linux-stable.git/drivers/md, branch v5.4.48

dm crypt: avoid truncating the logical block size

2020-06-22T07:31:21+00:00

commit 64611a15ca9da91ff532982429c44686f4593b5f upstream.

queue_limits::logical_block_size got changed from unsigned short to
unsigned int, but it was forgotten to update crypt_io_hints() to use the
new type.  Fix it.

Fixes: ad6bf88a6c19 ("block: fix an integer overflow in logical block size")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers 
Reviewed-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

bcache: fix refcount underflow in bcache_device_free()

2020-06-22T07:31:09+00:00

[ Upstream commit 86da9f736740eba602389908574dfbb0f517baa5 ]

The problematic code piece in bcache_device_free() is,

 785 static void bcache_device_free(struct bcache_device *d)
 786 {
 787     struct gendisk *disk = d->disk;
 [snipped]
 799     if (disk) {
 800             if (disk->flags & GENHD_FL_UP)
 801                     del_gendisk(disk);
 802
 803             if (disk->queue)
 804                     blk_cleanup_queue(disk->queue);
 805
 806             ida_simple_remove(&bcache_device_idx,
 807                               first_minor_to_idx(disk->first_minor));
 808             put_disk(disk);
 809         }
 [snipped]
 816 }

At line 808, put_disk(disk) may encounter kobject refcount of 'disk'
being underflow.

Here is how to reproduce the issue,
- Attche the backing device to a cache device and do random write to
  make the cache being dirty.
- Stop the bcache device while the cache device has dirty data of the
  backing device.
- Only register the backing device back, NOT register cache device.
- The bcache device node /dev/bcache0 won't show up, because backing
  device waits for the cache device shows up for the missing dirty
  data.
- Now echo 1 into /sys/fs/bcache/pendings_cleanup, to stop the pending
  backing device.
- After the pending backing device stopped, use 'dmesg' to check kernel
  message, a use-after-free warning from KASA reported the refcount of
  kobject linked to the 'disk' is underflow.

The dropping refcount at line 808 in the above code piece is added by
add_disk(d->disk) in bch_cached_dev_run(). But in the above condition
the cache device is not registered, bch_cached_dev_run() has no chance
to be called and the refcount is not added. The put_disk() for a non-
added refcount of gendisk kobject triggers a underflow warning.

This patch checks whether GENHD_FL_UP is set in disk->flags, if it is
not set then the bcache device was not added, don't call put_disk()
and the the underflow issue can be avoided.

Signed-off-by: Coly Li 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

raid5: remove gfp flags from scribble_alloc()

2020-06-22T07:31:06+00:00

[ Upstream commit ba54d4d4d2844c234f1b4692bd8c9e0f833c8a54 ]

Using GFP_NOIO flag to call scribble_alloc() from resize_chunk() does
not have the expected behavior. kvmalloc_array() inside scribble_alloc()
which receives the GFP_NOIO flag will eventually call kmalloc_node() to
allocate physically continuous pages.

Now we have memalloc scope APIs in mddev_suspend()/mddev_resume() to
prevent memory reclaim I/Os during raid array suspend context, calling
to kvmalloc_array() with GFP_KERNEL flag may avoid deadlock of recursive
I/O as expected.

This patch removes the useless gfp flags from parameters list of
scribble_alloc(), and call kvmalloc_array() with GFP_KERNEL flag. The
incorrect GFP_NOIO flag does not exist anymore.

Fixes: b330e6a49dc3 ("md: convert to kvmalloc")
Suggested-by: Michal Hocko 
Signed-off-by: Coly Li 
Signed-off-by: Song Liu 
Signed-off-by: Sasha Levin

md: don't flush workqueue unconditionally in md_open

2020-06-22T07:31:05+00:00

[ Upstream commit f6766ff6afff70e2aaf39e1511e16d471de7c3ae ]

We need to check mddev->del_work before flush workqueu since the purpose
of flush is to ensure the previous md is disappeared. Otherwise the similar
deadlock appeared if LOCKDEP is enabled, it is due to md_open holds the
bdev->bd_mutex before flush workqueue.

