xfs: test inode allocation state missmatch corruption

There's a situation where the directory structure and the inobt
thinks the inode is free, but the inode on disk thinks it is still
in use. XFS should detect it and prevent the kernel from oopsing on
lookup.

Signed-off-by: Zorro Lang <zlang@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

tests/xfs/490

@@ -0,0 +1,113 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2018 Red Hat Inc.  All Rights Reserved.
+#
+# FS QA Test No. 490
+#
+# Test a corruption when the directory structure and the inobt thinks the inode
+# is free, but the inode on disk thinks it is still in use.
+#
+# This case test same bug (upstream linux commit ee457001ed6c) as xfs/132, but
+# through different code path.
+#
+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.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+
+# Modify as appropriate.
+_supported_fs xfs
+_supported_os Linux
+_require_scratch_nocheck
+_require_xfs_mkfs_finobt
+
+# Skip the verifier "xfs_check_agi_freecount()" which verify the number of free
+# inodes in the AGI is correct, when XFS_DEBUG is enabled
+_require_no_xfs_debug
+
+filter_dmesg()
+{
+	local warn1="Internal error xfs_trans_cancel.*fs/xfs/xfs_trans\.c.*"
+
+	sed -e "s#$warn1#Intentional error in xfs_trans_cancel#"
+}
+
+# If enable free inode B+tree, this case will fail on xfs_dialloc_ag_update_inobt,
+# that's not what we want to test. Due to finobt feature is not necessary for this
+# test, so disable it directly.
+_scratch_mkfs_xfs -m finobt=0 | _filter_mkfs 2>$tmp.mkfs >> $seqres.full
+
+# On V5 filesystem, this case can't trigger bug because it doesn't read inodes
+# we are allocating from disk - it simply overwrites them with new inode
+# information. So use ikeep mount option to stop that.
+source $tmp.mkfs
+mount_opt=""
+if [ $_fs_has_crcs -eq 1 ]; then
+	mount_opt="-o ikeep"
+fi
+
+blksz=$(_scratch_xfs_get_sb_field blocksize)
+agcount=$(_scratch_xfs_get_sb_field agcount)
+
+_scratch_mount $mount_opt
+# Create a directory for later allocation in same AG (AG 0, due to this's an
+# empty XFS for now)
+mkdir $SCRATCH_MNT/dir
+
+# Allocate 1 block for testfile
+$XFS_IO_PROG -fc "pwrite 0 $blksz" -c fsync $SCRATCH_MNT/dir/testfile >> $seqres.full
+inum=`stat -c %i $SCRATCH_MNT/dir/testfile`
+_scratch_unmount
+
+# Find the AG which contains testfile
+agi=`_scratch_xfs_db -c "convert inode $inum agno" | sed -e 's/^.*(\([0-9]*\).*$/\1/g'`
+
+# Due to we only allocate 1 block for testfile, and this's the only one data
+# block we use. So we use single level inobt, So the ${agi}->root->recs[1]
+# should be the only one record points the chunk which contains testfile's
+# inode.
+# An exmaple of inode record is as below:
+#   recs[1] = [startino,freecount,free] 1:[1024,59,0xffffffffffffffe0]
+freecount=$(_scratch_xfs_get_metadata_field "recs[1].freecount" \
+					    "agi $agi" "addr root")
+fmask=$(_scratch_xfs_get_metadata_field "recs[1].free" "agi $agi" "addr root")
+
+# fmask shift right 1 bit, and freecount++, to mark testfile inode as free in
+# inobt. (But the inode itself isn't freed, it still has allocated block)
+freecount="$((freecount + 1))"
+fmask="$((fmask / 2))"
+_scratch_xfs_set_metadata_field "recs[1].freecount" "$freecount" \
+				"agi $agi" "addr root" >/dev/null
+_scratch_xfs_set_metadata_field "recs[1].free" "$fmask" \
+				"agi $agi" "addr root" >/dev/null
+
+# Mount again and create a new inode cover that inode we just 'freed' from inobt
+_scratch_mount $mount_opt
+$XFS_IO_PROG -fc "pwrite 0 $blksz" -c fsync $SCRATCH_MNT/dir/newfile 2>&1 | \
+	grep -i "Structure needs cleaning" | _filter_scratch
+
+# filter a intentional internal errors
+_check_dmesg filter_dmesg
+
+# success, all done
+status=0
+exit

tests/xfs/490.out

@@ -0,0 +1,2 @@
+QA output created by 490
+SCRATCH_MNT/dir/newfile: Structure needs cleaning

tests/xfs/group

@@ -487,3 +487,4 @@
 487 dangerous_fuzzers dangerous_norepair
 488 dangerous_fuzzers dangerous_norepair
 489 dangerous_fuzzers dangerous_norepair
+490 auto quick