This only occurs if you were unfortunate enough to name the label of your registration field on a product, "Registration", as it's hard coded to alter the extra field info without setting a label. This causes errors in the field ui for unrelated products that do not have registration fields. Just updated to the latest version of Drupal so that may be related.
Simple fix is to not name your field label "Registration".
Notice: Undefined index: label in field_ui_display_overview_form() (line 1126 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1130 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1139 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1158 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1126 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1130 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1139 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Notice: Undefined index: label in field_ui_display_overview_form() (line 1158 of /var/www/drupal/modules/field_ui/field_ui.admin.inc).
Closed: outdated
2.0
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