round16
buffer = kzalloc(round16(L + Tn.len) + round16(n_S.len), gfp);
n_S.data = buffer + round16(L + Tn.len);
buffer = kzalloc(round16(tmp1.len) + round16(derived_key.len), gfp);
derived_key.data = buffer + round16(tmp1.len);
buffer = kzalloc(round16(conn_info.len), gfp);