On 10/14/22 14:28, Darrick J. Wong wrote:
> On Fri, Oct 14, 2022 at 12:09:07PM -0400, Hironori Shiina wrote:
>> Test '-x' option of xfsrestore. With this option, a wrong root inode
>> number in a dump file is corrected. A root inode number can be wrong
>> in a dump created by problematic xfsdump (v3.1.7 - v3.1.9) with
>> bulkstat misuse. In this test, a corrupted dump file is created by
>> overwriting a root inode number in a header.
>>
>> Signed-off-by: Hironori Shiina <shiina.hironori@xxxxxxxxxxx>
>> ---
>> changes since v2:
>> - Use glibc functions to convert endian.
>> - Copy the structure definitions from xfsdump source files.
>> changes since RFC v1:
>> - Skip the test if xfsrestore does not support '-x' flag.
>> - Create a corrupted dump by overwriting a root inode number in a dump
>> file with a new tool instead of checking in a binary dump file.
>>
>> common/dump | 2 +-
>> common/xfs | 6 ++
>> src/Makefile | 2 +-
>> src/fake-dump-rootino.c | 228 ++++++++++++++++++++++++++++++++++++++++
>> tests/xfs/554 | 73 +++++++++++++
>> tests/xfs/554.out | 40 +++++++
>> 6 files changed, 349 insertions(+), 2 deletions(-)
>> create mode 100644 src/fake-dump-rootino.c
>> create mode 100755 tests/xfs/554
>> create mode 100644 tests/xfs/554.out
>>
>> diff --git a/common/dump b/common/dump
>> index 8e0446d9..50b2ba03 100644
>> --- a/common/dump
>> +++ b/common/dump
>> @@ -1003,7 +1003,7 @@ _parse_restore_args()
>> --no-check-quota)
>> do_quota_check=false
>> ;;
>> - -K|-R)
>> + -K|-R|-x)
>> restore_args="$restore_args $1"
>> ;;
>> *)
>> diff --git a/common/xfs b/common/xfs
>> index e1c15d3d..8334880e 100644
>> --- a/common/xfs
>> +++ b/common/xfs
>> @@ -1402,3 +1402,9 @@ _xfs_filter_mkfs()
>> print STDOUT "realtime =RDEV extsz=XXX blocks=XXX, rtextents=XXX\n";
>> }'
>> }
>> +
>> +_require_xfsrestore_xflag()
>> +{
>> + $XFSRESTORE_PROG -h 2>&1 | grep -q -e '-x' || \
>> + _notrun 'xfsrestore does not support -x flag.'
>> +}
>> diff --git a/src/Makefile b/src/Makefile
>> index 5f565e73..afdf6b30 100644
>> --- a/src/Makefile
>> +++ b/src/Makefile
>> @@ -19,7 +19,7 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \
>> t_ofd_locks t_mmap_collision mmap-write-concurrent \
>> t_get_file_time t_create_short_dirs t_create_long_dirs t_enospc \
>> t_mmap_writev_overlap checkpoint_journal mmap-rw-fault allocstale \
>> - t_mmap_cow_memory_failure
>> + t_mmap_cow_memory_failure fake-dump-rootino
>>
>> LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
>> preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
>> diff --git a/src/fake-dump-rootino.c b/src/fake-dump-rootino.c
>> new file mode 100644
>> index 00000000..80797f15
>> --- /dev/null
>> +++ b/src/fake-dump-rootino.c
>> @@ -0,0 +1,228 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/* Copyright (c) 2022 Fujitsu Limited. All Rights Reserved. */
>> +#define _LARGEFILE64_SOURCE
>> +#include <endian.h>
>> +#include <fcntl.h>
>> +#include <stdint.h>
>> +#include <stdio.h>
>> +#include <stdlib.h>
>> +#include <sys/mman.h>
>> +#include <unistd.h>
>> +#include <uuid/uuid.h>
>> +
>> +// Definitions from xfsdump
>> +#define PGSZLOG2 12
>> +#define PGSZ (1 << PGSZLOG2)
>> +#define GLOBAL_HDR_SZ PGSZ
