Use new mount api

userspace/ksud/Cargo.lock

@@ -853,6 +853,7 @@ dependencies = [
  "jwalk",
  "libc",
  "log",
+ "loopdev",
  "nom",
  "procfs",
  "regex",
@@ -862,7 +863,6 @@ dependencies = [
  "serde",
  "serde_json",
  "sha256",
- "sys-mount",
  "tempdir",
  "which",
  "zip 0.6.4",
@@ -1463,17 +1463,6 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
-[[package]]
-name = "smart-default"
-version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "133659a15339456eeeb07572eb02a91c91e9815e9cbc89566944d2c8d3efdbf6"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 1.0.107",
-]
-
 [[package]]
 name = "strsim"
 version = "0.10.0"
@@ -1508,19 +1497,6 @@ dependencies = [
  "unicode-ident",
 ]
 
-[[package]]
-name = "sys-mount"
-version = "2.0.2"
-source = "git+https://github.com/tiann/sys-mount?branch=loopfix#c7c4048e4a4ffdf8b108a85956363a75f2c554f0"
-dependencies = [
- "bitflags 1.3.2",
- "libc",
- "loopdev",
- "smart-default",
- "thiserror",
- "tracing",
-]
-
 [[package]]
 name = "tempdir"
 version = "0.3.7"
@@ -1599,37 +1575,6 @@ dependencies = [
  "pin-project-lite",
 ]
 
-[[package]]
-name = "tracing"
-version = "0.1.40"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3523ab5a71916ccf420eebdf5521fcef02141234bbc0b8a49f2fdc4544364ef"
-dependencies = [
- "pin-project-lite",
- "tracing-attributes",
- "tracing-core",
-]
-
-[[package]]
-name = "tracing-attributes"
-version = "0.1.27"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "34704c8d6ebcbc939824180af020566b01a7c01f80641264eba0999f6c2b6be7"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.48",
-]
-
-[[package]]
-name = "tracing-core"
-version = "0.1.32"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c06d3da6113f116aaee68e4d601191614c9053067f9ab7f6edbcb161237daa54"
-dependencies = [
- "once_cell",
-]
-
 [[package]]
 name = "typenum"
 version = "1.16.0"

userspace/ksud/Cargo.toml

@@ -39,11 +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/src/event.rs

@@ -1,5 +1,7 @@
 use anyhow::{bail, Context, Result};
 use log::{info, warn};
+#[cfg(target_os = "android")]
+use std::path::PathBuf;
 use std::{collections::HashMap, path::Path};
 
 use crate::module::prune_modules;

userspace/ksud/src/mount.rs

@@ -1,11 +1,11 @@
-use anyhow::{bail, Ok, Result};
+use anyhow::{anyhow, bail, Ok, Result};
 
 #[cfg(any(target_os = "linux", target_os = "android"))]
 use anyhow::Context;
 #[cfg(any(target_os = "linux", target_os = "android"))]
 use retry::delay::NoDelay;
 #[cfg(any(target_os = "linux", target_os = "android"))]
-use sys_mount::{unmount, FilesystemType, Mount, MountFlags, Unmount, UnmountFlags};
+use rustix::{fd::AsFd, fs::CWD, mount::*};
 
 use crate::defs::KSU_OVERLAY_SOURCE;
 use log::{info, warn};
@@ -14,49 +14,32 @@ use procfs::process::Process;
 use std::path::Path;
 
 pub struct AutoMountExt4 {
-    mnt: String,
+    target: String,
-    #[cfg(any(target_os = "linux", target_os = "android"))]
-    mount: Option<Mount>,
     auto_umount: bool,
 }
 
 impl AutoMountExt4 {
     #[cfg(any(target_os = "linux", target_os = "android"))]
-    pub fn try_new(src: &str, mnt: &str, auto_umount: bool) -> Result<Self> {
+    pub fn try_new(source: &str, target: &str, auto_umount: bool) -> Result<Self> {
-        let result = Mount::builder()
+        let new_loopback = loopdev::LoopControl::open()?.next_free()?;
-            .fstype(FilesystemType::from("ext4"))
+        new_loopback.with().attach(source)?;
-            .flags(MountFlags::empty())
+        let lo = new_loopback.path().ok_or(anyhow!("no loop"))?;
-            .create_loop(true)
+        let fs = fsopen("ext4", FsOpenFlags::FSOPEN_CLOEXEC)?;
-            .mount(src, mnt)
+        let fs = fs.as_fd();
-            .map(|mount| {
+        fsconfig_set_string(fs, "source", lo)?;
-                Ok(Self {
+        fsconfig_create(fs)?;
-                    mnt: mnt.to_string(),
+        let mount = fsmount(fs, FsMountFlags::FSMOUNT_CLOEXEC, MountAttrFlags::empty())?;
-                    mount: Some(mount),
+        move_mount(
-                    auto_umount,
+            mount.as_fd(),
-                })
+            "",
-            });
+            CWD,
-        if let Err(e) = result {
+            target,
-            println!("- Mount failed: {e}, retry with system mount");
+            MoveMountFlags::MOVE_MOUNT_F_EMPTY_PATH,
-            let result = std::process::Command::new("mount")
+        )?;
-                .arg("-t")
+        Ok(Self {
-                .arg("ext4")
+            target: target.to_string(),
-                .arg(src)
+            auto_umount,
-                .arg(mnt)
+        })
-                .status();
-            if let Err(e) = result {
-                Err(anyhow::anyhow!(
-                    "mount partition: {src} -> {mnt} failed: {e}"
-                ))
-            } else {
-                Ok(Self {
-                    mnt: mnt.to_string(),
-                    mount: None,
-                    auto_umount,
-                })
-            }
-        } else {
-            result.unwrap()
-        }
     }
 
