linux-stable.git/drivers/md, branch v5.4.286

md/raid10: improve code of mrdev in raid10_sync_request

2024-11-17T13:58:53+00:00

commit 59f8f0b54c8ffb4521f6bbd1cb6f4dfa5022e75e upstream.

'need_recover' and 'mrdev' are equivalent in raid10_sync_request(), and
inc mrdev->nr_pending is unreasonable if don't need recovery. Replace
'need_recover' with 'mrdev', and only inc nr_pending when needed.

Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230527072218.2365857-3-linan666@huaweicloud.com
Cc: Hagar Gamal Halim 
Signed-off-by: Greg Kroah-Hartman

dm-unstriped: cast an operand to sector_t to prevent potential uint32_t overflow

2024-11-17T13:58:51+00:00

commit 5a4510c762fc04c74cff264cd4d9e9f5bf364bae upstream.

This was found by a static analyzer.
There may be a potential integer overflow issue in
unstripe_ctr(). uc->unstripe_offset and uc->unstripe_width are
defined as "sector_t"(uint64_t), while uc->unstripe,
uc->chunk_size and uc->stripes are all defined as "uint32_t".
The result of the calculation will be limited to "uint32_t"
without correct casting.
So, we recommend adding an extra cast to prevent potential
integer overflow.

Fixes: 18a5bf270532 ("dm: add unstriped target")
Signed-off-by: Zichen Xie 
Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

dm cache: fix potential out-of-bounds access on the first resume

2024-11-17T13:58:51+00:00

commit c0ade5d98979585d4f5a93e4514c2e9a65afa08d upstream.

Out-of-bounds access occurs if the fast device is expanded unexpectedly
before the first-time resume of the cache table. This happens because
expanding the fast device requires reloading the cache table for
cache_create to allocate new in-core data structures that fit the new
size, and the check in cache_preresume is not performed during the
first resume, leading to the issue.

Reproduce steps:

1. prepare component devices:

dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc 262144"
dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct

2. load a cache table of 512 cache blocks, and deliberately expand the
   fast device before resuming the cache, making the in-core data
   structures inadequate.

dmsetup create cache --notable
dmsetup reload cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"
dmsetup reload cdata --table "0 131072 linear /dev/sdc 8192"
dmsetup resume cdata
dmsetup resume cache

3. suspend the cache to write out the in-core dirty bitset and hint
   array, leading to out-of-bounds access to the dirty bitset at offset
   0x40:

dmsetup suspend cache

KASAN reports:

  BUG: KASAN: vmalloc-out-of-bounds in is_dirty_callback+0x2b/0x80
  Read of size 8 at addr ffffc90000085040 by task dmsetup/90

  (...snip...)
  The buggy address belongs to the virtual mapping at
   [ffffc90000085000, ffffc90000087000) created by:
   cache_ctr+0x176a/0x35f0

  (...snip...)
  Memory state around the buggy address:
   ffffc90000084f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
   ffffc90000084f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
  >ffffc90000085000: 00 00 00 00 00 00 00 00 f8 f8 f8 f8 f8 f8 f8 f8
                                             ^
   ffffc90000085080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
   ffffc90000085100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8

Fix by checking the size change on the first resume.

Signed-off-by: Ming-Hung Tsai 
Fixes: f494a9c6b1b6 ("dm cache: cache shrinking support")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Acked-by: Joe Thornber 
Signed-off-by: Greg Kroah-Hartman

dm cache: optimize dirty bit checking with find_next_bit when resizing

2024-11-17T13:58:51+00:00

commit f484697e619a83ecc370443a34746379ad99d204 upstream.

When shrinking the fast device, dm-cache iteratively searches for a
dirty bit among the cache blocks to be dropped, which is less efficient.
Use find_next_bit instead, as it is twice as fast as the iterative
approach with test_bit.

Signed-off-by: Ming-Hung Tsai 
Fixes: f494a9c6b1b6 ("dm cache: cache shrinking support")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Acked-by: Joe Thornber 
Signed-off-by: Greg Kroah-Hartman

dm cache: fix out-of-bounds access to the dirty bitset when resizing

2024-11-17T13:58:51+00:00

commit 792227719725497ce10a8039803bec13f89f8910 upstream.

dm-cache checks the dirty bits of the cache blocks to be dropped when
shrinking the fast device, but an index bug in bitset iteration causes
out-of-bounds access.

Reproduce steps:

1. create a cache device of 1024 cache blocks (128 bytes dirty bitset)

dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 131072 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc 262144"
dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct
dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"

2. shrink the fast device to 512 cache blocks, triggering out-of-bounds
   access to the dirty bitset (offset 0x80)

dmsetup suspend cache
dmsetup reload cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup resume cdata
dmsetup resume cache

KASAN reports:

  BUG: KASAN: vmalloc-out-of-bounds in cache_preresume+0x269/0x7b0
  Read of size 8 at addr ffffc900000f3080 by task dmsetup/131

  (...snip...)
  The buggy address belongs to the virtual mapping at
   [ffffc900000f3000, ffffc900000f5000) created by:
   cache_ctr+0x176a/0x35f0

  (...snip...)
  Memory state around the buggy address:
   ffffc900000f2f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
   ffffc900000f3000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  >ffffc900000f3080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                     ^
   ffffc900000f3100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
   ffffc900000f3180: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8

Fix by making the index post-incremented.

