CVE-2026-90210 bpf: Fix UAF in bpf_trampoline_multi_attach_free on update failure

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix UAF in bpftrampolinemultiattachfree on update failure When bpftrampolineupdate fails before modifyfentrymulti/ unregisterfentrymulti is called, curimage is unchanged curimage == oldimage and ftrace still calls into it...