4614 Commits

Author SHA1 Message Date
Hannes Reinecke
3f47fe6446 dm: avoid filesystem lookup in dm_get_dev_t()
commit 809b1e4945774c9ec5619a8f4e2189b7b3833c0c upstream.

This reverts commit
644bda6f3460 ("dm table: fall back to getting device using name_to_dev_t()")

dm_get_dev_t() is just used to convert an arbitrary 'path' string
into a dev_t. It doesn't presume that the device is present; that
check will be done later, as the only caller is dm_get_device(),
which does a dm_get_table_device() later on, which will properly
open the device.

So if the path string already _is_ in major:minor representation
we can convert it directly, avoiding a recursion into the filesystem
to lookup the block device.

This avoids a hang in multipath_message() when the filesystem is
inaccessible.

Fixes: 644bda6f3460 ("dm table: fall back to getting device using name_to_dev_t()")
Cc: stable@vger.kernel.org
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30 13:27:14 +01:00
Qinglang Miao
98b1ad3894 dm ioctl: fix error return code in target_message
[ Upstream commit 4d7659bfbe277a43399a4a2d90fca141e70f29e1 ]

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: 2ca4c92f58f9 ("dm ioctl: prevent empty message")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29 13:44:58 +01:00
Dae R. Jeong
f2787ea3bd md: fix a warning caused by a race between concurrent md_ioctl()s
commit c731b84b51bf7fe83448bea8f56a6d55006b0615 upstream.

Syzkaller reports a warning as belows.
WARNING: CPU: 0 PID: 9647 at drivers/md/md.c:7169
...
Call Trace:
...
RIP: 0010:md_ioctl+0x4017/0x5980 drivers/md/md.c:7169
RSP: 0018:ffff888096027950 EFLAGS: 00010293
RAX: ffff88809322c380 RBX: 0000000000000932 RCX: ffffffff84e266f2
RDX: 0000000000000000 RSI: ffffffff84e299f7 RDI: 0000000000000007
RBP: ffff888096027bc0 R08: ffff88809322c380 R09: ffffed101341a482
R10: ffff888096027940 R11: ffff88809a0d240f R12: 0000000000000932
R13: ffff8880a2c14100 R14: ffff88809a0d2268 R15: ffff88809a0d2408
 __blkdev_driver_ioctl block/ioctl.c:304 [inline]
 blkdev_ioctl+0xece/0x1c10 block/ioctl.c:606
 block_ioctl+0xee/0x130 fs/block_dev.c:1930
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is caused by a race between two concurrenct md_ioctl()s closing
the array.
CPU1 (md_ioctl())                   CPU2 (md_ioctl())
------                              ------
set_bit(MD_CLOSING, &mddev->flags);
did_set_md_closing = true;
                                    WARN_ON_ONCE(test_bit(MD_CLOSING,
                                            &mddev->flags));
if(did_set_md_closing)
    clear_bit(MD_CLOSING, &mddev->flags);

Fix the warning by returning immediately if the MD_CLOSING bit is set
in &mddev->flags which indicates that the array is being closed.

Fixes: 065e519e71b2 ("md: MD_CLOSING needs to be cleared after called md_set_readonly or do_md_stop")
Reported-by: syzbot+1e46a0864c1a6e9bd3d8@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Dae R. Jeong <dae.r.jeong@kaist.ac.kr>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-29 13:44:52 +01:00
Thomas Gleixner
5b19e4a7a2 dm table: Remove BUG_ON(in_interrupt())
[ Upstream commit e7b624183d921b49ef0a96329f21647d38865ee9 ]

The BUG_ON(in_interrupt()) in dm_table_event() is a historic leftover from
a rework of the dm table code which changed the calling context.

Issuing a BUG for a wrong calling context is frowned upon and
in_interrupt() is deprecated and only covering parts of the wrong
contexts. The sanity check for the context is covered by
CONFIG_DEBUG_ATOMIC_SLEEP and other debug facilities already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29 13:44:51 +01:00
Song Liu
4c09a618ed md/raid5: fix oops during stripe resizing
commit b44c018cdf748b96b676ba09fdbc5b34fc443ada upstream.

