linux-stable.git/drivers/md, branch linux-6.2.y

dm: don't lock fs when the map is NULL in process of resume

2023-05-11T14:11:35+00:00

commit 38d11da522aacaa05898c734a1cec86f1e611129 upstream.

Commit fa247089de99 ("dm: requeue IO if mapping table not yet available")
added a detection of whether the mapping table is available in the IO
submission process. If the mapping table is unavailable, it returns
BLK_STS_RESOURCE and requeues the IO.
This can lead to the following deadlock problem:

dm create                                      mount
ioctl(DM_DEV_CREATE_CMD)
ioctl(DM_TABLE_LOAD_CMD)
                               do_mount
                                vfs_get_tree
                                 ext4_get_tree
                                  get_tree_bdev
                                   sget_fc
                                    alloc_super
                                     // got &s->s_umount
                                     down_write_nested(&s->s_umount, ...);
                                   ext4_fill_super
                                    ext4_load_super
                                     ext4_read_bh
                                      submit_bio
                                      // submit and wait io end
ioctl(DM_DEV_SUSPEND_CMD)
dev_suspend
 do_resume
  dm_suspend
   __dm_suspend
    lock_fs
     freeze_bdev
      get_active_super
       grab_super
        // wait for &s->s_umount
        down_write(&s->s_umount);
  dm_swap_table
   __bind
    // set md->map(can't get here)

IO will be continuously requeued while holding the lock since mapping
table is NULL. At the same time, mapping table won't be set since the
lock is not available.
Like request-based DM, bio-based DM also has the same problem.

It's not proper to just abort IO if the mapping table not available.
So clear DM_SKIP_LOCKFS_FLAG when the mapping table is NULL, this
allows the DM table to be loaded and the IO submitted upon resume.

Fixes: fa247089de99 ("dm: requeue IO if mapping table not yet available")
Cc: stable@vger.kernel.org
Signed-off-by: Li Lingfeng 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm ioctl: fix nested locking in table_clear() to remove deadlock concern

2023-05-11T14:11:35+00:00

commit 3d32aaa7e66d5c1479a3c31d6c2c5d45dd0d3b89 upstream.

syzkaller found the following problematic rwsem locking (with write
lock already held):

 down_read+0x9d/0x450 kernel/locking/rwsem.c:1509
 dm_get_inactive_table+0x2b/0xc0 drivers/md/dm-ioctl.c:773
 __dev_status+0x4fd/0x7c0 drivers/md/dm-ioctl.c:844
 table_clear+0x197/0x280 drivers/md/dm-ioctl.c:1537

In table_clear, it first acquires a write lock
https://elixir.bootlin.com/linux/v6.2/source/drivers/md/dm-ioctl.c#L1520
down_write(&_hash_lock);

Then before the lock is released at L1539, there is a path shown above:
table_clear -> __dev_status -> dm_get_inactive_table ->  down_read
https://elixir.bootlin.com/linux/v6.2/source/drivers/md/dm-ioctl.c#L773
down_read(&_hash_lock);

It tries to acquire the same read lock again, resulting in the deadlock
problem.

Fix this by moving table_clear()'s __dev_status() call to after its
up_write(&_hash_lock);

Cc: stable@vger.kernel.org
Reported-by: Zheng Zhang 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm flakey: fix a crash with invalid table line

2023-05-11T14:11:35+00:00

commit 98dba02d9a93eec11bffbb93c7c51624290702d2 upstream.

This command will crash with NULL pointer dereference:
 dmsetup create flakey --table \
  "0 `blockdev --getsize /dev/ram0` flakey /dev/ram0 0 0 1 2 corrupt_bio_byte 512"

Fix the crash by checking if arg_name is non-NULL before comparing it.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm integrity: call kmem_cache_destroy() in dm_integrity_init() error path

2023-05-11T14:11:35+00:00

commit 6b79a428c02769f2a11f8ae76bf866226d134887 upstream.

Otherwise the journal_io_cache will leak if dm_register_target() fails.

Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm clone: call kmem_cache_destroy() in dm_clone_init() error path

2023-05-11T14:11:35+00:00

commit 6827af4a9a9f5bb664c42abf7c11af4978d72201 upstream.

Otherwise the _hydration_cache will leak if dm_register_target() fails.

Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm verity: fix error handling for check_at_most_once on FEC

2023-05-11T14:11:35+00:00

commit e8c5d45f82ce0c238a4817739892fe8897a3dcc3 upstream.

In verity_end_io(), if bi_status is not BLK_STS_OK, it can be return
directly. But if FEC configured, it is desired to correct the data page
through verity_verify_io. And the return value will be converted to
blk_status and passed to verity_finish_io().

