From: Petr Lautrbach <plautrba@redhat.com>
To: selinux@vger.kernel.org
Subject: Re: [PATCH v4] fixfiles: Unmount temporary bind mounts on SIGINT
Date: Fri, 04 Nov 2022 11:41:00 +0100 [thread overview]
Message-ID: <874jvfdmtf.fsf@redhat.com> (raw)
In-Reply-To: <20221007134600.137812-1-plautrba@redhat.com>
Petr Lautrbach <plautrba@redhat.com> writes:
> `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, uses
> private mount namespace via unshare and adds a handler for exit signals
> which tries to umount fs mounted by `fixfiles`.
>
> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2125355
>
> Signed-off-by: Petr Lautrbach <plautrba@redhat.com>
Is there anyone who objects?
Petr
> ---
> v2:
>
> - set trap on EXIT instead of SIGINT
>
> v3:
>
> - use /run instead of /tmp for mountpoints
>
> v4:
>
> - use mount namespace as suggested by Christian Göttsche <cgzones@googlemail.com> (September 16) (inbox)
>
>
> policycoreutils/scripts/fixfiles | 36 +++++++++++++++++++++++++-------
> 1 file changed, 28 insertions(+), 8 deletions(-)
>
> diff --git a/policycoreutils/scripts/fixfiles b/policycoreutils/scripts/fixfiles
> index c72ca0eb9d61..af64a5a567a6 100755
> --- a/policycoreutils/scripts/fixfiles
> +++ b/policycoreutils/scripts/fixfiles
> @@ -207,6 +207,25 @@ 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
> +}
> +
> +fix_labels_on_mountpoint() {
> + 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 "${TMP_MOUNT}" || echo "Error cleaning up."
> +}
> +export -f fix_labels_on_mountpoint
> +
> #
> # restore
> # if called with -n will only check file context
> @@ -252,14 +271,15 @@ case "$RESTORE_MODE" in
> # we bind mount so we can fix the labels of files that have already been
> # mounted over
> for m in `echo $FILESYSTEMSRW`; do
> - TMP_MOUNT="$(mktemp -d)"
> - 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 "${TMP_MOUNT}" || echo "Error cleaning up."
> + TMP_MOUNT="$(mktemp -p /run -d fixfiles.XXXXXXXXXX)"
> + export SETFILES VERBOSE EXCLUDEDIRS FORCEFLAG THREADS FC TMP_MOUNT m
> + if type unshare &> /dev/null; then
> + unshare -m bash -x -c "fix_labels_on_mountpoint" $* || exit $?
> + else
> + trap umount_TMP_MOUNT EXIT
> + fix_labels_on_mountpoint $*
> + trap EXIT
> + fi
> done;
> fi
> else
> --
> 2.37.3
next prev parent reply other threads:[~2022-11-04 10:42 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-15 12:44 [PATCH] fixfiles: Unmount temporary bind mounts on SIGINT Petr Lautrbach
2022-09-15 13:18 ` Ondrej Mosnacek
2022-09-15 16:29 ` Petr Lautrbach
2022-09-16 12:23 ` Ondrej Mosnacek
2022-09-16 13:45 ` Petr Lautrbach
2022-09-15 16:37 ` [PATCH v2] " Petr Lautrbach
2022-09-16 14:13 ` [PATCH v3] " Petr Lautrbach
2022-09-16 15:36 ` Christian Göttsche
2022-09-19 8:39 ` Ondrej Mosnacek
2022-09-19 11:17 ` Christian Göttsche
2022-10-07 13:46 ` [PATCH v4] " Petr Lautrbach
2022-11-04 10:41 ` Petr Lautrbach [this message]
2022-11-04 11:20 ` Christian Göttsche
2022-11-04 11:41 ` Petr Lautrbach
2022-11-05 9:24 ` Dominick Grift
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