fix: UI hangs on image pull errors

cmd/grype/internal/ui/ui.go

@@ -82,12 +82,15 @@ func (m *UI) Teardown(force bool) error {
 	if !force {
 		m.handler.Wait()
 		m.program.Quit()
+		// typically in all cases we would want to wait for the UI to finish. However there are still error cases
+		// that are not accounted for, resulting in hangs. For now, we'll just wait for the UI to finish in the
+		// happy path only. There will always be an indication of the problem to the user via reporting the error
+		// string from the worker (outside of the UI after teardown).
+		m.running.Wait()
 	} else {
 		m.program.Kill()
 	}
 
-	m.running.Wait()
-
 	// TODO: allow for writing out the full log output to the screen (only a partial log is shown currently)
 	// this needs coordination to know what the last frame event is to change the state accordingly (which isn't possible now)
 

grype/pkg/syft_provider.go

@@ -1,6 +1,7 @@
 package pkg
 
 import (
+	"github.com/anchore/grype/internal/log"
 	"github.com/anchore/stereoscope/pkg/image"
 	"github.com/anchore/syft/syft"
 	"github.com/anchore/syft/syft/sbom"
@@ -13,7 +14,13 @@ func syftProvider(userInput string, config ProviderConfig) ([]Package, Context,
 		return nil, Context{}, nil, err
 	}
 
-	defer src.Close()
+	defer func() {
+		if src != nil {
+			if err := src.Close(); err != nil {
+				log.Tracef("unable to close source: %+v", err)
+			}
+		}
+	}()
 
 	catalog, relationships, theDistro, err := syft.CatalogPackages(src, config.CatalogingOptions)
 	if err != nil {