Component
mknod
Description
uutils creates the node first, then attempts to set SELinux context. On failure, cleanup uses std::fs::remove_dir, which cannot remove device nodes or FIFOs. GNU sets the file creation context via setfscreatecon before calling mknod, so the node is created with the correct label atomically or not created at all.
// src/uu/mknod/src/mknod.rs:80-105
let errno = libc::mknod(c_str.as_ptr(), config.mode, config.dev);
#[cfg(feature = "selinux")]
if config.set_selinux_context {
if let Err(e) = uucore::selinux::set_selinux_security_context(
std::path::Path::new(file_name),
config.context,
) {
let _ = std::fs::remove_dir(file_name); // <- wrong function for device nodes
eprintln!("{}: {}", uucore::util_name(), e);
return 1;
}
}Test / Reproduction Steps
mknod --context=invalid_context_t /tmp/testnode c 1 3
ls -Z /tmp/testnode
Impact
On SELinux-enforcing systems, the node is created with incorrect default context. The command reports failure but leaves a mislabeled device node behind, potentially allowing unintended access.
Component
mknodDescription
uutils creates the node first, then attempts to set SELinux context. On failure, cleanup uses
std::fs::remove_dir, which cannot remove device nodes or FIFOs. GNU sets the file creation context viasetfscreateconbefore callingmknod, so the node is created with the correct label atomically or not created at all.Test / Reproduction Steps
Impact
On SELinux-enforcing systems, the node is created with incorrect default context. The command reports failure but leaves a mislabeled device node behind, potentially allowing unintended access.