6217 Commits

Author SHA1 Message Date
Nigel Croxon
a8403f9fd4 md/raid1: fix error: ISO C90 forbids mixed declarations
[ Upstream commit df203da47f4428bc286fc99318936416253a321c ]

There is a compile error when this commit is added:
md: raid1: fix potential OOB in raid1_remove_disk()

drivers/md/raid1.c: In function 'raid1_remove_disk':
drivers/md/raid1.c:1844:9: error: ISO C90 forbids mixed declarations
and code [-Werror=declaration-after-statement]
1844 |         struct raid1_info *p = conf->mirrors + number;
     |         ^~~~~~

That's because the new code was inserted before the struct.
The change is move the struct command above this commit.

Fixes: 8b0472b50bcf ("md: raid1: fix potential OOB in raid1_remove_disk()")
Signed-off-by: Nigel Croxon <ncroxon@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/46d929d0-2aab-4cf2-b2bf-338963e8ba5a@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 11:00:06 +02:00
Zhang Shurong
25a68f2286 md: raid1: fix potential OOB in raid1_remove_disk()
[ Upstream commit 8b0472b50bcf0f19a5119b00a53b63579c8e1e4d ]

If rddev->raid_disk is greater than mddev->raid_disks, there will be
an out-of-bounds in raid1_remove_disk(). We have already found
similar reports as follows:

1) commit d17f744e883b ("md-raid10: fix KASAN warning")
2) commit 1ebc2cec0b7d ("dm raid: fix KASAN warning in raid5_remove_disk")

Fix this bug by checking whether the "number" variable is
valid.

Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/tencent_0D24426FAC6A21B69AC0C03CE4143A508F09@qq.com
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 11:00:04 +02:00
Yu Kuai
1603f08620 md/md-bitmap: hold 'reconfig_mutex' in backlog_store()
[ Upstream commit 44abfa6a95df425c0660d56043020b67e6d93ab8 ]

Several reasons why 'reconfig_mutex' should be held:

1) rdev_for_each() is not safe to be called without the lock, because
   rdev can be removed concurrently.
2) mddev_destroy_serial_pool() and mddev_create_serial_pool() should not
   be called concurrently.
3) mddev_suspend() from mddev_destroy/create_serial_pool() should be
   protected by the lock.

Fixes: 10c92fca636e ("md-bitmap: create and destroy wb_info_pool with the change of backlog")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230706083727.608914-3-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 10:59:45 +02:00
Guoqing Jiang
630be0110e md/bitmap: don't set max_write_behind if there is no write mostly device
[ Upstream commit 8c13ab115b577bd09097b9d77916732e97e31b7b ]

We shouldn't set it since write behind IO should only happen to write
mostly device.

Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
Stable-dep-of: 44abfa6a95df ("md/md-bitmap: hold 'reconfig_mutex' in backlog_store()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 10:59:45 +02:00
Mikulas Patocka
d0ef103e19 dm integrity: reduce vmalloc space footprint on 32-bit architectures
[ Upstream commit 6d50eb4725934fd22f5eeccb401000687c790fd0 ]

It was reported that dm-integrity runs out of vmalloc space on 32-bit
architectures. On x86, there is only 128MiB vmalloc space and dm-integrity
consumes it quickly because it has a 64MiB journal and 8MiB recalculate
buffer.

Fix this by reducing the size of the journal to 4MiB and the size of
the recalculate buffer to 1MiB, so that multiple dm-integrity devices
can be created and activated on 32-bit architectures.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-30 16:27:22 +02:00
Mikulas Patocka
072d247d7a dm integrity: increase RECALC_SECTORS to improve recalculate speed
[ Upstream commit b1a2b9332050c7ae32a22c2c74bc443e39f37b23 ]

Increase RECALC_SECTORS because it improves recalculate speed slightly
(from 390kiB/s to 410kiB/s).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Stable-dep-of: 6d50eb472593 ("dm integrity: reduce vmalloc space footprint on 32-bit architectures")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-30 16:27:21 +02:00
Joe Thornber
81cd6ceee7 dm cache policy smq: ensure IO doesn't prevent cleaner policy progress
commit 1e4ab7b4c881cf26c1c72b3f56519e03475486fb upstream.

When using the cleaner policy to decommission the cache, there is
never any writeback started from the cache as it is constantly delayed
due to normal I/O keeping the device busy. Meaning @idle=false was
always being passed to clean_target_met()

Fix this by adding a specific 'cleaner' flag that is set when the
cleaner policy is configured. This flag serves to always allow the
cleaner's writeback work to be queued until the cache is
decommissioned (even if the cache isn't idle).

