STS test for Android Security CVE-2020-0146

Test: [sts-tradefed run sts-engbuild-no-spl-lock -m CtsSecurityBulletinHostTestCases -t android.security.cts.CVE_2020_0461#testPocCVE_2020_0461]
Bug: 170662025
Bug: 169162127
Change-Id: I9f51c928e31122688182a4f23c11a0c95455fbca
diff --git a/hostsidetests/securitybulletin/src/android/security/cts/CVE_2020_0461.java b/hostsidetests/securitybulletin/src/android/security/cts/CVE_2020_0461.java
new file mode 100644
index 0000000..92aa626
--- /dev/null
+++ b/hostsidetests/securitybulletin/src/android/security/cts/CVE_2020_0461.java
@@ -0,0 +1,61 @@
+/**
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.cts;
+
+import android.platform.test.annotations.SecurityTest;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import com.android.tradefed.testtype.DeviceJUnit4ClassRunner;
+
+import static org.junit.Assume.assumeTrue;
+import static org.junit.Assume.assumeThat;
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.*;
+
+@RunWith(DeviceJUnit4ClassRunner.class)
+public class CVE_2020_0461 extends SecurityTestCase {
+
+    /**
+     * b/162741784
+     */
+    @Test
+    @SecurityTest(minPatchLevel = "2020-11")
+    public void testPocCVE_2020_0461() throws Exception {
+        //conditions
+        String cpu = AdbUtils.runCommandLine("getprop ro.product.cpu.abi", getDevice());
+        assumeThat(cpu, equalTo("arm64-v8a"));
+        assumeTrue(containsDriver(getDevice(), "/proc/config.gz"));
+        assumeTrue(containsDriver(getDevice(),
+            "/sys/devices/system/cpu/vulnerabilities/meltdown"));
+        String meltdown = AdbUtils.runCommandLine(
+            "cat /sys/devices/system/cpu/vulnerabilities/meltdown", getDevice());
+        assumeThat(meltdown, equalTo("Vulnerable"));
+
+        //test
+        AdbUtils.runCommandLine("cp /proc/config.gz /data/local/tmp", getDevice());
+        AdbUtils.runCommandLine("gunzip /data/local/tmp/config.gz", getDevice());
+        String output = AdbUtils.runCommandLine(
+            "grep CONFIG_UNMAP_KERNEL_AT_EL0 /data/local/tmp/config", getDevice());
+        AdbUtils.runCommandLine("rm /data/local/tmp/config", getDevice());
+
+        // This is a bad output
+        // "" - empty output
+        // "CONFIG_UNMAP_KERNEL_AT_EL0 is not set"
+        assertFalse(output.isEmpty());
+        assertNotMatches("is not set", output);
+    }
+}