KoWei reported crash during raid5 reshape:

[ 1032.252932] Oops: 0002 [#1] SMP PTI
[...]
[ 1032.252943] RIP: 0010:memcpy_erms+0x6/0x10
[...]
[ 1032.252947] RSP: 0018:ffffba1ac0c03b78 EFLAGS: 00010286
[ 1032.252949] RAX: 0000784ac0000000 RBX: ffff91bec3d09740 RCX: 0000000000001000
[ 1032.252951] RDX: 0000000000001000 RSI: ffff91be6781c000 RDI: 0000784ac0000000
[ 1032.252953] RBP: ffffba1ac0c03bd8 R08: 0000000000001000 R09: ffffba1ac0c03bf8
[ 1032.252954] R10: 0000000000000000 R11: 0000000000000000 R12: ffffba1ac0c03bf8
[ 1032.252955] R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000000000
[ 1032.252958] FS:  0000000000000000(0000) GS:ffff91becf500000(0000) knlGS:0000000000000000
[ 1032.252959] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1032.252961] CR2: 0000784ac0000000 CR3: 000000031780a002 CR4: 00000000001606e0
[ 1032.252962] Call Trace:
[ 1032.252969]  ? async_memcpy+0x179/0x1000 [async_memcpy]
[ 1032.252977]  ? raid5_release_stripe+0x8e/0x110 [raid456]
[ 1032.252982]  handle_stripe_expansion+0x15a/0x1f0 [raid456]
[ 1032.252988]  handle_stripe+0x592/0x1270 [raid456]
[ 1032.252993]  handle_active_stripes.isra.0+0x3cb/0x5a0 [raid456]
[ 1032.252999]  raid5d+0x35c/0x550 [raid456]
[ 1032.253002]  ? schedule+0x42/0xb0
[ 1032.253006]  ? schedule_timeout+0x10e/0x160
[ 1032.253011]  md_thread+0x97/0x160
[ 1032.253015]  ? wait_woken+0x80/0x80
[ 1032.253019]  kthread+0x104/0x140
[ 1032.253022]  ? md_start_sync+0x60/0x60
[ 1032.253024]  ? kthread_park+0x90/0x90
[ 1032.253027]  ret_from_fork+0x35/0x40

This is because cache_size_mutex was unlocked too early in resize_stripes,
which races with grow_one_stripe() that grow_one_stripe() allocates a
stripe with wrong pool_size.

Fix this issue by unlocking cache_size_mutex after updating pool_size.

Cc: <stable@vger.kernel.org> # v4.4+
Reported-by: KoWei Sung <winders@amazon.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10 10:23:55 +01:00
Zhao Heming
a43817fda7 md/bitmap: md_bitmap_get_counter returns wrong blocks
[ Upstream commit d837f7277f56e70d82b3a4a037d744854e62f387 ]

md_bitmap_get_counter() has code:

```
    if (bitmap->bp[page].hijacked ||
        bitmap->bp[page].map == NULL)
        csize = ((sector_t)1) << (bitmap->chunkshift +
                      PAGE_COUNTER_SHIFT - 1);
```

The minus 1 is wrong, this branch should report 2048 bits of space.
With "-1" action, this only report 1024 bit of space.

This bug code returns wrong blocks, but it doesn't inflence bitmap logic:
1. Most callers focus this function return value (the counter of offset),
   not the parameter blocks.
2. The bug is only triggered when hijacked is true or map is NULL.
   the hijacked true condition is very rare.
   the "map == null" only true when array is creating or resizing.
3. Even the caller gets wrong blocks, current code makes caller just to
   call md_bitmap_get_counter() one more time.

Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10 10:23:54 +01:00
Guoju Fang
fa12d56b8d bcache: fix a lost wake-up problem caused by mca_cannibalize_lock
[ Upstream commit 34cf78bf34d48dddddfeeadb44f9841d7864997a ]

This patch fix a lost wake-up problem caused by the race between
mca_cannibalize_lock and bch_cannibalize_unlock.

Consider two processes, A and B. Process A is executing
mca_cannibalize_lock, while process B takes c->btree_cache_alloc_lock
and is executing bch_cannibalize_unlock. The problem happens that after
process A executes cmpxchg and will execute prepare_to_wait. In this
timeslice process B executes wake_up, but after that process A executes
prepare_to_wait and set the state to TASK_INTERRUPTIBLE. Then process A
goes to sleep but no one will wake up it. This problem may cause bcache
device to dead.

Signed-off-by: Guoju Fang <fangguoju@gmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 20:40:03 +02:00
Ye Bin
41718a868f dm thin metadata: Avoid returning cmd->bm wild pointer on error
commit 219403d7e56f9b716ad80ab87db85d29547ee73e upstream.

