Swift: Add realm path-injection sinks.

Author: geoffw0

swift/ql/lib/codeql/swift/security/PathInjectionExtensions.qll

@@ -127,7 +127,13 @@ private class PathInjectionSinks extends SinkModelCsv {
         ";DatabasePool;true;init(path:configuration:);;;Argument[0];path-injection",
         ";DatabaseQueue;true;init(path:configuration:);;;Argument[0];path-injection",
         ";DatabaseSnapshotPool;true;init(path:configuration:);;;Argument[0];path-injection",
-        ";SerializedDatabase;true;init(path:configuration:defaultLabel:purpose:);;;Argument[0];path-injection"
+        ";SerializedDatabase;true;init(path:configuration:defaultLabel:purpose:);;;Argument[0];path-injection",
+        // Realm
+        ";Realm.Configuration;true;init(fileURL:inMemoryIdentifier:syncConfiguration:encryptionKey:readOnly:schemaVersion:migrationBlock:deleteRealmIfMigrationNeeded:shouldCompactOnLaunch:objectTypes:);;;Argument[0];path-injection",
+        ";Realm.Configuration;true;init(fileURL:inMemoryIdentifier:syncConfiguration:encryptionKey:readOnly:schemaVersion:migrationBlock:deleteRealmIfMigrationNeeded:shouldCompactOnLaunch:objectTypes:seedFilePath:);;;Argument[0];path-injection",
+        ";Realm.Configuration;true;init(fileURL:inMemoryIdentifier:syncConfiguration:encryptionKey:readOnly:schemaVersion:migrationBlock:deleteRealmIfMigrationNeeded:shouldCompactOnLaunch:objectTypes:seedFilePath:);;;Argument[10];path-injection",
+        ";Realm.Configuration;true;fileURL;;;;path-injection",
+        ";Realm.Configuration;true;seedFilePath;;;;path-injection",
       ]
   }
 }

swift/ql/test/query-tests/Security/CWE-022/PathInjectionTest.expected

@@ -0,0 +1,2 @@
+| testPathInjection.swift:314:35:314:35 | remoteUrl | Unexpected result: hasPathInjection=208 |
+| testPathInjection.swift:316:40:316:40 | remoteUrl | Unexpected result: hasPathInjection=208 |

swift/ql/test/query-tests/Security/CWE-022/testPathInjection.swift

@@ -311,9 +311,9 @@ func test() {
     // Realm
 
 	_ = Realm.Configuration(fileURL: safeUrl) // GOOD
-	_ = Realm.Configuration(fileURL: remoteUrl) // BAD [NOT DETECTED]
+	_ = Realm.Configuration(fileURL: remoteUrl) // BAD
 	_ = Realm.Configuration(seedFilePath: safeUrl) // GOOD
-	_ = Realm.Configuration(seedFilePath: remoteUrl) // BAD [NOT DETECTED]
+	_ = Realm.Configuration(seedFilePath: remoteUrl) // BAD
 
 	var config = Realm.Configuration() // GOOD
 	config.fileURL = safeUrl // GOOD