CVE-2026-23139 netfilter: nf_conncount: update last_gc only when GC has been performed

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfconncount: update lastgc only when GC has been performed Currently lastgc is being updated everytime a new connection is tracked, that means that it is updated even if a GC wasn't performed. With a sufficiently high...