kernel: [  154.522645] ======================================================
kernel: [  154.522647] WARNING: possible circular locking dependency detected
kernel: [  154.522650] 5.6.0-rc7-lp151.27-default #25 Tainted: G           O
kernel: [  154.522651] ------------------------------------------------------
kernel: [  154.522653] mdadm/2482 is trying to acquire lock:
kernel: [  154.522655] ffff888078529128 ((wq_completion)md_misc){+.+.}, at: flush_workqueue+0x84/0x4b0
kernel: [  154.522673]
kernel: [  154.522673] but task is already holding lock:
kernel: [  154.522675] ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522691]
kernel: [  154.522691] which lock already depends on the new lock.
kernel: [  154.522691]
kernel: [  154.522694]
kernel: [  154.522694] the existing dependency chain (in reverse order) is:
kernel: [  154.522696]
kernel: [  154.522696] -> #4 (&bdev->bd_mutex){+.+.}:
kernel: [  154.522704]        __mutex_lock+0x87/0x950
kernel: [  154.522706]        __blkdev_get+0x79/0x590
kernel: [  154.522708]        blkdev_get+0x65/0x140
kernel: [  154.522709]        blkdev_get_by_dev+0x2f/0x40
kernel: [  154.522716]        lock_rdev+0x3d/0x90 [md_mod]
kernel: [  154.522719]        md_import_device+0xd6/0x1b0 [md_mod]
kernel: [  154.522723]        new_dev_store+0x15e/0x210 [md_mod]
kernel: [  154.522728]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522732]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522735]        vfs_write+0xad/0x1a0
kernel: [  154.522737]        ksys_write+0xa4/0xe0
kernel: [  154.522745]        do_syscall_64+0x64/0x2b0
kernel: [  154.522748]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522749]
kernel: [  154.522749] -> #3 (&mddev->reconfig_mutex){+.+.}:
kernel: [  154.522752]        __mutex_lock+0x87/0x950
kernel: [  154.522756]        new_dev_store+0xc9/0x210 [md_mod]
kernel: [  154.522759]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522761]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522763]        vfs_write+0xad/0x1a0
kernel: [  154.522765]        ksys_write+0xa4/0xe0
kernel: [  154.522767]        do_syscall_64+0x64/0x2b0
kernel: [  154.522769]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522770]
kernel: [  154.522770] -> #2 (kn->count#253){++++}:
kernel: [  154.522775]        __kernfs_remove+0x253/0x2c0
kernel: [  154.522778]        kernfs_remove+0x1f/0x30
kernel: [  154.522780]        kobject_del+0x28/0x60
kernel: [  154.522783]        mddev_delayed_delete+0x24/0x30 [md_mod]
kernel: [  154.522786]        process_one_work+0x2a7/0x5f0
kernel: [  154.522788]        worker_thread+0x2d/0x3d0
kernel: [  154.522793]        kthread+0x117/0x130
kernel: [  154.522795]        ret_from_fork+0x3a/0x50
kernel: [  154.522796]
kernel: [  154.522796] -> #1 ((work_completion)(&mddev->del_work)){+.+.}:
kernel: [  154.522800]        process_one_work+0x27e/0x5f0
kernel: [  154.522802]        worker_thread+0x2d/0x3d0
kernel: [  154.522804]        kthread+0x117/0x130
kernel: [  154.522806]        ret_from_fork+0x3a/0x50
kernel: [  154.522807]
kernel: [  154.522807] -> #0 ((wq_completion)md_misc){+.+.}:
kernel: [  154.522813]        __lock_acquire+0x1392/0x1690
kernel: [  154.522816]        lock_acquire+0xb4/0x1a0
