Add --uid --gid options to zipfuse
So far, files and directories in a zipfuse filesystem had root as its
uid/gid. This change adds two options --uid and --gid to zipfuse which
are used to override the behavior.
For now, microdroid_manager uses `--uid 0 --gid 0` which means there's
no behavioral change. A follow-up change will set the IDs to a non-root
value.
Bug: 264668376
Test: run microdroid tests
Change-Id: I935424a52edcc3868fdf6aef526a641855a67f63
diff --git a/microdroid_manager/src/main.rs b/microdroid_manager/src/main.rs
index 4018d00..1ef41cb 100644
--- a/microdroid_manager/src/main.rs
+++ b/microdroid_manager/src/main.rs
@@ -488,6 +488,8 @@
}
impl Zipfuse {
+ const MICRODROID_PAYLOAD_UID: u32 = 0; // TODO(b/264861173) should be non-root
+ const MICRODROID_PAYLOAD_GID: u32 = 0; // TODO(b/264861173) should be non-root
fn mount(
&mut self,
noexec: MountForExec,
@@ -501,6 +503,8 @@
cmd.arg("--noexec");
}
cmd.args(["-p", &ready_prop, "-o", option]);
+ cmd.args(["-u", &Self::MICRODROID_PAYLOAD_UID.to_string()]);
+ cmd.args(["-g", &Self::MICRODROID_PAYLOAD_GID.to_string()]);
cmd.arg(zip_path).arg(mount_dir);
self.ready_properties.push(ready_prop);
cmd.spawn().with_context(|| format!("Failed to run zipfuse for {mount_dir:?}"))
diff --git a/zipfuse/src/main.rs b/zipfuse/src/main.rs
index fd7e414..ffa0a4a 100644
--- a/zipfuse/src/main.rs
+++ b/zipfuse/src/main.rs
@@ -59,6 +59,18 @@
.takes_value(true)
.help("Specify a property to be set when mount is ready"),
)
+ .arg(
+ Arg::with_name("uid")
+ .short('u')
+ .takes_value(true)
+ .help("numeric UID who's the owner of the files"),
+ )
+ .arg(
+ Arg::with_name("gid")
+ .short('g')
+ .takes_value(true)
+ .help("numeric GID who's the group of the files"),
+ )
.arg(Arg::with_name("ZIPFILE").required(true))
.arg(Arg::with_name("MOUNTPOINT").required(true))
.get_matches();
@@ -68,7 +80,9 @@
let options = matches.value_of("options");
let noexec = matches.is_present("noexec");
let ready_prop = matches.value_of("readyprop");
- run_fuse(zip_file, mount_point, options, noexec, ready_prop)?;
+ let uid: u32 = matches.value_of("uid").map_or(0, |s| s.parse().unwrap());
+ let gid: u32 = matches.value_of("gid").map_or(0, |s| s.parse().unwrap());
+ run_fuse(zip_file, mount_point, options, noexec, ready_prop, uid, gid)?;
Ok(())
}
@@ -79,6 +93,8 @@
extra_options: Option<&str>,
noexec: bool,
ready_prop: Option<&str>,
+ uid: u32,
+ gid: u32,
) -> Result<()> {
const MAX_READ: u32 = 1 << 20; // TODO(jiyong): tune this
const MAX_WRITE: u32 = 1 << 13; // This is a read-only filesystem
@@ -111,7 +127,7 @@
let mut config = fuse::FuseConfig::new();
config.dev_fuse(dev_fuse).max_write(MAX_WRITE).max_read(MAX_READ);
- Ok(config.enter_message_loop(ZipFuse::new(zip_file)?)?)
+ Ok(config.enter_message_loop(ZipFuse::new(zip_file, uid, gid)?)?)
}
struct ZipFuse {
@@ -120,6 +136,8 @@
inode_table: InodeTable,
open_files: Mutex<HashMap<Handle, OpenFile>>,
open_dirs: Mutex<HashMap<Handle, OpenDirBuf>>,
+ uid: u32,
+ gid: u32,
}
/// Represents a [`ZipFile`] that is opened.
@@ -152,7 +170,7 @@
}
impl ZipFuse {
- fn new(zip_file: &Path) -> Result<ZipFuse> {
+ fn new(zip_file: &Path, uid: u32, gid: u32) -> Result<ZipFuse> {
// TODO(jiyong): Use O_DIRECT to avoid double caching.
// `.custom_flags(nix::fcntl::OFlag::O_DIRECT.bits())` currently doesn't work.
let f = File::open(zip_file)?;
@@ -167,6 +185,8 @@
inode_table: it,
open_files: Mutex::new(HashMap::new()),
open_dirs: Mutex::new(HashMap::new()),
+ uid,
+ gid,
})
}
@@ -189,8 +209,8 @@
st.st_ino = inode;
st.st_mode = if inode_data.is_dir() { libc::S_IFDIR } else { libc::S_IFREG };
st.st_mode |= inode_data.mode;
- st.st_uid = 0;
- st.st_gid = 0;
+ st.st_uid = self.uid;
+ st.st_gid = self.gid;
st.st_size = i64::try_from(inode_data.size).unwrap_or(i64::MAX);
Ok(st)
}
@@ -466,7 +486,7 @@
let zip_path = PathBuf::from(zip_path);
let mnt_path = PathBuf::from(mnt_path);
std::thread::spawn(move || {
- crate::run_fuse(&zip_path, &mnt_path, None, noexec).unwrap();
+ crate::run_fuse(&zip_path, &mnt_path, None, noexec, 0, 0).unwrap();
});
}