sanitize_speculative_path(struct bpf_verifier_env *env,
			  const struct bpf_insn *insn,
			  u32 next_idx, u32 curr_idx)
{
	struct bpf_verifier_state *branch;
	struct bpf_reg_state *regs;

	branch = push_stack(env, next_idx, curr_idx, true);
	if (branch && insn) {
		regs = branch->frame[branch->curframe]->regs;
		if (BPF_SRC(insn->code) == BPF_K) {
			mark_reg_unknown(env, regs, insn->dst_reg);
		} else if (BPF_SRC(insn->code) == BPF_X) {
			mark_reg_unknown(env, regs, insn->dst_reg);
			mark_reg_unknown(env, regs, insn->src_reg);
		}
	}
	return branch;
}
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.