Prevent crash displaying board configuration dialog zone properties panel.

Set the NETINFO object pointer in the net selection combobox even when it
is not shown.

Harden all code paths in the NET_SELECTOR_COMBOPOPUP object to prevent
dereferencing a null NETINFO_LIST pointer.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/22354

common/widgets/net_selector.cpp

@@ -43,7 +43,7 @@ public:
 
     wxString GetStringValue() const override
     {
-        if( m_selectedNetcode == -1 )
+        if( !m_netinfoList || ( m_selectedNetcode == -1 ) )
             return m_indeterminateLabel;
 
         NETINFO_ITEM* netInfo = m_netinfoList->GetNetItem( m_selectedNetcode );
@@ -111,7 +111,7 @@ public:
             m_selectedNetcode = 0;
             GetComboCtrl()->SetValue( NO_NET );
         }
-        else if( escapedNetName.StartsWith( CREATE_NET, &remainingName ) && !remainingName.IsEmpty() )
+        else if( m_netinfoList && escapedNetName.StartsWith( CREATE_NET, &remainingName ) && !remainingName.IsEmpty() )
         {
             // Remove the first character ':' and all whitespace
             remainingName = remainingName.Mid( 1 ).Trim().Trim( false );
@@ -137,7 +137,7 @@ public:
                 }
             }
         }
-        else
+        else if( m_netinfoList )
         {
             NETINFO_ITEM* netInfo = m_netinfoList->GetNetItem( escapedNetName );
 
@@ -160,6 +160,9 @@ public:
 protected:
     void getListContent( wxArrayString& aNetnames ) override
     {
+        if( !m_netinfoList )
+            return;
+
         wxString      netstring = getFilterValue();
         wxString      filter = netstring.Lower();
 

pcbnew/dialogs/panel_zone_properties.cpp

@@ -60,11 +60,9 @@ PANEL_ZONE_PROPERTIES::PANEL_ZONE_PROPERTIES( wxWindow* aParent, PCB_BASE_FRAME*
         m_gridStyleGap( aFrame, m_staticTextGridGap, m_tcGridStyleGap, m_GridStyleGapUnits ),
         m_islandThreshold( aFrame, m_islandThresholdLabel, m_tcIslandThreshold, m_islandThresholdUnits )
 {
-    if( allowNetSpec )
-    {
-        m_netSelector->SetNetInfo( &m_frame->GetBoard()->GetNetInfo() );
-    }
-    else
+    m_netSelector->SetNetInfo( &m_frame->GetBoard()->GetNetInfo() );
+
+    if( !allowNetSpec )
     {
         m_netLabel->Hide();
         m_netSelector->Hide();
@@ -131,7 +129,10 @@ bool PANEL_ZONE_PROPERTIES::TransferZoneSettingsToWindow()
         return false;
 
     m_tcZoneName->ChangeValue( m_settings->m_Name );
-    m_netSelector->SetSelectedNetcode( std::max( 0, m_settings->m_Netcode ) );
+
+    if( m_netSelector->IsShown() )
+        m_netSelector->SetSelectedNetcode( std::max( 0, m_settings->m_Netcode ) );
+
     m_cbLocked->SetValue( m_settings->m_Locked );
     m_cornerSmoothingChoice->SetSelection( m_settings->GetCornerSmoothingType() );
     m_cornerRadius.SetValue( m_settings->GetCornerRadius() );
@@ -266,6 +267,9 @@ void PANEL_ZONE_PROPERTIES::OnZoneNameChanged( wxCommandEvent& aEvent )
 
 void PANEL_ZONE_PROPERTIES::onNetSelector( wxCommandEvent& aEvent )
 {
+    if( !m_netSelector->IsShown() )
+        return;
+
     updateInfoBar();
 
     // Zones with no net never have islands removed
@@ -396,7 +400,9 @@ bool PANEL_ZONE_PROPERTIES::AcceptOptions( bool aUseExportableSetupOnly )
     if( aUseExportableSetupOnly )
         return true;
 
-    m_settings->m_Netcode = m_netSelector->GetSelectedNetcode();
+    if( m_netSelector->IsShown() )
+        m_settings->m_Netcode = m_netSelector->GetSelectedNetcode();
+
     m_settings->m_Name = m_tcZoneName->GetValue();
 
     m_settings->m_FillMode = m_cbHatched->GetValue() ? ZONE_FILL_MODE::HATCH_PATTERN : ZONE_FILL_MODE::POLYGONS;