Reported-by: David Jeffery <djeffery@redhat.com>
Fixes: b29d4986d0da ("dm cache: significant rework to leverage dm-bio-prison-v2")
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 11:53:53 +02:00
Yu Kuai
53c06e0d15 dm raid: fix missing reconfig_mutex unlock in raid_ctr() error paths
[ Upstream commit bae3028799dc4f1109acc4df37c8ff06f2d8f1a0 ]

In the error paths 'bad_stripe_cache' and 'bad_check_reshape',
'reconfig_mutex' is still held after raid_ctr() returns.

Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11 11:53:49 +02:00
Zheng Wang
b070f29a61 bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent
[ Upstream commit 80fca8a10b604afad6c14213fdfd816c4eda3ee4 ]

In some specific situations, the return value of __bch_btree_node_alloc
may be NULL. This may lead to a potential NULL pointer dereference in
caller function like a calling chain :
btree_split->bch_btree_node_alloc->__bch_btree_node_alloc.

Fix it by initializing the return value in __bch_btree_node_alloc.

Fixes: cafe56359144 ("bcache: A block layer cache")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20230615121223.22502-6-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11 11:53:44 +02:00
Coly Li
38a6dd2b68 bcache: remove 'int n' from parameter list of bch_bucket_alloc_set()
[ Upstream commit 17e4aed8309ff28670271546c2c3263eb12f5eb6 ]

The parameter 'int n' from bch_bucket_alloc_set() is not cleared
defined. From the code comments n is the number of buckets to alloc, but
from the code itself 'n' is the maximum cache to iterate. Indeed all the
locations where bch_bucket_alloc_set() is called, 'n' is alwasy 1.

This patch removes the confused and unnecessary 'int n' from parameter
list of  bch_bucket_alloc_set(), and explicitly allocates only 1 bucket
for its caller.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 80fca8a10b60 ("bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11 11:53:44 +02:00
Yu Kuai
d0345f7c7d md/raid10: prevent soft lockup while flush writes
[ Upstream commit 010444623e7f4da6b4a4dd603a7da7469981e293 ]

Currently, there is no limit for raid1/raid10 plugged bio. While flushing
writes, raid1 has cond_resched() while raid10 doesn't, and too many
writes can cause soft lockup.

Follow up soft lockup can be triggered easily with writeback test for
raid10 with ramdisks:

watchdog: BUG: soft lockup - CPU#10 stuck for 27s! [md0_raid10:1293]
Call Trace:
 <TASK>
 call_rcu+0x16/0x20
 put_object+0x41/0x80
 __delete_object+0x50/0x90
 delete_object_full+0x2b/0x40
 kmemleak_free+0x46/0xa0
 slab_free_freelist_hook.constprop.0+0xed/0x1a0
 kmem_cache_free+0xfd/0x300
 mempool_free_slab+0x1f/0x30
 mempool_free+0x3a/0x100
 bio_free+0x59/0x80
 bio_put+0xcf/0x2c0
 free_r10bio+0xbf/0xf0
 raid_end_bio_io+0x78/0xb0
 one_write_done+0x8a/0xa0
 raid10_end_write_request+0x1b4/0x430
 bio_endio+0x175/0x320
 brd_submit_bio+0x3b9/0x9b7 [brd]
 __submit_bio+0x69/0xe0
 submit_bio_noacct_nocheck+0x1e6/0x5a0
 submit_bio_noacct+0x38c/0x7e0
 flush_pending_writes+0xf0/0x240
 raid10d+0xac/0x1ed0

Fix the problem by adding cond_resched() to raid10 like what raid1 did.

Note that unlimited plugged bio still need to be optimized, for example,
in the case of lots of dirty pages writeback, this will take lots of
memory and io will spend a long time in plug, hence io latency is bad.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230529131106.2123367-2-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:41 +02:00
Yu Kuai
09539f9e20 md: fix data corruption for raid456 when reshape restart while grow up
[ Upstream commit 873f50ece41aad5c4f788a340960c53774b5526e ]

Currently, if reshape is interrupted, echo "reshape" to sync_action will
restart reshape from scratch, for example:

echo frozen > sync_action
echo reshape > sync_action

This will corrupt data before reshape_position if the array is growing,
fix the problem by continue reshape from reshape_position.

Reported-by: Peter Neuwirth <reddunur@online.de>
Link: https://lore.kernel.org/linux-raid/e2f96772-bfbc-f43b-6da1-f520e5164536@online.de/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230512015610.821290-3-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:41 +02:00
Jason Baron
ecfd1f82c4 md/raid0: add discard support for the 'original' layout
commit e836007089ba8fdf24e636ef2b007651fb4582e6 upstream.

We've found that using raid0 with the 'original' layout and discard
enabled with different disk sizes (such that at least two zones are
created) can result in data corruption. This is due to the fact that
the discard handling in 'raid0_handle_discard()' assumes the 'alternate'
layout. We've seen this corruption using ext4 but other filesystems are
likely susceptible as well.

More specifically, while multiple zones are necessary to create the
corruption, the corruption may not occur with multiple zones if they
layout in such a way the layout matches what the 'alternate' layout
would have produced. Thus, not all raid0 devices with the 'original'
layout, different size disks and discard enabled will encounter this
corruption.

The 3.14 kernel inadvertently changed the raid0 disk layout for different
size disks. Thus, running a pre-3.14 kernel and post-3.14 kernel on the
same raid0 array could corrupt data. This lead to the creation of the
'original' layout (to match the pre-3.14 layout) and the 'alternate' layout
(to match the post 3.14 layout) in the 5.4 kernel time frame and an option
to tell the kernel which layout to use (since it couldn't be autodetected).
However, when the 'original' layout was added back to 5.4 discard support
for the 'original' layout was not added leading this issue.

I've been able to reliably reproduce the corruption with the following
test case:

1. create raid0 array with different size disks using original layout
2. mkfs
3. mount -o discard
4. create lots of files
5. remove 1/2 the files
6. fstrim -a (or just the mount point for the raid0 array)
7. umount
8. fsck -fn /dev/md0 (spews all sorts of corruptions)

Let's fix this by adding proper discard support to the 'original' layout.
The fix 'maps' the 'original' layout disks to the order in which they are
read/written such that we can compare the disks in the same way that the
current 'alternate' layout does. A 'disk_shift' field is added to
'struct strip_zone'. This could be computed on the fly in
raid0_handle_discard() but by adding this field, we save some computation
in the discard path.

Note we could also potentially fix this by re-ordering the disks in the
zones that follow the first one, and then always read/writing them using
the 'alternate' layout. However, that is seen as a more substantial change,
and we are attempting the least invasive fix at this time to remedy the
corruption.

I've verified the change using the reproducer mentioned above. Typically,
the corruption is seen after less than 3 iterations, while the patch has
run 500+ iterations.

Cc: NeilBrown <neilb@suse.de>
Cc: Song Liu <song@kernel.org>
Fixes: c84a1372df92 ("md/raid0: avoid RAID0 data corruption due to layout confusion.")
Cc: stable@vger.kernel.org
Signed-off-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230623180523.1901230-1-jbaron@akamai.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:37:37 +02:00
Zheng Wang
0729029e64 bcache: Remove unnecessary NULL point check in node allocations
commit 028ddcac477b691dd9205c92f991cc15259d033e upstream.

Due to the previous fix of __bch_btree_node_alloc, the return value will
never be a NULL pointer. So IS_ERR is enough to handle the failure
situation. Fix it by replacing IS_ERR_OR_NULL check by an IS_ERR check.

Fixes: cafe56359144 ("bcache: A block layer cache")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20230615121223.22502-5-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:37:25 +02:00
Li Nan
be48188175 md/raid10: fix io loss while replacement replace rdev
[ 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 <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230602091839.743798-3-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:05 +02:00
Li Nan
45fa023b33 md/raid10: fix null-ptr-deref of mreplace in raid10_sync_request
[ 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 <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230527072218.2365857-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:05 +02:00
Li Nan
31c805a44b md/raid10: fix wrong setting of max_corr_read_errors
[ Upstream commit f8b20a405428803bd9881881d8242c9d72c6b2b2 ]

There is no input check when echo md/max_read_errors and overflow might
occur. Add check of input number.

Fixes: 1e50915fe0bb ("raid: improve MD/raid10 handling of correctable read errors.")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230522072535.1523740-3-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:04 +02:00
Li Nan
283f4a63fe md/raid10: fix overflow of md/safe_mode_delay
[ Upstream commit 6beb489b2eed25978523f379a605073f99240c50 ]

There is no input check when echo md/safe_mode_delay in safe_delay_store().
And msec might also overflow when HZ < 1000 in safe_delay_show(), Fix it by
checking overflow in safe_delay_store() and use unsigned long conversion in
safe_delay_show().

Fixes: 72e02075a33f ("md: factor out parsing of fixed-point numbers")
Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230522072535.1523740-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:04 +02:00
Li Nan
b0b971fe7d md/raid10: check slab-out-of-bounds in md_bitmap_get_counter
[ Upstream commit 301867b1c16805aebbc306aafa6ecdc68b73c7e5 ]

If we write a large number to md/bitmap_set_bits, md_bitmap_checkpage()
will return -EINVAL because 'page >= bitmap->pages', but the return value
was not checked immediately in md_bitmap_get_counter() in order to set
*blocks value and slab-out-of-bounds occurs.

Move check of 'page >= bitmap->pages' to md_bitmap_get_counter() and
return directly if true.

Fixes: ef4256733506 ("md/bitmap: optimise scanning of empty bitmaps.")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230515134808.3936750-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:04 +02:00
Kees Cook
0638dcc7e7 treewide: Remove uninitialized_var() usage
commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-09 10:29:01 +02:00
Yeongjin Gil
439d3a7056 dm verity: fix error handling for check_at_most_once on FEC
[ Upstream commit e8c5d45f82ce0c238a4817739892fe8897a3dcc3 ]

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 <sj1557.seo@samsung.com>
Signed-off-by: Yeongjin Gil <youngjin.gil@samsung.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:57 +02:00
Akilesh Kailash
0156f7dbd8 dm verity: skip redundant verity_handle_err() on I/O errors
[ Upstream commit 2c0468e054c0adb660ac055fc396622ec7235df9 ]

Without FEC, dm-verity won't call verity_handle_err() when I/O fails,
but with FEC enabled, it currently does even if an I/O error has
occurred.

If there is an I/O error and FEC correction fails, return the error
instead of calling verity_handle_err() again.

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Akilesh Kailash <akailash@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Stable-dep-of: e8c5d45f82ce ("dm verity: fix error handling for check_at_most_once on FEC")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:57 +02:00
Mike Snitzer
29a1ef57c3 dm ioctl: fix nested locking in table_clear() to remove deadlock concern
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 <zheng.zhang@email.ucr.edu>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:35:56 +02:00
Mikulas Patocka
337b7af273 dm flakey: fix a crash with invalid table line
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 <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:35:56 +02:00
Mike Snitzer
6d126899b0 dm integrity: call kmem_cache_destroy() in dm_integrity_init() error path
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 <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:35:56 +02:00
Mike Snitzer
cbe0a7ec67 dm clone: call kmem_cache_destroy() in dm_clone_init() error path
commit 6827af4a9a9f5bb664c42abf7c11af4978d72201 upstream.

Otherwise the _hydration_cache will leak if dm_register_target() fails.

Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:35:56 +02:00
Li Nan
14964127be md/raid10: fix null-ptr-deref in raid10_sync_request
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 <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230222041000.3341651-3-linan666@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:35:55 +02:00
Yu Kuai
3725b35fc0 md/raid10: fix memleak of md thread
[ 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 <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230310073855.1337560-7-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:44 +02:00
Christoph Hellwig
fb3f2f2fa0 md: update the optimal I/O size on reshape
[ Upstream commit 16ef510139315a2147ee7525796f8dbd4e4b7864 ]

The raid5 and raid10 drivers currently update the read-ahead size,
but not the optimal I/O size on reshape.  To prepare for deriving the
read-ahead size from the optimal I/O size make sure it is updated
as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: f0ddb83da3cb ("md/raid10: fix memleak of md thread")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:44 +02:00
Yu Kuai
b6460f68c1 md/raid10: fix memleak for 'conf->bio_split'
[ 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 <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230310073855.1337560-6-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:43 +02:00
Yu Kuai
8c5d5d7ffd md/raid10: fix leak of 'r10bio->remaining' for recovery
[ 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 <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230310073855.1337560-5-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:43 +02:00
NeilBrown
88a3c63a96 md: avoid signed overflow in slot_store()
[ 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 <error27@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-05 11:16:42 +02:00
Mikulas Patocka
885c28ceae dm crypt: add cond_resched() to dmcrypt_write()
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 <yangerkun@huawei.com>
Fixes: dc2676210c42 ("dm crypt: offload writes to thread")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:16:41 +02:00
Jiasheng Jiang
4a32a9a818 dm stats: check for and propagate alloc_percpu failure
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 <jiasheng@iscas.ac.cn>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:16:41 +02:00
Coly Li
e9e93fdfce dm thin: fix deadlock when swapping to thin device
commit 9bbf5feecc7eab2c370496c1c161bbfe62084028 upstream.

This is an already known issue that dm-thin volume cannot be used as
swap, otherwise a deadlock may happen when dm-thin internal memory
demand triggers swap I/O on the dm-thin volume itself.

But thanks to commit a666e5c05e7c ("dm: fix deadlock when swapping to
encrypted device"), the limit_swap_bios target flag can also be used
for dm-thin to avoid the recursive I/O when it is used as swap.

Fix is to simply set ti->limit_swap_bios to true in both pool_ctr()
and thin_ctr().

In my test, I create a dm-thin volume /dev/vg/swap and use it as swap
device. Then I run fio on another dm-thin volume /dev/vg/main and use
large --blocksize to trigger swap I/O onto /dev/vg/swap.

The following fio command line is used in my test,
  fio --name recursive-swap-io --lockmem 1 --iodepth 128 \
     --ioengine libaio --filename /dev/vg/main --rw randrw \
    --blocksize 1M --numjobs 32 --time_based --runtime=12h

Without this fix, the whole system can be locked up within 15 seconds.

With this fix, there is no any deadlock or hung task observed after
2 hours of running fio.

Furthermore, if blocksize is changed from 1M to 128M, after around 30
seconds fio has no visible I/O, and the out-of-memory killer message
shows up in kernel message. After around 20 minutes all fio processes
are killed and the whole system is back to being alive.

This is exactly what is expected when recursive I/O happens on dm-thin
volume when it is used as swap.

Depends-on: a666e5c05e7c ("dm: fix deadlock when swapping to encrypted device")
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:16:40 +02:00
Mikulas Patocka
3c4a56ef7c dm flakey: don't corrupt the zero page
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 <mpatocka@redhat.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11 16:44:04 +01:00
Mikulas Patocka
a2be4225c3 dm flakey: fix logic when corrupting a bio
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 <mpatocka@redhat.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11 16:44:04 +01:00
Mike Snitzer
38b4d3eacb dm cache: add cond_resched() to various workqueue loops
[ Upstream commit 76227f6dc805e9e960128bcc6276647361e0827c ]

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

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:43:58 +01:00
Mike Snitzer
3b46b2cb91 dm thin: add cond_resched() to various workqueue loops
[ Upstream commit e4f80303c2353952e6e980b23914e4214487f2a6 ]

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

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:43:58 +01:00
Mike Snitzer
b89d2ed564 dm: remove flush_scheduled_work() during local_exit()
[ 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 <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:43:47 +01:00
Luo Meng
d06a7e2049 dm thin: resume even if in FAIL mode
[ Upstream commit 19eb1650afeb1aa86151f61900e9e5f1de5d8d02 ]

If a thinpool set fail_io while suspending, resume will fail with:
 device-mapper: resume ioctl on vg-thinpool  failed: Invalid argument

The thin-pool also can't be removed if an in-flight bio is in the
deferred list.

This can be easily reproduced using:

  echo "offline" > /sys/block/sda/device/state
  dd if=/dev/zero of=/dev/mapper/thin bs=4K count=1
  dmsetup suspend /dev/mapper/pool
  mkfs.ext4 /dev/mapper/thin
  dmsetup resume /dev/mapper/pool

The root cause is maybe_resize_data_dev() will check fail_io and return
error before called dm_resume.

Fix this by adding FAIL mode check at the end of pool_preresume().

Cc: stable@vger.kernel.org
Fixes: da105ed5fd7e ("dm thin metadata: introduce dm_pool_abort_metadata")
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:53 +01:00
Florian-Ewald Mueller
2c4832a089 md/bitmap: Fix bitmap chunk size overflow issues
commit 4555211190798b6b6fa2c37667d175bf67945c78 upstream.

- limit bitmap chunk size internal u64 variable to values not overflowing
  the u32 bitmap superblock structure variable stored on persistent media
- assign bitmap chunk size internal u64 variable from unsigned values to
  avoid possible sign extension artifacts when assigning from a s32 value

The bug has been there since at least kernel 4.0.
Steps to reproduce it:
1: mdadm -C /dev/mdx -l 1 --bitmap=internal --bitmap-chunk=256M -e 1.2
-n2 /dev/rnbd1 /dev/rnbd2
2 resize member device rnbd1 and rnbd2 to 8 TB
3 mdadm --grow /dev/mdx --size=max

The bitmap_chunksize will overflow without patch.

