On 2021/8/6 下午7:42, Nikolay Borisov wrote:
On 6.08.21 г. 14:33, Qu Wenruo wrote:There is a kernel regression for btrfs, that when passing non-existing devid to "btrfs device remove" command, kernel will crash due to NULL pointer dereference. The test case is for such regression, it will: - Create and mount an empty single-device btrfs - Try to remove devid 3, which doesn't exist for above fs - Make sure the command exits properly with expected error message The kernel fix is titled "btrfs: fix NULL pointer dereference when deleting device by invalid id". Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> --- Changelog: v2: - Change the subject to also verify the error behavior - Include the error message into golden output - Also verify the return value of btrfs command --- tests/btrfs/244 | 47 +++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/244.out | 2 ++ 2 files changed, 49 insertions(+) create mode 100755 tests/btrfs/244 create mode 100644 tests/btrfs/244.out diff --git a/tests/btrfs/244 b/tests/btrfs/244 new file mode 100755 index 00000000..fbefeedf --- /dev/null +++ b/tests/btrfs/244 @@ -0,0 +1,47 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 SUSE Linux Products GmbH. All Rights Reserved. +# +# FS QA Test 244 +# +# Make sure "btrfs device remove" won't crash when non-existing devid +# is provided +# +. ./common/preamble +_begin_fstest auto quick volume dangerous + +# Override the default cleanup function. +# _cleanup() +# { +# cd / +# rm -r -f $tmp.* +# } + +# Import common functions. +# . ./common/filter + +# real QA test starts here + +# Modify as appropriate. +_supported_fs btrfs +_require_scratch + +_scratch_mkfs >> $seqres.full 2>&1 +_scratch_mount + +# Above created fs only contains one device with devid 1, device remove 3 +# should just fail with proper error message showing devid 3 can't be found. +# Although on unpatched kernel, this will trigger a NULL pointer dereference. +$BTRFS_UTIL_PROG device remove 3 $SCRATCH_MNT +ret=$? + +if [ $ret -ne 1 ]; then + echo "Unexpected return value from btrfs command, has $ret expected 1" +fi<rant> This just shows how broken progs are w.r.t return values. The generally accepted return value is 0 on success, yet it returns 1 on success since the functions implementing this functionality in progs treat the return value as a boolean. </rant>
Nope, we're testing a failure case, thus returning 1 is what we expect. Thanks, Qu
+ +# Fstests will automatically check the filesystem to make sure metadata is not +# corrupted. + +# success, all done +status=0 +exit diff --git a/tests/btrfs/244.out b/tests/btrfs/244.out new file mode 100644 index 00000000..629adf2a --- /dev/null +++ b/tests/btrfs/244.out @@ -0,0 +1,2 @@ +QA output created by 244 +ERROR: error removing devid 3: No such file or directory
