If overlayfs xattr escaping is supported, ensure: * We can create "overlay.*" xattrs on a file in the overlayfs * We can create an xwhiteout file in the overlayfs We check for nesting support by trying to getattr an "overlay.*" xattr in an overlayfs mount, which will return ENOTSUPP in older kernels. Signed-off-by: Alexander Larsson <alexl@xxxxxxxxxx> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- Hi Zorro, This version fixes the failure with Kconfig CONFIG_OVERLAY_FS_INDEX=y. Thanks, Amir. tests/overlay/084 | 171 ++++++++++++++++++++++++++++++++++++++++++ tests/overlay/084.out | 61 +++++++++++++++ 2 files changed, 232 insertions(+) create mode 100755 tests/overlay/084 create mode 100644 tests/overlay/084.out diff --git a/tests/overlay/084 b/tests/overlay/084 new file mode 100755 index 00000000..8465caeb --- /dev/null +++ b/tests/overlay/084 @@ -0,0 +1,171 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2023 Red Hat, Inc. All Rights Reserved. +# Copyright (C) 2023 CTERA Networks. All Rights Reserved. +# +# FS QA Test No. 084 +# +# Test advanded nesting functionallity +# +. ./common/preamble +_begin_fstest auto quick nested + +# Override the default cleanup function. +_cleanup() +{ + cd / + # Unmount nested mounts if things fail + $UMOUNT_PROG $OVL_BASE_SCRATCH_MNT/nested 2>/dev/null + rm -rf $tmp +} + +# Import common functions. +. ./common/filter +. ./common/attr + +# real QA test starts here +_supported_fs overlay +# We use non-default scratch underlying overlay dirs, we need to check +# them explicity after test. +_require_scratch_nocheck +_require_scratch_overlay_xattr_escapes + +# remove all files from previous tests +_scratch_mkfs + +lowerdir=$OVL_BASE_SCRATCH_MNT/lower +middir=$OVL_BASE_SCRATCH_MNT/mid +upperdir=$OVL_BASE_SCRATCH_MNT/upper +workdir=$OVL_BASE_SCRATCH_MNT/workdir +nesteddir=$OVL_BASE_SCRATCH_MNT/nested + +umount_overlay() +{ + $UMOUNT_PROG $SCRATCH_MNT +} + +test_escape() +{ + local prefix=$1 + + echo -e "\n== Check xattr escape $prefix ==" + + # index feature would require nfs_export on $nesteddir mount + local extra_options="-o index=off" + if [ "$prefix" == "user" ]; then + extra_options+=",userxattr" + fi + + _scratch_mkfs + mkdir -p $lowerdir $middir $upperdir $workdir $nesteddir + + _overlay_scratch_mount_dirs $lowerdir $middir $workdir $extra_options + + mkdir -p $SCRATCH_MNT/layer1/dir/ $SCRATCH_MNT/layer2/dir + + touch $SCRATCH_MNT/layer1/dir/file + + # Make layer2/dir an opaque file + # Only one of these will be escaped, but both should succeed + setfattr -n user.overlay.opaque -v "y" $SCRATCH_MNT/layer2/dir + setfattr -n trusted.overlay.opaque -v "y" $SCRATCH_MNT/layer2/dir + + getfattr -m "overlay\\." --absolute-names -d $SCRATCH_MNT/layer2/dir | _filter_scratch + + umount_overlay + + getfattr -m "overlay\\." --absolute-names -d $middir/layer2/dir | _filter_scratch + + # Remount as lower and try again + _overlay_scratch_mount_dirs $middir:$lowerdir $upperdir $workdir $extra_options + + getfattr -m "overlay\\." --absolute-names -d $SCRATCH_MNT/layer2/dir | _filter_scratch + + # Recursively mount and ensure the opaque dir is working with both trusted and user xattrs + echo "nested xattr mount with trusted.overlay" + _overlay_mount_dirs $SCRATCH_MNT/layer2:$SCRATCH_MNT/layer1 - - overlayfs $nesteddir + stat $nesteddir/dir/file 2>&1 | _filter_scratch + $UMOUNT_PROG $nesteddir + + echo "nested xattr mount with user.overlay" + _overlay_mount_dirs $SCRATCH_MNT/layer2:$SCRATCH_MNT/layer1 - - -o userxattr overlayfs $nesteddir + stat $nesteddir/dir/file 2>&1 | _filter_scratch + $UMOUNT_PROG $nesteddir + + # Also ensure propagate the escaped xattr when we copy-up layer2/dir + echo "copy-up of escaped