CVE-2024-35860 bpf: support deferring bpf_link dealloc to after RCU grace period

In the Linux kernel, the following vulnerability has been resolved: bpf: support deferring bpflink dealloc to after RCU grace period BPF link for some program types is passed as a "context" which can be used by those BPF programs to look up additional information. E.g., for multi-kprobes and...

CVE-2024-35860

CVE-2024-35860 : Linux kernel vulnerability in deferring bpf_link deallocation to after RCU grace period. When a bpf_link’s refcnt drops to zero, some active BPF programs could still access the link data via context, risking data access. The patch introduces two deallocation callbacks (synchronou...