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+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2025 Chao Yu. All Rights Reserved.
+#
+# FS QA Test No. f2fs/009
+#
+# This is a regression test to check whether fsck can handle corrupted
+# nlinks correctly, it uses inject.f2fs to inject nlinks w/ wrong value,
+# and expects fsck.f2fs can detect such corruption and do the repair.
+#
+. ./common/preamble
+_begin_fstest auto quick
+
+if [ ! -x "$(type -P socket)" ]; then
+ _notrun "Couldn't find socket"
+fi
+
+_require_scratch
+_require_command "$F2FS_INJECT_PROG" inject.f2fs
+
+_fixed_by_git_commit f2fs-tools 958cd6e \
+ "fsck.f2fs: support to repair corrupted i_links"
+
+filename=$SCRATCH_MNT/foo
+hardlink=$SCRATCH_MNT/bar
+
+_cleanup()
+{
+ if [ -n "$pid" ]; then
+ kill $pid &> /dev/null
+ wait
+ fi
+ cd /
+ rm -r -f $tmp.*
+}
+
+for ((i=0;i<14;i++)) do
+ echo "round: " $i >> $seqres.full
+
+ _scratch_mkfs >> $seqres.full
+ _scratch_mount
+
+ if [ $i == 0 ]; then
+ touch $filename
+ ino=`stat -c '%i' $filename`
+ nlink=0
+ elif [ $i == 1 ]; then
+ mkdir $filename
+ ino=`stat -c '%i' $filename`
+ nlink=1
+ elif [ $i == 2 ]; then
+ mknod $filename c 9 0
+ ino=`stat -c '%i' $filename`
+ nlink=0
+ elif [ $i == 3 ]; then
+ mknod $filename b 8 0
+ ino=`stat -c '%i' $filename`
+ nlink=0
+ elif [ $i == 4 ]; then
+ mkfifo $filename
+ ino=`stat -c '%i' $filename`
+ nlink=0
+ elif [ $i == 5 ]; then
+ socket -s $filename >> $seqres.full 2>&1 &
+ pid=$!
+ sleep 2
+ ino=`stat -c '%i' $filename`
+ kill $pid >> $seqres.full 2>&1
+ nlink=0
+ elif [ $i == 6 ]; then
+ ln -s $SCRATCH_MNT/empty $filename
+ ino=`stat -c '%i' $filename`
+ nlink=0
+ elif [ $i == 7 ]; then
+ # orphan inode
+ touch $filename
+ ino=`stat -c '%i' $filename`
+ $F2FS_IO_PROG write 1 0 1 zero atomic_commit $filename 5000 >> $seqres.full 2>&1 &
+ stat $filename >> $seqres.full
+ rm $filename
+ $F2FS_IO_PROG shutdown 1 $SCRATCH_MNT/ >> $seqres.full
+ sleep 6
+ nlink=1
+ elif [ $i == 8 ]; then
+ # hardlink on file
+ touch $filename
+ ino=`stat -c '%i' $filename`
+ ln $filename $hardlink
+ nlink=0
+ elif [ $i == 9 ]; then
+ # hardlink on charactor
+ mknod $filename c 9 0
+ ino=`stat -c '%i' $filename`
+ ln $filename $hardlink
+ nlink=0
+ elif [ $i == 10 ]; then
+ # hardlink on blockdev
+ mknod $filename b 8 0
+ ino=`stat -c '%i' $filename`
+ ln $filename $hardlink
+ nlink=0
+ elif [ $i == 11 ]; then
+ # hardlink on pipe
+ mkfifo $filename
+ ino=`stat -c '%i' $filename`
+ ln $filename $hardlink
+ nlink=0
+ elif [ $i == 12 ]; then
+ # hardlink on socket
+ socket -s $filename >> $seqres.full 2>&1 &
+ pid=$!
+ sleep 2
+ ino=`stat -c '%i' $filename`
+ kill $pid >> $seqres.full 2>&1
+ ln $filename $hardlink
+ nlink=0
+ elif [ $i == 13 ]; then
+ # hardlink on symlink
+ ln -s $SCRATCH_MNT/empty $filename
+ ino=`stat -c '%i' $filename`
+ ln $filename $hardlink
+ nlink=0
+ fi
+
+ if [ $i != 7 ]; then
+ stat $SCRATCH_MNT/* >> $seqres.full
+ fi
+ echo "ino:"$ino >> $seqres.full
+ echo "nlink:"$nlink >> $seqres.full
+
+ _scratch_unmount
+
+ $F2FS_INJECT_PROG --node --mb i_links --nid $ino --val $nlink $SCRATCH_DEV \
+ >> $seqres.full || _fail "fail to inject"
+
+ _check_scratch_fs >> $seqres.full 2>&1 && _fail "can't find corruption"
+ _repair_scratch_fs >> $seqres.full
+ _check_scratch_fs >> $seqres.full 2>&1 || _fail "fsck can't fix corruption"
+
+ _scratch_mount
+ _scratch_unmount
+done
+
+echo "Silence is golden"
+
+status=0
+exit
new file mode 100644
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+QA output created by 009
+Silence is golden
This is a regression test to check whether fsck can handle corrupted nlinks correctly, it uses inject.f2fs to inject nlinks w/ wrong value, and expects fsck.f2fs can detect such corruption and do the repair. Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Chao Yu <chao@kernel.org> --- v4: - remove unnecessary "_require_command fsck.f2fs" - clean up _fixed_by_git_commit line - fix to clean all tmp files in _cleanup tests/f2fs/009 | 147 +++++++++++++++++++++++++++++++++++++++++++++ tests/f2fs/009.out | 2 + 2 files changed, 149 insertions(+) create mode 100755 tests/f2fs/009 create mode 100644 tests/f2fs/009.out