linux-stable.git/drivers/md/raid10.c, branch linux-6.3.y

md/raid1-10: factor out a helper to submit normal write

2023-07-11T17:39:22+00:00

[ Upstream commit 8295efbe68c080047e98d9c0eb5cb933b238a8cb ]

There are multiple places to do the same thing, factor out a helper to
prevent redundant code, and the helper will be used in following patch
as well.

Signed-off-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230529131106.2123367-4-yukuai1@huaweicloud.com
Stable-dep-of: 7db922bae3ab ("md/raid1-10: submit write io directly if bitmap is not enabled")
Signed-off-by: Sasha Levin

md/raid1-10: factor out a helper to add bio to plug

2023-07-11T17:39:22+00:00

[ Upstream commit 5ec6ca140a034682e421e2e808ef5ddfdfd65242 ]

The code in raid1 and raid10 is identical, prepare to limit the number
of plugged bios.

Signed-off-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230529131106.2123367-3-yukuai1@huaweicloud.com
Stable-dep-of: 7db922bae3ab ("md/raid1-10: submit write io directly if bitmap is not enabled")
Signed-off-by: Sasha Levin

md/raid10: fix io loss while replacement replace rdev

2023-07-11T17:39:22+00:00

[ Upstream commit 2ae6aaf76912bae53c74b191569d2ab484f24bf3 ]

When removing a disk with replacement, the replacement will be used to
replace rdev. During this process, there is a brief window in which both
rdev and replacement are read as NULL in raid10_write_request(). This
will result in io not being submitted but it should be.

  //remove				//write
  raid10_remove_disk			raid10_write_request
   mirror->rdev = NULL
					 read rdev -> NULL
   mirror->rdev = mirror->replacement
   mirror->replacement = NULL
					 read replacement -> NULL

Fix it by reading replacement first and rdev later, meanwhile, use smp_mb()
to prevent memory reordering.

Fixes: 475b0321a4df ("md/raid10: writes should get directed to replacement as well as original.")
Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230602091839.743798-3-linan666@huaweicloud.com
Signed-off-by: Sasha Levin

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

2023-07-11T17:39:22+00:00

[ Upstream commit 34817a2441747b48e444cb0e05d84e14bc9443da ]

There are two check of 'mreplace' in raid10_sync_request(). In the first
check, 'need_replace' will be set and 'mreplace' will be used later if
no-Faulty 'mreplace' exists, In the second check, 'mreplace' will be
set to NULL if it is Faulty, but 'need_replace' will not be changed
accordingly. null-ptr-deref occurs if Faulty is set between two check.

Fix it by merging two checks into one. And replace 'need_replace' with
'mreplace' because their values are always the same.

Fixes: ee37d7314a32 ("md/raid10: Fix raid10 replace hang when new added disk faulty")
Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230527072218.2365857-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin

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

2023-05-11T14:17:18+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

2023-05-11T14:17:18+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

md/raid10: fix memleak for 'conf->bio_split'

2023-05-11T14:17:18+00:00

[ Upstream commit c9ac2acde53f5385de185bccf6aaa91cf9ac1541 ]

In the error path of raid10_run(), 'conf' need be freed, however,
'conf->bio_split' is missed and memory will be leaked.

Since there are 3 places to free 'conf', factor out a helper to fix the
problem.

Fixes: fc9977dd069e ("md/raid10: simplify the splitting of requests.")
Signed-off-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230310073855.1337560-6-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin

md/raid10: fix leak of 'r10bio->remaining' for recovery

2023-05-11T14:17:18+00:00

[ Upstream commit 26208a7cffd0c7cbf14237ccd20c7270b3ffeb7e ]

raid10_sync_request() will add 'r10bio->remaining' for both rdev and
replacement rdev. However, if the read io fails, recovery_request_write()
returns without issuing the write io, in this case, end_sync_request()
is only called once and 'remaining' is leaked, cause an io hang.

Fix the problem by decreasing 'remaining' according to if 'bio' and
'repl_bio' is valid.

Fixes: 24afd80d99f8 ("md/raid10: handle recovery of replacement devices.")
Signed-off-by: Yu Kuai 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230310073855.1337560-5-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin

md/raid10: fix task hung in raid10d

2023-05-11T14:17:18+00:00

[ Upstream commit 72c215ed8731c88b2d7e09afc51fffc207ae47b8 ]

commit fe630de009d0 ("md/raid10: avoid deadlock on recovery.") allowed
normal io and sync io to exist at the same time. Task hung will occur as
below:

T1                      T2		T3		T4
raid10d
 handle_read_error
  allow_barrier
   conf->nr_pending--
    -> 0
                        //submit sync io
                        raid10_sync_request
                         raise_barrier
			  ->will not be blocked
			  ...
			//submit to drivers
  raid10_read_request
   wait_barrier
    conf->nr_pending++
     -> 1
					//retry read fail
					raid10_end_read_request
					 reschedule_retry
					  add to retry_list
					  conf->nr_queued++
					   -> 1
							//sync io fail
							end_sync_read
							 __end_sync_read
							  reschedule_retry
							   add to retry_list
					                    conf->nr_queued++
							     -> 2
 ...
 handle_read_error
 get form retry_list
 conf->nr_queued--
  freeze_array
   wait nr_pending == nr_queued+1
        ->1	      ->2
   //task hung

retry read and sync io will be added to retry_list(nr_queued->2) if they
fails. raid10d() called handle_read_error() and hung in freeze_array().
nr_queued will not decrease because raid10d is blocked, nr_pending will
not increase because conf->barrier is not released.

Fix it by moving allow_barrier() after raid10_read_request().
raise_barrier() will wait for nr_waiting to become 0. Therefore, sync io
and regular io will not be issued at the same time.

Also remove the check of nr_queued in stop_waiting_barrier. It can be 0
but don't need to be blocking. Remove the check for MD_RECOVERY_RUNNING as
the check is redundent.

Fixes: fe630de009d0 ("md/raid10: avoid deadlock on recovery.")
Signed-off-by: Li Nan 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20230222041000.3341651-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin

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

2023-05-11T14:16:55+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