Cc: stable@vger.kernel.org

Signed-off-by: Florian-Ewald Mueller <florian-ewald.mueller@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:49 +01:00
Mike Snitzer
1a5165e80a dm cache: set needs_check flag after aborting metadata
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 <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Luo Meng
2f097dfac7 dm cache: Fix UAF in destroy()
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 <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Luo Meng
520b56cfd9 dm clone: Fix UAF in clone_dtr()
commit e4b5957c6f749a501c464f92792f1c8e26b61a94 upstream.

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

Therefore, cancelling timer again in clone_dtr().

Cc: stable@vger.kernel.org
Fixes: 7431b7835f554 ("dm: add clone target")
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Luo Meng
792e51aac3 dm integrity: Fix UAF in dm_integrity_dtr()
commit f50cb2cbabd6c4a60add93d72451728f86e4791c upstream.

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

Therefore, cancelling timer again in dm_integrity_dtr().

Cc: stable@vger.kernel.org
Fixes: 7eada909bfd7a ("dm: add integrity target")
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Luo Meng
7ae6aa6493 dm thin: Fix UAF in run_timer_softirq()
commit 88430ebcbc0ec637b710b947738839848c20feff upstream.

When dm_resume() and dm_destroy() are concurrent, it will
lead to UAF, as follows:

 BUG: KASAN: use-after-free in __run_timers+0x173/0x710
 Write of size 8 at addr ffff88816d9490f0 by task swapper/0/0
<snip>
 Call Trace:
  <IRQ>
  dump_stack_lvl+0x73/0x9f
  print_report.cold+0x132/0xaa2
  _raw_spin_lock_irqsave+0xcd/0x160
  __run_timers+0x173/0x710
  kasan_report+0xad/0x110
  __run_timers+0x173/0x710
  __asan_store8+0x9c/0x140
  __run_timers+0x173/0x710
  call_timer_fn+0x310/0x310
  pvclock_clocksource_read+0xfa/0x250
  kvm_clock_read+0x2c/0x70
  kvm_clock_get_cycles+0xd/0x20
  ktime_get+0x5c/0x110
  lapic_next_event+0x38/0x50
  clockevents_program_event+0xf1/0x1e0
  run_timer_softirq+0x49/0x90
  __do_softirq+0x16e/0x62c
  __irq_exit_rcu+0x1fa/0x270
  irq_exit_rcu+0x12/0x20
  sysvec_apic_timer_interrupt+0x8e/0xc0

One of the concurrency UAF can be shown as below:

        use                                  free
do_resume                           |
  __find_device_hash_cell           |
    dm_get                          |
      atomic_inc(&md->holders)      |
                                    | dm_destroy
                                    |   __dm_destroy
                                    |     if (!dm_suspended_md(md))
                                    |     atomic_read(&md->holders)
                                    |     msleep(1)
  dm_resume                         |
    __dm_resume                     |
      dm_table_resume_targets       |
        pool_resume                 |
          do_waker  #add delay work |
  dm_put                            |
    atomic_dec(&md->holders)        |
                                    |     dm_table_destroy
                                    |       pool_dtr
                                    |         __pool_dec
                                    |           __pool_destroy
                                    |             destroy_workqueue
                                    |             kfree(pool) # free pool
        time out
__do_softirq
  run_timer_softirq # pool has already been freed

This can be easily reproduced using:
  1. create thin-pool
  2. dmsetup suspend pool
  3. dmsetup resume pool
  4. dmsetup remove_all # Concurrent with 3

The root cause of this UAF bug is that dm_resume() adds timer after
dm_destroy() skips cancelling the timer because of suspend status.
After timeout, it will call run_timer_softirq(), however pool has
already been freed. The concurrency UAF bug will happen.

Therefore, cancelling timer again in __pool_destroy().

Cc: stable@vger.kernel.org
Fixes: 991d9fa02da0d ("dm: add thin provisioning target")
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Zhihao Cheng
f758987ff0 dm thin: Use last transaction's pmd->root when commit failed
commit 7991dbff6849f67e823b7cc0c15e5a90b0549b9f upstream.

