Local memory access via unchecked uprobe data

Out-of-bounds access in affected Linux kernel builds allows local users to read or write memory through BPF uprobe_multi data. The uprobe_multi path in kernel/trace/bpf_trace.c uses __get_user on user-space offset and reference-counter arrays without an access_ok bounds check. Low-privileged local access is required; malformed array pointers can expose or alter kernel memory, crash the host, or support privilege escalation.