>> +#define GLOBAL_HDR_MAGIC_SZ 8
>> +#define GLOBAL_HDR_STRING_SZ 0x100
>> +#define GLOBAL_HDR_TIME_SZ 4
>> +#define GLOBAL_HDR_UUID_SZ 0x10
>> +typedef int32_t time32_t;
>> +struct global_hdr {
>> + char gh_magic[GLOBAL_HDR_MAGIC_SZ]; /* 8 8 */
>> + /* unique signature of xfsdump */
>> + uint32_t gh_version; /* 4 c */
>> + /* header version */
>> + uint32_t gh_checksum; /* 4 10 */
>> + /* 32-bit unsigned additive inverse of entire header */
>> + time32_t gh_timestamp; /* 4 14 */
>> + /* time32_t of dump */
>> + char gh_pad1[4]; /* 4 18 */
>> + /* alignment */
>> + uint64_t gh_ipaddr; /* 8 20 */
>> + /* from gethostid(2), room for expansion */
>> + uuid_t gh_dumpid; /* 10 30 */
>> + /* ID of dump session */
>> + char gh_pad2[0xd0]; /* d0 100 */
>> + /* alignment */
>> + char gh_hostname[GLOBAL_HDR_STRING_SZ]; /* 100 200 */
>> + /* from gethostname(2) */
>> + char gh_dumplabel[GLOBAL_HDR_STRING_SZ]; /* 100 300 */
>> + /* label of dump session */
>> + char gh_pad3[0x100]; /* 100 400 */
>> + /* padding */
>> + char gh_upper[GLOBAL_HDR_SZ - 0x400]; /* c00 1000 */
>> + /* header info private to upper software layers */
>> +};
>> +typedef struct global_hdr global_hdr_t;
>> +
>> +#define sizeofmember( t, m ) sizeof( ( ( t * )0 )->m )
>> +
>> +#define DRIVE_HDR_SZ sizeofmember(global_hdr_t, gh_upper)
>> +struct drive_hdr {
>> + uint32_t dh_drivecnt; /* 4 4 */
>> + /* number of drives used to dump the fs */
>> + uint32_t dh_driveix; /* 4 8 */
>> + /* 0-based index of the drive used to dump this stream */
>> + int32_t dh_strategyid; /* 4 c */
>> + /* ID of the drive strategy used to produce this dump */
>> + char dh_pad1[0x1f4]; /* 1f4 200 */
>> + /* padding */
>> + char dh_specific[0x200]; /* 200 400 */
>> + /* drive strategy-specific info */
>> + char dh_upper[DRIVE_HDR_SZ - 0x400]; /* 800 c00 */
>> + /* header info private to upper software layers */
>> +};
>> +typedef struct drive_hdr drive_hdr_t;
>> +
>> +#define MEDIA_HDR_SZ sizeofmember(drive_hdr_t, dh_upper)
>> +struct media_hdr {
>> + char mh_medialabel[GLOBAL_HDR_STRING_SZ]; /* 100 100 */
>> + /* label of media object containing file */
>> + char mh_prevmedialabel[GLOBAL_HDR_STRING_SZ]; /* 100 200 */
>> + /* label of upstream media object */
>> + char mh_pad1[GLOBAL_HDR_STRING_SZ]; /* 100 300 */
>> + /* in case more labels needed */
>> + uuid_t mh_mediaid; /* 10 310 */
>> + /* ID of media object */
>> + uuid_t mh_prevmediaid; /* 10 320 */
>> + /* ID of upstream media object */
>> + char mh_pad2[GLOBAL_HDR_UUID_SZ]; /* 10 330 */
>> + /* in case more IDs needed */
>> + uint32_t mh_mediaix; /* 4 334 */
>> + /* 0-based index of this media object within the dump stream */
>> + uint32_t mh_mediafileix; /* 4 338 */
>> + /* 0-based index of this file within this media object */
>> + uint32_t mh_dumpfileix; /* 4 33c */
>> + /* 0-based index of this file within this dump stream */
>> + uint32_t mh_dumpmediafileix; /* 4 340 */
>> + /* 0-based index of file within dump stream and media object */
>> + uint32_t mh_dumpmediaix; /* 4 344 */
>> + /* 0-based index of this dump within the media object */
>> + int32_t mh_strategyid; /* 4 348 */
>> + /* ID of the media strategy used to produce this dump */
