened: tc taprio configure() invokes the PTP gettime64() callback to compute the EST base time when offloading a TAPRIO schedule, and stmmac get time() takes priv->ptp lock. Using an uninitialized rwlock is undefined behaviour. Move the rwlock init() to stmmac dvr probe(), together with the other private locks, so that ptp lock is always valid regardless of the interface state.