From: Filipe Manana <fdmanana@xxxxxxxx> Test that calling fsync against a file using the merged directory does not result in a crash nor fails unexpectedly. This is motivated by a change in overlayfs that resulted in a crash (invalid memory access) when the lower or upper directory belonged to a btrfs file system. The overlayfs change came in commit 4bacc9c9234 (overlayfs: Make f_path always point to the overlay and f_inode to the underlay). At the moment there are two patches in the linux-fsdevel and linux-btrfs mailing lists to fix this problem: * vfs: add file_dentry() * Btrfs: fix crash/invalid memory access on fsync when using overlayfs Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx> Reviewed-by: Eryu Guan <eguan@xxxxxxxxxx> --- V2: Removed leftover comment from debugging. V3: Change supperted fs type from generic to overlay. tests/overlay/002 | 74 +++++++++++++++++++++++++++++++++++++++++++++++++++ tests/overlay/002.out | 3 +++ tests/overlay/group | 1 + 3 files changed, 78 insertions(+) create mode 100755 tests/overlay/002 create mode 100644 tests/overlay/002.out diff --git a/tests/overlay/002 b/tests/overlay/002 new file mode 100755 index 0000000..ec7874e --- /dev/null +++ b/tests/overlay/002 @@ -0,0 +1,74 @@ +#! /bin/bash +# FS QA Test 002 +# +# Test that calling fsync against a file using the merged directory does not +# result in a crash nor fails unexpectedly. +# +# This is motivated by a change in overlayfs that resulted in a crash (invalid +# memory access) when the lower or upper directory belonged to a btrfs file +# system. +# +#----------------------------------------------------------------------- +# +# Copyright (C) 2016 SUSE Linux Products GmbH. All Rights Reserved. +# Author: Filipe Manana <fdmanana@xxxxxxxx> +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it would be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write the Free Software Foundation, +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +#----------------------------------------------------------------------- +# + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here +_supported_fs overlay +_supported_os Linux +_require_scratch + +# Remove all files from previous tests +_scratch_mkfs + +# Create our test file. +lowerdir=$SCRATCH_DEV/$OVERLAY_LOWER_DIR +mkdir -p $lowerdir +touch $lowerdir/foobar + +_scratch_mount + +# Write some data to our file and fsync it, using the merged directory path. +# This should work and not result in a crash. +$XFS_IO_PROG -c "pwrite 0 64k" -c "fsync" $SCRATCH_MNT/foobar | _filter_xfs_io + +# success, all done +status=0 +exit diff --git a/tests/overlay/002.out b/tests/overlay/002.out new file mode 100644 index 0000000..666e61e --- /dev/null +++ b/tests/overlay/002.out @@ -0,0 +1,3 @@ +QA output created by 002 +wrote 65536/65536 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) diff --git a/tests/overlay/group b/tests/overlay/group index 5056c3b..84d164e 100644 --- a/tests/overlay/group +++ b/tests/overlay/group @@ -4,3 +4,4 @@ # - comment line before each group is "new" description # 001 auto quick copyup +002 auto quick metadata -- 2.7.0.rc3 -- To unsubscribe from this list: send the line "unsubscribe fstests" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html