Recently we found a softlock up problem in dm thin pool btree lookup
code due to corrupted metadata:

 Kernel panic - not syncing: softlockup: hung tasks
 CPU: 7 PID: 2669225 Comm: kworker/u16:3
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
 Workqueue: dm-thin do_worker [dm_thin_pool]
 Call Trace:
   <IRQ>
   dump_stack+0x9c/0xd3
   panic+0x35d/0x6b9
   watchdog_timer_fn.cold+0x16/0x25
   __run_hrtimer+0xa2/0x2d0
   </IRQ>
   RIP: 0010:__relink_lru+0x102/0x220 [dm_bufio]
   __bufio_new+0x11f/0x4f0 [dm_bufio]
   new_read+0xa3/0x1e0 [dm_bufio]
   dm_bm_read_lock+0x33/0xd0 [dm_persistent_data]
   ro_step+0x63/0x100 [dm_persistent_data]
   btree_lookup_raw.constprop.0+0x44/0x220 [dm_persistent_data]
   dm_btree_lookup+0x16f/0x210 [dm_persistent_data]
   dm_thin_find_block+0x12c/0x210 [dm_thin_pool]
   __process_bio_read_only+0xc5/0x400 [dm_thin_pool]
   process_thin_deferred_bios+0x1a4/0x4a0 [dm_thin_pool]
   process_one_work+0x3c5/0x730

Following process may generate a broken btree mixed with fresh and
stale btree nodes, which could get dm thin trapped in an infinite loop
while looking up data block:
 Transaction 1: pmd->root = A, A->B->C   // One path in btree
                pmd->root = X, X->Y->Z   // Copy-up
 Transaction 2: X,Z is updated on disk, Y write failed.
                // Commit failed, dm thin becomes read-only.
                process_bio_read_only
		 dm_thin_find_block
		  __find_block
		   dm_btree_lookup(pmd->root)
The pmd->root points to a broken btree, Y may contain stale node
pointing to any block, for example X, which gets dm thin trapped into
a dead loop while looking up Z.

Fix this by setting pmd->root in __open_metadata(), so that dm thin
will use the last transaction's pmd->root if commit failed.

Fetch a reproducer in [Link].

Linke: https://bugzilla.kernel.org/show_bug.cgi?id=216790
Cc: stable@vger.kernel.org
Fixes: 991d9fa02da0 ("dm: add thin provisioning target")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Zhihao Cheng
200aa33b5d dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata
commit 8111964f1b8524c4bb56b02cd9c7a37725ea21fd upstream.

Following concurrent processes:

          P1(drop cache)                P2(kworker)
drop_caches_sysctl_handler
 drop_slab
  shrink_slab
   down_read(&shrinker_rwsem)  - LOCK A
   do_shrink_slab
    super_cache_scan
     prune_icache_sb
      dispose_list
       evict
        ext4_evict_inode
	 ext4_clear_inode
	  ext4_discard_preallocations
	   ext4_mb_load_buddy_gfp
	    ext4_mb_init_cache
	     ext4_read_block_bitmap_nowait
	      ext4_read_bh_nowait
	       submit_bh
	        dm_submit_bio
		                 do_worker
				  process_deferred_bios
				   commit
				    metadata_operation_failed
				     dm_pool_abort_metadata
				      down_write(&pmd->root_lock) - LOCK B
		                      __destroy_persistent_data_objects
				       dm_block_manager_destroy
				        dm_bufio_client_destroy
				         unregister_shrinker
					  down_write(&shrinker_rwsem)
		 thin_map                            |
		  dm_thin_find_block                 ↓
		   down_read(&pmd->root_lock) --> ABBA deadlock

, which triggers hung task:

