CVE-2026-63924: kernel: ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo()

Severity: Critical

CVSS Score: 9.8

In the Linux kernel, the following vulnerability has been resolved: ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo() ipv6_hop_jumbo() calls pskb_trim_rcsum(), which can change skb pointers. Let's recompute nh pointer to make sure any change won't mess things up.