Re: [PATCH v2] ext4/309: add test for ext4_dir_entry2 wipe

xuyang2018.jy
2021-06-03T05:37:36Z

on 2021/5/17 22:48, Leah Rumancik wrote:
> From: Leah Rumancik<lrumancik@google.com>
>
> Check wiping of dir entry data upon removing a file, converting to an
> htree, and splitting htree nodes.
>
> Tests commit 6c0912739699d8e4b6a87086401bf3ad3c59502d ("ext4: wipe
> ext4_dir_entry2 upon file deletion").
>
> Signed-off-by: Leah Rumancik<leah.rumancik@gmail.com>
>
> Changes in v2:
> - fix formatting
> - use _get_block_size instead of manually finding blocksize
> - change scratch_dir to testdir to avoid confusion
> ---
> tests/ext4/309 | 191 +++++++++++++++++++++++++++++++++++++++++++++
> tests/ext4/309.out | 5 ++
> tests/ext4/group | 1 +
> 3 files changed, 197 insertions(+)
> create mode 100755 tests/ext4/309
> create mode 100644 tests/ext4/309.out
>
> diff --git a/tests/ext4/309 b/tests/ext4/309
> new file mode 100755
> index 00000000..a4f74e7f
> --- /dev/null
> +++ b/tests/ext4/309
> @@ -0,0 +1,191 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2021 Google, Inc. All Rights Reserved.
> +#
> +# FS QA Test No. 309
> +#
> +# Test wiping of ext4_dir_entry2 data upon file removal, conversion
> +# to htree, and splitting of htree nodes
> +#
> +seq=`basename $0`
> +seqres=$RESULT_DIR/$seq
> +echo "QA output created by $seq"
> +
> +status=1 # failure is the default!
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +# real QA test starts here
> +_supported_fs ext4
> +
> +_require_scratch
> +_require_command "$DEBUGFS_PROG" debugfs
> +
> +testdir="${SCRATCH_MNT}/testdir"
> +
> +# get block number filename's dir ent
> +# argument 1: filename
> +get_block() {
> + echo $($DEBUGFS_PROG $SCRATCH_DEV -R "dirsearch /testdir $1" 2>> $seqres.full | grep -o -m 1 "phys [0-9]\+" | cut -c 6-)
> +}
> +
> +# get offset of filename's dirent within the block
> +# argument 1: filename
> +get_offset() {
> + echo $($DEBUGFS_PROG $SCRATCH_DEV -R "dirsearch /testdir $1" 2>> $seqres.full | grep -o -m 1 "offset [0-9]\+" | cut -c 8-)
> +}
> +
> +# get record length of dir ent at specified block and offset
> +# argument 1: block
> +# argument 2: offset
> +get_reclen() {
> + echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 4)) --read-bytes=2 -d -An --endian=little | tr -d ' \t\n\r')
When I test this case on centos7, it will report non-supported --endian
option for od command because old od doesn't support this option before
the following patch.
https://github.com/coreutils/coreutils/commit/b370924c03adaef222859061c61be06fc30c9a3e#diff-1cfd938943be810271354b667b12b6ed6ec85481d3fabb6f85d94193bd201235

Is this option neccessary?

