runk: Handle rootfs path in config.json properly

This commit enables runk to handle `root.path` in `config.json`
properly even if the path is specified by a relative path that
includes the single (`.`) or the double (`..`) dots.
For example, with a bundle at `/to/bundle` and a rootfs directly
under `/to/bundle` such as `/to/bundle/{bin,dev,etc,home,...}`,
the `root.path` value can be either `/to/bundle` or just `.`.
This behavior conforms to OCI runtime spec.
Accordingly, a bundle path managed by runk's status file
(`status.json`) always is statically stored as a canonical path.
Previously, a bundle path has been　got by `oci_state()` of rustjail's
API that returns the path as the parent directory path of a rootfs
(`root.path`). In case of the kata-agent, this works properly because
the kata containers assume that the rootfs path is always
`/to/bundle/rootfs`. However in case of standard OCI runtimes,
a rootfs can be placed anywhere under a bundle, so the rootfs path
doesn't always have to be at a `/to/bundle/rootfs`.

Fixes: #4334

Signed-off-by: Manabu Sugimoto <Manabu.Sugimoto@sony.com>

src/tools/runk/libcontainer/src/builder.rs

@@ -37,20 +37,20 @@ impl Container {
             // If the rootfs path in the spec file is a relative path,
             // convert it into a canonical path to pass validation of rootfs in the agent.
             if !&rootfs_path.is_absolute() {
-                let rootfs_name = rootfs_path
-                    .file_name()
-                    .ok_or_else(|| anyhow!("invalid rootfs name"))?;
                 spec_root.path = bundle_canon
-                    .join(rootfs_name)
+                    .join(rootfs_path)
+                    .canonicalize()?
                     .to_str()
                     .map(|s| s.to_string())
-                    .ok_or_else(|| anyhow!("failed to convert bundle path"))?;
+                    .ok_or_else(|| {
+                        anyhow!("failed to convert a rootfs path into a canonical path")
+                    })?;
             }
         }
 
         Ok(ContainerContext {
             id: self.id,
-            bundle: self.bundle,
+            bundle: bundle_canon,
             state_root: self.root,
             spec,
             // TODO: liboci-cli does not support --no-pivot option for create and run command.

src/tools/runk/libcontainer/src/container.rs

@@ -95,6 +95,7 @@ impl ContainerContext {
         let oci_state = ctr.oci_state()?;
         let status = Status::new(
             &self.state_root,
+            &self.bundle,
             oci_state,
             ctr.init_process_start_time,
             ctr.created,
@@ -141,7 +142,7 @@ mod tests {
 
     #[test]
     fn test_get_fifo_path() {
-        let test_data = PathBuf::from(TEST_BUNDLE_PATH)
+        let test_data = PathBuf::from(TEST_STATE_ROOT_PATH)
             .join(TEST_CONTAINER_ID)
             .join(EXEC_FIFO_FILENAME);
         let status = create_dummy_status();

src/tools/runk/libcontainer/src/status.rs

@@ -42,6 +42,7 @@ pub struct Status {
 impl Status {
     pub fn new(
         root: &Path,
+        bundle: &Path,
         oci_state: OCIState,
         process_start_time: u64,
         created_time: SystemTime,
@@ -64,7 +65,7 @@ impl Status {
             id: oci_state.id,
             pid: oci_state.pid,
             root: root.to_path_buf(),
-            bundle: PathBuf::from(&oci_state.bundle),
+            bundle: bundle.to_path_buf(),
             rootfs,
             process_start_time,
             created,
@@ -209,6 +210,7 @@ mod tests {
         let oci_state = create_dummy_oci_state();
         let created = SystemTime::now();
         let status = Status::new(
+            Path::new(TEST_STATE_ROOT_PATH),
             Path::new(TEST_BUNDLE_PATH),
             oci_state.clone(),
             1,

src/tools/runk/libcontainer/src/utils.rs

@@ -45,7 +45,8 @@ pub(crate) mod test_utils {
     use std::time::SystemTime;
 
     pub const TEST_CONTAINER_ID: &str = "test";
-    pub const TEST_BUNDLE_PATH: &str = "/test";
+    pub const TEST_STATE_ROOT_PATH: &str = "/state";
+    pub const TEST_BUNDLE_PATH: &str = "/bundle";
     pub const TEST_ANNOTATION: &str = "test";
     pub const TEST_CGM_DATA: &str = r#"{
         "paths": {
@@ -92,6 +93,7 @@ pub(crate) mod test_utils {
         let oci_state = create_dummy_oci_state();
         let created = SystemTime::now();
         let status = Status::new(
+            Path::new(TEST_STATE_ROOT_PATH),
             Path::new(TEST_BUNDLE_PATH),
             oci_state.clone(),
             1,