[PATCH] ext4: Test for s_inodes_count overflow during fs resize

[Jan Kara <jack@suse.cz>]

Test for overflow of s_inodes_count during filesystem resizing.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 common/config      |   1 +
 common/rc          |   7 ++++
 tests/ext4/033     | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/ext4/033.out |   6 +++
 tests/ext4/group   |   1 +
 5 files changed, 133 insertions(+)
 create mode 100755 tests/ext4/033
 create mode 100644 tests/ext4/033.out

diff --git a/common/config b/common/config
index fa07a6799824..659ebeed3ffc 100644
--- a/common/config
+++ b/common/config
@@ -170,6 +170,7 @@ export INDENT_PROG="`set_prog_path indent`"
 export XFS_COPY_PROG="`set_prog_path xfs_copy`"
 export FSTRIM_PROG="`set_prog_path fstrim`"
 export DUMPE2FS_PROG="`set_prog_path dumpe2fs`"
+export RESIZE2FS_PROG="`set_prog_path resize2fs`"
 export FIO_PROG="`set_prog_path fio`"
 export FILEFRAG_PROG="`set_prog_path filefrag`"
 export E4DEFRAG_PROG="`set_prog_path e4defrag`"
diff --git a/common/rc b/common/rc
index 7368e2e12988..b8aad429e153 100644
--- a/common/rc
+++ b/common/rc
@@ -3176,6 +3176,13 @@ _require_dumpe2fs()
 	fi
 }
 
+_require_resize2fs()
+{
+	if [ -z "$RESIZE2FS_PROG" ]; then
+		_notrun "This test requires resize2fs utility."
+	fi
+}
+
 _require_ugid_map()
 {
 	if [ ! -e /proc/self/uid_map ]; then
diff --git a/tests/ext4/033 b/tests/ext4/033
new file mode 100755
index 000000000000..66760182e80f
--- /dev/null
+++ b/tests/ext4/033
@@ -0,0 +1,118 @@
+#! /bin/bash
+# FS QA Test 033
+#
+# Test s_inodes_count overflow for huge filesystems. This bug was fixed
+# by commit "ext4: Forbid overflowing inode count when resizing".
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2018 Jan Kara, SUSE.  All Rights Reserved.
+#
+# 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()
+{
+	_dmhugedisk_cleanup
+	# Recreate scratch so that _check_filesystems() does not complain
+	_scratch_mkfs >/dev/null 2>&1
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/dmhugedisk
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs ext4
+_supported_os Linux
+_require_scratch
+_require_dmhugedisk
+_require_dumpe2fs
+_require_resize2fs
+
+# Figure out block size
+echo "Figure out block size"
+_scratch_mkfs >/dev/null 2>&1
+_scratch_mount >> $seqres.full
+
+testdir=$SCRATCH_MNT/test-$seq
+blksz="$(_get_block_size $SCRATCH_MNT)"
+
+umount $SCRATCH_MNT
+
+INODES_PER_GROUP=$((blksz*8))
+GROUP_BLOCKS=$((blksz*8))
+
+# Number of groups to overflow s_inodes_count
+LIMIT_GROUPS=$(((1<<32)/INODES_PER_GROUP))
+
+# Create device huge enough so that overflowing inode count is possible
+echo "Format huge device"
+_dmhugedisk_init $(((LIMIT_GROUPS + 16)*GROUP_BLOCKS*(blksz/512)))
+
+# Start with small fs
+GROUP_COUNT=$((LIMIT_GROUPS-16))
+_mkfs_dev -N $((GROUP_COUNT*INODES_PER_GROUP)) -b $blksz \
+	$DMHUGEDISK_DEV $((GROUP_COUNT*GROUP_BLOCKS))
+
+_mount $DMHUGEDISK_DEV $SCRATCH_MNT
+
+echo "Initial fs dump" >> $seqres.full
+$DUMPE2FS_PROG -h $DMHUGEDISK_DEV >> $seqres.full 2>&1
+
+# This should fail, s_inodes_count would just overflow!
+echo "Resizing to inode limit + 1..."
+$RESIZE2FS_PROG $DMHUGEDISK_DEV $((LIMIT_GROUPS*GROUP_BLOCKS)) >> $seqres.full 2>&1
+if [ $? -eq 0 ]; then
+	echo "Resizing succeeded but it should fail!"
+	exit
+fi
+
+# This should succeed, we are maxing out inodes
+echo "Resizing to max group count..."
+$RESIZE2FS_PROG $DMHUGEDISK_DEV $(((LIMIT_GROUPS-1)*GROUP_BLOCKS)) >> $seqres.full 2>&1
+if [ $? -ne 0 ]; then
+	echo "Resizing failed!"
+	exit
+fi
+
+echo "Fs dump after resize" >> $seqres.full
+$DUMPE2FS_PROG -h $DMHUGEDISK_DEV >> $seqres.full 2>&1
+
+# This should fail, s_inodes_count would overflow by quite a bit!
+echo "Resizing device size..."
+$RESIZE2FS_PROG $DMHUGEDISK_DEV >> $seqres.full 2>&1
+if [ $? -eq 0 ]; then
+	echo "Resizing succeeded but it should fail!"
+	exit
+fi
+
+# success, all done
+status=0
+exit
diff --git a/tests/ext4/033.out b/tests/ext4/033.out
new file mode 100644
index 000000000000..3b7c748c6994
--- /dev/null
+++ b/tests/ext4/033.out
@@ -0,0 +1,6 @@
+QA output created by 033
+Figure out block size
+Format huge device
+Resizing to inode limit + 1...
+Resizing to max group count...
+Resizing device size...
diff --git a/tests/ext4/group b/tests/ext4/group
index 5bd15f82b3be..b850f568e674 100644
--- a/tests/ext4/group
+++ b/tests/ext4/group
@@ -35,6 +35,7 @@
 030 auto quick dax
 031 auto quick dax
 032 auto quick ioctl resize
+033 auto ioctl resize
 271 auto rw quick
 301 aio auto ioctl rw stress defrag
 302 aio auto ioctl rw stress defrag
-- 
2.13.6