Merge "Add /system_ext/etc/selinux/ to the debug policy search path for GSI" into sc-v2-dev

3 files changed, 58 insertions, 14 deletions

diff --git a/init/Android.bp b/init/Android.bp
index 7eeafa24b..a57f3a407 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -89,7 +89,19 @@ init_host_sources = [
     "host_init_verifier.cpp",
 ]
 
-cc_defaults {
+soong_config_module_type {
+    name: "libinit_cc_defaults",
+    module_type: "cc_defaults",
+    config_namespace: "ANDROID",
+    bool_variables: [
+        "PRODUCT_INSTALL_DEBUG_POLICY_TO_SYSTEM_EXT",
+    ],
+    properties: [
+        "cflags",
+    ],
+}
+
+libinit_cc_defaults {
     name: "init_defaults",
     sanitize: {
         misc_undefined: ["signed-integer-overflow"],
@@ -109,6 +121,7 @@ cc_defaults {
         "-DDUMP_ON_UMOUNT_FAILURE=0",
         "-DSHUTDOWN_ZERO_TIMEOUT=0",
         "-DINIT_FULL_SOURCES",
+        "-DINSTALL_DEBUG_POLICY_TO_SYSTEM_EXT=0",
     ],
     product_variables: {
         debuggable: {
@@ -137,6 +150,14 @@ cc_defaults {
             cppflags: ["-DUSER_MODE_LINUX"],
         },
     },
+    soong_config_variables: {
+        PRODUCT_INSTALL_DEBUG_POLICY_TO_SYSTEM_EXT: {
+            cflags: [
+                "-UINSTALL_DEBUG_POLICY_TO_SYSTEM_EXT",
+                "-DINSTALL_DEBUG_POLICY_TO_SYSTEM_EXT=1",
+            ],
+        },
+    },
     static_libs: [
         "libavb",
         "libc++fs",
diff --git a/init/first_stage_init.cpp b/init/first_stage_init.cpp
index 78e5b60a1..c7b7b0c13 100644
--- a/init/first_stage_init.cpp
+++ b/init/first_stage_init.cpp
@@ -330,14 +330,21 @@ int FirstStageMain(int argc, char** argv) {
     // If "/force_debuggable" is present, the second-stage init will use a userdebug
     // sepolicy and load adb_debug.prop to allow adb root, if the device is unlocked.
     if (access("/force_debuggable", F_OK) == 0) {
+        constexpr const char adb_debug_prop_src[] = "/adb_debug.prop";
+        constexpr const char userdebug_plat_sepolicy_cil_src[] = "/userdebug_plat_sepolicy.cil";
         std::error_code ec;  // to invoke the overloaded copy_file() that won't throw.
-        if (!fs::copy_file("/adb_debug.prop", kDebugRamdiskProp, ec) ||
-            !fs::copy_file("/userdebug_plat_sepolicy.cil", kDebugRamdiskSEPolicy, ec)) {
-            LOG(ERROR) << "Failed to setup debug ramdisk";
-        } else {
-            // setenv for second-stage init to read above kDebugRamdisk* files.
-            setenv("INIT_FORCE_DEBUGGABLE", "true", 1);
+        if (access(adb_debug_prop_src, F_OK) == 0 &&
+            !fs::copy_file(adb_debug_prop_src, kDebugRamdiskProp, ec)) {
+            LOG(WARNING) << "Can't copy " << adb_debug_prop_src << " to " << kDebugRamdiskProp
+                         << ": " << ec.message();
+        }
+        if (access(userdebug_plat_sepolicy_cil_src, F_OK) == 0 &&
+            !fs::copy_file(userdebug_plat_sepolicy_cil_src, kDebugRamdiskSEPolicy, ec)) {
+            LOG(WARNING) << "Can't copy " << userdebug_plat_sepolicy_cil_src << " to "
+                         << kDebugRamdiskSEPolicy << ": " << ec.message();
         }
+        // setenv for second-stage init to read above kDebugRamdisk* files.
+        setenv("INIT_FORCE_DEBUGGABLE", "true", 1);
     }
 
     if (ForceNormalBoot(cmdline, bootconfig)) {
diff --git a/init/selinux.cpp b/init/selinux.cpp
index 42d302324..29c0ff3ba 100644
--- a/init/selinux.cpp
+++ b/init/selinux.cpp
@@ -295,6 +295,25 @@ bool IsSplitPolicyDevice() {
     return access(plat_policy_cil_file, R_OK) != -1;
 }
 
+std::optional<const char*> GetUserdebugPlatformPolicyFile() {
+    // See if we need to load userdebug_plat_sepolicy.cil instead of plat_sepolicy.cil.
+    const char* force_debuggable_env = getenv("INIT_FORCE_DEBUGGABLE");
+    if (force_debuggable_env && "true"s == force_debuggable_env && AvbHandle::IsDeviceUnlocked()) {
+        const std::vector<const char*> debug_policy_candidates = {
+#if INSTALL_DEBUG_POLICY_TO_SYSTEM_EXT == 1
+            "/system_ext/etc/selinux/userdebug_plat_sepolicy.cil",
+#endif
+            kDebugRamdiskSEPolicy,
+        };
+        for (const char* debug_policy : debug_policy_candidates) {
+            if (access(debug_policy, F_OK) == 0) {
+                return debug_policy;
+            }
+        }
+    }
+    return std::nullopt;
+}
+
 struct PolicyFile {
     unique_fd fd;
     std::string path;
@@ -310,13 +329,10 @@ bool OpenSplitPolicy(PolicyFile* policy_file) {
     // secilc is invoked to compile the above three policy files into a single monolithic policy
     // file. This file is then loaded into the kernel.
 
-    // See if we need to load userdebug_plat_sepolicy.cil instead of plat_sepolicy.cil.
-    const char* force_debuggable_env = getenv("INIT_FORCE_DEBUGGABLE");
-    bool use_userdebug_policy =
-            ((force_debuggable_env && "true"s == force_debuggable_env) &&
-             AvbHandle::IsDeviceUnlocked() && access(kDebugRamdiskSEPolicy, F_OK) == 0);
+    const auto userdebug_plat_sepolicy = GetUserdebugPlatformPolicyFile();
+    const bool use_userdebug_policy = userdebug_plat_sepolicy.has_value();
     if (use_userdebug_policy) {
-        LOG(WARNING) << "Using userdebug system sepolicy";
+        LOG(INFO) << "Using userdebug system sepolicy " << *userdebug_plat_sepolicy;
     }
 
     // Load precompiled policy from vendor image, if a matching policy is found there. The policy
@@ -413,7 +429,7 @@ bool OpenSplitPolicy(PolicyFile* policy_file) {
     // clang-format off
     std::vector<const char*> compile_args {
         "/system/bin/secilc",
-        use_userdebug_policy ? kDebugRamdiskSEPolicy: plat_policy_cil_file,
+        use_userdebug_policy ? *userdebug_plat_sepolicy : plat_policy_cil_file,
         "-m", "-M", "true", "-G", "-N",
         "-c", version_as_string.c_str(),
         plat_mapping_file.c_str(),