[PATCH 2/2] f2fs/022: do sanity check on footer of non inode dnode

[Chao Yu <chao@kernel.org>]

This is a regression test:
1. create foo & bar
2. write 8M data to foo
3. use inject.f2fs to inject i_nid[0] of foo w/ ino of bar
4. fpunch in foo w/ specified range

If we haven't applied kernel patch ("f2fs: fix to do sanity check on
node footer for non inode dnode"), f2fs may missed to do sanity check
on corrupted dnode, result in panic in step 4).

Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
---
 tests/f2fs/022     | 52 ++++++++++++++++++++++++++++++++++++++++++++++
 tests/f2fs/022.out |  2 ++
 2 files changed, 54 insertions(+)
 create mode 100755 tests/f2fs/022
 create mode 100644 tests/f2fs/022.out

diff --git a/tests/f2fs/022 b/tests/f2fs/022
new file mode 100755
index 00000000..a5e19a71
--- /dev/null
+++ b/tests/f2fs/022
@@ -0,0 +1,52 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2025 Chao Yu.  All Rights Reserved.
+#
+# FS QA Test No. f2fs/022
+#
+# This is a regression test:
+# 1. create foo & bar
+# 2. write 8M data to foo
+# 3. use inject.f2fs to inject i_nid[0] of foo w/ ino of bar
+# 4. fpunch in foo w/ specified range
+#
+. ./common/preamble
+_begin_fstest auto quick rw
+
+. ./common/attr
+
+_fixed_by_kernel_commit xxxxxxxxxxxx \
+	"f2fs: fix to do sanity check on node footer for non inode dnode"
+
+_require_scratch_nocheck
+_require_command "$F2FS_INJECT_PROG" inject.f2fs
+_require_xfs_io_command "fpunch"
+_require_kernel_config CONFIG_F2FS_CHECK_FS
+
+# remove all mkfs options to avoid layout change of on-disk inode
+export MKFS_OPTIONS=""
+
+foo_path=$SCRATCH_MNT/foo
+bar_path=$SCRATCH_MNT/bar
+
+_scratch_mkfs >> $seqres.full
+_scratch_mount
+
+touch $foo_path
+touch $bar_path
+$XFS_IO_PROG $foo_path -c "pwrite 0 8M" >> $seqres.full
+sync
+foo_ino=`stat -c '%i' $foo_path`
+bar_ino=`stat -c '%i' $bar_path`
+_scratch_unmount
+
+# inject foo inode to replace i_nid[0] w/ to bar ino
+$F2FS_INJECT_PROG --node --mb i_nid --nid $foo_ino --idx 0 --val $bar_ino $SCRATCH_DEV >> $seqres.full || _fail "failed to inject"
+
+_scratch_mount
+# expect to trigger panic
+$XFS_IO_PROG $foo_path -c "fpunch 6984k 4k"
+_scratch_unmount
+
+status=0
+exit
diff --git a/tests/f2fs/022.out b/tests/f2fs/022.out
new file mode 100644
index 00000000..5307e3d7
--- /dev/null
+++ b/tests/f2fs/022.out
@@ -0,0 +1,2 @@
+QA output created by 022
+fallocate: Structure needs cleaning
-- 
2.49.0