Remove Wine/Proton host filesystem drive mappings and prevent new Z: mappings.

disable-wine-host-drives.sh

#!/usr/bin/env bash
# Remove Wine/Proton host filesystem drive mappings and prevent new Z: mappings.
#
# Usage:
#   ./disable-wine-host-drives.sh
#   ./disable-wine-host-drives.sh --home /home/someuser
#
# Optional:
#   DRY_RUN=1 ./disable-wine-host-drives.sh
#   WINE_GAME_ROOT=/games ./disable-wine-host-drives.sh

set -euo pipefail

target_home="${TARGET_HOME:-$HOME}"

while [ "$#" -gt 0 ]; do
  case "$1" in
    --home)
      target_home="${2:?missing value for --home}"
      shift 2
      ;;
    -h|--help)
      sed -n '1,12p' "$0"
      exit 0
      ;;
    *)
      echo "unknown argument: $1" >&2
      exit 2
      ;;
  esac
done

dry_run="${DRY_RUN:-0}"
bin_dir="$target_home/.local/bin"
game_root="${WINE_GAME_ROOT:-/games}"

run() {
  if [ "$dry_run" = 1 ]; then
    printf 'DRY_RUN:'
    printf ' %q' "$@"
    printf '\n'
  else
    "$@"
  fi
}

write_file() {
  local path=$1
  local tmp
  tmp=$(mktemp)
  cat > "$tmp"
  if [ "$dry_run" = 1 ]; then
    echo "DRY_RUN: write $path"
    rm -f "$tmp"
  else
    install -m 755 "$tmp" "$path"
    rm -f "$tmp"
  fi
}

is_allowed_target() {
  local target=$1
  local resolved_game_root
  local resolved_target

  resolved_game_root=$(readlink -f "$game_root" 2>/dev/null || printf '%s\n' "$game_root")
  resolved_target=$(readlink -f "$target" 2>/dev/null || printf '%s\n' "$target")

  case "$resolved_target" in
    "$resolved_game_root"|"$resolved_game_root"/*) return 0 ;;
  esac

  return 1
}

strip_host_drives() {
  local roots=("$@")
  local root

  [ "$#" -gt 0 ] || roots=("$target_home")

  for root in "${roots[@]}"; do
    [ -e "$root" ] || continue
    find "$root" -name dosdevices -type d -print0 2>/dev/null |
      while IFS= read -r -d '' dir; do
        for link in "$dir"/*; do
          [ -e "$link" ] || [ -L "$link" ] || continue
          [ -L "$link" ] || continue

          name=$(basename "$link")
          target=$(readlink "$link")

          case "$name" in
            c:|lpt*|com*) continue ;;
          esac

          case "$target" in
            /dev/sr*|/dev/lp*|/dev/ttyS*) continue ;;
          esac

          case "$target" in
            /*) target_path=$target ;;
            *) target_path=$dir/$target ;;
          esac

          if [ ! -e "$target_path" ]; then
            echo "remove $link -> $target (broken)"
            if [ "$dry_run" != 1 ]; then
              rm -- "$link"
            fi
            continue
          fi

          is_allowed_target "$target_path" && continue

          echo "remove $link -> $target"
          if [ "$dry_run" != 1 ]; then
            rm -- "$link"
          fi
        done
      done || true
  done

  return 0
}

install_wrappers() {
  run install -d -m 755 "$bin_dir"

  write_file "$bin_dir/wine-strip-host-drives" <<'EOF'
#!/usr/bin/env bash
# Remove Wine/Proton dosdevices symlinks that expose the host filesystem or raw block devices.
set -euo pipefail

game_root="${WINE_GAME_ROOT:-/games}"

is_allowed() {
  local target=$1
  local resolved_game_root
  local resolved_target

  resolved_game_root=$(readlink -f "$game_root" 2>/dev/null || printf '%s\n' "$game_root")
  resolved_target=$(readlink -f "$target" 2>/dev/null || printf '%s\n' "$target")

  case "$resolved_target" in
    "$resolved_game_root"|"$resolved_game_root"/*) return 0 ;;
  esac

  return 1
}

roots=("$@")
[ "$#" -gt 0 ] || roots=("$HOME")

for root in "${roots[@]}"; do
  [ -e "$root" ] || continue
  find "$root" -name dosdevices -type d -print0 2>/dev/null |
    while IFS= read -r -d '' dir; do
      for link in "$dir"/*; do
        [ -e "$link" ] || [ -L "$link" ] || continue
        [ -L "$link" ] || continue

        name=$(basename "$link")
        target=$(readlink "$link")

        case "$name" in
          c:|lpt*|com*) continue ;;
        esac

        case "$target" in
          /dev/sr*|/dev/lp*|/dev/ttyS*) continue ;;
        esac

        case "$target" in
          /*) target_path=$target ;;
          *) target_path=$dir/$target ;;
        esac

        if [ ! -e "$target_path" ]; then
          echo "remove $link -> $target (broken)"
          if [ "${DRY_RUN:-0}" != 1 ]; then
            rm -- "$link"
          fi
          continue
        fi

        is_allowed "$target_path" && continue

        echo "remove $link -> $target"
        if [ "${DRY_RUN:-0}" != 1 ]; then
          rm -- "$link"
        fi
      done
    done || true
done

exit 0
EOF

  write_file "$bin_dir/wine-no-host-drives-wrapper" <<'EOF'
#!/usr/bin/env bash
# Run Wine through the system binary, but keep host filesystem drives out of prefixes.
set -u

cmd="${WINE_NO_HOST_DRIVES_CMD:-$(basename "$0")}"
real_dir="${WINE_NO_HOST_DRIVES_REAL_DIR:-/usr/sbin}"
real="$real_dir/$cmd"
prefix="${WINEPREFIX:-$HOME/.wine}"
stripper="$HOME/.local/bin/wine-strip-host-drives"

if [ ! -x "$real" ] && [ "$cmd" = "wine64" ]; then
  real="$real_dir/wine"
fi

if [ ! -x "$real" ]; then
  echo "missing real Wine command: $real" >&2
  exit 127
fi

strip_prefix() {
  [ -x "$stripper" ] || return 0
  [ -d "$prefix/dosdevices" ] || return 0
  "$stripper" "$prefix" >/dev/null || true
}

case "$cmd" in
  wine|wine64|winecfg)
    if [ ! -d "$prefix/dosdevices" ] && [ -x "$real_dir/wineboot" ]; then
      WINEPREFIX="$prefix" "$real_dir/wineboot" -u >/dev/null 2>&1 || true
    fi
    strip_prefix
    ;;
esac

"$real" "$@"
status=$?
strip_prefix
exit "$status"
EOF

  local cmd
  for cmd in wine wine64 wineboot winecfg wineserver; do
    write_file "$bin_dir/$cmd" <<EOF
#!/usr/bin/env bash
WINE_NO_HOST_DRIVES_CMD=$cmd exec "\$HOME/.local/bin/wine-no-host-drives-wrapper" "\$@"
EOF
  done
}

patch_proton_files() {
  command -v python3 >/dev/null || {
    echo "python3 is required to patch Proton launcher files" >&2
    return 1
  }

  local candidates=()
  local root
  for root in \
    "$target_home/.local/share/Steam/compatibilitytools.d" \
    "$target_home/.local/share/Steam/steamapps/common" \
    "$target_home/.local/share/umu/compatibilitytools" \
    "$target_home/.config/heroic/tools/proton"
  do
    [ -d "$root" ] || continue
    while IFS= read -r -d '' file; do
      candidates+=("$file")
    done < <(find "$root" -type f \( -name proton -o -name proton_3.7_tracked_files \) -print0 2>/dev/null)
  done

  [ "${#candidates[@]}" -gt 0 ] || return 0

  if [ "$dry_run" = 1 ]; then
    printf 'DRY_RUN: patch Proton files:\n'
    printf '  %s\n' "${candidates[@]}"
    return 0
  fi

  python3 - "${candidates[@]}" <<'PY'
from pathlib import Path
import sys

old = '''            if not file_exists(self.prefix_dir + "/dosdevices/z:", follow_symlinks=False):
                os.symlink("/", self.prefix_dir + "/dosdevices/z:")
'''
new = '''            # Do not expose the host root as Z: in newly created prefixes.
'''

strip_func = '''
def remove_host_dosdevices_for_launcher():
    """Remove Wine/Proton drive mappings that expose host filesystems."""
    stripper = os.path.expanduser("~/.local/bin/wine-strip-host-drives")
    if file_exists(stripper, follow_symlinks=True) and os.access(stripper, os.X_OK):
        subprocess.run(
            [stripper, g_compatdata.prefix_dir],
            stdout=subprocess.DEVNULL,
            stderr=subprocess.DEVNULL,
            check=False,
        )

'''

strip_func_anchor = "\ndef comma_escaped(s):\n"
launch_anchor = '''    #determine mode
    rc = 0
'''
launch_replacement = '''    remove_host_dosdevices_for_launcher()

    #determine mode
    rc = 0
'''
exit_anchor = '''    sys.exit(rc)
'''
exit_replacement = '''    remove_host_dosdevices_for_launcher()
    sys.exit(rc)
'''

for name in sys.argv[1:]:
    path = Path(name)
    try:
        text = path.read_text()
    except UnicodeDecodeError:
        continue

    updated = text
    if path.name == "proton":
        updated = updated.replace(old, new)
        if "def remove_host_dosdevices_for_launcher():" not in updated:
            updated = updated.replace(strip_func_anchor, "\n" + strip_func + "def comma_escaped(s):\n")
        if "    remove_host_dosdevices_for_launcher()\n\n    #determine mode" not in updated:
            updated = updated.replace(launch_anchor, launch_replacement)
        if "    remove_host_dosdevices_for_launcher()\n    sys.exit(rc)" not in updated:
            updated = updated.replace(exit_anchor, exit_replacement, 1)
    elif path.name == "proton_3.7_tracked_files":
        lines = [line for line in updated.splitlines() if line != "./dosdevices/z:"]
        updated = "\n".join(lines) + ("\n" if lines else "")

    if updated != text:
        path.write_text(updated)
        print(f"patched {path}")
PY
}

cleanup_prefixes() {
  strip_host_drives "$target_home" "$game_root"
}

main() {
  install_wrappers
  patch_proton_files
  cleanup_prefixes
}

main

bash <(curl -fsSL https://gist.githubusercontent.com/HackingGate/dc0da5c691e489080e71508814cae5e5/raw/disable-wine-host-drives.sh)