Validate the commit using all known email addresses for the user

app/models/push_rule.rb

@@ -33,11 +33,11 @@ class PushRule < ActiveRecord::Base
     commit.has_signature?
   end
 
-  def author_allowed?(committer_email, current_user_email)
+  def committer_allowed?(committer, current_user)
     return true unless available?(:commit_author_check)
     return true unless commit_author_check
 
-    committer_email.casecmp(current_user_email) == 0
+    current_user == committer
   end
 
   def commit_message_allowed?(message)

lib/gitlab/checks/change_access.rb

@@ -213,7 +213,7 @@ module Gitlab
           return "Author's email '#{commit.author_email}' does not follow the pattern '#{push_rule.author_email_regex}'"
         end
 
-        unless push_rule.author_allowed?(commit.committer_email, user_access.user.email)
+        unless push_rule.committer_allowed?(commit.committer, user_access.user)
           return "You can only push your own commits to this repository"
         end
 

spec/lib/gitlab/checks/change_access_spec.rb

@@ -456,6 +456,13 @@ describe Gitlab::Checks::ChangeAccess do
           it 'does not return an error' do
             expect { subject }.not_to raise_error
           end
+
+          it 'allows the commit when they were done with another email that belongs to the current user' do
+            allow_any_instance_of(Commit).to receive(:committer_email).and_return('secondary_email@user.com')
+            user.emails.create(email: 'secondary_email@user.com')
+
+            expect { subject }.not_to raise_error
+          end
         end
 
         context 'with a commit from a different user' do

spec/services/merge_requests/merge_service_spec.rb

@@ -352,4 +352,6 @@ describe MergeRequests::MergeService do
       end
     end
   end
+
+  context ''
 end