From 1ba4f8a8396da9d7e47c4034f050548f84d14034 Mon Sep 17 00:00:00 2001
From: Alice Wang <aliceywang@google.com>
Date: Mon, 23 Jan 2023 13:49:39 +0000
Subject: [PATCH] [avb][fuzzer] Fuzz pvmfw payload_verify for kernel without
 footer

Bug: 260574387
Test: Run fuzzer.
Change-Id: Ie2ce843000976829f3f7783cca956cf5a4089bb7
---
 pvmfw/avb/fuzz/Android.bp                     | 34 +++++++++++++++++++
 .../avb/fuzz/without_footer_verify_fuzzer.rs  | 28 +++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 pvmfw/avb/fuzz/Android.bp
 create mode 100644 pvmfw/avb/fuzz/without_footer_verify_fuzzer.rs

diff --git a/pvmfw/avb/fuzz/Android.bp b/pvmfw/avb/fuzz/Android.bp
new file mode 100644
index 00000000..451fd8a0
--- /dev/null
+++ b/pvmfw/avb/fuzz/Android.bp
@@ -0,0 +1,34 @@
+// Copyright 2023, 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 {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+rust_fuzz {
+    name: "avb_kernel_without_footer_verify_fuzzer",
+    srcs: ["without_footer_verify_fuzzer.rs"],
+    rustlibs: [
+        "libpvmfw_avb_nostd",
+    ],
+    fuzz_config: {
+        cc: [
+            "android-kvm@google.com",
+        ],
+        fuzz_on_haiku_device: true,
+        fuzz_on_haiku_host: true,
+    },
+}
+
+// TODO(b/260574387): Add avb_kernel_with_footer_verify_fuzzer
diff --git a/pvmfw/avb/fuzz/without_footer_verify_fuzzer.rs b/pvmfw/avb/fuzz/without_footer_verify_fuzzer.rs
new file mode 100644
index 00000000..fc8fa85b
--- /dev/null
+++ b/pvmfw/avb/fuzz/without_footer_verify_fuzzer.rs
@@ -0,0 +1,28 @@
+// Copyright 2023, 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.
+
+#![allow(missing_docs)]
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+use pvmfw_avb::verify_payload;
+
+fuzz_target!(|kernel: &[u8]| {
+    // This fuzzer is mostly supposed to catch the memory corruption in
+    // AVB footer parsing. It is unlikely that the randomly generated
+    // kernel can pass the kernel verification, so the value of `initrd`
+    // is not so important as we won't reach initrd verification with
+    // this fuzzer.
+    let _ = verify_payload(kernel, /*initrd=*/ None, &[0u8; 64]);
+});