Maybe __create_persistent_data_objects() caller will use PTR_ERR as a
pointer, it will lead to some strange things.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-12 11:47:37 +02:00
Ye Bin
1c1630436a dm cache metadata: Avoid returning cmd->bm wild pointer on error
commit d16ff19e69ab57e08bf908faaacbceaf660249de upstream.

Maybe __create_persistent_data_objects() caller will use PTR_ERR as a
pointer, it will lead to some strange things.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-12 11:47:37 +02:00
Kees Cook
676057c775 overflow.h: Add allocation size calculation helpers
commit 610b15c50e86eb1e4b77274fabcaea29ac72d6a8 upstream.

In preparation for replacing unchecked overflows for memory allocations,
this creates helpers for the 3 most common calculations:

array_size(a, b): 2-dimensional array
array3_size(a, b, c): 3-dimensional array
struct_size(ptr, member, n): struct followed by n-many trailing members

Each of these return SIZE_MAX on overflow instead of wrapping around.

(Additionally renames a variable named "array_size" to avoid future
collision.)

Co-developed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-03 11:21:22 +02:00
Coly Li
bc69163e59 bcache: allocate meta data pages as compound pages
commit 5fe48867856367142d91a82f2cbf7a57a24cbb70 upstream.

There are some meta data of bcache are allocated by multiple pages,
and they are used as bio bv_page for I/Os to the cache device. for
example cache_set->uuids, cache->disk_buckets, journal_write->data,
bset_tree->data.

For such meta data memory, all the allocated pages should be treated
as a single memory block. Then the memory management and underlying I/O
code can treat them more clearly.

This patch adds __GFP_COMP flag to all the location allocating >0 order
pages for the above mentioned meta data. Then their pages are treated
as compound pages now.

Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 11:02:08 +02:00
ChangSyun Peng
aefb61f0a3 md/raid5: Fix Force reconstruct-write io stuck in degraded raid5
commit a1c6ae3d9f3dd6aa5981a332a6f700cf1c25edef upstream.

In degraded raid5, we need to read parity to do reconstruct-write when
data disks fail. However, we can not read parity from
handle_stripe_dirtying() in force reconstruct-write mode.

Reproducible Steps:

1. Create degraded raid5
mdadm -C /dev/md2 --assume-clean -l5 -n3 /dev/sda2 /dev/sdb2 missing
2. Set rmw_level to 0
echo 0 > /sys/block/md2/md/rmw_level
3. IO to raid5

Now some io may be stuck in raid5. We can use handle_stripe_fill() to read
the parity in this situation.

Cc: <stable@vger.kernel.org> # v4.4+
Reviewed-by: Alex Wu <alexwu@synology.com>
Reviewed-by: BingJing Chang <bingjingc@synology.com>
Reviewed-by: Danny Shih <dannyshih@synology.com>
Signed-off-by: ChangSyun Peng <allenpeng@synology.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 11:02:08 +02:00
Coly Li
bedcb630e0 bcache: fix super block seq numbers comparision in register_cache_set()
[ Upstream commit 117f636ea695270fe492d0c0c9dfadc7a662af47 ]

In register_cache_set(), c is pointer to struct cache_set, and ca is
pointer to struct cache, if ca->sb.seq > c->sb.seq, it means this
registering cache has up to date version and other members, the in-
memory version and other members should be updated to the newer value.

But current implementation makes a cache set only has a single cache
device, so the above assumption works well except for a special case.
The execption is when a cache device new created and both ca->sb.seq and
c->sb.seq are 0, because the super block is never flushed out yet. In
the location for the following if() check,
2156         if (ca->sb.seq > c->sb.seq) {
2157                 c->sb.version           = ca->sb.version;
2158                 memcpy(c->sb.set_uuid, ca->sb.set_uuid, 16);
2159                 c->sb.flags             = ca->sb.flags;
2160                 c->sb.seq               = ca->sb.seq;
2161                 pr_debug("set version = %llu\n", c->sb.version);
2162         }
c->sb.version is not initialized yet and valued 0. When ca->sb.seq is 0,
the if() check will fail (because both values are 0), and the cache set
version, set_uuid, flags and seq won't be updated.

The above problem is hiden for current code, because the bucket size is
compatible among different super block version. And the next time when
running cache set again, ca->sb.seq will be larger than 0 and cache set
super block version will be updated properly.

But if the large bucket feature is enabled,  sb->bucket_size is the low
16bits of the bucket size. For a power of 2 value, when the actual
bucket size exceeds 16bit width, sb->bucket_size will always be 0. Then
read_super_common() will fail because the if() check to
is_power_of_2(sb->bucket_size) is false. This is how the long time
hidden bug is triggered.