>> + char mh_pad3[0x38]; /* 38 380 */
>> + /* padding */
>> + char mh_specific[0x80]; /* 80 400 */
>> + /* media strategy-specific info */
>> + char mh_upper[MEDIA_HDR_SZ - 0x400]; /* 400 800 */
>> + /* header info private to upper software layers */
>> +};
>> +typedef struct media_hdr media_hdr_t;
>> +
>> +#define CONTENT_HDR_SZ sizeofmember(media_hdr_t, mh_upper)
>> +#define CONTENT_HDR_FSTYPE_SZ 16
>> +#define CONTENT_STATSZ 160 /* must match dlog.h DLOG_MULTI_STATSZ */
>> +struct content_hdr {
>> + char ch_mntpnt[GLOBAL_HDR_STRING_SZ]; /* 100 100 */
>> + /* full pathname of fs mount point */
>> + char ch_fsdevice[GLOBAL_HDR_STRING_SZ]; /* 100 200 */
>> + /* full pathname of char device containing fs */
>> + char ch_pad1[GLOBAL_HDR_STRING_SZ]; /* 100 300 */
>> + /* in case another label is needed */
>> + char ch_fstype[CONTENT_HDR_FSTYPE_SZ]; /* 10 310 */
>> + /* from fsid.h */
>> + uuid_t ch_fsid; /* 10 320 */
>> + /* file system uuid */
>> + char ch_pad2[GLOBAL_HDR_UUID_SZ]; /* 10 330 */
>> + /* in case another id is needed */
>> + char ch_pad3[8]; /* 8 338 */
>> + /* padding */
>> + int32_t ch_strategyid; /* 4 33c */
>> + /* ID of the content strategy used to produce this dump */
>> + char ch_pad4[4]; /* 4 340 */
>> + /* alignment */
>> + char ch_specific[0xc0]; /* c0 400 */
>> + /* content strategy-specific info */
>> +};
>> +typedef struct content_hdr content_hdr_t;
>> +
>> +typedef uint64_t xfs_ino_t;
>> +struct startpt {
>> + xfs_ino_t sp_ino; /* first inode to dump */
>> + off64_t sp_offset; /* bytes to skip in file data fork */
>> + int32_t sp_flags;
>> + int32_t sp_pad1;
>> +};
>> +typedef struct startpt startpt_t;
>> +
>> +#define CONTENT_INODE_HDR_SZ sizeofmember(content_hdr_t, ch_specific)
>> +struct content_inode_hdr {
>> + int32_t cih_mediafiletype; /* 4 4 */
>> + /* dump media file type: see #defines below */
>> + int32_t cih_dumpattr; /* 4 8 */
>> + /* dump attributes: see #defines below */
>> + int32_t cih_level; /* 4 c */
>> + /* dump level */
>> + char pad1[4]; /* 4 10 */
>> + /* alignment */
>> + time32_t cih_last_time; /* 4 14 */
>> + /* if an incremental, time of previous dump at a lesser level */
>> + time32_t cih_resume_time; /* 4 18 */
>> + /* if a resumed dump, time of interrupted dump */
>> + xfs_ino_t cih_rootino; /* 8 20 */
>> + /* root inode number */
>> + uuid_t cih_last_id; /* 10 30 */
>> + /* if an incremental, uuid of prev dump */
>> + uuid_t cih_resume_id; /* 10 40 */
>> + /* if a resumed dump, uuid of interrupted dump */
>> + startpt_t cih_startpt; /* 18 58 */
>> + /* starting point of media file contents */
>> + startpt_t cih_endpt; /* 18 70 */
>> + /* starting point of next stream */
>> + uint64_t cih_inomap_hnkcnt; /* 8 78 */
>> +
>> + uint64_t cih_inomap_segcnt; /* 8 80 */
>> +
>> + uint64_t cih_inomap_dircnt; /* 8 88 */
>> +
>> + uint64_t cih_inomap_nondircnt; /* 8 90 */
>> +
>> + xfs_ino_t cih_inomap_firstino; /* 8 98 */
>> +
>> + xfs_ino_t cih_inomap_lastino; /* 8 a0 */
>> +
>> + uint64_t cih_inomap_datasz; /* 8 a8 */
>> + /* bytes of non-metadata dumped */
>> + char cih_pad2[CONTENT_INODE_HDR_SZ - 0xa8]; /* 18 c0 */
>> + /* padding */
>> +};
