CVE-2025-40255 net: core: prevent NULL deref in generic_hwtstamp_ioctl_lower()

In the Linux kernel, the following vulnerability has been resolved: net: core: prevent NULL deref in generichwtstampioctllower The ethtool tsconfig Netlink path can trigger a null pointer dereference. A call chain such as: tsconfigpreparedata - devgethwtstampphylib - vlanhwtstampget -...