1 files changed, 21 insertions, 2 deletions
diff --git a/app/services/security/ci_configuration/base_create_service.rb b/app/services/security/ci_configuration/base_create_service.rb
index 7f3b66d40e1..aaa850fde39 100644
--- a/app/services/security/ci_configuration/base_create_service.rb
+++ b/app/services/security/ci_configuration/base_create_service.rb
@@ -3,7 +3,7 @@
 module Security
   module CiConfiguration
     class BaseCreateService
-      attr_reader :branch_name, :current_user, :project
+      attr_reader :branch_name, :current_user, :project, :name
 
       def initialize(project, current_user)
         @project = project
@@ -41,8 +41,18 @@ module Security
       end
 
       def existing_gitlab_ci_content
-        @gitlab_ci_yml ||= project.ci_config_for(project.repository.root_ref_sha)
+        root_ref = root_ref_sha(project)
+        return if root_ref.nil?
+
+        @gitlab_ci_yml ||= project.ci_config_for(root_ref)
         YAML.safe_load(@gitlab_ci_yml) if @gitlab_ci_yml
+      rescue Psych::BadAlias
+        raise Gitlab::Graphql::Errors::MutationError,
+              ".gitlab-ci.yml with aliases/anchors is not supported. Please change the CI configuration manually."
+      rescue Psych::Exception => e
+        Gitlab::AppLogger.error("Failed to process existing .gitlab-ci.yml: #{e.message}")
+        raise Gitlab::Graphql::Errors::MutationError,
+              "#{name} merge request creation mutation failed"
       end
 
       def successful_change_path
@@ -61,6 +71,15 @@ module Security
           self.class.to_s, action[:action], label: action[:default_values_overwritten].to_s
         )
       end
+
+      def root_ref_sha(project)
+        project.repository.root_ref_sha
+      rescue StandardError => e
+        # this might fail on the very first commit,
+        # and unfortunately it raises a StandardError
+        Gitlab::ErrorTracking.track_exception(e, project_id: project.id)
+        nil
+      end
     end
   end
 end