fix: Time-of-check Time-of-use bug in session management

Author: ghislainbourgeois

internal/smf/create.go

@@ -112,7 +112,7 @@ func (s *SMF) CreateSmContext(ctx context.Context, supi etsi.SUPI, pduSessionID
 				}
 			}
 			smContext.Mutex.Unlock()
-			s.RemoveSession(ctx, smContext.CanonicalName())
+			s.removeSessionUnlocked(ctx, smContext.CanonicalName())
 		}
 	}()
 

internal/smf/release.go

@@ -25,7 +25,10 @@ func (s *SMF) ReleaseSmContext(ctx context.Context, smContextRef string) error {
 	)
 	defer span.End()
 
-	smContext := s.GetSession(smContextRef)
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	smContext := s.pool[smContextRef]
 	if smContext == nil {
 		span.RecordError(fmt.Errorf("sm context not found"))
 		span.SetStatus(codes.Error, "sm context not found")
@@ -54,12 +57,12 @@ func (s *SMF) ReleaseSmContext(ctx context.Context, smContextRef string) error {
 	if err != nil {
 		span.RecordError(err)
 		span.SetStatus(codes.Error, "failed to release tunnel")
-		s.removeSessionUnlocked(ctx, smContextRef)
+		delete(s.pool, smContextRef)
 
 		return fmt.Errorf("release tunnel failed: %v", err)
 	}
 
-	s.removeSessionUnlocked(ctx, smContextRef)
+	delete(s.pool, smContextRef)
 
 	return nil
 }