+BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
+ u32, mode, u64, flags)
+{
+ u32 len_diff_abs = abs(len_diff);
+ bool shrink = len_diff < 0;
+ int ret = 0;
+
+ if (unlikely(flags || mode))
+ return -EINVAL;
+ if (unlikely(len_diff_abs > 0xfffU))
+ return -EFAULT;
+
+ if (!shrink) {
+ ret = skb_cow(skb, len_diff);
+ if (unlikely(ret < 0))
+ return ret;
+ __skb_push(skb, len_diff_abs);
+ memset(skb->data, 0, len_diff_abs);
+ } else {
+ if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
+ return -ENOMEM;
+ __skb_pull(skb, len_diff_abs);
+ }
+ bpf_compute_data_end_sk_skb(skb);
+ if (tls_sw_has_ctx_rx(skb->sk)) {
+ struct strp_msg *rxm = strp_msg(skb);
+
+ rxm->full_len += len_diff;
+ }
+ return ret;
+}
+
+static const struct bpf_func_proto sk_skb_adjust_room_proto = {
+ .func = sk_skb_adjust_room,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_ANYTHING,
+};
+