From 28dc194e2ff4d63f501eaf5d8c863b1089a15a74 Mon Sep 17 00:00:00 2001
From: Ismael Gomez <ismagom@gmail.com>
Date: Wed, 25 Apr 2018 19:46:10 +0200
Subject: [PATCH] Fix UE blocking on Reestablishment when Overflow

---
 srsue/src/phy/phch_recv.cc | 12 +++++++-----
 srsue/src/upper/nas.cc     |  1 +
 srsue/src/upper/rrc.cc     | 28 ++++++++++++----------------
 3 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/srsue/src/phy/phch_recv.cc b/srsue/src/phy/phch_recv.cc
index 780f2c72a..3d8d7f3cf 100644
--- a/srsue/src/phy/phch_recv.cc
+++ b/srsue/src/phy/phch_recv.cc
@@ -257,19 +257,21 @@ phy_interface_rrc::cell_search_ret_t phch_recv::cell_search(phy_interface_rrc::p
 bool phch_recv::cell_select(phy_interface_rrc::phy_cell_t *new_cell) {
   pthread_mutex_lock(&rrc_mutex);
 
+  bool ret = false;
+  int cnt = 0;
+
   // Move state to IDLE
   if (!new_cell) {
     Info("Cell Select: Starting cell resynchronization\n");
   } else {
     if (!srslte_cell_isvalid(&cell)) {
       log_h->error("Cell Select: Invalid cell. ID=%d, PRB=%d, ports=%d\n", cell.id, cell.nof_prb, cell.nof_ports);
-      return false;
+      goto unlock;
     }
     Info("Cell Select: Starting cell selection for PCI=%d, EARFCN=%d\n", new_cell->cell.id, new_cell->earfcn);
   }
 
   // Wait for any pending PHICH
-  int cnt = 0;
   while(worker_com->is_any_pending_ack() && cnt < 10) {
     usleep(1000);
     cnt++;
@@ -296,7 +298,7 @@ bool phch_recv::cell_select(phy_interface_rrc::phy_cell_t *new_cell) {
       cell = new_cell->cell;
       if (!set_cell()) {
         Error("Cell Select: Reconfiguring cell\n");
-        return false;
+        goto unlock;
       }
     }
 
@@ -305,7 +307,7 @@ bool phch_recv::cell_select(phy_interface_rrc::phy_cell_t *new_cell) {
       Info("Cell Select: Setting new frequency EARFCN=%d\n", new_cell->earfcn);
       if (set_frequency()) {
         Error("Cell Select: Setting new frequency EARFCN=%d\n", new_cell->earfcn);
-        return false;
+        goto unlock;
       }
       current_earfcn = new_cell->earfcn;
     }
@@ -318,7 +320,6 @@ bool phch_recv::cell_select(phy_interface_rrc::phy_cell_t *new_cell) {
   }
 
   /* SFN synchronization */
-  bool ret = false;
   phy_state.run_sfn_sync();
   if (phy_state.is_camping()) {
     Info("Cell Select: SFN synchronized. CAMPING...\n");
@@ -327,6 +328,7 @@ bool phch_recv::cell_select(phy_interface_rrc::phy_cell_t *new_cell) {
     Info("Cell Select: Could not synchronize SFN\n");
   }
 
+unlock:
   pthread_mutex_unlock(&rrc_mutex);
   return ret;
 }
diff --git a/srsue/src/upper/nas.cc b/srsue/src/upper/nas.cc
index 291a3550f..ad8ae39a8 100644
--- a/srsue/src/upper/nas.cc
+++ b/srsue/src/upper/nas.cc
@@ -242,6 +242,7 @@ bool nas::rrc_connect() {
     }
   } else {
     nas_log->error("Could not establish RRC connection\n");
+    pool->deallocate(dedicatedInfoNAS);
   }
   return false;
 }
diff --git a/srsue/src/upper/rrc.cc b/srsue/src/upper/rrc.cc
index 3f213979d..773a46a53 100644
--- a/srsue/src/upper/rrc.cc
+++ b/srsue/src/upper/rrc.cc
@@ -220,21 +220,11 @@ void rrc::run_tti(uint32_t tti) {
         // If attached but not camping on the cell, perform cell reselection
         if (nas->is_attached()) {
           rrc_log->debug("Running cell selection and reselection in IDLE\n");
-          if (!cell_selection()) {
-            if (!serving_cell->in_sync) {
-              rrc_log->info("Cell selection and reselection in IDLE did not find any suitable cell. Searching again\n");
-              // If can not camp on any cell, search again for new cells
-              phy_interface_rrc::cell_search_ret_t ret = cell_search();
-
-              // TODO: Should not camp on it until we have checked is a valid PLMN
-              if (ret.found == phy_interface_rrc::cell_search_ret_t::CELL_FOUND) {
-                // New cell has been selected, start receiving PCCH
-                mac->pcch_start_rx();
-              }
-            }
-          } else {
+          if (cell_selection()) {
             // New cell has been selected, start receiving PCCH
             mac->pcch_start_rx();
+          } else {
+            rrc_log->warning("Could not find any cell to camp on\n");
           }
         }
         break;
@@ -780,14 +770,12 @@ phy_interface_rrc::cell_search_ret_t rrc::cell_search()
  */
 bool rrc::cell_selection()
 {
-  int candidates = 0;
   // Neighbour cells are sorted in descending order of RSRP
   for (uint32_t i = 0; i < neighbour_cells.size(); i++) {
     if (/*TODO: CHECK that PLMN matches. Currently we don't receive SIB1 of neighbour cells
          * neighbour_cells[i]->plmn_equals(selected_plmn_id) && */
         neighbour_cells[i]->in_sync) // matches S criteria
     {
-      candidates++;
       // If currently connected, verify cell selection criteria
       if (!serving_cell->in_sync ||
           (cell_selection_criteria(neighbour_cells[i]->get_rsrp())  &&
@@ -814,7 +802,15 @@ bool rrc::cell_selection()
       }
     }
   }
-  return false;
+  if (serving_cell->in_sync) {
+    return true;
+  }
+  // If can not find any suitable cell, search again
+  rrc_log->info("Cell selection and reselection in IDLE did not find any suitable cell. Searching again\n");
+  // If can not camp on any cell, search again for new cells
+  phy_interface_rrc::cell_search_ret_t ret = cell_search();
+
+  return ret.found == phy_interface_rrc::cell_search_ret_t::CELL_FOUND;
 }
 
 // Cell selection criteria Section 5.2.3.2 of 36.304