Merge "Remove yet another use of from_raw_fd" into main
diff --git a/guest/authfs_service/Android.bp b/guest/authfs_service/Android.bp
index 2101a36..e508c17 100644
--- a/guest/authfs_service/Android.bp
+++ b/guest/authfs_service/Android.bp
@@ -18,6 +18,7 @@
         "libnix",
         "librpcbinder_rs",
         "librustutils",
+        "libsafe_ownedfd",
         "libshared_child",
     ],
     prefer_rlib: true,
diff --git a/guest/authfs_service/src/main.rs b/guest/authfs_service/src/main.rs
index 97e684d..ff2f770 100644
--- a/guest/authfs_service/src/main.rs
+++ b/guest/authfs_service/src/main.rs
@@ -26,9 +26,10 @@
 use log::*;
 use rpcbinder::RpcServer;
 use rustutils::sockets::android_get_control_socket;
+use safe_ownedfd::take_fd_ownership;
 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::os::unix::io::OwnedFd;
 use std::sync::atomic::{AtomicUsize, Ordering};
 
 use authfs_aidl_interface::aidl::com::android::virt::fs::AuthFsConfig::AuthFsConfig;
@@ -109,22 +110,9 @@
 }
 
 /// 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> {
+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) })
+    Ok(take_fd_ownership(raw_fd)?)
 }
 
 #[allow(clippy::eq_op)]
@@ -137,8 +125,7 @@
 
     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 = prepare_authfs_service_socket()?;
     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)?;