kernel: [  154.522818]        flush_workqueue+0xab/0x4b0
kernel: [  154.522821]        md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522823]        __blkdev_get+0xea/0x590
kernel: [  154.522825]        blkdev_get+0x65/0x140
kernel: [  154.522828]        do_dentry_open+0x1d1/0x380
kernel: [  154.522831]        path_openat+0x567/0xcc0
kernel: [  154.522834]        do_filp_open+0x9b/0x110
kernel: [  154.522836]        do_sys_openat2+0x201/0x2a0
kernel: [  154.522838]        do_sys_open+0x57/0x80
kernel: [  154.522840]        do_syscall_64+0x64/0x2b0
kernel: [  154.522842]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522844]
kernel: [  154.522844] other info that might help us debug this:
kernel: [  154.522844]
kernel: [  154.522846] Chain exists of:
kernel: [  154.522846]   (wq_completion)md_misc --> &mddev->reconfig_mutex --> &bdev->bd_mutex
kernel: [  154.522846]
kernel: [  154.522850]  Possible unsafe locking scenario:
kernel: [  154.522850]
kernel: [  154.522852]        CPU0                    CPU1
kernel: [  154.522853]        ----                    ----
kernel: [  154.522854]   lock(&bdev->bd_mutex);
kernel: [  154.522856]                                lock(&mddev->reconfig_mutex);
kernel: [  154.522858]                                lock(&bdev->bd_mutex);
kernel: [  154.522860]   lock((wq_completion)md_misc);
kernel: [  154.522861]
kernel: [  154.522861]  *** DEADLOCK ***
kernel: [  154.522861]
kernel: [  154.522864] 1 lock held by mdadm/2482:
kernel: [  154.522865]  #0: ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522868]
kernel: [  154.522868] stack backtrace:
kernel: [  154.522873] CPU: 1 PID: 2482 Comm: mdadm Tainted: G           O      5.6.0-rc7-lp151.27-default #25
kernel: [  154.522875] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
kernel: [  154.522878] Call Trace:
kernel: [  154.522881]  dump_stack+0x8f/0xcb
kernel: [  154.522884]  check_noncircular+0x194/0x1b0
kernel: [  154.522888]  ? __lock_acquire+0x1392/0x1690
kernel: [  154.522890]  __lock_acquire+0x1392/0x1690
kernel: [  154.522893]  lock_acquire+0xb4/0x1a0
kernel: [  154.522895]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522898]  flush_workqueue+0xab/0x4b0
kernel: [  154.522900]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522905]  ? md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522908]  md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522910]  __blkdev_get+0xea/0x590
kernel: [  154.522912]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522914]  blkdev_get+0x65/0x140
kernel: [  154.522916]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522918]  do_dentry_open+0x1d1/0x380
kernel: [  154.522921]  path_openat+0x567/0xcc0
kernel: [  154.522923]  ? __lock_acquire+0x380/0x1690
kernel: [  154.522926]  do_filp_open+0x9b/0x110
kernel: [  154.522929]  ? __alloc_fd+0xe5/0x1f0
kernel: [  154.522935]  ? kmem_cache_alloc+0x28c/0x630
kernel: [  154.522939]  ? do_sys_openat2+0x201/0x2a0
kernel: [  154.522941]  do_sys_openat2+0x201/0x2a0
kernel: [  154.522944]  do_sys_open+0x57/0x80
kernel: [  154.522946]  do_syscall_64+0x64/0x2b0
kernel: [  154.522948]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522951] RIP: 0033:0x7f98d279d9ae

