Add /system_ext/etc/selinux/ to the debug policy search path for GSI
This change only *adds* /system_ext/etc/selinux to the debug policy
search path, and does not change any preconditions to load the debug
policy. The device still needs to be bootloader-unlocked and has the
debug ramdisk flashed to be able to use the debug policy. The only thing
changed is that now the debug policy can be loaded from /system_ext or
/debug_ramdisk when system partition is compliance testing GSI.
The debug policy in the boot ramdisk may be outdated if the system
partition is flashed with a image built from a different revision.
This happens frequently when running the compliance testing VTS, where
the device is flashed with (A) GSI and (B) device vendor image & debug
boot image, and (A) and (B) are built from different git revisions.
To address this, we install a copy of the debug policy under
/system_ext, so that the version desync between (A) & (B) wouldn't be a
problem anymore because (A) no longer relies on the debug policy file
from (B).
Bug: 188067818
Test: Flash RQ2A.201207.001 bramble-user with debug ramdisk & flash
gsi_arm64-user from master, device can boot and `adb root` works
Change-Id: I4d6235c73472e4d97619b2230292e6a0bc4b3e05
Merged-In: I4d6235c73472e4d97619b2230292e6a0bc4b3e05
(cherry picked from commit 650b29d2349253a0dd6000564ccb2c19b51352db)
diff --git a/init/selinux.cpp b/init/selinux.cpp
index 42d3023..29c0ff3 100644
--- a/init/selinux.cpp
+++ b/init/selinux.cpp
@@ -295,6 +295,25 @@
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 @@
// 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 @@
// 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(),