Best Regards
Yang Xu.
> +}
> +
> +# reads portion of dirent that should be zero'd out (starting at offset of name_len = 6)
> +# and trims 0s and whitespace
> +# argument 1: block num containing dir ent
> +# argument 2: offset of dir ent within block
> +# argument 3: rec len of dir ent
> +read_dir_ent() {
> + echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 6)) --read-bytes=$(($3 - 6)) -d -An -v | sed -e 's/[0 \t\n\r]//g')
> +}
> +
> +# forces node split on test directory
> +# can be used to convert to htree and to split node on existing htree
> +# looks for jump in directory size as indicator of node split
> +induce_node_split() {
> + _scratch_mount>> $seqres.full 2>&1
> + dir_size="$(stat --printf="%s" $testdir)"
> + while [[ "$(stat --printf="%s" $testdir)" == "$dir_size" ]]; do
> + file_num=$(($file_num + 1))
> + touch $testdir/test"$(printf "%04d" $file_num)"
> + done
> + _scratch_unmount>> $seqres.full 2>&1
> +}
> +
> +#
> +# TEST 1: dir entry fields wiped upon file removal
> +#
> +
> +test_file1="test0001"
> +test_file2="test0002"
> +test_file3="test0003"
> +
> +_scratch_mkfs_sized $((128 * 1024 * 1024))>> $seqres.full 2>&1
> +
> +# create scratch dir for testing
> +# create some files with no name a substr of another name so we can grep later
> +_scratch_mount>> $seqres.full 2>&1
> +blocksize="$(_get_block_size $SCRATCH_MNT)"
> +mkdir $testdir
> +file_num=1
> +for file_num in {1..10}; do
> + touch $testdir/test"$(printf "%04d" $file_num)"
> +done
> +_scratch_unmount>> $seqres.full 2>&1
> +
> +# get block, offset, and rec_len of two test files
> +block1=$(get_block $test_file1)
> +offset1=$(get_offset $test_file1)
> +rec_len1=$(get_reclen $block1 $offset1)
> +
> +block2=$(get_block $test_file2)
> +offset2=$(get_offset $test_file2)
> +rec_len2=$(get_reclen $block2 $offset2)
> +
> +_scratch_mount>> $seqres.full 2>&1
> +rm $testdir/$test_file1
> +_scratch_unmount>> $seqres.full 2>&1
> +
> +# read name_len field to end of dir entry
> +check1=$(read_dir_ent $block1 $offset1 $rec_len1)
> +check2=$(read_dir_ent $block2 $offset2 $rec_len2)
> +
> +# if check is empty, bytes read was all 0's, file data wiped
> +# at this point, check1 should be empty, but check 2 should not be
> +if [ -z "$check1" ]&& [ ! -z "$check2" ]; then
> + echo "Test 1 part 1 passed."
> +else
> + _fail "ERROR (test 1 part 1): metadata not wiped upon removing test file 1"
> +fi
> +
> +_scratch_mount>> $seqres.full 2>&1
> +rm $testdir/$test_file2
> +_scratch_unmount>> $seqres.full 2>&1
> +
> +check2=$(read_dir_ent $block2 $offset2 $rec_len2)
> +
> +# at this point, both should be wiped
> +[ -z "$check2" ]&& echo "Test 1 part 2 passed." || _fail "ERROR (test 1 part 2): metadata not wiped upon removing test file 2"
> +
> +#
> +# TEST 2: old dir entry fields wiped when directory converted to htree
> +#
> +
> +# get original location
> +block1=$(get_block $test_file3)
> +offset1=$(get_offset $test_file3)
> +rec_len1=$(get_reclen $block1 $offset1)
> +
> +# sanity check, ensures not an htree yet
> +check_htree=$($DEBUGFS_PROG $SCRATCH_DEV -R "htree_dump /testdir" 2>&1)
> +if [[ "$check_htree" != *"htree_dump: Not a hash-indexed directory"* ]]; then
> + _fail "ERROR (test 2): already an htree"
> +fi
> +
> +# force conversion to htree
> +induce_node_split
> +
> +# ensure it is now an htree
> +check_htree=$($DEBUGFS_PROG $SCRATCH_DEV -R "htree_dump /testdir" 2>&1)
> +if [[ "$check_htree" == *"htree_dump: Not a hash-indexed directory"* ]]; then
> + _fail "ERROR (test 2): directory was not converted to an htree after creation of many files"
> +fi
> +
> +# check that old data was wiped
> +# (this location is not immediately reused by ext4)
> +check1=$(read_dir_ent $block1 $offset1 $rec_len1)
> +
> +# at this point, check1 should be empty meaning data was wiped
> +[ -z "$check1" ]&& echo "Test 2 passed." || _fail "ERROR (test 2): file metadata not wiped during conversion to htree"
> +
> +#
> +# TEST 3: old dir entries wiped when moved to another block during split_node
> +#
> +
> +# force splitting of a node
> +induce_node_split
> +# use debugfs to get names of two files from block 3
> +hdump=$($DEBUGFS_PROG $SCRATCH_DEV -R "htree_dump /testdir" 2>> $seqres.full)
> +
> +# get line number of "Reading directory block 3"
> +block3_line=$(echo "$hdump" | awk '/Reading directory block 3/{ print NR; exit }')
> +
> +[ -z "$block3_line" ]&& echo "ERROR (test 3): could not find block number 3 after node split"
> +
> +test_file1=$(echo "$hdump" | sed -n "$(($block3_line + 1))"p | cut -d ' ' -f4)
> +test_file2=$(echo "$hdump" | sed -n "$(($block3_line + 2))"p | cut -d ' ' -f4)
> +
> +# check these filenames don't exist in block 1 or 2
> +# get block numbers of first two blocks
> +block1=$(echo "$hdump" | grep -o -m 1 "Reading directory block 1, phys [0-9]\+" | cut -c 33-)
> +block2=$(echo "$hdump" | grep -o -m 1 "Reading directory block 2, phys [0-9]\+" | cut -c 33-)
> +
> +# search all of both these blocks for these file names
> +check1=$(od $SCRATCH_DEV --skip-bytes=$(($block1 * $blocksize)) --read-bytes=$blocksize -c -An -v | tr -d '\\ \t\n\r\v' | grep -e $test_file1 -e $test_file2)
> +check2=$(od $SCRATCH_DEV --skip-bytes=$(($block2 * $blocksize)) --read-bytes=$blocksize -c -An -v | tr -d '\\ \t\n\r\v' | grep -e $test_file1 -e $test_file2)
> +
> +if [ -z "$check1" ]&& [ -z "$check2" ]; then
> + echo "Test 3 passed."
> +else
> + _fail "ERROR (test 3): file name not wiped during node split"
> +fi
> +
> +status=0
> +exit
> diff --git a/tests/ext4/309.out b/tests/ext4/309.out
> new file mode 100644
> index 00000000..e5febaac
> --- /dev/null
> +++ b/tests/ext4/309.out
> @@ -0,0 +1,5 @@
> +QA output created by 309
> +Test 1 part 1 passed.
> +Test 1 part 2 passed.
> +Test 2 passed.
> +Test 3 passed.
> diff --git a/tests/ext4/group b/tests/ext4/group
> index ceda2ba6..e7ad3c24 100644
> --- a/tests/ext4/group
> +++ b/tests/ext4/group
> @@ -59,3 +59,4 @@
> 306 auto rw resize quick
> 307 auto ioctl rw defrag
> 308 auto ioctl rw prealloc quick defrag
> +309 auto quick dir