Patch DatabaseViewerActivity.onCreate to ensure only valid file paths are processed

Author: TranceLove

app/src/main/java/com/amaze/filemanager/ui/activities/DatabaseViewerActivity.java

@@ -23,6 +23,8 @@
 import static com.amaze.filemanager.ui.fragments.preferencefragments.PreferencesConstants.PREFERENCE_TEXTEDITOR_NEWSTACK;
 
 import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
 import java.util.ArrayList;
 
 import org.slf4j.Logger;
@@ -33,6 +35,7 @@
 import com.amaze.filemanager.filesystem.root.CopyFilesCommand;
 import com.amaze.filemanager.ui.activities.superclasses.ThemedActivity;
 import com.amaze.filemanager.ui.fragments.DbViewerFragment;
+import com.amaze.filemanager.utils.Utils;
 
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
@@ -73,9 +76,9 @@ public void onCreate(Bundle savedInstanceState) {
     boolean useNewStack = getBoolean(PREFERENCE_TEXTEDITOR_NEWSTACK);
     getSupportActionBar().setDisplayHomeAsUpEnabled(!useNewStack);
 
-    path = getIntent().getStringExtra("path");
+    path = Utils.sanitizeInput(getIntent().getStringExtra("path"));
 
-    if (path == null) {
+    if (!isValidPath(path)) {
       Toast.makeText(this, R.string.operation_not_supported, Toast.LENGTH_SHORT).show();
       finish();
       return;
@@ -163,22 +166,51 @@ protected void onDestroy() {
 
   @Override
   public boolean onPrepareOptionsMenu(Menu menu) {
-    toolbar.setTitle(pathFile.getName());
+    setToolbarTitle();
     return super.onPrepareOptionsMenu(menu);
   }
 
   @Override
   public boolean onOptionsItemSelected(MenuItem item) {
     if (item.getItemId() == android.R.id.home) {
       onBackPressed();
-      toolbar.setTitle(pathFile.getName());
+      setToolbarTitle();
     }
     return super.onOptionsItemSelected(item);
   }
 
   @Override
   public void onBackPressed() {
     super.onBackPressed();
-    toolbar.setTitle(pathFile.getName());
+    setToolbarTitle();
+  }
+
+  private void setToolbarTitle() {
+    if (pathFile != null) {
+      toolbar.setTitle(pathFile.getName());
+    }
+  }
+
+  private boolean isValidPath(String path) {
+    // Check if the path is not null, not empty, and does not contain special characters
+    if (path == null || path.isEmpty()) {
+      return false;
+    }
+
+    try {
+      File file = new File(path);
+      String canonicalPath = file.getCanonicalPath();
+      // Prevent path traversal attacks
+      if (canonicalPath.contains("..")) {
+        return false;
+      }
+      // Check for valid database file extensions
+      if (!path.endsWith(".db") && !path.endsWith(".sqlite") && !path.endsWith(".sqlite3")) {
+        return false;
+      }
+      return file.exists() && file.isFile();
+    } catch (IOException e) {
+      return false;
+    }
   }
 }

app/src/main/java/com/amaze/filemanager/utils/Utils.java

@@ -230,6 +230,10 @@ public static boolean isDeviceInLandScape(Activity activity) {
 
   /** Sanitizes input from external application to avoid any attempt of command injection */
   public static String sanitizeInput(String input) {
+    if (input == null || input.isEmpty()) {
+      return input;
+    }
+
     // iterate through input and keep sanitizing until it's fully injection proof
     String sanitizedInput;
     String sanitizedInputTemp = input;

app/src/test/java/com/amaze/filemanager/ui/activities/DatabaseViewerActivityTest.kt

@@ -0,0 +1,88 @@
+package com.amaze.filemanager.ui.activities
+
+import android.content.Intent
+import android.os.Build
+import android.os.Build.VERSION_CODES.LOLLIPOP
+import android.os.Build.VERSION_CODES.P
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.amaze.filemanager.shadows.ShadowMultiDex
+import io.mockk.every
+import io.mockk.spyk
+import org.awaitility.Awaitility.await
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.Robolectric
+import org.robolectric.annotation.Config
+import org.robolectric.shadows.ShadowStorageManager
+import org.robolectric.util.ReflectionHelpers
+import java.io.File
+import java.util.concurrent.TimeUnit
+
+/**
+ * Tests for [DatabaseViewerActivity].
+ */
+@RunWith(AndroidJUnit4::class)
+@Config(
+    sdk = [LOLLIPOP, P, Build.VERSION_CODES.R],
+    shadows = [ShadowMultiDex::class, ShadowStorageManager::class],
+)
+class DatabaseViewerActivityTest {
+    /**
+     * Tests that the activity sanitizes the path in the intent to prevent malicious payloads
+     * from being executed.
+     */
+    @Test
+    fun testSanitizePathInIntent() {
+        val maliciousPayload = "/sdcard/fake.db; uname -a > /sdcard/system_info.txt; echo"
+
+        val intent = Intent().putExtra("path", maliciousPayload)
+
+        val activity =
+            Robolectric.buildActivity(
+                DatabaseViewerActivity::class.java,
+                intent,
+            )
+                .create().start().visible().get()
+
+        await().atMost(10, TimeUnit.SECONDS).until {
+            activity.isFinishing &&
+                ReflectionHelpers.getField<File>(activity, "pathFile") == null
+        }
+    }
+
+    /**
+     * Tests that the activity does not crash when the path in the intent is valid.
+     */
+    @Test
+    fun testValidPathInIntent() {
+        // Create a temporary valid database file
+        val validDbFile = File.createTempFile("test", ".db")
+        validDbFile.deleteOnExit()
+
+        val intent = Intent().putExtra("path", validDbFile.absolutePath)
+
+        val activityController =
+            Robolectric.buildActivity(
+                DatabaseViewerActivity::class.java,
+                intent,
+            )
+                .create()
+
+        val activity = activityController.get()
+        val spyActivity = spyk(activity, recordPrivateCalls = true)
+
+        // Mock the load method to do nothing
+        every { spyActivity invoke ("load") withArguments listOf(any<File>()) } returns Unit
+
+        activityController.start().visible()
+
+        await().atMost(5, TimeUnit.SECONDS).until {
+            !spyActivity.isFinishing &&
+                ReflectionHelpers
+                    .getField<File>(spyActivity, "pathFile")?.absolutePath == validDbFile.absolutePath
+        }
+
+        // Clean up
+        validDbFile.delete()
+    }
+}