CVE-2026-53240 xfrm: iptfs: fix use-after-free on first_skb in __input_process_payload

In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: fix use-after-free on firstskb in inputprocesspayload inputprocesspayload stores firstskb into xtfs-ranewskb under droplock when starting partial reassembly, then unlocks and breaks out of the processing loop. The...