BTW, when a bit is set in v->validated_blocks, verity_verify_io() skips
verification regardless of I/O error for the corresponding bio. In this
case, the I/O error could not be returned properly, and as a result,
there is a problem that abnormal data could be read for the
corresponding block.

To fix this problem, when an I/O error occurs, do not skip verification
even if the bit related is set in v->validated_blocks.

Fixes: 843f38d382b1 ("dm verity: add 'check_at_most_once' option to only validate hashes once")
Cc: stable@vger.kernel.org
Reviewed-by: Sungjong Seo 
Signed-off-by: Yeongjin Gil 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

md/raid5: Improve performance for sequential IO

2023-05-11T14:11:33+00:00

commit fc05e06e6098ca2c28f7a10da0e00aeea20fa59e upstream.

Commit 7e55c60acfbb ("md/raid5: Pivot raid5_make_request()") changed the
order in which requests for underlying disks are created. Since for
large sequential IO adding of requests frequently races with md_raid5
thread submitting bios to underlying disks, this results in a change in
IO pattern because intermediate states of new order of request creation
result in more smaller discontiguous requests. For RAID5 on top of three
rotational disks our performance testing revealed this results in
regression in write throughput:

iozone -a -s 131072000 -y 4 -q 8 -i 0 -i 1 -R

before 7e55c60acfbb:
              KB  reclen   write rewrite    read    reread
       131072000       4  493670  525964   524575   513384
       131072000       8  540467  532880   512028   513703

after 7e55c60acfbb:
              KB  reclen   write rewrite    read    reread
       131072000       4  421785  456184   531278   509248
       131072000       8  459283  456354   528449   543834

To reduce the amount of discontiguous requests we can start generating
requests with the stripe with the lowest chunk offset as that has the
best chance of being adjacent to IO queued previously. This improves the
performance to:
              KB  reclen   write rewrite    read    reread
       131072000       4  497682  506317   518043   514559
       131072000       8  514048  501886   506453   504319

restoring big part of the regression.

Fixes: 7e55c60acfbb ("md/raid5: Pivot raid5_make_request()")
Cc: stable@vger.kernel.org # v6.0+
Signed-off-by: Jan Kara 
Reviewed-by: Logan Gunthorpe 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230417171537.17899-1-jack@suse.cz
Signed-off-by: Greg Kroah-Hartman

md/raid10: fix null-ptr-deref in raid10_sync_request

2023-05-11T14:11:33+00:00

commit a405c6f0229526160aa3f177f65e20c86fce84c5 upstream.

init_resync() inits mempool and sets conf->have_replacemnt at the beginning
of sync, close_sync() frees the mempool when sync is completed.

After [1] recovery might be skipped and init_resync() is called but
close_sync() is not. null-ptr-deref occurs with r10bio->dev[i].repl_bio.

The following is one way to reproduce the issue.

  1) create a array, wait for resync to complete, mddev->recovery_cp is set
     to MaxSector.
  2) recovery is woken and it is skipped. conf->have_replacement is set to
     0 in init_resync(). close_sync() not called.
  3) some io errors and rdev A is set to WantReplacement.
  4) a new device is added and set to A's replacement.
  5) recovery is woken, A have replacement, but conf->have_replacemnt is
     0. r10bio->dev[i].repl_bio will not be alloced and null-ptr-deref
     occurs.

Fix it by not calling init_resync() if recovery skipped.

[1] commit 7e83ccbecd60 ("md/raid10: Allow skipping recovery when clean arrays are assembled")
Fixes: 7e83ccbecd60 ("md/raid10: Allow skipping recovery when clean arrays are assembled")
Cc: stable@vger.kernel.org
Signed-off-by: Li Nan 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230222041000.3341651-3-linan666@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman

md/raid10: don't call bio_start_io_acct twice for bio which experienced read error

2023-05-11T14:11:15+00:00

[ Upstream commit 7cddb055bfda5f7b0be931e8ea750fc28bc18a27 ]

handle_read_error() will resumit r10_bio by raid10_read_request(), which
will call bio_start_io_acct() again, while bio_end_io_acct() will only
be called once.

Fix the problem by don't account io again from handle_read_error().

Fixes: 528bc2cf2fcc ("md/raid10: enable io accounting")
Suggested-by: Song Liu 
Signed-off-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230314012258.2395894-1-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin

md/raid10: fix memleak of md thread

2023-05-11T14:11:15+00:00

[ Upstream commit f0ddb83da3cbbf8a1f9087a642c448ff52ee9abd ]

In raid10_run(), if setup_conf() succeed and raid10_run() failed before
setting 'mddev->thread', then in the error path 'conf->thread' is not
freed.

Fix the problem by setting 'mddev->thread' right after setup_conf().

Fixes: 43a521238aca ("md-cluster: choose correct label when clustered layout is not supported")
Signed-off-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230310073855.1337560-7-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin