#!/bin/bash KEXEC=/sbin/kexec KDUMP_KERNELVER="" KDUMP_KERNEL="" KDUMP_COMMANDLINE="" KEXEC_ARGS="" KDUMP_LOG_PATH="/var/log" MKDUMPRD="/sbin/mkdumprd -f" MKFADUMPRD="/sbin/mkfadumprd" DRACUT_MODULES_FILE="/usr/lib/dracut/modules.txt" SAVE_PATH=/var/crash SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa" INITRD_CHECKSUM_LOCATION="/boot/.fadump_initrd_checksum" DUMP_TARGET="" DEFAULT_INITRD="" DEFAULT_INITRD_BAK="" KDUMP_INITRD="" TARGET_INITRD="" FADUMP_REGISTER_SYS_NODE="/sys/kernel/fadump_registered" #kdump shall be the default dump mode DEFAULT_DUMP_MODE="kdump" image_time=0 standard_kexec_args="-d -p" # Some default values in case /etc/sysconfig/kdump doesn't include KDUMP_COMMANDLINE_REMOVE="hugepages hugepagesz slub_debug" if [[ -f /etc/sysconfig/kdump ]]; then . /etc/sysconfig/kdump fi [[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut . $dracutbasedir/dracut-functions.sh . /lib/kdump/kdump-lib.sh . /lib/kdump/kdump-logger.sh #initiate the kdump logger if ! dlog_init; then echo "failed to initiate the kdump logger." exit 1 fi single_instance_lock() { local rc timeout=5 if ! exec 9> /var/lock/kdump; then derror "Create file lock failed" exit 1 fi flock -n 9 rc=$? while [[ $rc -ne 0 ]]; do dinfo "Another app is currently holding the kdump lock; waiting for it to exit..." flock -w $timeout 9 rc=$? done } determine_dump_mode() { # Check if firmware-assisted dump is enabled # if yes, set the dump mode as fadump if is_fadump_capable; then dinfo "Dump mode is fadump" DEFAULT_DUMP_MODE="fadump" fi ddebug "DEFAULT_DUMP_MODE=$DEFAULT_DUMP_MODE" } save_core() { coredir="/var/crash/$(date +"%Y-%m-%d-%H:%M")" mkdir -p "$coredir" ddebug "cp --sparse=always /proc/vmcore $coredir/vmcore-incomplete" if cp --sparse=always /proc/vmcore "$coredir/vmcore-incomplete"; then mv "$coredir/vmcore-incomplete" "$coredir/vmcore" dinfo "saved a vmcore to $coredir" else derror "failed to save a vmcore to $coredir" fi # pass the dmesg to Abrt tool if exists, in order # to collect the kernel oops message. # https://fedorahosted.org/abrt/ if [[ -x /usr/bin/dumpoops ]]; then ddebug "makedumpfile --dump-dmesg $coredir/vmcore $coredir/dmesg" makedumpfile --dump-dmesg "$coredir/vmcore" "$coredir/dmesg" > /dev/null 2>&1 ddebug "dumpoops -d $coredir/dmesg" if dumpoops -d "$coredir/dmesg" > /dev/null 2>&1; then dinfo "kernel oops has been collected by abrt tool" fi fi } rebuild_fadump_initrd() { if ! $MKFADUMPRD "$DEFAULT_INITRD_BAK" "$TARGET_INITRD" --kver "$KDUMP_KERNELVER"; then derror "mkfadumprd: failed to make fadump initrd" return 1 fi return 0 } check_earlykdump_is_enabled() { grep -q -w "rd.earlykdump" /proc/cmdline return $? } rebuild_kdump_initrd() { ddebug "rebuild kdump initrd: $MKDUMPRD $TARGET_INITRD $KDUMP_KERNELVER" if ! $MKDUMPRD "$TARGET_INITRD" "$KDUMP_KERNELVER"; then derror "mkdumprd: failed to make kdump initrd" return 1 fi if check_earlykdump_is_enabled; then dwarn "Tips: If early kdump is enabled, also require rebuilding the system initramfs to make the changes take effect for early kdump." fi return 0 } rebuild_initrd() { if [[ ! -w $(dirname "$TARGET_INITRD") ]]; then derror "$(dirname "$TARGET_INITRD") does not have write permission. Cannot rebuild $TARGET_INITRD" return 1 fi if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then rebuild_fadump_initrd else rebuild_kdump_initrd fi return $? } #$1: the files to be checked with IFS=' ' check_exist() { for file in $1; do if [[ ! -e $file ]]; then derror "Error: $file not found." return 1 fi done } #$1: the files to be checked with IFS=' ' check_executable() { for file in $1; do if [[ ! -x $file ]]; then derror "Error: $file is not executable." return 1 fi done } backup_default_initrd() { ddebug "backup default initrd: $DEFAULT_INITRD" if [[ ! -f $DEFAULT_INITRD ]]; then return fi if [[ ! -e $DEFAULT_INITRD_BAK ]]; then dinfo "Backing up $DEFAULT_INITRD before rebuild." # save checksum to verify before restoring sha1sum "$DEFAULT_INITRD" > "$INITRD_CHECKSUM_LOCATION" if ! cp "$DEFAULT_INITRD" "$DEFAULT_INITRD_BAK"; then dwarn "WARNING: failed to backup $DEFAULT_INITRD." rm -f "$DEFAULT_INITRD_BAK" fi fi } restore_default_initrd() { ddebug "restore default initrd: $DEFAULT_INITRD" if [[ ! -f $DEFAULT_INITRD ]]; then return fi # If a backup initrd exists, we must be switching back from # fadump to kdump. Restore the original default initrd. if [[ -f $DEFAULT_INITRD_BAK ]] && [[ -f $INITRD_CHECKSUM_LOCATION ]]; then # verify checksum before restoring backup_checksum=$(sha1sum "$DEFAULT_INITRD_BAK" | awk '{ print $1 }') default_checksum=$(awk '{ print $1 }' "$INITRD_CHECKSUM_LOCATION") if [[ $default_checksum != "$backup_checksum" ]]; then dwarn "WARNING: checksum mismatch! Can't restore original initrd.." else rm -f $INITRD_CHECKSUM_LOCATION if mv "$DEFAULT_INITRD_BAK" "$DEFAULT_INITRD"; then derror "Restoring original initrd as fadump mode is disabled." sync fi fi fi } check_config() { local -A _opt_rec while read -r config_opt config_val; do case "$config_opt" in dracut_args) if [[ $config_val == *--mount* ]]; then if [[ $(echo "$config_val" | grep -o "\-\-mount" | wc -l) -ne 1 ]]; then derror 'Multiple mount targets specified in one "dracut_args".' return 1 fi config_opt=_target fi ;; raw) if [[ -d "/proc/device-tree/ibm,opal/dump" ]]; then dwarn "WARNING: Won't capture opalcore when 'raw' dump target is used." fi config_opt=_target ;; ext[234] | minix | btrfs | xfs | nfs | ssh) config_opt=_target ;; sshkey | path | core_collector | kdump_post | kdump_pre | extra_bins | extra_modules | failure_action | default | final_action | force_rebuild | force_no_rebuild | fence_kdump_args | fence_kdump_nodes) ;; net | options | link_delay | disk_timeout | debug_mem_level | blacklist) derror "Deprecated kdump config option: $config_opt. Refer to kdump.conf manpage for alternatives." return 1 ;; '') continue ;; *) derror "Invalid kdump config option $config_opt" return 1 ;; esac if [[ -z $config_val ]]; then derror "Invalid kdump config value for option '$config_opt'" return 1 fi if [[ -n ${_opt_rec[$config_opt]} ]]; then if [[ $config_opt == _target ]]; then derror "More than one dump targets specified" else derror "Duplicated kdump config value of option $config_opt" fi return 1 fi _opt_rec[$config_opt]="$config_val" done <<< "$(kdump_read_conf)" check_failure_action_config || return 1 check_final_action_config || return 1 check_fence_kdump_config || return 1 return 0 } # get_pcs_cluster_modified_files # return list of modified file for fence_kdump modified in Pacemaker cluster get_pcs_cluster_modified_files() { local time_stamp local modified_files is_generic_fence_kdump && return 1 is_pcs_fence_kdump || return 1 time_stamp=$(pcs cluster cib | xmllint --xpath 'string(/cib/@cib-last-written)' - | xargs -0 date +%s --date) if [[ -n $time_stamp ]] && [[ $time_stamp -gt $image_time ]]; then modified_files="cluster-cib" fi if [[ -f $FENCE_KDUMP_CONFIG_FILE ]]; then time_stamp=$(stat -c "%Y" "$FENCE_KDUMP_CONFIG_FILE") if [[ $time_stamp -gt $image_time ]]; then modified_files="$modified_files $FENCE_KDUMP_CONFIG_FILE" fi fi echo "$modified_files" } setup_initrd() { if ! prepare_kdump_bootinfo; then derror "failed to prepare for kdump bootinfo." return 1 fi DEFAULT_INITRD_BAK="$KDUMP_BOOTDIR/.$(basename "$DEFAULT_INITRD").default" if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then TARGET_INITRD="$DEFAULT_INITRD" # backup initrd for reference before replacing it # with fadump aware initrd backup_default_initrd else TARGET_INITRD="$KDUMP_INITRD" # check if a backup of default initrd exists. If yes, # it signifies a switch from fadump mode. So, restore # the backed up default initrd. restore_default_initrd fi } check_files_modified() { local modified_files="" #also rebuild when Pacemaker cluster conf is changed and fence kdump is enabled. modified_files=$(get_pcs_cluster_modified_files) EXTRA_BINS=$(kdump_get_conf_val kdump_post) CHECK_FILES=$(kdump_get_conf_val kdump_pre) HOOKS="/etc/kdump/post.d/ /etc/kdump/pre.d/" if [[ -d /etc/kdump/post.d ]]; then for file in /etc/kdump/post.d/*; do if [[ -x $file ]]; then POST_FILES="$POST_FILES $file" fi done fi if [[ -d /etc/kdump/pre.d ]]; then for file in /etc/kdump/pre.d/*; do if [[ -x $file ]]; then PRE_FILES="$PRE_FILES $file" fi done fi HOOKS="$HOOKS $POST_FILES $PRE_FILES" CORE_COLLECTOR=$(kdump_get_conf_val core_collector | awk '{print $1}') CORE_COLLECTOR=$(type -P "$CORE_COLLECTOR") # POST_FILES and PRE_FILES are already checked against executable, need not to check again. EXTRA_BINS="$EXTRA_BINS $CHECK_FILES" CHECK_FILES=$(kdump_get_conf_val extra_bins) EXTRA_BINS="$EXTRA_BINS $CHECK_FILES" files="$KDUMP_CONFIG_FILE $KDUMP_KERNEL $EXTRA_BINS $CORE_COLLECTOR" [[ -e /etc/fstab ]] && files="$files /etc/fstab" # Check for any updated extra module EXTRA_MODULES="$(kdump_get_conf_val extra_modules)" if [[ -n $EXTRA_MODULES ]]; then if [[ -e /lib/modules/$KDUMP_KERNELVER/modules.dep ]]; then files="$files /lib/modules/$KDUMP_KERNELVER/modules.dep" fi for _module in $EXTRA_MODULES; do if _module_file="$(modinfo --set-version "$KDUMP_KERNELVER" --filename "$_module" 2> /dev/null)"; then files="$files $_module_file" for _dep_modules in $(modinfo -F depends "$_module" | tr ',' ' '); do files="$files $(modinfo --set-version "$KDUMP_KERNELVER" --filename "$_dep_modules" 2> /dev/null)" done else # If it's not a module nor builtin, give an error if ! (modprobe --set-version "$KDUMP_KERNELVER" --dry-run "$_module" &> /dev/null); then dwarn "Module $_module not found" fi fi done fi # HOOKS is mandatory and need to check the modification time files="$files $HOOKS" check_exist "$files" && check_executable "$EXTRA_BINS" || return 2 for file in $files; do if [[ -e $file ]]; then time_stamp=$(stat -c "%Y" "$file") if [[ $time_stamp -gt $image_time ]]; then modified_files="$modified_files $file" fi if [[ -L $file ]]; then file=$(readlink -m "$file") time_stamp=$(stat -c "%Y" "$file") if [[ $time_stamp -gt $image_time ]]; then modified_files="$modified_files $file" fi fi else dwarn "$file doesn't exist" fi done if [[ -n $modified_files ]]; then dinfo "Detected change(s) in the following file(s): $modified_files" return 1 fi return 0 } check_drivers_modified() { local _target _new_drivers _old_drivers _module_name _module_filename # If it's dump target is on block device, detect the block driver _target=$(get_block_dump_target) if [[ -n $_target ]]; then _record_block_drivers() { local _drivers _drivers=$(udevadm info -a "/dev/block/$1" | sed -n 's/\s*DRIVERS=="\(\S\+\)"/\1/p') for _driver in $_drivers; do if ! [[ " $_new_drivers " == *" $_driver "* ]]; then _new_drivers="$_new_drivers $_driver" fi done ddebug "MAJ:MIN=$1 drivers='$_drivers'" } check_block_and_slaves_all _record_block_drivers "$(get_maj_min "$_target")" fi # Include watchdog drivers if watchdog module is not omitted is_dracut_mod_omitted watchdog || _new_drivers+=" $(get_watchdog_drvs)" [[ -z $_new_drivers ]] && return 0 if is_fadump_capable; then _old_drivers="$(lsinitrd "$TARGET_INITRD" -f /usr/lib/dracut/fadump-kernel-modules.txt | tr '\n' ' ')" else _old_drivers="$(lsinitrd "$TARGET_INITRD" -f /usr/lib/dracut/hostonly-kernel-modules.txt | tr '\n' ' ')" fi ddebug "Modules required for kdump: '$_new_drivers'" ddebug "Modules included in old initramfs: '$_old_drivers'" for _driver in $_new_drivers; do # Skip deprecated/invalid driver name or built-in module _module_name=$(modinfo --set-version "$KDUMP_KERNELVER" -F name "$_driver" 2> /dev/null) _module_filename=$(modinfo --set-version "$KDUMP_KERNELVER" -n "$_driver" 2> /dev/null) if [[ -z $_module_name ]] || [[ -z $_module_filename ]] || [[ $_module_filename == *"(builtin)"* ]]; then continue fi if ! [[ " $_old_drivers " == *" $_module_name "* ]]; then dinfo "Detected change in block device driver, new loaded module: $_module_name" return 1 fi done } check_fs_modified() { local _old_dev _old_mntpoint _old_fstype local _new_dev _new_mntpoint _new_fstype local _target _dracut_args # No need to check in case of mount target specified via "dracut_args". if is_mount_in_dracut_args; then return 0 fi # No need to check in case of raw target. # Currently we do not check also if ssh/nfs target is specified if is_ssh_dump_target || is_nfs_dump_target || is_raw_dump_target; then return 0 fi _target=$(get_block_dump_target) _new_fstype=$(get_fs_type_from_target "$_target") if [[ -z $_target ]] || [[ -z $_new_fstype ]]; then derror "Dump target is invalid" return 2 fi ddebug "_target=$_target _new_fstype=$_new_fstype" _new_dev=$(kdump_get_persistent_dev "$_target") if [[ -z $_new_dev ]]; then perror "Get persistent device name failed" return 2 fi _new_mntpoint="$(get_kdump_mntpoint_from_target "$_target")" _dracut_args=$(lsinitrd "$TARGET_INITRD" -f usr/lib/dracut/build-parameter.txt) if [[ -z $_dracut_args ]]; then dwarn "Warning: No dracut arguments found in initrd" return 0 fi # if --mount argument present then match old and new target, mount # point and file system. If any of them mismatches then rebuild if echo "$_dracut_args" | grep -q "\-\-mount"; then # shellcheck disable=SC2046 set -- $(echo "$_dracut_args" | awk -F "--mount '" '{print $2}' | cut -d' ' -f1,2,3) _old_dev=$1 _old_mntpoint=$2 _old_fstype=$3 [[ $_new_dev == "$_old_dev" && $_new_mntpoint == "$_old_mntpoint" && $_new_fstype == "$_old_fstype" ]] && return 0 # otherwise rebuild if target device is not a root device else [[ $_target == "$(get_root_fs_device)" ]] && return 0 fi dinfo "Detected change in File System" return 1 } # returns 0 if system is not modified # returns 1 if system is modified # returns 2 if system modification is invalid check_system_modified() { local ret [[ -f $TARGET_INITRD ]] || return 1 check_files_modified ret=$? if [[ $ret -ne 0 ]]; then return $ret fi check_fs_modified ret=$? if [[ $ret -ne 0 ]]; then return $ret fi check_drivers_modified ret=$? if [[ $ret -ne 0 ]]; then return $ret fi return 0 } check_rebuild() { local capture_capable_initrd="1" local force_rebuild force_no_rebuild local ret system_modified="0" setup_initrd || return 1 force_no_rebuild=$(kdump_get_conf_val force_no_rebuild) force_no_rebuild=${force_no_rebuild:-0} if [[ $force_no_rebuild != "0" ]] && [[ $force_no_rebuild != "1" ]]; then derror "Error: force_no_rebuild value is invalid" return 1 fi force_rebuild=$(kdump_get_conf_val force_rebuild) force_rebuild=${force_rebuild:-0} if [[ $force_rebuild != "0" ]] && [[ $force_rebuild != "1" ]]; then derror "Error: force_rebuild value is invalid" return 1 fi if [[ $force_no_rebuild == "1" && $force_rebuild == "1" ]]; then derror "Error: force_rebuild and force_no_rebuild are enabled simultaneously in kdump.conf" return 1 fi # Will not rebuild kdump initrd if [[ $force_no_rebuild == "1" ]]; then return 0 fi #check to see if dependent files has been modified #since last build of the image file if [[ -f $TARGET_INITRD ]]; then image_time=$(stat -c "%Y" "$TARGET_INITRD" 2> /dev/null) #in case of fadump mode, check whether the default/target #initrd is already built with dump capture capability if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then capture_capable_initrd=$(lsinitrd -f $DRACUT_MODULES_FILE "$TARGET_INITRD" | grep -c -e ^kdumpbase$ -e ^zz-fadumpinit$) fi fi check_system_modified ret=$? if [[ $ret -eq 2 ]]; then return 1 elif [[ $ret -eq 1 ]]; then system_modified="1" fi if [[ $image_time -eq 0 ]]; then dinfo "No kdump initial ramdisk found." elif [[ $capture_capable_initrd == "0" ]]; then dinfo "Rebuild $TARGET_INITRD with dump capture support" elif [[ $force_rebuild != "0" ]]; then dinfo "Force rebuild $TARGET_INITRD" elif [[ $system_modified != "0" ]]; then : else return 0 fi dinfo "Rebuilding $TARGET_INITRD" rebuild_initrd return $? } # On ppc64le LPARs, the