And md_alloc also flushed the same workqueue, but the thing is different
here. Because all the paths call md_alloc don't hold bdev->bd_mutex, and
the flush is necessary to avoid race condition, so leave it as it is.

Signed-off-by: Guoqing Jiang 
Signed-off-by: Song Liu 
Signed-off-by: Sasha Levin

dm multipath: use updated MPATHF_QUEUE_IO on mapping for bio-based mpath

2020-05-06T06:15:10+00:00

commit 5686dee34dbfe0238c0274e0454fa0174ac0a57a upstream.

When adding devices that don't have a scsi_dh on a BIO based multipath,
I was able to consistently hit the warning below and lock-up the system.

The problem is that __map_bio reads the flag before it potentially being
modified by choose_pgpath, and ends up using the older value.

The WARN_ON below is not trivially linked to the issue. It goes like
this: The activate_path delayed_work is not initialized for non-scsi_dh
devices, but we always set MPATHF_QUEUE_IO, asking for initialization.
That is fine, since MPATHF_QUEUE_IO would be cleared in choose_pgpath.
Nevertheless, only for BIO-based mpath, we cache the flag before calling
choose_pgpath, and use the older version when deciding if we should
initialize the path.  Therefore, we end up trying to initialize the
paths, and calling the non-initialized activate_path work.

[   82.437100] ------------[ cut here ]------------
[   82.437659] WARNING: CPU: 3 PID: 602 at kernel/workqueue.c:1624
  __queue_delayed_work+0x71/0x90
[   82.438436] Modules linked in:
[   82.438911] CPU: 3 PID: 602 Comm: systemd-udevd Not tainted 5.6.0-rc6+ #339
[   82.439680] RIP: 0010:__queue_delayed_work+0x71/0x90
[   82.440287] Code: c1 48 89 4a 50 81 ff 00 02 00 00 75 2a 4c 89 cf e9
94 d6 07 00 e9 7f e9 ff ff 0f 0b eb c7 0f 0b 48 81 7a 58 40 74 a8 94 74
a7 <0f> 0b 48 83 7a 48 00 74 a5 0f 0b eb a1 89 fe 4c 89 cf e9 c8 c4 07
[   82.441719] RSP: 0018:ffffb738803977c0 EFLAGS: 00010007
[   82.442121] RAX: ffffa086389f9740 RBX: 0000000000000002 RCX: 0000000000000000
[   82.442718] RDX: ffffa086350dd930 RSI: ffffa0863d76f600 RDI: 0000000000000200
[   82.443484] RBP: 0000000000000200 R08: 0000000000000000 R09: ffffa086350dd970
[   82.444128] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa086350dd930
[   82.444773] R13: ffffa0863d76f600 R14: 0000000000000000 R15: ffffa08636738008
[   82.445427] FS:  00007f6abfe9dd40(0000) GS:ffffa0863dd80000(0000) knlGS:00000
[   82.446040] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   82.446478] CR2: 0000557d288db4e8 CR3: 0000000078b36000 CR4: 00000000000006e0
[   82.447104] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   82.447561] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   82.448012] Call Trace:
[   82.448164]  queue_delayed_work_on+0x6d/0x80
[   82.448472]  __pg_init_all_paths+0x7b/0xf0
[   82.448714]  pg_init_all_paths+0x26/0x40
[   82.448980]  __multipath_map_bio.isra.0+0x84/0x210
[   82.449267]  __map_bio+0x3c/0x1f0
[   82.449468]  __split_and_process_non_flush+0x14a/0x1b0
[   82.449775]  __split_and_process_bio+0xde/0x340
[   82.450045]  ? dm_get_live_table+0x5/0xb0
[   82.450278]  dm_process_bio+0x98/0x290
[   82.450518]  dm_make_request+0x54/0x120
[   82.450778]  generic_make_request+0xd2/0x3e0
[   82.451038]  ? submit_bio+0x3c/0x150
[   82.451278]  submit_bio+0x3c/0x150
[   82.451492]  mpage_readpages+0x129/0x160
[   82.451756]  ? bdev_evict_inode+0x1d0/0x1d0
[   82.452033]  read_pages+0x72/0x170
[   82.452260]  __do_page_cache_readahead+0x1ba/0x1d0
[   82.452624]  force_page_cache_readahead+0x96/0x110
[   82.452903]  generic_file_read_iter+0x84f/0xae0
[   82.453192]  ? __seccomp_filter+0x7c/0x670
[   82.453547]  new_sync_read+0x10e/0x190
[   82.453883]  vfs_read+0x9d/0x150
[   82.454172]  ksys_read+0x65/0xe0
[   82.454466]  do_syscall_64+0x4e/0x210
[   82.454828]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[...]
[   82.462501] ---[ end trace bb39975e9cf45daa ]---

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

dm writecache: fix data corruption when reloading the target

2020-05-06T06:15:10+00:00

commit 31b22120194b5c0d460f59e0c98504de1d3f1f14 upstream.