     #[cfg(not(any(target_os = "linux", target_os = "android")))]
@@ -66,18 +49,8 @@ impl AutoMountExt4 {
 
     #[cfg(any(target_os = "linux", target_os = "android"))]
     pub fn umount(&self) -> Result<()> {
-        if let Some(ref mount) = self.mount {
+        unmount(self.target.as_str(), UnmountFlags::DETACH)?;
-            mount
+        Ok(())
-                .unmount(UnmountFlags::empty())
-                .map_err(|e| anyhow::anyhow!(e))
-        } else {
-            let result = std::process::Command::new("umount").arg(&self.mnt).status();
-            if let Err(e) = result {
-                Err(anyhow::anyhow!("umount: {} failed: {e}", self.mnt))
-            } else {
-                Ok(())
-            }
-        }
     }
 }
 
@@ -86,7 +59,7 @@ impl Drop for AutoMountExt4 {
     fn drop(&mut self) {
         log::info!(
             "AutoMountExt4 drop: {}, auto_umount: {}",
-            self.mnt,
+            self.target,
             self.auto_umount
         );
         if self.auto_umount {
@@ -98,18 +71,7 @@ impl Drop for AutoMountExt4 {
 #[allow(dead_code)]
 #[cfg(any(target_os = "linux", target_os = "android"))]
 fn mount_image(src: &str, target: &str, autodrop: bool) -> Result<()> {
-    if autodrop {
+    AutoMountExt4::try_new(src, target, autodrop)?;
-        Mount::builder()
-            .fstype(FilesystemType::from("ext4"))
-            .create_loop(true)
-            .mount_autodrop(src, target, UnmountFlags::empty())
-            .with_context(|| format!("Failed to do mount: {src} -> {target}"))?;
-    } else {
-        Mount::builder()
-            .fstype(FilesystemType::from("ext4"))
-            .mount(src, target)
-            .with_context(|| format!("Failed to do mount: {src} -> {target}"))?;
-    }
     Ok(())
 }
 
@@ -146,28 +108,37 @@ fn mount_overlayfs(
         dest.as_ref().display(),
         options
     );
-    Mount::builder()
+    let fs = fsopen("overlay", FsOpenFlags::FSOPEN_CLOEXEC)?;
-        .fstype(FilesystemType::from("overlay"))
+    let fs = fs.as_fd();
-        .data(&options)
+    fsconfig_set_string(fs, "lowerdir", lower_dirs.join(":"))?;
-        .flags(MountFlags::RDONLY)
+    fsconfig_set_string(fs, "source", KSU_OVERLAY_SOURCE)?;
-        .mount(KSU_OVERLAY_SOURCE, dest.as_ref())
+    fsconfig_create(fs)?;
-        .with_context(|| {
+    let mount = fsmount(fs, FsMountFlags::FSMOUNT_CLOEXEC, MountAttrFlags::empty())?;
-            format!(
+    move_mount(
-                "mount overlayfs on {} options {} failed",
+        mount.as_fd(),
-                dest.as_ref().display(),
+        "",
-                options
+        CWD,
-            )
+        dest.as_ref(),
-        })?;
+        MoveMountFlags::MOVE_MOUNT_F_EMPTY_PATH,
+    )?;
     Ok(())
 }
 
 #[cfg(any(target_os = "linux", target_os = "android"))]
 pub fn mount_tmpfs(dest: impl AsRef<Path>) -> Result<()> {
     info!("mount tmpfs on {}", dest.as_ref().display());
-    Mount::builder()
+    let fs = fsopen("tmpfs", FsOpenFlags::FSOPEN_CLOEXEC)?;
-        .fstype(FilesystemType::from("tmpfs"))
+    let fs = fs.as_fd();
-        .mount(KSU_OVERLAY_SOURCE, dest.as_ref())
+    fsconfig_set_string(fs, "source", KSU_OVERLAY_SOURCE)?;
-        .with_context(|| format!("mount tmpfs on {} failed", dest.as_ref().display()))?;
+    fsconfig_create(fs)?;
+    let mount = fsmount(fs, FsMountFlags::FSMOUNT_CLOEXEC, MountAttrFlags::empty())?;
+    move_mount(
+        mount.as_fd(),
+        "",
+        CWD,
+        dest.as_ref(),
+        MoveMountFlags::MOVE_MOUNT_F_EMPTY_PATH,
+    )?;
     Ok(())
 }
 
@@ -178,16 +149,12 @@ fn bind_mount(from: impl AsRef<Path>, to: impl AsRef<Path>) -> Result<()> {
         from.as_ref().display(),
         to.as_ref().display()
     );
-    Mount::builder()
+    let tree = open_tree(
-        .flags(MountFlags::BIND)
+        CWD,
-        .mount(from.as_ref(), to.as_ref())
+        from.as_ref(),
-        .with_context(|| {
+        OpenTreeFlags::OPEN_TREE_CLOEXEC | OpenTreeFlags::OPEN_TREE_CLONE,
-            format!(
+    )?;
-                "bind mount failed: {} -> {}",
+    move_mount(tree.as_fd(), "", CWD, to.as_ref(), MoveMountFlags::empty())?;
-                from.as_ref().display(),
-                to.as_ref().display()
-            )
-        })?;
     Ok(())
 }