This patch modifies the if() check to the following way,
2156         if (ca->sb.seq > c->sb.seq || c->sb.seq == 0) {
Then cache set's version, set_uuid, flags and seq will always be updated
corectly including for a new created cache device.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 11:01:59 +02:00
Zhao Heming
e51f5c5d5a md-cluster: fix wild pointer of unlock_all_bitmaps()
[ Upstream commit 60f80d6f2d07a6d8aee485a1d1252327eeee0c81 ]

reproduction steps:
```
node1 # mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda
/dev/sdb
node2 # mdadm -A /dev/md0 /dev/sda /dev/sdb
node1 # mdadm -G /dev/md0 -b none
mdadm: failed to remove clustered bitmap.
node1 # mdadm -S --scan
^C  <==== mdadm hung & kernel crash
```

kernel stack:
```
[  335.230657] general protection fault: 0000 [#1] SMP NOPTI
[...]
[  335.230848] Call Trace:
[  335.230873]  ? unlock_all_bitmaps+0x5/0x70 [md_cluster]
[  335.230886]  unlock_all_bitmaps+0x3d/0x70 [md_cluster]
[  335.230899]  leave+0x10f/0x190 [md_cluster]
[  335.230932]  ? md_super_wait+0x93/0xa0 [md_mod]
[  335.230947]  ? leave+0x5/0x190 [md_cluster]
[  335.230973]  md_cluster_stop+0x1a/0x30 [md_mod]
[  335.230999]  md_bitmap_free+0x142/0x150 [md_mod]
[  335.231013]  ? _cond_resched+0x15/0x40
[  335.231025]  ? mutex_lock+0xe/0x30
[  335.231056]  __md_stop+0x1c/0xa0 [md_mod]
[  335.231083]  do_md_stop+0x160/0x580 [md_mod]
[  335.231119]  ? 0xffffffffc05fb078
[  335.231148]  md_ioctl+0xa04/0x1930 [md_mod]
[  335.231165]  ? filename_lookup+0xf2/0x190
[  335.231179]  blkdev_ioctl+0x93c/0xa10
[  335.231205]  ? _cond_resched+0x15/0x40
[  335.231214]  ? __check_object_size+0xd4/0x1a0
[  335.231224]  block_ioctl+0x39/0x40
[  335.231243]  do_vfs_ioctl+0xa0/0x680
[  335.231253]  ksys_ioctl+0x70/0x80
[  335.231261]  __x64_sys_ioctl+0x16/0x20
[  335.231271]  do_syscall_64+0x65/0x1f0
[  335.231278]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
```

Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 11:01:58 +02:00
Zhiqiang Liu
be676835b2 bcache: fix potential deadlock problem in btree_gc_coalesce
[ Upstream commit be23e837333a914df3f24bf0b32e87b0331ab8d1 ]

coccicheck reports:
  drivers/md//bcache/btree.c:1538:1-7: preceding lock on line 1417

In btree_gc_coalesce func, if the coalescing process fails, we will goto
to out_nocoalesce tag directly without releasing new_nodes[i]->write_lock.
Then, it will cause a deadlock when trying to acquire new_nodes[i]->
write_lock for freeing new_nodes[i] before return.

btree_gc_coalesce func details as follows:
	if alloc new_nodes[i] fails:
		goto out_nocoalesce;
	// obtain new_nodes[i]->write_lock
	mutex_lock(&new_nodes[i]->write_lock)
	// main coalescing process
	for (i = nodes - 1; i > 0; --i)
		[snipped]
		if coalescing process fails:
			// Here, directly goto out_nocoalesce
			 // tag will cause a deadlock
			goto out_nocoalesce;
		[snipped]
	// release new_nodes[i]->write_lock
	mutex_unlock(&new_nodes[i]->write_lock)
	// coalesing succ, return
	return;
out_nocoalesce:
	btree_node_free(new_nodes[i])	// free new_nodes[i]
	// obtain new_nodes[i]->write_lock
	mutex_lock(&new_nodes[i]->write_lock);
	// set flag for reuse
	clear_bit(BTREE_NODE_dirty, &ew_nodes[i]->flags);
	// release new_nodes[i]->write_lock
	mutex_unlock(&new_nodes[i]->write_lock);

To fix the problem, we add a new tag 'out_unlock_nocoalesce' for
releasing new_nodes[i]->write_lock before out_nocoalesce tag. If
coalescing process fails, we will go to out_unlock_nocoalesce tag
for releasing new_nodes[i]->write_lock before free new_nodes[i] in
out_nocoalesce tag.