The dm-writecache reads metadata in the target constructor. However, when
we reload the target, there could be another active instance running on
the same device. This is the sequence of operations when doing a reload:

1. construct new target
2. suspend old target
3. resume new target
4. destroy old target

Metadata that were written by the old target between steps 1 and 2 would
not be visible by the new target.

Fix the data corruption by loading the metadata in the resume handler.

Also, validate block_size is at least as large as both the devices'
logical block size and only read 1 block from the metadata during
target constructor -- no need to read entirety of metadata now that it
is done during resume.

Fixes: 48debafe4f2f ("dm: add writecache target")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm verity fec: fix hash block number in verity_fec_decode

2020-05-06T06:15:10+00:00

commit ad4e80a639fc61d5ecebb03caa5cdbfb91fcebfc upstream.

The error correction data is computed as if data and hash blocks
were concatenated. But hash block number starts from v->hash_start.
So, we have to calculate hash block number based on that.

Fixes: a739ff3f543af ("dm verity: add support for forward error correction")
Cc: stable@vger.kernel.org
Signed-off-by: Sunwook Eom 
Reviewed-by: Sami Tolvanen 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm clone: Add missing casts to prevent overflows and data corruption

2020-04-17T08:50:24+00:00

[ Upstream commit 9fc06ff56845cc5ccafec52f545fc2e08d22f849 ]

Add missing casts when converting from regions to sectors.

In case BITS_PER_LONG == 32, the lack of the appropriate casts can lead
to overflows and miscalculation of the device sector.

As a result, we could end up discarding and/or copying the wrong parts
of the device, thus corrupting the device's data.

Fixes: 7431b7835f55 ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nikos Tsironis 
Signed-off-by: Mike Snitzer 
Signed-off-by: Sasha Levin

dm clone: Fix handling of partial region discards

2020-04-17T08:50:24+00:00

[ Upstream commit 4b5142905d4ff58a4b93f7c8eaa7ba829c0a53c9 ]

There is a bug in the way dm-clone handles discards, which can lead to
discarding the wrong blocks or trying to discard blocks beyond the end
of the device.

This could lead to data corruption, if the destination device indeed
discards the underlying blocks, i.e., if the discard operation results
in the original contents of a block to be lost.

The root of the problem is the code that calculates the range of regions
covered by a discard request and decides which regions to discard.

Since dm-clone handles the device in units of regions, we don't discard
parts of a region, only whole regions.

The range is calculated as:

    rs = dm_sector_div_up(bio->bi_iter.bi_sector, clone->region_size);
    re = bio_end_sector(bio) >> clone->region_shift;

, where 'rs' is the first region to discard and (re - rs) is the number
of regions to discard.

The bug manifests when we try to discard part of a single region, i.e.,
when we try to discard a block with size < region_size, and the discard
request both starts at an offset with respect to the beginning of that
region and ends before the end of the region.

The root cause is the following comparison:

  if (rs == re)
    // skip discard and complete original bio immediately

, which doesn't take into account that 'rs' might be greater than 're'.

Thus, we then issue a discard request for the wrong blocks, instead of
skipping the discard all together.

Fix the check to also take into account the above case, so we don't end
up discarding the wrong blocks.

Also, add some range checks to dm_clone_set_region_hydrated() and
dm_clone_cond_set_range(), which update dm-clone's region bitmap.

Note that the aforementioned bug doesn't cause invalid memory accesses,
because dm_clone_is_range_hydrated() returns True for this case, so the
checks are just precautionary.

Fixes: 7431b7835f55 ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nikos Tsironis 
Signed-off-by: Mike Snitzer 
Signed-off-by: Sasha Levin

dm clone: replace spin_lock_irqsave with spin_lock_irq

2020-04-17T08:50:23+00:00

[ Upstream commit 6ca43ed8376a51afec790dd484a51804ade4352a ]

If we are in a place where it is known that interrupts are enabled,
functions spin_lock_irq/spin_unlock_irq should be used instead of
spin_lock_irqsave/spin_unlock_irqrestore.

spin_lock_irq and spin_unlock_irq are faster because they don't need to
push and pop the flags register.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Nikos Tsironis 
Signed-off-by: Mike Snitzer 
Signed-off-by: Sasha Levin