>> +typedef struct content_inode_hdr content_inode_hdr_t;
>> +// End of definitions from xfsdump
>> +
>> +int main(int argc, char *argv[]) {
>> +
>> + if (argc < 3) {
>> + fprintf(stderr, "Usage: %s <path/to/dumpfile> <fake rootino>\n", argv[0]);
>> + exit(1);
>> + }
>> +
>> + const char *filepath = argv[1];
>> + const uint64_t fake_root_ino = (uint64_t) strtol(argv[2], NULL, 10);
>> +
>> + int fd = open(filepath, O_RDWR);
>> + if (fd < 0) {
>> + perror("open");
>> + exit(1);
>> + }
>> + global_hdr_t *header = mmap(NULL, GLOBAL_HDR_SZ, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
>> + if (header == MAP_FAILED) {
>> + perror("mmap");
>> + exit(1);
>> + }
>> +
>> + uint64_t *rootino_ptr =
>> + &((content_inode_hdr_t *)
>> + ((content_hdr_t *)
>> + ((media_hdr_t *)
>> + ((drive_hdr_t *)
>> + header->gh_upper
>> + )->dh_upper
>> + )->mh_upper
>> + )->ch_specific
>> + )->cih_rootino;
>
> Urrrrrk nested pointer dereferencing.
>
> Oh wow, I didn't realize gh_upper is an opencoded char[].
>
> If you flatten out all that nested pointer dereferencing and
> typecasting, is this what you get?
>
> drive_hdr_t *dh = (drive_hdr_t *)header->gh_upper;
> media_hdr_t *mh = (media_hdr_t *)dh->dh_upper;
> content_hdr_t *ch = (content_hdr_t *)mh->mh_upper;
> content_inode_hdr_t *cih = (content_inode_hdr_t *)ch->ch_specific;
> uint64_t *rootino_ptr = &cih->cih_rootino;
>
> If so, please change the code to do the above so that nobody else has to
> go through that nest of pointer casting.
>
> With that fixed,
> Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
>
I fixed it. Thank you for your review!
---
Hiro
> --D
>
>
>> + int32_t checksum = (int32_t) be32toh(header->gh_checksum);
>> + uint64_t orig_rootino = be64toh(*rootino_ptr);
>> +
>> + // Fake root inode number
>> + *rootino_ptr = htobe64(fake_root_ino);
>> +
>> + // Update checksum along with overwriting rootino.
>> + uint64_t gap = orig_rootino - fake_root_ino;
>> + checksum += (gap >> 32) + (gap & 0x00000000ffffffff);
>> + header->gh_checksum = htobe32(checksum);
>> +
>> + munmap(header, GLOBAL_HDR_SZ);
>> + close(fd);
>> +}
>> diff --git a/tests/xfs/554 b/tests/xfs/554
>> new file mode 100755
>> index 00000000..fcfaa699
>> --- /dev/null
>> +++ b/tests/xfs/554
>> @@ -0,0 +1,73 @@
>> +#! /bin/bash
>> +# SPDX-License-Identifier: GPL-2.0
>> +# Copyright (c) 2022 Fujitsu Limited. All Rights Reserved.
>> +#
>> +# FS QA Test No. 554
>> +#
>> +# Create a filesystem which contains an inode with a lower number
>> +# than the root inode. Set the lower number to a dump file as the root inode
>> +# and ensure that 'xfsrestore -x' handles this wrong inode.
>> +#
>> +. ./common/preamble
>> +_begin_fstest auto quick dump
>> +
>> +# Import common functions.
>> +. ./common/dump
>> +
>> +_supported_fs xfs
>> +_require_xfs_io_command "falloc"
>> +_require_scratch
>> +_require_xfsrestore_xflag
>> +
>> +# A large stripe unit will put the root inode out quite far
>> +# due to alignment, leaving free blocks ahead of it.
>> +_scratch_mkfs_xfs -d sunit=1024,swidth=1024 > $seqres.full 2>&1
>> +
>> +# Mounting /without/ a stripe should allow inodes to be allocated
>> +# in lower free blocks, without the stripe alignment.
