rrc: check pool buffer allocation and handle error

srsue/src/upper/rrc.cc

@@ -1529,10 +1529,13 @@ byte_buffer_t* rrc::byte_align_and_pack(byte_buffer_t *pdu)
     pdcp_buf = pool_allocate;
   }
 
+  if (pdcp_buf != NULL) {
     srslte_bit_pack_vector(bit_buf.msg, pdcp_buf->msg, bit_buf.N_bits);
     pdcp_buf->N_bytes = bit_buf.N_bits / 8;
     pdcp_buf->set_timestamp();
-
+  } else {
+    rrc_log->error("Fatal Error: Couldn't allocate PDU in byte_align_and_pack().\n");
+  }
   return pdcp_buf;
 }
 
@@ -1540,7 +1543,7 @@ void rrc::send_ul_ccch_msg(byte_buffer_t *pdu)
 {
   liblte_rrc_pack_ul_ccch_msg(&ul_ccch_msg, (LIBLTE_BIT_MSG_STRUCT *) &bit_buf);
   pdu = byte_align_and_pack(pdu);
-
+  if (pdu) {
     // Set UE contention resolution ID in MAC
     uint64_t uecri = 0;
     uint8_t *ue_cri_ptr = (uint8_t *) &uecri;
@@ -1555,16 +1558,18 @@ void rrc::send_ul_ccch_msg(byte_buffer_t *pdu)
     rrc_log->info("Sending %s\n", liblte_rrc_ul_ccch_msg_type_text[ul_ccch_msg.msg_type]);
     pdcp->write_sdu(RB_ID_SRB0, pdu);
   }
+}
 
 void rrc::send_ul_dcch_msg(byte_buffer_t *pdu)
 {
   liblte_rrc_pack_ul_dcch_msg(&ul_dcch_msg, (LIBLTE_BIT_MSG_STRUCT *) &bit_buf);
 
   pdu = byte_align_and_pack(pdu);
-
+  if (pdu) {
     rrc_log->info("Sending %s\n", liblte_rrc_ul_dcch_msg_type_text[ul_dcch_msg.msg_type]);
     pdcp->write_sdu(RB_ID_SRB1, pdu);
   }
+}
 
 void rrc::write_sdu(uint32_t lcid, byte_buffer_t *sdu) {