keys trusted by firmware do not end up in # .builtin_trusted_keys. So instead, add the key to the .ima keyring function load_kdump_kernel_key() { # this is only called inside is_secure_boot_enforced, # no need to retest # this is only required if DT /ibm,secure-boot is a file. # if it is a dir, we are on OpenPower and don't need this. if ! [[ -f /proc/device-tree/ibm,secure-boot ]]; then return fi KDUMP_KEY_ID=$(keyctl padd asymmetric kernelkey-$RANDOM %:.ima < "/usr/share/doc/kernel-keys/$KDUMP_KERNELVER/kernel-signing-ppc.cer") } # remove a previously loaded key. There's no real security implication # to leaving it around, we choose to do this because it makes it easier # to be idempotent and so as to reduce the potential for confusion. function remove_kdump_kernel_key() { if [[ -z $KDUMP_KEY_ID ]]; then return fi keyctl unlink "$KDUMP_KEY_ID" %:.ima } # Load the kdump kernel specified in /etc/sysconfig/kdump # If none is specified, try to load a kdump kernel with the same version # as the currently running kernel. load_kdump() { local ret KEXEC_ARGS=$(prepare_kexec_args "${KEXEC_ARGS}") KDUMP_COMMANDLINE=$(prepare_cmdline "${KDUMP_COMMANDLINE}" "${KDUMP_COMMANDLINE_REMOVE}" "${KDUMP_COMMANDLINE_APPEND}") # For secureboot enabled machines, use new kexec file based syscall. # Old syscall will always fail as it does not have capability to # to kernel signature verification. if is_secure_boot_enforced; then dinfo "Secure Boot is enabled. Using kexec file based syscall." KEXEC_ARGS="$KEXEC_ARGS -s" load_kdump_kernel_key fi ddebug "$KEXEC $KEXEC_ARGS $standard_kexec_args --command-line=$KDUMP_COMMANDLINE --initrd=$TARGET_INITRD $KDUMP_KERNEL" # The '12' represents an intermediate temporary file descriptor # to store the standard error file descriptor '2', and later # restore the error file descriptor with the file descriptor '12' # and release it. exec 12>&2 exec 2>> $KDUMP_LOG_PATH/kdump.log PS4='+ $(date "+%Y-%m-%d %H:%M:%S") ${BASH_SOURCE}@${LINENO}: ' set -x # shellcheck disable=SC2086 $KEXEC $KEXEC_ARGS $standard_kexec_args \ --command-line="$KDUMP_COMMANDLINE" \ --initrd="$TARGET_INITRD" "$KDUMP_KERNEL" ret=$? set +x exec 2>&12 12>&- remove_kdump_kernel_key if [[ $ret == 0 ]]; then dinfo "kexec: loaded kdump kernel" return 0 else derror "kexec: failed to load kdump kernel" return 1 fi } check_ssh_config() { local SSH_TARGET while read -r config_opt config_val; do case "$config_opt" in sshkey) # remove inline comments after the end of a directive. if [[ -f $config_val ]]; then # canonicalize the path SSH_KEY_LOCATION=$(/usr/bin/readlink -m "$config_val") else dwarn "WARNING: '$config_val' doesn't exist, using default value '$SSH_KEY_LOCATION'" fi ;; path) SAVE_PATH=$config_val ;; ssh) DUMP_TARGET=$config_val ;; *) ;; esac done <<< "$(kdump_read_conf)" #make sure they've configured kdump.conf for ssh dumps SSH_TARGET=$(echo -n "$DUMP_TARGET" | sed -n '/.*@/p') if [[ -z $SSH_TARGET ]]; then return 1 fi return 0 } # ipv6 host address may takes a long time to be ready. # Instead of checking against ipv6 address, we just check the network reachable # by the return val of 'ssh' check_and_wait_network_ready() { local start_time local warn_once=1 local cur local diff local retval local errmsg start_time=$(date +%s) while true; do errmsg=$(ssh -i "$SSH_KEY_LOCATION" -o BatchMode=yes "$DUMP_TARGET" mkdir -p "$SAVE_PATH" 2>&1) retval=$? # ssh exits with the exit status of the remote command or with 255 if an error occurred if [[ $retval -eq 0 ]]; then return 0 elif [[ $retval -ne 255 ]]; then derror "Could not create $DUMP_TARGET:$SAVE_PATH, you should check the privilege on server side" return 1 fi # if server removes the authorized_keys or, no /root/.ssh/kdump_id_rsa ddebug "$errmsg" if echo "$errmsg" | grep -q "Permission denied\|No such file or directory\|Host key verification failed"; then derror "Could not create $DUMP_TARGET:$SAVE_PATH, you probably need to run \"kdumpctl propagate\"" return 1 fi if [[ $warn_once -eq 1 ]]; then dwarn "Network dump target is not usable, waiting for it to be ready..." warn_once=0 fi cur=$(date +%s) diff=$((cur - start_time)) # 60s time out if [[ $diff -gt 180 ]]; then break fi sleep 1 done dinfo "Could not create $DUMP_TARGET:$SAVE_PATH, ipaddr is not ready yet. You should check network connection" return 1 } check_ssh_target() { check_and_wait_network_ready } propagate_ssh_key() { if ! check_ssh_config; then derror "No ssh config specified in $KDUMP_CONFIG_FILE. Can't propagate" exit 1 fi local KEYFILE=$SSH_KEY_LOCATION local errmsg="Failed to propagate ssh key" #Check to see if we already created key, if not, create it. if [[ -f $KEYFILE ]]; then dinfo "Using existing keys..." else dinfo "Generating new ssh keys... " /usr/bin/ssh-keygen -t rsa -f "$KEYFILE" -N "" 2>&1 > /dev/null dinfo "done." fi #now find the target ssh user and server to contact. SSH_USER=$(echo "$DUMP_TARGET" | cut -d@ -f1) SSH_SERVER=$(echo "$DUMP_TARGET" | sed -e's/\(.*@\)\(.