>> +_scratch_mount -o sunit=0,swidth=0
>> +
>> +root_inum=$(stat -c %i $SCRATCH_MNT)
>> +
>> +# Consume space after the root inode so that the blocks before
>> +# root look "close" for the next inode chunk allocation
>> +$XFS_IO_PROG -f -c "falloc 0 16m" $SCRATCH_MNT/fillfile
>> +
>> +# And make a bunch of inodes until we (hopefully) get one lower
>> +# than root, in a new inode chunk.
>> +echo "root_inum: $root_inum" >> $seqres.full
>> +for i in $(seq 0 4096) ; do
>> + fname=$SCRATCH_MNT/$(printf "FILE_%03d" $i)
>> + touch $fname
>> + inum=$(stat -c "%i" $fname)
>> + [[ $inum -lt $root_inum ]] && break
>> +done
>> +
>> +echo "created: $inum" >> $seqres.full
>> +
>> +[[ $inum -lt $root_inum ]] || _notrun "Could not set up test"
>> +
>> +# Now try a dump and restore. Cribbed from xfs/068
>> +_create_dumpdir_stress
>> +
>> +echo -n "Before: " >> $seqres.full
>> +_count_dumpdir_files | tee $tmp.before >> $seqres.full
>> +
>> +_do_dump_file
>> +
>> +# Set the wrong root inode number to the dump file
>> +# as problematic xfsdump used to do.
>> +$here/src/fake-dump-rootino $dump_file $inum
>> +
>> +_do_restore_file -x | \
>> +sed -e "s/rootino #${inum}/rootino #FAKENO/g" \
>> + -e "s/# to ${root_inum}/# to ROOTNO/g" \
>> + -e "/entries processed$/s/[0-9][0-9]*/NUM/g"
>> +
>> +echo -n "After: " >> $seqres.full
>> +_count_restoredir_files | tee $tmp.after >> $seqres.full
>> +diff -u $tmp.before $tmp.after
>> +
>> +# success, all done
>> +status=0
>> +exit
>> diff --git a/tests/xfs/554.out b/tests/xfs/554.out
>> new file mode 100644
>> index 00000000..c5e8c4c5
>> --- /dev/null
>> +++ b/tests/xfs/554.out
>> @@ -0,0 +1,40 @@
>> +QA output created by 554
>> +Creating directory system to dump using fsstress.
>> +
>> +-----------------------------------------------
>> +fsstress : -f link=10 -f creat=10 -f mkdir=10 -f truncate=5 -f symlink=10
>> +-----------------------------------------------
>> +Dumping to file...
>> +xfsdump -f DUMP_FILE -M stress_tape_media -L stress_554 SCRATCH_MNT
>> +xfsdump: using file dump (drive_simple) strategy
>> +xfsdump: level 0 dump of HOSTNAME:SCRATCH_MNT
>> +xfsdump: dump date: DATE
>> +xfsdump: session id: ID
>> +xfsdump: session label: "stress_554"
>> +xfsdump: ino map <PHASES>
>> +xfsdump: ino map construction complete
>> +xfsdump: estimated dump size: NUM bytes
>> +xfsdump: /var/xfsdump/inventory created
>> +xfsdump: creating dump session media file 0 (media 0, file 0)
>> +xfsdump: dumping ino map
>> +xfsdump: dumping directories
>> +xfsdump: dumping non-directory files
>> +xfsdump: ending media file
>> +xfsdump: media file size NUM bytes
>> +xfsdump: dump size (non-dir files) : NUM bytes
>> +xfsdump: dump complete: SECS seconds elapsed
>> +xfsdump: Dump Status: SUCCESS
>> +Restoring from file...
>> +xfsrestore -x -f DUMP_FILE -L stress_554 RESTORE_DIR
>> +xfsrestore: using file dump (drive_simple) strategy
>> +xfsrestore: using online session inventory
>> +xfsrestore: searching media for directory dump
>> +xfsrestore: examining media file 0
>> +xfsrestore: reading directories
>> +xfsrestore: found fake rootino #FAKENO, will fix.
>> +xfsrestore: fix root # to ROOTNO (bind mount?)
>> +xfsrestore: NUM directories and NUM entries processed
>> +xfsrestore: directory post-processing
>> +xfsrestore: restoring non-directory files
>> +xfsrestore: restore complete: SECS seconds elapsed
>> +xfsrestore: Restore Status: SUCCESS
>> --
>> 2.37.3
>>
