V8.00.000.2025.06.17

Signed-off-by: Marc S. Weidner <msw@coresecret.dev>

func/system/4020_configure_system.sh

@@ -17,6 +17,8 @@ guard_sourcing
 # Globals:
 #   ERR_CHRT_MOUNTS
 #   TARGET
+#   VAR_CHROOT_ACTIVATED
+#   VAR_NEED_RUN_IN_TARGET
 # Arguments:
 #   None
 # Returns:
@@ -26,34 +28,93 @@ guard_sourcing
 configure_system() {
 
   ### Notes
+  # This file mounts all necessary pseudo filesystems into the target root environment to enable chroot operations.
   # --rbind: recursive binding.
   # --make-rslave: In this case, the mount point is marked as 'slave'.
-  # This means changes to the source mount (e.g., /proc) are propagated to the target mount (e.g., "${TARGET}"/proc).
+  # This means changes to the source mount (e.g., /proc) are propagated to the target mount (e.g., "${TARGET}/proc").
   # Conversely, changes to the target mount are not propagated back to the source mount.
   # This mode is necessary to avoid problems with double or erroneous propagation effects in chroot or container environments.
+  #
+  # Some subdirectories (such as /dev/pts, /dev/shm, /sys/fs/cgroup) are remounted with more restrictive options
+  # like 'noexec', 'nosuid', and 'nodev' to enhance security. This ensures they override the inherited bind-mounts and
+  # enforce proper runtime behavior in the chroot.
 
-  declare    var_src="" var_dst=""
-  declare -a ary_mounts=(proc sys dev run)
+  ### Declare Arrays, HashMaps, and Variables.
+  declare -A  HMP_SPECIAL_MOUNTS=(
+    ["/dev/pts"]="devpts devpts noexec,nosuid"                           ### Mount 'devpts' (used by pseudo-terminals).
+    ["/dev/shm"]="tmpfs tmpfs rw,nosuid,nodev"                           ### Mount 'tmpfs' for '/dev/shm' (shared memory).
+    ["/dev/mqueue"]="mqueue mqueue rw,nosuid,nodev,noexec"               ### Mount 'mqueue' for POSIX message queues.
+    ["/dev/hugepages"]="hugetlbfs hugetlbfs rw,nosuid,nodev"             ### Mount 'hugetlbfs' (huge pages, may be unused but required on some 'archs').
+    ["/sys/fs/cgroup"]="cgroup2 cgroup2 rw,nosuid,nodev,noexec,relatime" ### Mount unified 'cgroup2' hierarchy.
+  )
 
-  for var_src in "${ary_mounts[@]}"; do
-    var_dst="${TARGET}/${var_src}"
-    mkdir -p "${var_dst}"
+  declare -a  ary_mount=( "/proc" "/sys" "/dev" )
+  declare     var_src="" var_dst="" var_path="" var_fs="" var_opts=""
 
-    if ! mount --make-rslave --rbind "/${var_src}" "${var_dst}"; then
-      do_log "emergency" "file_only" "4020() Command: [mount --make-rslave --rbind /${var_src} ${var_dst}] failed."
+  for var_path in "${ary_mount[@]}" "${!HMP_SPECIAL_MOUNTS[@]}"; do
+
+    mkdir -p "${TARGET}${var_path}"
+
+  done
+
+  for var_src in "${ary_mount[@]}"; do
+    var_dst="${TARGET}${var_src}"
+
+    if ! mount --make-rslave --rbind "${var_src}" "${var_dst}"; then
+
+      do_log "emergency" "file_only" "4020() Command: [mount --make-rslave --rbind ${var_src} ${var_dst}] failed."
       return "${ERR_CHRT_MOUNTS}"
+
     fi
 
-    do_log "info" "file_only" "4020() Command: [mount --make-rslave --rbind /${var_src} ${var_dst}] successful."
+    do_log "info" "file_only" "4020() Command: [mount --make-rslave --rbind ${var_src} ${var_dst}] successful."
+
+  done
+
+  if [[ "${VAR_NEED_RUN_IN_TARGET:-false}" == "true" ]]; then
+
+    mkdir -p "${TARGET}/run"
+
+    if ! mount --make-rslave --rbind /run "${TARGET}/run"; then
+
+      do_log "emergency" "file_only" "4020() Command: [mount --make-rslave --rbind /run ${TARGET}/run] failed."
+      return "${ERR_CHRT_MOUNTS}"
+
+    fi
+
+    do_log "info" "file_only" "4020() Command: [mount --make-rslave --rbind /run ${TARGET}/run] successful."
+
+  fi
+
+  for var_path in "${!HMP_SPECIAL_MOUNTS[@]}"; do
+
+    IFS=" " read -r var_fs var_src var_opts <<< "${HMP_SPECIAL_MOUNTS[${var_path}]}"
+
+    if ! mount -t "${var_fs}" "${var_src}" "${TARGET}${var_path}" -o "${var_opts}"; then
+
+      do_log "emergency" "file_only" "4020() Command: [mount -t ${var_fs} ${var_src} ${TARGET}${var_path} -o ${var_opts}] failed."
+      return "${ERR_CHRT_MOUNTS}"
+
+    else
+
+      do_log "info" "file_only" "4020() Command: [mount -t ${var_fs} ${var_src} ${TARGET}${var_path} -o ${var_opts}] successful."
+
+    fi
 
   done
 
   if ! do_in_target "${TARGET}" mkdir -p /etc/systemd/system/multi-user.target.wants; then
+
+    do_log "emergency" "file_only" "4020() Command: [do_in_target ${TARGET} mkdir -p /etc/systemd/system/multi-user.target.wants] failed."
     return "${ERR_CHRT_MOUNTS}"
+
+  else
+
+    do_log "info" "file_only" "4020() Command: [do_in_target ${TARGET} mkdir -p /etc/systemd/system/multi-user.target.wants] successful."
+
   fi
 
-  do_log "info" "file_only" "4020() Command: [mkdir -p /etc/systemd/system/multi-user.target.wants] failed in: '${TARGET}'."
-
+  # shellcheck disable=SC2034
   declare -gx VAR_CHROOT_ACTIVATED="system"
 
   return 0