*$\)/\2/') #now send the found key to the found server ssh-copy-id -i "$KEYFILE" "$SSH_USER@$SSH_SERVER" RET=$? if [[ $RET == 0 ]]; then dinfo "$KEYFILE has been added to ~$SSH_USER/.ssh/authorized_keys on $SSH_SERVER" return 0 else derror "$errmsg, $KEYFILE failed in transfer to $SSH_SERVER" exit 1 fi } show_reserved_mem() { local mem local mem_mb mem=$(< /sys/kernel/kexec_crash_size) mem_mb=$((mem / 1024 / 1024)) dinfo "Reserved ${mem_mb}MB memory for crash kernel" } check_current_fadump_status() { # Check if firmware-assisted dump has been registered. rc=$(< $FADUMP_REGISTER_SYS_NODE) [[ $rc -eq 1 ]] && return 0 return 1 } check_current_status() { if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then check_current_fadump_status else check_current_kdump_status fi return $? } save_raw() { local kdump_dir local raw_target raw_target=$(kdump_get_conf_val raw) [[ -z $raw_target ]] && return 0 [[ -b $raw_target ]] || { derror "raw partition $raw_target not found" return 1 } check_fs=$(lsblk --nodeps -npo FSTYPE "$raw_target") if [[ $(echo "$check_fs" | wc -w) -ne 0 ]]; then dwarn "Warning: Detected '$check_fs' signature on $raw_target, data loss is expected." return 0 fi kdump_dir=$(kdump_get_conf_val path) if [[ -z ${kdump_dir} ]]; then coredir="/var/crash/$(date +"%Y-%m-%d-%H:%M")" else coredir="${kdump_dir}/$(date +"%Y-%m-%d-%H:%M")" fi mkdir -p "$coredir" [[ -d $coredir ]] || { derror "failed to create $coredir" return 1 } if makedumpfile -R "$coredir/vmcore" < "$raw_target" > /dev/null 2>&1; then # dump found dinfo "Dump saved to $coredir/vmcore" # wipe makedumpfile header dd if=/dev/zero of="$raw_target" bs=1b count=1 2> /dev/null else rm -rf "$coredir" fi return 0 } local_fs_dump_target() { local _target if _target=$(grep -E "^ext[234]|^xfs|^btrfs|^minix" /etc/kdump.conf); then echo "$_target" | awk '{print $2}' fi } path_to_be_relabeled() { local _path _target _mnt="/" _rmnt if is_user_configured_dump_target; then if is_mount_in_dracut_args; then return fi _target=$(local_fs_dump_target) if [[ -n $_target ]]; then _mnt=$(get_mntpoint_from_target "$_target") if ! is_mounted "$_mnt"; then return fi else return fi fi _path=$(get_save_path) # if $_path is masked by other mount, we will not relabel it. _rmnt=$(df "$_mnt/$_path" 2> /dev/null | tail -1 | awk '{ print $NF }') if [[ $_rmnt == "$_mnt" ]]; then echo "$_mnt/$_path" fi } selinux_relabel() { local _path _i _attr _path=$(path_to_be_relabeled) if [[ -z $_path ]] || ! [[ -d $_path ]]; then return fi while IFS= read -r -d '' _i; do _attr=$(getfattr -m "security.selinux" "$_i" 2> /dev/null) if [[ -z $_attr ]]; then restorecon "$_i" fi done < <(find "$_path" -print0) } check_fence_kdump_config() { local hostname local ipaddrs local nodes hostname=$(hostname) ipaddrs=$(hostname -I) nodes=$(kdump_get_conf_val "fence_kdump_nodes") for node in $nodes; do if [[ $node == "$hostname" ]]; then derror "Option fence_kdump_nodes cannot contain $hostname" return 1 fi # node can be ipaddr if echo "$ipaddrs " | grep -q "$node "; then derror "Option fence_kdump_nodes cannot contain $node" return 1 fi done return 0 } check_dump_feasibility() { if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then return 0 fi check_kdump_feasibility return $? } start_fadump() { echo 1 > $FADUMP_REGISTER_SYS_NODE if ! check_current_fadump_status; then derror "fadump: failed to register" return 1 fi dinfo "fadump: registered successfully" return 0 } start_dump() { if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then start_fadump else load_kdump fi return $? } check_failure_action_config() { local default_option local failure_action local option="failure_action" default_option=$(kdump_get_conf_val default) failure_action=$(kdump_get_conf_val failure_action) if [[ -z $failure_action ]] && [[ -z $default_option ]]; then return 0 elif [[ -n $failure_action ]] && [[ -n $default_option ]]; then derror "Cannot specify 'failure_action' and 'default' option together" return 1 fi if [[ -n $default_option ]]; then option="default" failure_action="$default_option" fi case "$failure_action" in reboot | halt | poweroff | shell | dump_to_rootfs) return 0 ;; *) dinfo $"Usage kdump.conf: $option {reboot|halt|poweroff|shell|dump_to_rootfs}" return 1 ;; esac } check_final_action_config() { local final_action final_action=$(kdump_get_conf_val final_action) if [[ -z $final_action ]]; then return 0 else case "$final_action" in reboot | halt | poweroff) return 0 ;; *) dinfo $"Usage kdump.conf: final_action {reboot|halt|poweroff}" return 1 ;; esac fi } start() { if ! check_dump_feasibility; then derror "Starting kdump: [FAILED]" return 1 fi if ! check_config; then derror "Starting kdump: [FAILED]" return 1 fi if sestatus 2> /dev/null | grep -q "SELinux status.