Merge pull request #5313 from giuseppe/fix-crash

imagebuildah: fix crash with empty RUN

imagebuildah/stage_executor.go

@@ -1737,11 +1737,15 @@ func (s *StageExecutor) getCreatedBy(node *parser.Node, addedContentSummary stri
 		buildArgs := s.getBuildArgsKey()
 		return "/bin/sh -c #(nop) ARG " + buildArgs
 	case "RUN":
+		shArg := ""
 		buildArgs := s.getBuildArgsResolvedForRun()
+		if len(node.Original) > 4 {
+			shArg = node.Original[4:]
+		}
 		if buildArgs != "" {
-			return "|" + strconv.Itoa(len(strings.Split(buildArgs, " "))) + " " + buildArgs + " /bin/sh -c " + node.Original[4:]
+			return "|" + strconv.Itoa(len(strings.Split(buildArgs, " "))) + " " + buildArgs + " /bin/sh -c " + shArg
 		}
-		result := "/bin/sh -c " + node.Original[4:]
+		result := "/bin/sh -c " + shArg
 		if len(node.Heredocs) > 0 {
 			for _, doc := range node.Heredocs {
 				heredocContent := strings.TrimSpace(doc.Content)

tests/run.bats

@@ -952,3 +952,18 @@ _EOF
 		fi
 	done
 }
+
+@test "empty run statement doesn't crash" {
+	skip_if_no_runtime
+
+	_prefetch alpine
+
+	cd ${TEST_SCRATCH_DIR}
+
+	printf 'FROM alpine\nRUN \\\n echo && echo' > Dockerfile
+	run_buildah bud --pull=false --layers .
+
+	printf 'FROM alpine\nRUN\n echo && echo' > Dockerfile
+	run_buildah ? bud --pull=false --layers .
+        expect_output --substring -- "-c requires an argument"
+}