1 files changed, 11 insertions, 1 deletions
diff --git a/app/models/merge_request_diff_file.rb b/app/models/merge_request_diff_file.rb
index 23319445a38..55ff4250c2d 100644
--- a/app/models/merge_request_diff_file.rb
+++ b/app/models/merge_request_diff_file.rb
@@ -25,6 +25,16 @@ class MergeRequestDiffFile < ApplicationRecord
         super
       end
 
-    binary? ? content.unpack1('m0') : content
+    return content unless binary?
+
+    # If the data isn't valid base64, return it as-is, since it's almost certain
+    # to be a valid diff. Parsing it as a diff will fail if it's something else.
+    #
+    # https://gitlab.com/gitlab-org/gitlab/-/issues/240921
+    begin
+      content.unpack1('m0')
+    rescue ArgumentError
+      content
+    end
   end
 end