*enabled"; then selinux_relabel fi if ! save_raw; then derror "Starting kdump: [FAILED]" return 1 fi if check_current_status; then dwarn "Kdump already running: [WARNING]" return 0 fi if check_ssh_config; then if ! check_ssh_target; then derror "Starting kdump: [FAILED]" return 1 fi fi if ! check_rebuild; then derror "Starting kdump: [FAILED]" return 1 fi if ! start_dump; then derror "Starting kdump: [FAILED]" return 1 fi dinfo "Starting kdump: [OK]" } reload() { if ! check_current_status; then dwarn "Kdump was not running: [WARNING]" fi if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then reload_fadump return $? else if ! stop_kdump; then derror "Stopping kdump: [FAILED]" return 1 fi fi dinfo "Stopping kdump: [OK]" if ! setup_initrd; then derror "Starting kdump: [FAILED]" return 1 fi if ! start_dump; then derror "Starting kdump: [FAILED]" return 1 fi dinfo "Starting kdump: [OK]" } stop_fadump() { echo 0 > $FADUMP_REGISTER_SYS_NODE if check_current_fadump_status; then derror "fadump: failed to unregister" return 1 fi dinfo "fadump: unregistered successfully" return 0 } stop_kdump() { if is_secure_boot_enforced; then $KEXEC -s -p -u else $KEXEC -p -u fi # shellcheck disable=SC2181 if [[ $? != 0 ]]; then derror "kexec: failed to unload kdump kernel" return 1 fi dinfo "kexec: unloaded kdump kernel" return 0 } reload_fadump() { if echo 1 > $FADUMP_REGISTER_SYS_NODE; then dinfo "fadump: re-registered successfully" return 0 else # FADump could fail on older kernel where re-register # support is not enabled. Try stop/start from userspace # to handle such scenario. if stop_fadump; then start_fadump return $? fi fi return 1 } stop() { if [[ $DEFAULT_DUMP_MODE == "fadump" ]]; then stop_fadump else stop_kdump fi # shellcheck disable=SC2181 if [[ $? != 0 ]]; then derror "Stopping kdump: [FAILED]" return 1 fi dinfo "Stopping kdump: [OK]" return 0 } rebuild() { check_config || return 1 if check_ssh_config; then if ! check_ssh_target; then return 1 fi fi setup_initrd || return 1 dinfo "Rebuilding $TARGET_INITRD" rebuild_initrd return $? } do_estimate() { local kdump_mods local -A large_mods local baseline local kernel_size mod_size initrd_size baseline_size runtime_size reserved_size estimated_size recommended_size local size_mb=$((1024 * 1024)) setup_initrd if [[ ! -f $TARGET_INITRD ]]; then derror "kdumpctl estimate: kdump initramfs is not built yet." exit 1 fi kdump_mods="$(lsinitrd "$TARGET_INITRD" -f /usr/lib/dracut/hostonly-kernel-modules.txt | tr '\n' ' ')" baseline=$(kdump_get_arch_recommend_size) if [[ ${baseline: -1} == "M" ]]; then baseline=${baseline%M} elif [[ ${baseline: -1} == "G" ]]; then baseline=$((${baseline%G} * 1024)) elif [[ ${baseline: -1} == "T" ]]; then baseline=$((${baseline%Y} * 1048576)) fi # The default pre-reserved crashkernel value baseline_size=$((baseline * size_mb)) # Current reserved crashkernel size reserved_size=$(< /sys/kernel/kexec_crash_size) # A pre-estimated value for userspace usage and kernel # runtime allocation, 64M should good for most cases runtime_size=$((64 * size_mb)) # Kernel image size kernel_size=$(get_kernel_size "$KDUMP_KERNEL") # Kdump initramfs size initrd_size=$(du -b "$TARGET_INITRD" | awk '{print $1}') # Kernel modules static size after loaded mod_size=0 while read -r _name _size _; do if [[ " $kdump_mods " != *" $_name "* ]]; then continue fi mod_size=$((mod_size + _size)) # Mark module with static size larger than 2M as large module if [[ $((_size / size_mb)) -ge 1 ]]; then large_mods[$_name]=$_size fi done <<< "$(< /proc/modules)" # Extra memory usage required for LUKS2 decryption crypt_size=0 for _dev in $(get_all_kdump_crypt_dev); do _crypt_info=$(cryptsetup luksDump "/dev/block/$_dev") [[ $(echo "$_crypt_info" | sed -n "s/^Version:\s*\(.*\)/\1/p") == "2" ]] || continue for _mem in $(echo "$_crypt_info" | sed -n "s/\sMemory:\s*\(.*\)/\1/p" | sort -n); do crypt_size=$((crypt_size + _mem * 1024)) break done done [[ $crypt_size -ne 0 ]] && echo -e "Encrypted kdump target requires extra memory, assuming using the keyslot with minimun memory requirement\n" estimated_size=$((kernel_size + mod_size + initrd_size + runtime_size + crypt_size)) if [[ $baseline_size -gt $estimated_size ]]; then recommended_size=$baseline_size else recommended_size=$estimated_size fi echo "Reserved crashkernel: $((reserved_size / size_mb))M" echo "Recommended crashkernel: $((recommended_size / size_mb))M" echo echo "Kernel image size: $((kernel_size / size_mb))M" echo "Kernel modules size: $((mod_size / size_mb))M" echo "Initramfs size: $((initrd_size / size_mb))M" echo "Runtime reservation: $((runtime_size / size_mb))M" [[ $crypt_size -ne 0 ]] && echo "LUKS required size: $((crypt_size / size_mb))M" echo -n "Large modules:" if [[ ${#large_mods[@]} -eq 0 ]]; then echo " " else echo "" for _mod in "${!large_mods[@]}"; do echo " $_mod: ${large_mods[$_mod]}" done fi if [[ $reserved_size -lt $recommended_size ]]; then echo "WARNING: Current crashkernel size is lower than recommended size $((recommended_size / size_mb))M." fi } get_default_crashkernel() { local _dump_mode=$1 kdump_get_arch_recommend_crashkernel "$_dump_mode" } # Read kernel cmdline parameter for a specific kernel # $1: kernel path, DEFAULT or kernel path, ALL not accepted # $2: kernel cmldine parameter get_grub_kernel_boot_parameter() { local _kernel_path=$1 _para=$2 [[ $_kernel_path == ALL ]] && derror "kernel_path=ALL invalid for get_grub_kernel_boot_parameter" && return 1 grubby --info="$_kernel_path" | sed -En -e "/^args=.*$/{s/^.*(\s|\")${_para}=(\S*).*\"$/\2/p;q}" } # get dump mode by fadump value # return # - fadump, if fadump=on or fadump=nocma # - kdump, if fadump=off or empty fadump, return kdump # - error if otherwise get_dump_mode_by_fadump_val() { local _fadump_val=$1 if [[ -z $_fadump_val ]] || [[ $_fadump_val == off ]]; then echo -n kdump elif [[ $_fadump_val == on ]] || [[ $_fadump_val == nocma ]]; then echo -n fadump else derror "invalid fadump=$_fadump_val" return 1 fi } # get dump mode of a specific kernel # based on its fadump kernel cmdline parameter get_dump_mode_by_kernel() { local _kernel_path=$1 _fadump_val _dump_mode _fadump_val=$(get_grub_kernel_boot_parameter "$_kernel_path" fadump) if _dump_mode=$(get_dump_mode_by_fadump_val "$_fadump_val"); then echo -n "$_dump_mode" else derror "failed to get dump mode for kernel $_kernel_path" exit fi } _filter_grubby_kernel_str() { local _grubby_kernel_str=$1 echo -n "$_grubby_kernel_str" | sed -n -e 's/^kernel="\(.