Use rustix for prctl (#1333)

userspace/ksud/Cargo.lock

@@ -859,7 +859,7 @@ dependencies = [
  "regex",
  "retry",
  "rust-embed",
- "rustix 0.38.30",
+ "rustix 0.38.30 (git+https://github.com/Kernel-SU/rustix.git)",
  "serde",
  "serde_json",
  "sha256",
@@ -1155,7 +1155,7 @@ dependencies = [
  "hex",
  "lazy_static",
  "procfs-core",
- "rustix 0.38.30",
+ "rustix 0.38.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1374,6 +1374,18 @@ name = "rustix"
 version = "0.38.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "322394588aaf33c24007e8bb3238ee3e4c5c09c084ab32bc73890b99ff326bca"
+dependencies = [
+ "bitflags 2.4.1",
+ "errno 0.3.8",
+ "libc",
+ "linux-raw-sys 0.4.13",
+ "windows-sys 0.52.0",
+]
+
+[[package]]
+name = "rustix"
+version = "0.38.30"
+source = "git+https://github.com/Kernel-SU/rustix.git#cea95a423076be6a793679773fb4e80a3e40f38c"
 dependencies = [
  "bitflags 2.4.1",
  "errno 0.3.8",
@@ -1690,7 +1702,7 @@ dependencies = [
  "either",
  "home",
  "once_cell",
- "rustix 0.38.30",
+ "rustix 0.38.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "windows-sys 0.48.0",
 ]
 

userspace/ksud/Cargo.toml

@@ -39,7 +39,7 @@ chrono = "0.4"
 hole-punch = { git = "https://github.com/tiann/hole-punch" }
 
 [target.'cfg(any(target_os = "android", target_os = "linux"))'.dependencies]
-rustix = { version = "0.38", features = ["all-apis"] }
+rustix = { git = "https://github.com/Kernel-SU/rustix.git", 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"

userspace/ksud/src/ksu.rs

@@ -1,7 +1,4 @@
 use anyhow::{Ok, Result};
-
-#[cfg(unix)]
-use anyhow::ensure;
 use getopts::Options;
 use std::env;
 #[cfg(unix)]
@@ -20,39 +17,14 @@ use rustix::{
     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;
-// const CMD_BECOME_MANAGER: u64 = 1;
-const CMD_GET_VERSION: u64 = 2;
-// const CMD_ALLOW_SU: u64 = 3;
-// const CMD_DENY_SU: u64 = 4;
-// const CMD_GET_ALLOW_LIST: u64 = 5;
-// const CMD_GET_DENY_LIST: u64 = 6;
-const CMD_REPORT_EVENT: u64 = 7;
-pub const CMD_SET_SEPOLICY: u64 = 8;
-pub const CMD_CHECK_SAFEMODE: u64 = 9;
-
 const EVENT_POST_FS_DATA: u64 = 1;
 const EVENT_BOOT_COMPLETED: u64 = 2;
 const EVENT_MODULE_MOUNTED: u64 = 3;
 
 #[cfg(any(target_os = "linux", target_os = "android"))]
 pub fn grant_root() -> Result<()> {
-    let mut result: u32 = 0;
+    rustix::process::ksu_grant_root()?;
-    unsafe {
+    Ok(())
-        #[allow(clippy::cast_possible_wrap)]
-        libc::prctl(
-            KERNEL_SU_OPTION as i32, // supposed to overflow
-            CMD_GRANT_ROOT,
-            0,
-            0,
-            std::ptr::addr_of_mut!(result).cast::<libc::c_void>(),
-        );
-    }
-
-    ensure!(result == KERNEL_SU_OPTION, "grant root failed");
-    Err(std::process::Command::new("sh").exec().into())
 }
 
 #[cfg(not(any(target_os = "linux", target_os = "android")))]
@@ -302,46 +274,32 @@ fn add_path_to_env(path: &str) -> Result<()> {
     Ok(())
 }
 
+#[cfg(any(target_os = "linux", target_os = "android"))]
 pub fn get_version() -> i32 {
-    let mut result: i32 = 0;
+    rustix::process::ksu_get_version()
-    #[cfg(any(target_os = "linux", target_os = "android"))]
-    unsafe {
-        #[allow(clippy::cast_possible_wrap)]
-        libc::prctl(
-            KERNEL_SU_OPTION as i32, // supposed to overflow
-            CMD_GET_VERSION,
-            std::ptr::addr_of_mut!(result).cast::<libc::c_void>(),
-        );
-    }
-    result
 }
 
+#[cfg(not(any(target_os = "linux", target_os = "android")))]
+pub fn get_version() -> i32 {
+    0
+}
+
+#[cfg(any(target_os = "linux", target_os = "android"))]
 fn report_event(event: u64) {
-    #[cfg(any(target_os = "linux", target_os = "android"))]
+    rustix::process::ksu_report_event(event)
-    unsafe {
-        #[allow(clippy::cast_possible_wrap)]
-        libc::prctl(
-            KERNEL_SU_OPTION as i32, // supposed to overflow
-            CMD_REPORT_EVENT,
-            event,
-        );
-    }
 }
 
+#[cfg(not(any(target_os = "linux", target_os = "android")))]
+fn report_event(_event: u64) {}
+
+#[cfg(any(target_os = "linux", target_os = "android"))]
 pub fn check_kernel_safemode() -> bool {
-    let mut result: i32 = 0;
+    rustix::process::ksu_check_kernel_safemode()
-    #[cfg(any(target_os = "linux", target_os = "android"))]
+}
-    unsafe {
+
-        #[allow(clippy::cast_possible_wrap)]
+#[cfg(not(any(target_os = "linux", target_os = "android")))]
-        libc::prctl(
+pub fn check_kernel_safemode() -> bool {
-            KERNEL_SU_OPTION as i32, // supposed to overflow
+    false
-            CMD_CHECK_SAFEMODE,
-            0,
-            0,
-            std::ptr::addr_of_mut!(result).cast::<libc::c_void>(),
-        );
-    }
-    result == KERNEL_SU_OPTION as i32
 }
 
 pub fn report_post_fs_data() {

userspace/ksud/src/sepolicy.rs

@@ -696,20 +696,7 @@ fn apply_one_rule<'a>(statement: &'a PolicyStatement<'a>, strict: bool) -> Resul
     let policies: Vec<AtomicStatement> = statement.try_into()?;
 
     for policy in policies {
-        let mut result: u32 = 0;
+        if !rustix::process::ksu_set_policy(&FfiPolicy::from(policy)) {
-        let cpolicy = FfiPolicy::from(policy);
-        unsafe {
-            #[allow(clippy::cast_possible_wrap)]
-            libc::prctl(
-                crate::ksu::KERNEL_SU_OPTION as i32, // supposed to overflow
-                crate::ksu::CMD_SET_SEPOLICY,
-                0,
-                std::ptr::addr_of!(cpolicy).cast::<libc::c_void>(),
-                std::ptr::addr_of_mut!(result).cast::<libc::c_void>(),
-            );
-        }
-
-        if result != crate::ksu::KERNEL_SU_OPTION {
             log::warn!("apply rule: {:?} failed.", statement);
             if strict {
                 return Err(anyhow::anyhow!("apply rule {:?} failed.", statement));