Merge pull request #1325 from tiann/rustix

Author: yujincheng08

userspace/ksud/Cargo.lock

@@ -39,10 +39,11 @@ chrono = "0.4"
 hole-punch = { git = "https://github.com/tiann/hole-punch" }
 
 [target.'cfg(any(target_os = "android", target_os = "linux"))'.dependencies]
-sys-mount = { git = "https://github.com/tiann/sys-mount", branch = "loopfix" }
+rustix = { version = "0.38", features = ["all-apis"] }
 # some android specific dependencies which compiles under unix are also listed here for convenience of coding
 android-properties = { version = "0.2.2", features = ["bionic-deprecated"] }
 procfs = "0.16"
+loopdev = { git = "https://github.com/tiann/loopdev", branch = "loopfix" }
 
 [target.'cfg(target_os = "android")'.dependencies]
 android_logger = "0.13"

userspace/ksud/Cargo.toml

@@ -1,5 +1,6 @@
 use anyhow::{bail, Context, Result};
 use log::{info, warn};
+#[cfg(target_os = "android")]
 use std::path::PathBuf;
 use std::{collections::HashMap, path::Path};
 

userspace/ksud/src/event.rs

@@ -14,6 +14,12 @@ use crate::{
     utils::{self, umask},
 };
 
+#[cfg(any(target_os = "linux", target_os = "android"))]
+use rustix::{
+    process::getuid,
+    thread::{set_thread_res_gid, set_thread_res_uid, Gid, Uid},
+};
+
 pub const KERNEL_SU_OPTION: u32 = 0xDEAD_BEEF;
 
 const CMD_GRANT_ROOT: u64 = 0;
@@ -65,8 +71,13 @@ fn set_identity(uid: u32, gid: u32, groups: &[u32]) {
         if !groups.is_empty() {
             libc::setgroups(groups.len(), groups.as_ptr());
         }
-        libc::setresgid(gid, gid, gid);
-        libc::setresuid(uid, uid, uid);
+    }
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    {
+        let gid = unsafe { Gid::from_raw(gid) };
+        let uid = unsafe { Uid::from_raw(uid) };
+        set_thread_res_gid(gid, gid, gid).ok();
+        set_thread_res_uid(uid, uid, uid).ok();
     }
 }
 
@@ -203,7 +214,7 @@ pub fn root_shell() -> Result<()> {
     }
 
     // use current uid if no user specified, these has been done in kernel!
-    let mut uid = unsafe { libc::getuid() };
+    let mut uid = getuid().as_raw();
     if free_idx < matches.free.len() {
         let name = &matches.free[free_idx];
         uid = unsafe {