linux-stable.git/drivers/md, branch v4.14.313

md: avoid signed overflow in slot_store()

2023-04-05T09:14:19+00:00

[ Upstream commit 3bc57292278a0b6ac4656cad94c14f2453344b57 ]

slot_store() uses kstrtouint() to get a slot number, but stores the
result in an "int" variable (by casting a pointer).
This can result in a negative slot number if the unsigned int value is
very large.

A negative number means that the slot is empty, but setting a negative
slot number this way will not remove the device from the array.  I don't
think this is a serious problem, but it could cause confusion and it is
best to fix it.

Reported-by: Dan Carpenter 
Signed-off-by: NeilBrown 
Signed-off-by: Song Liu 
Signed-off-by: Sasha Levin

dm crypt: add cond_resched() to dmcrypt_write()

2023-04-05T09:14:18+00:00

commit fb294b1c0ba982144ca467a75e7d01ff26304e2b upstream.

The loop in dmcrypt_write may be running for unbounded amount of time,
thus we need cond_resched() in it.

This commit fixes the following warning:

[ 3391.153255][   C12] watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [dmcrypt_write/2:2897]
...
[ 3391.387210][   C12] Call trace:
[ 3391.390338][   C12]  blk_attempt_bio_merge.part.6+0x38/0x158
[ 3391.395970][   C12]  blk_attempt_plug_merge+0xc0/0x1b0
[ 3391.401085][   C12]  blk_mq_submit_bio+0x398/0x550
[ 3391.405856][   C12]  submit_bio_noacct+0x308/0x380
[ 3391.410630][   C12]  dmcrypt_write+0x1e4/0x208 [dm_crypt]
[ 3391.416005][   C12]  kthread+0x130/0x138
[ 3391.419911][   C12]  ret_from_fork+0x10/0x18

Reported-by: yangerkun 
Fixes: dc2676210c42 ("dm crypt: offload writes to thread")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm stats: check for and propagate alloc_percpu failure

2023-04-05T09:14:18+00:00

commit d3aa3e060c4a80827eb801fc448debc9daa7c46b upstream.

Check alloc_precpu()'s return value and return an error from
dm_stats_init() if it fails. Update alloc_dev() to fail if
dm_stats_init() does.

Otherwise, a NULL pointer dereference will occur in dm_stats_cleanup()
even if dm-stats isn't being actively used.

Fixes: fd2ed4d25270 ("dm: add statistics support")
Cc: stable@vger.kernel.org
Signed-off-by: Jiasheng Jiang 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm flakey: don't corrupt the zero page

2023-03-11T15:26:47+00:00

commit f50714b57aecb6b3dc81d578e295f86d9c73f078 upstream.

When we need to zero some range on a block device, the function
__blkdev_issue_zero_pages submits a write bio with the bio vector pointing
to the zero page. If we use dm-flakey with corrupt bio writes option, it
will corrupt the content of the zero page which results in crashes of
various userspace programs. Glibc assumes that memory returned by mmap is
zeroed and it uses it for calloc implementation; if the newly mapped
memory is not zeroed, calloc will return non-zeroed memory.

Fix this bug by testing if the page is equal to ZERO_PAGE(0) and
avoiding the corruption in this case.

Cc: stable@vger.kernel.org
Fixes: a00f5276e266 ("dm flakey: Properly corrupt multi-page bios.")
Signed-off-by: Mikulas Patocka 
Reviewed-by: Sweet Tea Dorminy 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm flakey: fix logic when corrupting a bio

2023-03-11T15:26:47+00:00

commit aa56b9b75996ff4c76a0a4181c2fa0206c3d91cc upstream.

If "corrupt_bio_byte" is set to corrupt reads and corrupt_bio_flags is
used, dm-flakey would erroneously return all writes as errors. Likewise,
if "corrupt_bio_byte" is set to corrupt writes, dm-flakey would return
errors for all reads.

Fix the logic so that if fc->corrupt_bio_byte is non-zero, dm-flakey
will not abort reads on writes with an error.

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

dm cache: add cond_resched() to various workqueue loops

2023-03-11T15:26:43+00:00

[ Upstream commit 76227f6dc805e9e960128bcc6276647361e0827c ]

Otherwise on resource constrained systems these workqueues may be too
greedy.

Signed-off-by: Mike Snitzer 
Signed-off-by: Sasha Levin

dm thin: add cond_resched() to various workqueue loops

2023-03-11T15:26:43+00:00

[ Upstream commit e4f80303c2353952e6e980b23914e4214487f2a6 ]

Otherwise on resource constrained systems these workqueues may be too
greedy.

Signed-off-by: Mike Snitzer 
Signed-off-by: Sasha Levin

dm: remove flush_scheduled_work() during local_exit()

2023-03-11T15:26:39+00:00

[ Upstream commit 0b22ff5360f5c4e11050b89206370fdf7dc0a226 ]

Commit acfe0ad74d2e1 ("dm: allocate a special workqueue for deferred
device removal") switched from using system workqueue to a single
workqueue local to DM.  But it didn't eliminate the call to
flush_scheduled_work() that was introduced purely for the benefit of
deferred device removal with commit 2c140a246dc ("dm: allow remove to
be deferred").

Since DM core uses its own workqueue (and queue_work) there is no need
to call flush_scheduled_work() from local_exit().  local_exit()'s
destroy_workqueue(deferred_remove_workqueue) handles flushing work
started with queue_work().

Fixes: acfe0ad74d2e1 ("dm: allocate a special workqueue for deferred device removal")
Signed-off-by: Mike Snitzer 
Signed-off-by: Sasha Levin

dm cache: set needs_check flag after aborting metadata

2023-01-18T08:26:37+00:00

commit 6b9973861cb2e96dcd0bb0f1baddc5c034207c5c upstream.

Otherwise the commit that will be aborted will be associated with the
metadata objects that will be torn down.  Must write needs_check flag
to metadata with a reset block manager.

Found through code-inspection (and compared against dm-thin.c).

Cc: stable@vger.kernel.org
Fixes: 028ae9f76f29 ("dm cache: add fail io mode and needs_check flag")
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm cache: Fix UAF in destroy()

2023-01-18T08:26:37+00:00

commit 6a459d8edbdbe7b24db42a5a9f21e6aa9e00c2aa upstream.

Dm_cache also has the same UAF problem when dm_resume()
and dm_destroy() are concurrent.

Therefore, cancelling timer again in destroy().

Cc: stable@vger.kernel.org
Fixes: c6b4fcbad044e ("dm: add cache target")
Signed-off-by: Luo Meng 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman