CVE-2024-26665 tunnels: fix out of bounds access when building IPv6 PMTU error

In the Linux kernel, the following vulnerability has been resolved: tunnels: fix out of bounds access when building IPv6 PMTU error If the ICMPv6 error is built from a non-linear skb we get the following splat, BUG: KASAN: slab-out-of-bounds in docsum+0x220/0x240 Read of size 4 at addr...