*\)"/\1/p' } _find_kernel_path_by_release() { local _release="$1" _grubby_kernel_str _kernel_path _grubby_kernel_str=$(grubby --info ALL | grep "^kernel=.*$_release") _kernel_path=$(_filter_grubby_kernel_str "$_grubby_kernel_str") if [[ -z $_kernel_path ]]; then derror "kernel $_release doesn't exist" return 1 fi echo -n "$_kernel_path" } _get_current_running_kernel_path() { local _release _path _release=$(uname -r) if _path=$(_find_kernel_path_by_release "$_release"); then echo -n "$_path" else return 1 fi } _update_grub() { local _kernel_path=$1 _crashkernel=$2 _dump_mode=$3 _fadump_val=$4 if is_atomic; then if rpm-ostree kargs | grep -q "crashkernel="; then rpm-ostree kargs --replace="crashkernel=$_crashkernel" else rpm-ostree kargs --append="crashkernel=$_crashkernel" fi else [[ -f /etc/zipl.conf ]] && zipl_arg="--zipl" grubby --args "crashkernel=$_crashkernel" --update-kernel "$_kernel_path" $zipl_arg if [[ $_dump_mode == kdump ]]; then grubby --remove-args="fadump" --update-kernel "$_kernel_path" else grubby --args="fadump=$_fadump_val" --update-kernel "$_kernel_path" fi fi [[ $zipl_arg ]] && zipl > /dev/null } _valid_grubby_kernel_path() { [[ -n "$1" ]] && grubby --info="$1" > /dev/null 2>&1 } _get_all_kernels_from_grubby() { local _kernels _line _kernel_path _grubby_kernel_path=$1 for _line in $(grubby --info "$_grubby_kernel_path" | grep "^kernel="); do _kernel_path=$(_filter_grubby_kernel_str "$_line") _kernels="$_kernels $_kernel_path" done echo -n "$_kernels" } GRUB_ETC_DEFAULT="/etc/default/grub" # modify the kernel command line parameter in default grub conf # # $1: the name of the kernel command line parameter # $2: new value. If empty, the parameter would be removed _update_kernel_cmdline_in_grub_etc_default() { local _para=$1 _val=$2 _para_val _regex if [[ -n $_val ]]; then _para_val="$_para=$_val" fi _regex='^(GRUB_CMDLINE_LINUX=.*)([[:space:]"])'"$_para"'=[^[:space:]"]*(.*)$' if grep -q -E "$_regex" "$GRUB_ETC_DEFAULT"; then sed -i -E 's/'"$_regex"'/\1\2'"$_para_val"'\3/' "$GRUB_ETC_DEFAULT" elif [[ -n $_para_val ]]; then # If the kernel parameter doesn't exist, put it in the first sed -i -E 's/^(GRUB_CMDLINE_LINUX=")/\1'"$_para_val"' /' "$GRUB_ETC_DEFAULT" fi } reset_crashkernel() { local _opt _val _dump_mode _fadump_val _reboot _grubby_kernel_path _kernel _kernels local _old_crashkernel _new_crashkernel _new_dump_mode _crashkernel_changed local _new_fadump_val _old_fadump_val _what_is_updated for _opt in "$@"; do case "$_opt" in --fadump=*) _val=${_opt#*=} if _dump_mode=$(get_dump_mode_by_fadump_val $_val); then _fadump_val=$_val else derror "failed to determine dump mode" exit fi ;; --kernel=*) _val=${_opt#*=} if ! _valid_grubby_kernel_path $_val; then derror "Invalid $_opt, please specify a valid kernel path, ALL or DEFAULT" exit fi _grubby_kernel_path=$_val ;; --reboot) _reboot=yes ;; *) derror "$_opt not recognized" exit 1 ;; esac done # 1. CoreOS uses "rpm-ostree kargs" instead of grubby to manage kernel command # line. --kernel=ALL doesn't make sense for CoreOS. # 2. CoreOS doesn't support POWER so the dump mode is always kdump. # 3. "rpm-ostree kargs" would prompt the user to reboot the system after # modifying the kernel command line so there is no need for kexec-tools # to repeat it. if is_atomic; then _old_crashkernel=$(rpm-ostree kargs | sed -n -E 's/.*(^|\s)crashkernel=(\S*).*/\2/p') _new_dump_mode=kdump _new_crashkernel=$(kdump_get_arch_recommend_crashkernel "$_new_dump_mode") if [[ $_old_crashkernel != "$_new_crashkernel" ]]; then _update_grub "" "$_new_crashkernel" "$_new_dump_mode" "" if [[ $_reboot == yes ]]; then systemctl reboot fi fi return fi # For non-ppc64le systems, the dump mode is always kdump since only ppc64le # has FADump. if [[ -z $_dump_mode && $(uname -m) != ppc64le ]]; then _dump_mode=kdump _fadump_val=off fi # If the dump mode is determined, we can also know the default crashkernel value if [[ -n $_dump_mode ]]; then _crashkernel=$(kdump_get_arch_recommend_crashkernel "$_dump_mode") fi # If --kernel-path=ALL, update GRUB_CMDLINE_LINUX in /etc/default/grub. # # An exception case is when the ppc64le user doesn't specify the fadump value. # In this case, the dump mode would be determined by parsing the kernel # command line of the kernel(s) to be updated thus don't update GRUB_CMDLINE_LINUX. # # The following code has been simplified because of what has been done early, # - set the dump mode as kdump for non-ppc64le cases # - retrieved the default crashkernel value for given dump mode if [[ $_grubby_kernel_path == ALL && -n $_dump_mode ]]; then _update_kernel_cmdline_in_grub_etc_default crashkernel "$_crashkernel" # remove the fadump if fadump is disabled [[ $_fadump_val == off ]] && _fadump_val="" _update_kernel_cmdline_in_grub_etc_default fadump "$_fadump_val" fi # If kernel-path not specified, either # - use KDUMP_KERNELVER if it's defined # - use current running kernel if [[ -z $_grubby_kernel_path ]]; then if [[ -z $KDUMP_KERNELVER ]] || ! _kernel_path=$(_find_kernel_path_by_release "$KDUMP_KERNELVER"); then if ! _kernel_path=$(_get_current_running_kernel_path); then derror "no running kernel found" exit 1 fi fi _kernels=$_kernel_path else _kernels=$(_get_all_kernels_from_grubby "$_grubby_kernel_path") fi for _kernel in $_kernels; do if [[ -z $_dump_mode ]]; then _new_dump_mode=$(get_dump_mode_by_kernel "$_kernel") _new_crashkernel=$(kdump_get_arch_recommend_crashkernel "$_new_dump_mode") _new_fadump_val=$(get_grub_kernel_boot_parameter "$_kernel" fadump) else _new_dump_mode=$_dump_mode _new_crashkernel=$_crashkernel _new_fadump_val=$_fadump_val fi _old_crashkernel=$(get_grub_kernel_boot_parameter "$_kernel" crashkernel) _old_fadump_val=$(get_grub_kernel_boot_parameter "$_kernel" fadump) if [[ $_old_crashkernel != "$_new_crashkernel" || $_old_fadump_val != "$_new_fadump_val" ]]; then _update_grub "$_kernel" "$_new_crashkernel" "$_new_dump_mode" "$_new_fadump_val" if [[ $_reboot != yes ]]; then if [[ $_old_crashkernel != "$_new_crashkernel" ]]; then _what_is_updated="Updated crashkernel=$_new_crashkernel" else # This case happens only when switching between fadump=on and fadump=nocma _what_is_updated="Updated fadump=$_new_fadump_val" fi dwarn "$_what_is_updated for kernel=$_kernel. Please reboot the system for the change to take effect." fi _crashkernel_changed=yes fi done if [[ $_reboot == yes && $_crashkernel_changed == yes ]]; then reboot fi } # shellcheck disable=SC2154 # false positive when dereferencing an array reset_crashkernel_after_update() { local _kernel _crashkernel _dump_mode _fadump_val _old_default_crashkernel _new_default_crashkernel declare -A _crashkernel_vals _crashkernel_vals[old_kdump]=$(cat /tmp/old_default_crashkernel 2> /dev/null) _crashkernel_vals[old_fadump]=$(cat /tmp/old_default_crashkernel_fadump 2> /dev/null) _crashkernel_vals[new_kdump]=$(get_default_crashkernel kdump) _crashkernel_vals[new_fadump]=$(get_default_crashkernel fadump) for _kernel in $(_get_all_kernels_from_grubby); do _crashkernel=$(get_grub_kernel_boot_parameter "$_kernel" crashkernel) if [[ $_crashkernel == auto ]]; then reset_crashkernel "--kernel=$_kernel" elif [[ -n $_crashkernel ]]; then _dump_mode=$(get_dump_mode_by_kernel "$_kernel") _old_default_crashkernel=${_crashkernel_vals[old_${_dump_mode}]} _new_default_crashkernel=${_crashkernel_vals[new_${_dump_mode}]} if [[ $_crashkernel == "$_old_default_crashkernel" ]] && [[ $_new_default_crashkernel != "$_old_default_crashkernel" ]]; then _fadump_val=$(get_grub_kernel_boot_parameter "$_kernel" fadump) if _update_grub "$_kernel" "$_new_default_crashkernel" "$_dump_mode" "$_fadump_val"; then echo "For kernel=$_kernel, crashkernel=$_new_default_crashkernel now." fi fi fi done } reset_crashkernel_for_installed_kernel() { local _installed_kernel _running_kernel _crashkernel _crashkernel_running local _dump_mode_running _fadump_val_running if ! _installed_kernel=$(_find_kernel_path_by_release "$1"); then exit 1 fi if ! _running_kernel=$(_get_current_running_kernel_path); then derror "Couldn't find current running kernel" exit fi _crashkernel=$(get_grub_kernel_boot_parameter "$_installed_kernel" crashkernel) _crashkernel_running=$(get_grub_kernel_boot_parameter "$_running_kernel" crashkernel) _dump_mode_running=$(get_dump_mode_by_kernel "$_running_kernel") _fadump_val_running=$(get_grub_kernel_boot_parameter "$_kernel" fadump) if [[ $_crashkernel != "$_crashkernel_running" ]]; then if _update_grub "$_installed_kernel" "$_crashkernel_running" "$_dump_mode_running" "$_fadump_val_running"; then echo "kexec-tools has reset $_installed_kernel to use the new default crashkernel value $_crashkernel_running" fi fi } if [[ ! -f $KDUMP_CONFIG_FILE ]]; then derror "Error: No kdump config file found!" exit 1 fi main() { # Determine if the dump mode is kdump or fadump determine_dump_mode case "$1" in start) if [[ -s /proc/vmcore ]]; then save_core reboot else start fi ;; stop) stop ;; status) EXIT_CODE=0 check_current_status case "$?" in 0) dinfo "Kdump is operational" EXIT_CODE=0 ;; 1) dinfo "Kdump is not operational" EXIT_CODE=3 ;; esac exit $EXIT_CODE ;; reload) reload ;; restart) stop start ;; rebuild) rebuild ;; condrestart) ;; propagate) propagate_ssh_key ;; showmem) show_reserved_mem ;; estimate) do_estimate ;; get-default-crashkernel) get_default_crashkernel "$2" ;; reset-crashkernel) shift reset_crashkernel "$@" ;; reset-crashkernel-after-update) if [[ $(kdump_get_conf_val auto_reset_crashkernel) != no ]]; then reset_crashkernel_after_update fi ;; reset-crashkernel-for-installed_kernel) if [[ $(kdump_get_conf_val auto_reset_crashkernel) != no ]]; then reset_crashkernel_for_installed_kernel "$2" fi ;; *) dinfo $"Usage: $0 {estimate|start|stop|status|restart|reload|rebuild|reset-crashkernel|propagate|showmem}" exit 1 ;; esac } # Other kdumpctl instances will block in queue, until this one exits single_instance_lock # To avoid fd 9 leaking, we invoke a subshell, close fd 9 and call main. # So that fd isn't leaking when main is invoking a subshell. ( exec 9<&- main "$@" ) exit $?