xattrs" + touch $SCRATCH_MNT/layer2/dir/other_file + getfattr -m "$prefix.overlay\\.overlay" --absolute-names -d $upperdir/layer2/dir | _filter_scratch + + umount_overlay +} + +test_escape trusted +test_escape user + +do_test_xwhiteout() +{ + local prefix=$1 + local basedir=$2 + + local extra_options="" + if [ "$prefix" == "user" ]; then + extra_options="-o userxattr" + fi + + mkdir -p $basedir/lower $basedir/upper $basedir/work + touch $basedir/lower/regular $basedir/lower/hidden $basedir/upper/hidden + setfattr -n $prefix.overlay.whiteouts -v "y" $basedir/upper + setfattr -n $prefix.overlay.whiteout -v "y" $basedir/upper/hidden + + # Test the hidden is invisible + _overlay_scratch_mount_dirs $basedir/upper:$basedir/lower - - $extra_options + ls $SCRATCH_MNT + stat $SCRATCH_MNT/hidden 2>&1 | _filter_scratch + umount_overlay +} + +# Validate that xwhiteouts work like whiteouts +test_xwhiteout() +{ + local prefix=$1 + + echo -e "\n== Check xwhiteout $prefix ==" + + _scratch_mkfs + + do_test_xwhiteout $prefix $OVL_BASE_SCRATCH_MNT +} + +test_xwhiteout trusted +test_xwhiteout user + +# Validate that (escaped) xwhiteouts work inside a nested overlayfs mount +test_escaped_xwhiteout() +{ + local prefix=$1 + + echo -e "\n== Check escaped xwhiteout $prefix ==" + + # index feature would require nfs_export on $nesteddir mount + local extra_options="-o index=off" + if [ "$prefix" == "user" ]; then + extra_options+=",userxattr" + fi + + _scratch_mkfs + mkdir -p $lowerdir $upperdir $workdir $nesteddir + + _overlay_mount_dirs $lowerdir $upperdir $workdir $extra_options overlayfs $nesteddir + + do_test_xwhiteout $prefix $nesteddir + + $UMOUNT_PROG $nesteddir +} + +test_escaped_xwhiteout trusted +test_escaped_xwhiteout user + +# success, all done +status=0 +exit diff --git a/tests/overlay/084.out b/tests/overlay/084.out new file mode 100644 index 00000000..54b890de --- /dev/null +++ b/tests/overlay/084.out @@ -0,0 +1,61 @@ +QA output created by 084 + +== Check xattr escape trusted == +# file: SCRATCH_MNT/layer2/dir +trusted.overlay.opaque="y" +user.overlay.opaque="y" + +# file: SCRATCH_DEV/mid/layer2/dir +trusted.overlay.overlay.opaque="y" +user.overlay.opaque="y" + +# file: SCRATCH_MNT/layer2/dir +trusted.overlay.opaque="y" +user.overlay.opaque="y" + +nested xattr mount with trusted.overlay +stat: cannot statx 'SCRATCH_DEV/nested/dir/file': No such file or directory +nested xattr mount with user.overlay +stat: cannot statx 'SCRATCH_DEV/nested/dir/file': No such file or directory +copy-up of escaped xattrs +# file: SCRATCH_DEV/upper/layer2/dir +trusted.overlay.overlay.opaque="y" + + +== Check xattr escape user == +# file: SCRATCH_MNT/layer2/dir +trusted.overlay.opaque="y" +user.overlay.opaque="y" + +# file: SCRATCH_DEV/mid/layer2/dir +trusted.overlay.opaque="y" +user.overlay.overlay.opaque="y" + +# file: SCRATCH_MNT/layer2/dir +trusted.overlay.opaque="y" +user.overlay.opaque="y" + +nested xattr mount with trusted.overlay +stat: cannot statx 'SCRATCH_DEV/nested/dir/file': No such file or directory +nested xattr mount with user.overlay +stat: cannot statx 'SCRATCH_DEV/nested/dir/file': No such file or directory +copy-up of escaped xattrs +# file: SCRATCH_DEV/upper/layer2/dir +user.overlay.overlay.opaque="y" + + +== Check xwhiteout trusted == +regular +stat: cannot statx 'SCRATCH_MNT/hidden': No such file or directory + +== Check xwhiteout user == +regular +stat: cannot statx 'SCRATCH_MNT/hidden': No such file or directory + +== Check escaped xwhiteout trusted == +regular +stat: cannot statx 'SCRATCH_MNT/hidden': No such file or directory + +== Check escaped xwhiteout user == +regular +stat: cannot statx 'SCRATCH_MNT/hidden': No such file or directory -- 2.34.1