Take ownership of inherited FDs using the rustutils crate
Bug: 3259955
Test: watch TH
Merged-In: I316a56142401b5f9bcb8ed350280019d7ddab123
Change-Id: I316a56142401b5f9bcb8ed350280019d7ddab123
diff --git a/guest/authfs_service/src/main.rs b/guest/authfs_service/src/main.rs
index 97e684d..be0f1b2 100644
--- a/guest/authfs_service/src/main.rs
+++ b/guest/authfs_service/src/main.rs
@@ -28,7 +28,6 @@
use rustutils::sockets::android_get_control_socket;
use std::ffi::OsString;
use std::fs::{create_dir, read_dir, remove_dir_all, remove_file};
-use std::os::unix::io::{FromRawFd, OwnedFd};
use std::sync::atomic::{AtomicUsize, Ordering};
use authfs_aidl_interface::aidl::com::android::virt::fs::AuthFsConfig::AuthFsConfig;
@@ -108,27 +107,11 @@
Ok(())
}
-/// Prepares a socket file descriptor for the authfs service.
-///
-/// # Safety requirement
-///
-/// The caller must ensure that this function is the only place that claims ownership
-/// of the file descriptor and it is called only once.
-unsafe fn prepare_authfs_service_socket() -> Result<OwnedFd> {
- let raw_fd = android_get_control_socket(AUTHFS_SERVICE_SOCKET_NAME)?;
-
- // Creating OwnedFd for stdio FDs is not safe.
- if [libc::STDIN_FILENO, libc::STDOUT_FILENO, libc::STDERR_FILENO].contains(&raw_fd) {
- bail!("File descriptor {raw_fd} is standard I/O descriptor");
- }
- // SAFETY: Initializing OwnedFd for a RawFd created by the init.
- // We checked that the integer value corresponds to a valid FD and that the caller
- // ensures that this is the only place to claim its ownership.
- Ok(unsafe { OwnedFd::from_raw_fd(raw_fd) })
-}
-
#[allow(clippy::eq_op)]
fn try_main() -> Result<()> {
+ // SAFETY: nobody has taken ownership of the inherited FDs yet.
+ unsafe { rustutils::inherited_fd::init_once()? };
+
let debuggable = env!("TARGET_BUILD_VARIANT") != "user";
let log_level = if debuggable { log::LevelFilter::Trace } else { log::LevelFilter::Info };
android_logger::init_once(
@@ -137,8 +120,7 @@
clean_up_working_directory()?;
- // SAFETY: This is the only place we take the ownership of the fd of the authfs service.
- let socket_fd = unsafe { prepare_authfs_service_socket()? };
+ let socket_fd = android_get_control_socket(AUTHFS_SERVICE_SOCKET_NAME)?;
let service = AuthFsService::new_binder(debuggable).as_binder();
debug!("{} is starting as a rpc service.", AUTHFS_SERVICE_SOCKET_NAME);
let server = RpcServer::new_bound_socket(service, socket_fd)?;