init: start ueventd in the default mount namespace
Init starts ueventd in the default mount namespace to support loading
firmware from APEXes.
Bug: 155023652
Test: devices boots
adb$ nsenter -t (pid of ueventd) -m ls /apex
=> shows all APEXes
Change-Id: Ibb8b33a07eb014752275e3bca4541b8b694dc64b
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 0ac66f2..0b456e7 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -1221,6 +1221,20 @@
return {};
}
+static Result<void> MountLinkerConfigForDefaultNamespace() {
+ // No need to mount linkerconfig for default mount namespace if the path does not exist (which
+ // would mean it is already mounted)
+ if (access("/linkerconfig/default", 0) != 0) {
+ return {};
+ }
+
+ if (mount("/linkerconfig/default", "/linkerconfig", nullptr, MS_BIND | MS_REC, nullptr) != 0) {
+ return ErrnoError() << "Failed to mount linker configuration for default mount namespace.";
+ }
+
+ return {};
+}
+
static bool IsApexUpdatable() {
static bool updatable = android::sysprop::ApexProperties::updatable().value_or(false);
return updatable;
@@ -1319,11 +1333,14 @@
}
static Result<void> do_enter_default_mount_ns(const BuiltinArguments& args) {
- if (SwitchToDefaultMountNamespace()) {
- return {};
- } else {
- return Error() << "Failed to enter into default mount namespace";
+ if (auto result = SwitchToMountNamespaceIfNeeded(NS_DEFAULT); !result.ok()) {
+ return result.error();
}
+ if (auto result = MountLinkerConfigForDefaultNamespace(); !result.ok()) {
+ return result.error();
+ }
+ LOG(INFO) << "Switched to default mount namespace";
+ return {};
}
// Builtin-function-map start