On Mon, Oct 23, 2023 at 07:32:59PM +0300, Amir Goldstein wrote:
> Check parsing and display of spaces and escaped colons and commans in
> lowerdir mount option.
>
> This is a regression test for two bugs introduced in v6.5 with the
> conversion to new mount api.
>
> There is another regression of new mount api related to libmount parsing
> of escaped commas, but this needs a fix in libmount - this test only
> verifies the fixes in the kernel, so it uses LIBMOUNT_FORCE_MOUNT2=always
> to force mount(2) and kernel pasring of the comma separated options list.
>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
>
> Changes since v2:
> - Fix test for when index feature is enabled
>
> Changes since v1:
> - Fix test for libmount >= 2.39
>
> tests/overlay/083 | 76 +++++++++++++++++++++++++++++++++++++++++++
> tests/overlay/083.out | 2 ++
> 2 files changed, 78 insertions(+)
> create mode 100755 tests/overlay/083
> create mode 100644 tests/overlay/083.out
>
> diff --git a/tests/overlay/083 b/tests/overlay/083
> new file mode 100755
> index 00000000..df82d1fd
> --- /dev/null
> +++ b/tests/overlay/083
> @@ -0,0 +1,76 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (C) 2023 CTERA Networks. All Rights Reserved.
> +#
> +# FS QA Test 083
> +#
> +# Test regressions in parsing and display of special chars in mount options.
> +#
> +# The following kernel commits from v6.5 introduced regressions:
> +# b36a5780cb44 ("ovl: modify layer parameter parsing")
> +# 1784fbc2ed9c ("ovl: port to new mount api")
> +#
> +
> +. ./common/preamble
> +_begin_fstest auto quick mount
> +
> +# Import common functions.
> +. ./common/filter
> +
> +# real QA test starts here
> +_supported_fs overlay
> +_fixed_by_kernel_commit 32db51070850 \
> + "ovl: fix regression in showing lowerdir mount option"
> +_fixed_by_kernel_commit c34706acf40b \
> + "ovl: fix regression in parsing of mount options with escaped comma"
> +
> +# _overlay_check_* helpers do not handle special chars well
> +_require_scratch_nocheck
> +
> +# Remove all files from previous tests
> +_scratch_mkfs
> +
> +# Create lowerdirs with special characters
> +lowerdir_spaces="$OVL_BASE_SCRATCH_MNT/lower1 with spaces"
> +lowerdir_colons="$OVL_BASE_SCRATCH_MNT/lower2:with::colons"
> +lowerdir_commas="$OVL_BASE_SCRATCH_MNT/lower3,with,,commas"
> +lowerdir_colons_esc="$OVL_BASE_SCRATCH_MNT/lower2\:with\:\:colons"
> +lowerdir_commas_esc="$OVL_BASE_SCRATCH_MNT/lower3\,with\,\,commas"
> +upperdir=$OVL_BASE_SCRATCH_MNT/$OVL_UPPER
> +workdir=$OVL_BASE_SCRATCH_MNT/$OVL_WORK
> +mkdir -p "$lowerdir_spaces" "$lowerdir_colons" "$lowerdir_commas"
> +
> +# _overlay_mount_* helpers do not handle special chars well, so execute mount directly.
> +# if escaped colons are not parsed correctly, mount will fail.
> +$MOUNT_PROG -t overlay ovl_esc_test $SCRATCH_MNT \
> + -o"upperdir=$upperdir,workdir=$workdir" \
> + -o"lowerdir=$lowerdir_colons_esc:$lowerdir_spaces" \
> + 2>&1 | tee -a $seqres.full
> +
> +# if spaces are not escaped when showing mount options,
> +# mount command will not show the word 'spaces' after the spaces
> +$MOUNT_PROG -t overlay | grep ovl_esc_test | tee -a $seqres.full | grep -v spaces && \
> + echo "ERROR: escaped spaces truncated from lowerdir mount option"
> +
> +# Re-create the upper/work dirs to mount them with a different lower
> +# This is required in case index feature is enabled
> +$UMOUNT_PROG $SCRATCH_MNT
> +rm -rf "$upperdir" "$workdir"
> +mkdir -p "$upperdir" "$workdir"
> +
> +# Kernel commit c34706acf40b fixes parsing of mount options with escaped comma
> +# when the mount options string is provided via data argument to mount(2) syscall.
> +# With libmount >= 2.39, libmount itself will try to split the comma separated
> +# options list provided to mount(8) commnad line and call fsconfig(2) for each
> +# mount option seperately. Since libmount does not obay to overlayfs escaped
> +# commas format, it will call fsconfig(2) with the wrong path (i.e. ".../lower3")
> +# and this test will fail, but the failure would indicate a libmount issue, not
> +# a kernel issue. Therefore, force libmount to use mount(2) syscall, so we only
> +# test the kernel fix.
> +LIBMOUNT_FORCE_MOUNT2=always $MOUNT_PROG -t overlay $OVL_BASE_SCRATCH_DEV $SCRATCH_MNT \
> + -o"upperdir=$upperdir,workdir=$workdir,lowerdir=$lowerdir_commas_esc" 2>> $seqres.full || \
> + echo "ERROR: incorrect parsing of escaped comma in lowerdir mount option"
This version looks good to me. I just hope we can remove the "LIBMOUNT_FORCE_MOUNT2=always"
after that issue get fixed, to let this case cover new mount API test too.
Reviewed-by: Zorro Lang <zlang@xxxxxxxxxx>
Thanks,
Zorro
> +
> +echo "Silence is golden"
> +status=0
> +exit
> diff --git a/tests/overlay/083.out b/tests/overlay/083.out
> new file mode 100644
> index 00000000..0beba309
> --- /dev/null
> +++ b/tests/overlay/083.out
> @@ -0,0 +1,2 @@
> +QA output created by 083
> +Silence is golden
> --
> 2.34.1
>
