Skip to content

Clear special bits when hardening Windows VM dirs #12019

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
ram-devv1 wants to merge 1 commit into from
Closed

Clear special bits when hardening Windows VM dirs #12019

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 13 additions & 1 deletion bin/omarchy-windows-vm
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -580,14 +580,24 @@ prepare_caller_mounts() {
# Privacy is an explicit preflight step for both already-pinned sources, not
# a side effect halfway through the two-mount transaction. Old umask-022
# installs are hardened together before either Docker-facing anchor changes.
# NOTE: numeric chmod preserves setuid/setgid on directories (see man chmod
# SETUID AND SETGID BITS), so a 2700 source survives a bare `chmod 0700`.
# Clear the special bits explicitly, otherwise the == 700 check below fails
# closed forever (e.g. ~/Windows inheriting setgid from the VM's Samba share).
chmod 0700 -- "/proc/$BASHPID/fd/$storage_fd" "/proc/$BASHPID/fd/$shared_fd" || {
exec {storage_fd}<&-
exec {shared_fd}<&-
return 1
}
chmod u-s,g-s -- "/proc/$BASHPID/fd/$storage_fd" "/proc/$BASHPID/fd/$shared_fd" || {
exec {storage_fd}<&-
exec {shared_fd}<&-
return 1
}
storage_mode=$(stat -Lc '%a' "/proc/$BASHPID/fd/$storage_fd" 2>/dev/null) || storage_mode=""
shared_mode=$(stat -Lc '%a' "/proc/$BASHPID/fd/$shared_fd" 2>/dev/null) || shared_mode=""
if [[ $storage_mode != 700 || $shared_mode != 700 ]]; then
echo "omarchy-windows-vm: VM directories must be private (mode 0700): storage=$storage_mode shared=$shared_mode" >&2
exec {storage_fd}<&-
exec {shared_fd}<&-
return 1
Expand Down Expand Up @@ -1015,7 +1025,9 @@ prepare_user_mount_sources() {
echo "omarchy-windows-vm: storage and shared must be different directories" >&2
return 1
}
chmod 0700 -- "$storage" "$shared"
# Numeric chmod alone preserves setuid/setgid on directories, so clear the
# special bits explicitly (see prepare_caller_mounts).
chmod 0700 -- "$storage" "$shared" && chmod u-s,g-s -- "$storage" "$shared"
}

storage_space_path() {
Expand Down