[   76.974820] INFO: task kworker/u4:3:63 blocked for more than 15 seconds.
[   76.976019]       Not tainted 6.1.0-rc4-00011-g8f17dd350364-dirty #910
[   76.978521] task:kworker/u4:3    state:D stack:0     pid:63    ppid:2
[   76.978534] Workqueue: dm-thin do_worker
[   76.978552] Call Trace:
[   76.978564]  __schedule+0x6ba/0x10f0
[   76.978582]  schedule+0x9d/0x1e0
[   76.978588]  rwsem_down_write_slowpath+0x587/0xdf0
[   76.978600]  down_write+0xec/0x110
[   76.978607]  unregister_shrinker+0x2c/0xf0
[   76.978616]  dm_bufio_client_destroy+0x116/0x3d0
[   76.978625]  dm_block_manager_destroy+0x19/0x40
[   76.978629]  __destroy_persistent_data_objects+0x5e/0x70
[   76.978636]  dm_pool_abort_metadata+0x8e/0x100
[   76.978643]  metadata_operation_failed+0x86/0x110
[   76.978649]  commit+0x6a/0x230
[   76.978655]  do_worker+0xc6e/0xd90
[   76.978702]  process_one_work+0x269/0x630
[   76.978714]  worker_thread+0x266/0x630
[   76.978730]  kthread+0x151/0x1b0
[   76.978772] INFO: task test.sh:2646 blocked for more than 15 seconds.
[   76.979756]       Not tainted 6.1.0-rc4-00011-g8f17dd350364-dirty #910
[   76.982111] task:test.sh         state:D stack:0     pid:2646  ppid:2459
[   76.982128] Call Trace:
[   76.982139]  __schedule+0x6ba/0x10f0
[   76.982155]  schedule+0x9d/0x1e0
[   76.982159]  rwsem_down_read_slowpath+0x4f4/0x910
[   76.982173]  down_read+0x84/0x170
[   76.982177]  dm_thin_find_block+0x4c/0xd0
[   76.982183]  thin_map+0x201/0x3d0
[   76.982188]  __map_bio+0x5b/0x350
[   76.982195]  dm_submit_bio+0x2b6/0x930
[   76.982202]  __submit_bio+0x123/0x2d0
[   76.982209]  submit_bio_noacct_nocheck+0x101/0x3e0
[   76.982222]  submit_bio_noacct+0x389/0x770
[   76.982227]  submit_bio+0x50/0xc0
[   76.982232]  submit_bh_wbc+0x15e/0x230
[   76.982238]  submit_bh+0x14/0x20
[   76.982241]  ext4_read_bh_nowait+0xc5/0x130
[   76.982247]  ext4_read_block_bitmap_nowait+0x340/0xc60
[   76.982254]  ext4_mb_init_cache+0x1ce/0xdc0
[   76.982259]  ext4_mb_load_buddy_gfp+0x987/0xfa0
[   76.982263]  ext4_discard_preallocations+0x45d/0x830
[   76.982274]  ext4_clear_inode+0x48/0xf0
[   76.982280]  ext4_evict_inode+0xcf/0xc70
[   76.982285]  evict+0x119/0x2b0
[   76.982290]  dispose_list+0x43/0xa0
[   76.982294]  prune_icache_sb+0x64/0x90
[   76.982298]  super_cache_scan+0x155/0x210
[   76.982303]  do_shrink_slab+0x19e/0x4e0
[   76.982310]  shrink_slab+0x2bd/0x450
[   76.982317]  drop_slab+0xcc/0x1a0
[   76.982323]  drop_caches_sysctl_handler+0xb7/0xe0
[   76.982327]  proc_sys_call_handler+0x1bc/0x300
[   76.982331]  proc_sys_write+0x17/0x20
[   76.982334]  vfs_write+0x3d3/0x570
[   76.982342]  ksys_write+0x73/0x160
[   76.982347]  __x64_sys_write+0x1e/0x30
[   76.982352]  do_syscall_64+0x35/0x80
[   76.982357]  entry_SYSCALL_64_after_hwframe+0x63/0xcd

Function metadata_operation_failed() is called when operations failed
on dm pool metadata, dm pool will destroy and recreate metadata. So,
shrinker will be unregistered and registered, which could down write
shrinker_rwsem under pmd_write_lock.

Fix it by allocating dm_block_manager before locking pmd->root_lock
and destroying old dm_block_manager after unlocking pmd->root_lock,
then old dm_block_manager is replaced with new dm_block_manager under
pmd->root_lock. So, shrinker register/unregister could be done without
holding pmd->root_lock.

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216676
Cc: stable@vger.kernel.org #v5.2+
Fixes: e49e582965b3 ("dm thin: add read only and fail io modes")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:47 +01:00
Mike Snitzer
f472bfc95d dm cache: Fix ABBA deadlock between shrink_slab and dm_cache_metadata_abort
commit 352b837a5541690d4f843819028cf2b8be83d424 upstream.

Same ABBA deadlock pattern fixed in commit 4b60f452ec51 ("dm thin: Fix
ABBA deadlock between shrink_slab and dm_pool_abort_metadata") to
DM-cache's metadata.

Reported-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: stable@vger.kernel.org
Fixes: 028ae9f76f29 ("dm cache: add fail io mode and needs_check flag")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:41:46 +01:00