Merge pull request containers#604 from cgwalters/to-existing-root-dou…

…ble-warn

install: Move warning after state and possible re-exec

lib/src/install.rs

@@ -1442,14 +1442,18 @@ pub(crate) async fn install_to_filesystem(
  anyhow::bail!("Not a mountpoint: {root_path}");
  }
 
+ // Gather global state, destructuring the provided options.
+ // IMPORTANT: We might re-execute the current process in this function (for SELinux among other things)
+ // IMPORTANT: and hence anything that is done before MUST BE IDEMPOTENT.
+ // IMPORTANT: In practice, we should only be gathering information before this point,
+ // IMPORTANT: and not performing any mutations at all.
+ let state = prepare_install(opts.config_opts, opts.source_opts, opts.target_opts).await?;
+
  // Check to see if this happens to be the real host root
  if !fsopts.acknowledge_destructive {
  warn_on_host_root(&rootfs_fd)?;
  }
 
- // Gather global state, destructuring the provided options
- let state = prepare_install(opts.config_opts, opts.source_opts, opts.target_opts).await?;
-
  match fsopts.replace {
  Some(ReplaceMode::Wipe) => {
  let rootfs_fd = rootfs_fd.try_clone()?;