Merge pull request #3249 from MichaelEischer/fix-dropped-gs-error

gs: Don't drop error when finishing upload

changelog/unreleased/pull-3249

@@ -0,0 +1,7 @@
+Bugfix: Better error handling for gs backend
+
+The gs backend did not notice when the last steep of completing a file upload
+failed. Under rare circumstance, this might be able to cause missing files in
+the backup repository. This has been fixed.
+
+https://github.com/restic/restic/pull/3249

internal/backend/gs/gs.go

@@ -235,7 +235,10 @@ func (be *Backend) Save(ctx context.Context, h restic.Handle, rd restic.RewindRe
 	w := be.bucket.Object(objName).NewWriter(ctx)
 	w.ChunkSize = 0
 	wbytes, err := io.Copy(w, rd)
-	w.Close()
+	cerr := w.Close()
+	if err == nil {
+		err = cerr
+	}
 
 	be.sem.ReleaseToken()