Fix race

zygiskd/src/main.rs

@@ -43,7 +43,7 @@ fn main() {
     let cli = Args::parse();
     let result = match cli.command {
         Commands::Watchdog => watchdog::entry(),
-        Commands::Daemon => zygiskd::entry(lp_select!(false, true)),
+        Commands::Daemon => zygiskd::entry(),
         Commands::Companion { fd } => companion::entry(fd),
     };
 

zygiskd/src/watchdog.rs

@@ -1,4 +1,4 @@
-use crate::constants;
+use crate::{constants, utils};
 use anyhow::{bail, Result};
 use nix::fcntl::{flock, FlockArg};
 use nix::unistd::{getgid, getuid};
@@ -6,6 +6,8 @@ use std::os::unix::prelude::AsRawFd;
 use std::process::{Child, Command};
 use std::sync::mpsc;
 use std::{fs, thread};
+use std::path::Path;
+use std::time::Duration;
 
 static mut LOCK_FILE: Option<fs::File> = None;
 
@@ -61,7 +63,9 @@ fn spawn_daemon() -> Result<()> {
     let daemon32 = Command::new(constants::PATH_ZYGISKD32).arg("daemon").spawn();
     let daemon64 = Command::new(constants::PATH_ZYGISKD64).arg("daemon").spawn();
     let (sender, receiver) = mpsc::channel();
-    let spawn = |mut daemon: Child| {
+    let mut waiting = vec![];
+    let mut spawn = |mut daemon: Child, socket: &'static str| {
+        waiting.push(socket);
         let sender = sender.clone();
         thread::spawn(move || {
             let result = daemon.wait().unwrap();
@@ -70,8 +74,22 @@ fn spawn_daemon() -> Result<()> {
             sender.send(()).unwrap();
         });
     };
-    if let Ok(it) = daemon32 { spawn(it) }
+    if let Ok(it) = daemon32 { spawn(it, "/dev/socket/zygote_secondary") }
-    if let Ok(it) = daemon64 { spawn(it) }
+    if let Ok(it) = daemon64 { spawn(it, "/dev/socket/zygote") }
+
+    waiting.into_iter().for_each(|socket| wait_zygote(socket));
+    log::info!("Zygote ready, restore native bridge");
+    utils::restore_native_bridge()?;
+
     let _ = receiver.recv();
     bail!("Daemon process died");
 }
+
+fn wait_zygote(socket: &str) -> () {
+    let path = Path::new(socket);
+    loop {
+        if path.exists() { return; }
+        log::debug!("{socket} not exists, wait for 1s...");
+        thread::sleep(Duration::from_secs(1));
+    }
+}

zygiskd/src/zygiskd.rs

@@ -1,6 +1,6 @@
 use crate::constants::DaemonSocketAction;
-use crate::utils::{restore_native_bridge, UnixStreamExt};
+use crate::utils::UnixStreamExt;
-use crate::{constants, utils};
+use crate::{constants, lp_select, utils};
 use anyhow::{bail, Result};
 use memfd::Memfd;
 use nix::{
@@ -31,10 +31,10 @@ struct Context {
     modules: Vec<Module>,
 }
 
-pub fn entry(is64: bool) -> Result<()> {
+pub fn entry() -> Result<()> {
     unsafe { libc::prctl(libc::PR_SET_PDEATHSIG, libc::SIGKILL) };
 
-    let arch = get_arch(is64)?;
+    let arch = get_arch()?;
     log::debug!("Daemon architecture: {arch}");
 
     log::info!("Load modules");
@@ -47,7 +47,7 @@ pub fn entry(is64: bool) -> Result<()> {
     let context = Arc::new(context);
 
     log::info!("Create socket");
-    let listener = create_daemon_socket(is64)?;
+    let listener = create_daemon_socket()?;
 
     log::info!("Handle zygote connections");
     for stream in listener.incoming() {
@@ -63,18 +63,16 @@ pub fn entry(is64: bool) -> Result<()> {
     Ok(())
 }
 
-fn get_arch(is64: bool) -> Result<&'static str> {
+fn get_arch() -> Result<&'static str> {
     let output = Command::new("getprop").arg("ro.product.cpu.abi").output()?;
     let system_arch = String::from_utf8(output.stdout)?;
-    let is_arm = system_arch.contains("arm");
+    if system_arch.contains("arm") {
-    let is_x86 = system_arch.contains("x86");
+        return Ok(lp_select!("armeabi-v7a", "arm64-v8a"))
-    match (is_arm, is_x86, is64) {
-        (true, _, false) => Ok("armeabi-v7a"),
-        (true, _, true) => Ok("arm64-v8a"),
-        (_, true, false) => Ok("x86"),
-        (_, true, true) => Ok("x86_64"),
-        _ => bail!("Unsupported system architecture: {}", system_arch),
     }
+    if system_arch.contains("x86") {
+        return Ok(lp_select!("x86", "x86_64"))
+    }
+    bail!("Unsupported system architecture: {}", system_arch);
 }
 
 fn load_modules(arch: &str) -> Result<Vec<Module>> {
@@ -137,9 +135,9 @@ fn create_memfd(name: &str, so_path: &PathBuf) -> Result<Memfd> {
     Ok(memfd)
 }
 
-fn create_daemon_socket(is64: bool) -> Result<UnixListener> {
+fn create_daemon_socket() -> Result<UnixListener> {
     utils::set_socket_create_context("u:r:zygote:s0")?;
-    let suffix = if is64 { "zygiskd64" } else { "zygiskd32" };
+    let suffix = lp_select!("zygiskd32", "zygiskd64");
     let name = String::from(suffix) + constants::SOCKET_PLACEHOLDER;
     let listener = utils::abstract_namespace_socket(&name)?;
     log::debug!("Daemon socket: {name}");
@@ -175,7 +173,7 @@ fn handle_daemon_action(mut stream: UnixStream, context: &Context) -> Result<()>
     log::trace!("New daemon action {:?}", action);
     match action {
         DaemonSocketAction::PingHeartbeat => {
-            restore_native_bridge()?;
+            // Do nothing
         }
         DaemonSocketAction::RequestLogcatFd => {
             loop {