Signed-off-by: Ming-Hung Tsai 
Fixes: f494a9c6b1b6 ("dm cache: cache shrinking support")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Acked-by: Joe Thornber 
Signed-off-by: Greg Kroah-Hartman

dm cache: correct the number of origin blocks to match the target length

2024-11-17T13:58:51+00:00

commit 235d2e739fcbe964c9ce179b4c991025662dcdb6 upstream.

When creating a cache device, the actual size of the cache origin might
be greater than the specified cache target length. In such case, the
number of origin blocks should match the cache target length, not the
full size of the origin device, since access beyond the cache target is
not possible. This issue occurs when reducing the origin device size
using lvm, as lvreduce preloads the new cache table before resuming the
cache origin, which can result in incorrect sizes for the discard bitset
and smq hotspot blocks.

Reproduce steps:

1. create a cache device consists of 4096 origin blocks

dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc 262144"
dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct
dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"

2. reduce the cache origin to 2048 oblocks, in lvreduce's approach

dmsetup reload corig --table "0 262144 linear /dev/sdc 262144"
dmsetup reload cache --table "0 262144 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"
dmsetup suspend cache
dmsetup suspend corig
dmsetup suspend cdata
dmsetup suspend cmeta
dmsetup resume corig
dmsetup resume cdata
dmsetup resume cmeta
dmsetup resume cache

3. shutdown the cache, and check the number of discard blocks in
   superblock. The value is expected to be 2048, but actually is 4096.

dmsetup remove cache corig cdata cmeta
dd if=/dev/sdc bs=1c count=8 skip=224 2>/dev/null | hexdump -e '1/8 "%u\n"'

Fix by correcting the origin_blocks initialization in cache_create and
removing the unused origin_sectors from struct cache_args accordingly.

Signed-off-by: Ming-Hung Tsai 
Fixes: c6b4fcbad044 ("dm: add cache target")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Acked-by: Joe Thornber 
Signed-off-by: Greg Kroah-Hartman

dm init: Handle minors larger than 255

2024-09-12T09:03:53+00:00

[ Upstream commit 140ce37fd78a629105377e17842465258a5459ef ]

dm_parse_device_entry() simply copies the minor number into dmi.dev, but
the dev_t format splits the minor number between the lowest 8 bytes and
highest 12 bytes. If the minor number is larger than 255, part of it
will end up getting treated as the major number

Fix this by checking that the minor number is valid and then encoding it
as a dev_t.

Signed-off-by: Benjamin Marzinski 
Signed-off-by: Mikulas Patocka 
Signed-off-by: Sasha Levin

dm suspend: return -ERESTARTSYS instead of -EINTR

2024-09-04T11:14:58+00:00

[ Upstream commit 1e1fd567d32fcf7544c6e09e0e5bc6c650da6e23 ]

This commit changes device mapper, so that it returns -ERESTARTSYS
instead of -EINTR when it is interrupted by a signal (so that the ioctl
can be restarted).

The manpage signal(7) says that the ioctl function should be restarted if
the signal was handled with SA_RESTART.

Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin

dm: do not use waitqueue for request-based DM

2024-09-04T11:14:58+00:00

[ Upstream commit 85067747cf9888249fa11fa49ef75af5192d3988 ]

Given request-based DM now uses blk-mq's blk_mq_queue_inflight() to
determine if outstanding IO has completed (and DM has no control over
the blk-mq state machine used to track outstanding IO) it is unsafe to
wakeup waiter (dm_wait_for_completion) before blk-mq has cleared a
request's state bits (e.g. MQ_RQ_IN_FLIGHT or MQ_RQ_COMPLETE).  As
such dm_wait_for_completion() could be left to wait indefinitely if no
other requests complete.

Fix this by eliminating request-based DM's use of waitqueue to wait
for blk-mq requests to complete in dm_wait_for_completion.

Signed-off-by: Ming Lei 
Depends-on: 3c94d83cb3526 ("blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer 
Stable-dep-of: 1e1fd567d32f ("dm suspend: return -ERESTARTSYS instead of -EINTR")
Signed-off-by: Sasha Levin

dm mpath: pass IO start time to path selector

2024-09-04T11:14:58+00:00

[ Upstream commit 087615bf3acdafd0ba7c7c9ed5286e7b7c80fe1b ]

The HST path selector needs this information to perform path
prediction. For request-based mpath, struct request's io_start_time_ns
is used, while for bio-based, use the start_time stored in dm_io.

Signed-off-by: Gabriel Krisman Bertazi 
Signed-off-by: Mike Snitzer 
Stable-dep-of: 1e1fd567d32f ("dm suspend: return -ERESTARTSYS instead of -EINTR")
Signed-off-by: Sasha Levin