On Fri, 16 Sept 2022 at 16:14, Petr Lautrbach <plautrba@xxxxxxxxxx> wrote:
>
> `fixfiles -M relabel` temporary bind mounts filestems before relabeling
> but it leaves a directory mounted in /tmp/tmp.XXXX when a user hits
> CTRL-C. It means that if the user run `fixfiles -M relabel` again and
> answered Y to clean out /tmp directory, it would remove all data from
> mounted fs.
>
> This patch changes the location where `fixfiles` mounts fs to /run and
> adds a handler for exit signals which tries to umount fs mounted by
> `fixfiles`.
What about additionally using mount namespaces, if available:
@@ -256,10 +256,16 @@
test -z ${TMP_MOUNT+x} && echo "Unable to find
temporary directory!" && exit 1
mkdir -p "${TMP_MOUNT}${m}" || exit 1
- mount --bind "${m}" "${TMP_MOUNT}${m}" || exit 1
- ${SETFILES} ${VERBOSE} ${EXCLUDEDIRS} ${FORCEFLAG}
${THREADS} $* -q ${FC} -r "${TMP_MOUNT}" "${TMP_MOUNT}${m}"
- umount "${TMP_MOUNT}${m}" || exit 1
- rm -rf "${TMP_MOUNT}" || echo "Error cleaning up."
+ if ! unshare --mount /bin/sh -c "mount --bind
\"${m}\" \"${TMP_MOUNT}${m}\" || exit 1 && ${SETFILES} ${VERBOSE}
${EXCLUDEDIRS} ${FORCEFLAG} ${THREADS} $* -q ${FC} -r \"${TMP_MOUNT}\"
\"${TMP_MOUNT}${m}\" || true"; then
+ echo "Creating new mount namespace failed,
operating in root namespace"
+ mount --bind "${m}" "${TMP_MOUNT}${m}" || exit 1
+ ${SETFILES} ${VERBOSE} ${EXCLUDEDIRS}
${FORCEFLAG} ${THREADS} $* -q ${FC} -r "${TMP_MOUNT}"
"${TMP_MOUNT}${m}"
+ umount "${TMP_MOUNT}${m}" || exit 1
+ fi
+ if [ "${m}" != '/' ]; then
+ rmdir "${TMP_MOUNT}${m}" || echo "Error
cleaning up ${TMP_MOUNT}${m}."
+ fi
+ rmdir "${TMP_MOUNT}" || echo "Error cleaning
up ${TMP_MOUNT}."
done;
fi
else
?
>
> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2125355
>
> Signed-off-by: Petr Lautrbach <plautrba@xxxxxxxxxx>
> ---
> v2:
>
> - set trap on EXIT instead of SIGINT
>
> v3:
>
> - use /run instead of /tmp for mountpoints
>
>
> policycoreutils/scripts/fixfiles | 13 ++++++++++++-
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/policycoreutils/scripts/fixfiles b/policycoreutils/scripts/fixfiles
> index c72ca0eb9d61..acf5f0996c19 100755
> --- a/policycoreutils/scripts/fixfiles
> +++ b/policycoreutils/scripts/fixfiles
> @@ -207,6 +207,15 @@ rpm -q --qf '[%{FILESTATES} %{FILENAMES}\n]' "$1" | grep '^0 ' | cut -f2- -d ' '
> [ ${PIPESTATUS[0]} != 0 ] && echo "$1 not found" >/dev/stderr
> }
>
> +# unmount tmp bind mount before exit
> +umount_TMP_MOUNT() {
> + if [ -n "$TMP_MOUNT" ]; then
> + umount "${TMP_MOUNT}${m}" || exit 130
> + rm -rf "${TMP_MOUNT}" || echo "Error cleaning up."
> + fi
> + exit 130
> +}
> +
> #
> # restore
> # if called with -n will only check file context
> @@ -251,8 +260,9 @@ case "$RESTORE_MODE" in
> else
> # we bind mount so we can fix the labels of files that have already been
> # mounted over
> + trap umount_TMP_MOUNT EXIT
> for m in `echo $FILESYSTEMSRW`; do
> - TMP_MOUNT="$(mktemp -d)"
> + TMP_MOUNT="$(mktemp -p /run -d fixfiles.XXXXXXXXXX)"
> test -z ${TMP_MOUNT+x} && echo "Unable to find temporary directory!" && exit 1
>
> mkdir -p "${TMP_MOUNT}${m}" || exit 1
> @@ -261,6 +271,7 @@ case "$RESTORE_MODE" in
> umount "${TMP_MOUNT}${m}" || exit 1
> rm -rf "${TMP_MOUNT}" || echo "Error cleaning up."
> done;
> + trap EXIT
> fi
> else
> echo >&2 "fixfiles: No suitable file systems found"
> --
> 2.37.3
>
