MDL-68632 quizaccess_seb: Limit privacy queriyes to the quiz module

Without this, joins are performed against the course_modules table purely on
the instance id - other modules can share this ID, resulting in incorrect
contexts being pulled in.

mod/quiz/accessrule/seb/classes/privacy/provider.php

@@ -93,12 +93,14 @@ public static function get_contexts_for_userid(int $userid): contextlist {
         $sql = "SELECT c.id
                   FROM {quizaccess_seb_quizsettings} qs
                   JOIN {course_modules} cm ON cm.instance = qs.quizid
+                  JOIN {modules} m ON cm.module = m.id AND m.name = :modulename
                   JOIN {context} c ON c.instanceid = cm.id AND c.contextlevel = :context
                  WHERE qs.usermodified = :userid
               GROUP BY c.id";
 
         $params = [
             'context' => CONTEXT_MODULE,
+            'modulename' => 'quiz',
             'userid' => $userid
         ];
 
@@ -108,6 +110,7 @@ public static function get_contexts_for_userid(int $userid): contextlist {
                   FROM {quizaccess_seb_template} tem
                   JOIN {quizaccess_seb_quizsettings} qs ON qs.templateid = tem.id
                   JOIN {course_modules} cm ON cm.instance = qs.quizid
+                  JOIN {modules} m ON cm.module = m.id AND m.name = :modulename
                   JOIN {context} c ON c.instanceid = cm.id AND c.contextlevel = :context
                  WHERE qs.usermodified = :userid
               GROUP BY c.id";
@@ -139,6 +142,7 @@ public static function export_user_data(approved_contextlist $contextlist) {
         }
 
         list($insql, $params) = $DB->get_in_or_equal($cmids, SQL_PARAMS_NAMED);
+        $params['modulename'] = 'quiz';
 
         // SEB quiz settings.
         $sql = "SELECT qs.id as id,
@@ -148,6 +152,7 @@ public static function export_user_data(approved_contextlist $contextlist) {
                        qs.timemodified as timemodified
                   FROM {quizaccess_seb_quizsettings} qs
                   JOIN {course_modules} cm ON cm.instance = qs.quizid
+                  JOIN {modules} m ON cm.module = m.id AND m.name = :modulename
                  WHERE cm.id {$insql}";
 
         $quizsettingslist = $DB->get_records_sql($sql, $params);
@@ -180,6 +185,7 @@ public static function export_user_data(approved_contextlist $contextlist) {
                   FROM {quizaccess_seb_template} tem
                   JOIN {quizaccess_seb_quizsettings} qs ON qs.templateid = tem.id
                   JOIN {course_modules} cm ON cm.instance = qs.quizid
+                  JOIN {modules} m ON cm.module = m.id AND m.name = :modulename
                  WHERE cm.id {$insql}";
 
         $templatesettingslist = $DB->get_records_sql($sql, $params);
@@ -262,8 +268,9 @@ public static function get_users_in_context(userlist $userlist) {
         $sql = "SELECT qs.usermodified AS userid
                   FROM {quizaccess_seb_quizsettings} qs
                   JOIN {course_modules} cm ON cm.instance = qs.quizid
+                  JOIN {modules} m ON cm.module = m.id AND m.name = ?
                  WHERE cm.id = ?";
-        $params = [$context->instanceid];
+        $params = ['quiz', $context->instanceid];
         $userlist->add_from_sql('userid', $sql, $params);
     }
 

mod/quiz/accessrule/seb/tests/privacy_provider_test.php

@@ -99,6 +99,11 @@ public function test_export_user_data() {
 
         $context = context_module::instance($this->quiz->cmid);
 
+        // Add another course_module of a differenty type - doing this lets us
+        // test that the data exporter is correctly limiting its selection to
+        // the quiz and not anything with the same instance id.
+        $this->getDataGenerator()->create_module('label', array('course' => $this->course->id));
+
         $contextlist = provider::get_contexts_for_userid($this->user->id);
         $approvedcontextlist = new approved_contextlist(
             $this->user,