Fix crash in mac_nr when accesing the ue_db and not checking if the rnti is valid, while there fix a potential data race.

Fix data race inside sched_nr when modifying per ue metrics.

srsenb/hdr/stack/mac/nr/sched_nr_ue.h

@@ -77,6 +77,7 @@ public:
 
   // metrics
   mac_ue_metrics_t metrics = {};
+  std::mutex       metrics_mutex;
 
 private:
   bwp_ue_cfg           bwp_cfg;

srsenb/src/stack/mac/nr/mac_nr.cc

@@ -389,9 +389,12 @@ bool mac_nr::handle_uci_data(const uint16_t rnti, const srsran_uci_cfg_nr_t& cfg
   }
 
   // Process CQI
-  if (value.valid) {
+  {
+    srsran::rwlock_read_guard rw_lock(rwmutex);
+    if (ue_db.contains(rnti) && value.valid) {
       ue_db[rnti]->metrics_dl_cqi(cfg_, value.csi->wideband_cri_ri_pmi_cqi.cqi);
     }
+  }
 
   return true;
 }

srsenb/src/stack/mac/nr/sched_nr.cc

@@ -172,6 +172,7 @@ void sched_nr::dl_ack_info(uint16_t rnti, uint32_t cc, uint32_t pid, uint32_t tb
   sched_workers->enqueue_cc_feedback(rnti, cc, [this, pid, tb_idx, ack](ue_carrier& ue_cc) {
     int tbs = ue_cc.harq_ent.dl_ack_info(pid, tb_idx, ack);
     if (tbs >= 0) {
+      std::lock_guard<std::mutex> lock(ue_cc.metrics_mutex);
       if (ack) {
         ue_cc.metrics.tx_brate += tbs;
       } else {

srsenb/src/stack/mac/nr/sched_nr_worker.cc

@@ -375,6 +375,7 @@ void sched_worker_manager::get_metrics_nolocking(mac_metrics_t& metrics)
   for (mac_ue_metrics_t& ue_metric : metrics.ues) {
     if (ue_db.contains(ue_metric.rnti) and ue_db[ue_metric.rnti]->carriers[0] != nullptr) {
       auto& ue_cc         = *ue_db[ue_metric.rnti]->carriers[0];
+      std::lock_guard<std::mutex> lock(ue_cc.metrics_mutex);
       ue_metric.tx_brate  = ue_cc.metrics.tx_brate;
       ue_metric.tx_errors = ue_cc.metrics.tx_errors;
       ue_metric.tx_pkts   = ue_cc.metrics.tx_pkts;