diff --git a/app/views/repositories/tags.html.haml b/app/views/repositories/tags.html.haml
index ba4692f..193cb2e 100644
--- a/app/views/repositories/tags.html.haml
+++ b/app/views/repositories/tags.html.haml
@@ -15,7 +15,7 @@
             = link_to project_commits_path(@project, tag.name), class: "" do
               %i.icon-tag
               = tag.name
-          %small.light= truncate(tag.message, length: 70)
+          %small.light= truncate(tag.message || '', length: 70)
         %td
           = image_tag gravatar_icon(commit.author_email), class: "avatar s16"
           = link_to project_commit_path(@project, commit.id), class: 'commit_short_id' do
diff --git a/lib/gitlab/graph_commit.rb b/lib/gitlab/graph_commit.rb
index d3668a9..188fc42 100644
--- a/lib/gitlab/graph_commit.rb
+++ b/lib/gitlab/graph_commit.rb
@@ -9,7 +9,7 @@ module Gitlab
 
     def self.to_graph(project)
       @repo = project.repo
-      commits = Grit::Commit.find_all(@repo, nil, {max_count: 650})
+      commits = Grit::Commit.find_all(@repo, nil, {max_count: 650}).dup
 
       ref_cache = {}
 
--
libgit2 0.21.2