Exercise fs freeze/unfreeze and mount/umount race, which could lead to use-after-free oops. This commit fixed the issue: 1494583 fix get_active_super()/umount() race This test case is based on a script from Monakhov Dmitriy. Signed-off-by: Eryu Guan <eguan@xxxxxxxxxx> --- v3: - rebase and re-numbered to generic/085 - add more comments to explain why results of suspend/resume, mount/umount are ignored v2: - add comments to explain dmsetup is used not xfs_freeze to freeze filesystem - detect failures in setup phase, so test exits not continus with errors tests/generic/085 | 106 ++++++++++++++++++++++++++++++++++++++++++++++++++ tests/generic/085.out | 2 + tests/generic/group | 1 + 3 files changed, 109 insertions(+) create mode 100755 tests/generic/085 create mode 100644 tests/generic/085.out diff --git a/tests/generic/085 b/tests/generic/085 new file mode 100755 index 0000000..8398752 --- /dev/null +++ b/tests/generic/085 @@ -0,0 +1,106 @@ +#! /bin/bash +# FS QA Test No. 085 +# +# Exercise fs freeze/unfreeze and mount/umount race, which could lead to +# use-after-free oops. +# +# This commit fixed the issue: +# 1494583 fix get_active_super()/umount() race +# +#----------------------------------------------------------------------- +# Copyright (c) 2015 Red Hat Inc. 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() +{ + cd / + rm -f $tmp.* + cleanup_dmdev +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here +_supported_fs generic +_supported_os Linux +_require_scratch +_require_block_device $SCRATCH_DEV +_require_command $DMSETUP_PROG +_require_freeze + +setup_dmdev() +{ + table="0 $size_in_sector linear $SCRATCH_DEV 0" + $DMSETUP_PROG create $node --table "$table" >>$seqres.full 2>&1 && \ + $DMSETUP_PROG mknodes >/dev/null 2>&1 + return $? +} + +cleanup_dmdev() +{ + # in case it's still suspended and/or mounted + $DMSETUP_PROG resume $lvdev >/dev/null 2>&1 + $UMOUNT_PROG $lvdev >/dev/null 2>&1 + + $DMSETUP_PROG remove $node >>$seqres.full 2>&1 + $DMSETUP_PROG mknodes >/dev/null 2>&1 +} + +rm -f $seqres.full +echo "Silence is golden" + +size=$((256 * 1024 * 1024)) +size_in_sector=$((size / 512)) +_scratch_mkfs_sized $size >>$seqres.full 2>&1 + +node=$seq-test +lvdev=/dev/mapper/$node +setup_dmdev || _fail "setup dm device failed" + +# take use of dmsetup suspend to freeze the fs. +# xfs_freeze/fsfreeze cannot be used in this test, because it can possibly +# freeze the root fs of the host when SCRATCH_MNT is not mounted +# +# And the results of the racing commands (suspend/resume, mount/umount) are not +# important, as long as they're racing with each other. So just throw away the +# outputs and ignore the results. +for ((i=0; i<100; i++)); do + $DMSETUP_PROG suspend $lvdev >/dev/null 2>&1 + $DMSETUP_PROG resume $lvdev >/dev/null 2>&1 +done & +pid=$! +for ((i=0; i<100; i++)); do + $MOUNT_PROG $lvdev $SCRATCH_MNT >/dev/null 2>&1 + $UMOUNT_PROG $lvdev >/dev/null 2>&1 +done & +pid="$pid $!" + +wait $pid + +status=0 +exit diff --git a/tests/generic/085.out b/tests/generic/085.out new file mode 100644 index 0000000..76aef1a --- /dev/null +++ b/tests/generic/085.out @@ -0,0 +1,2 @@ +QA output created by 085 +Silence is golden diff --git a/tests/generic/group b/tests/generic/group index 5cbc1fe..a96b901 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -87,6 +87,7 @@ 082 auto quick 083 rw auto enospc stress 084 auto metadata quick +085 auto freeze mount 088 perms auto quick 089 metadata auto 091 rw auto quick -- 1.8.3.1 -- 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