(Coly Li helps to clean up commit log format.)

Fixes: 2a285686c109816 ("bcache: btree locking rework")
Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:30 -04:00
Guoqing Jiang
9e9b57c4a2 md: don't flush workqueue unconditionally in md_open
[ 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 <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-20 10:24:17 +02:00
Sunwook Eom
779bb3625f dm verity fec: fix hash block number in verity_fec_decode
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 <speed.eom@samsung.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-05 19:14:38 +02:00
Goldwyn Rodrigues
e0a272f8fd dm flakey: check for null arg_name in parse_features()
[ Upstream commit 7690e25302dc7d0cd42b349e746fe44b44a94f2b ]

One can crash dm-flakey by specifying more feature arguments than the
number of features supplied.  Checking for null in arg_name avoids
this.

dmsetup create flakey-test --table "0 66076080 flakey /dev/sdb9 0 0 180 2 drop_writes"

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:05 +02:00
Shetty, Harshini X (EXT-Sony Mobile)
4c02b23ac2 dm verity fec: fix memory leak in verity_fec_dtr
commit 75fa601934fda23d2f15bf44b09c2401942d8e15 upstream.

Fix below kmemleak detected in verity_fec_ctr. output_pool is
allocated for each dm-verity-fec device. But it is not freed when
dm-table for the verity target is removed. Hence free the output
mempool in destructor function verity_fec_dtr.

unreferenced object 0xffffffffa574d000 (size 4096):
  comm "init", pid 1667, jiffies 4294894890 (age 307.168s)
  hex dump (first 32 bytes):
    8e 36 00 98 66 a8 0b 9b 00 00 00 00 00 00 00 00  .6..f...........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000060e82407>] __kmalloc+0x2b4/0x340
    [<00000000dd99488f>] mempool_kmalloc+0x18/0x20
    [<000000002560172b>] mempool_init_node+0x98/0x118
    [<000000006c3574d2>] mempool_init+0x14/0x20
    [<0000000008cb266e>] verity_fec_ctr+0x388/0x3b0
    [<000000000887261b>] verity_ctr+0x87c/0x8d0
    [<000000002b1e1c62>] dm_table_add_target+0x174/0x348
    [<000000002ad89eda>] table_load+0xe4/0x328
    [<000000001f06f5e9>] dm_ctl_ioctl+0x3b4/0x5a0
    [<00000000bee5fbb7>] do_vfs_ioctl+0x5dc/0x928
    [<00000000b475b8f5>] __arm64_sys_ioctl+0x70/0x98
    [<000000005361e2e8>] el0_svc_common+0xa0/0x158
    [<000000001374818f>] el0_svc_handler+0x6c/0x88
    [<000000003364e9f4>] el0_svc+0x8/0xc
    [<000000009d84cec9>] 0xffffffffffffffff

Fixes: a739ff3f543af ("dm verity: add support for forward error correction")
Depends-on: 6f1c819c219f7 ("dm: convert to bioset_init()/mempool_init()")
Cc: stable@vger.kernel.org
Signed-off-by: Harshini Shetty <harshini.x.shetty@sony.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:58:57 +02:00
Mikulas Patocka
4afa0856f0 dm cache: fix a crash due to incorrect work item cancelling
commit 7cdf6a0aae1cccf5167f3f04ecddcf648b78e289 upstream.

The crash can be reproduced by running the lvm2 testsuite test
lvconvert-thin-external-cache.sh for several minutes, e.g.:
  while :; do make check T=shell/lvconvert-thin-external-cache.sh; done

The crash happens in this call chain:
do_waker -> policy_tick -> smq_tick -> end_hotspot_period -> clear_bitset
-> memset -> __memset -- which accesses an invalid pointer in the vmalloc
area.

The work entry on the workqueue is executed even after the bitmap was
freed. The problem is that cancel_delayed_work doesn't wait for the
running work item to finish, so the work item can continue running and
re-submitting itself even after cache_postsuspend. In order to make sure
that the work item won't be running, we must use cancel_delayed_work_sync.

Also, change flush_workqueue to drain_workqueue, so that if some work item
submits itself or another work item, we are properly waiting for both of
them.

Fixes: c6b4fcbad044 ("dm: add cache target")
Cc: stable@vger.kernel.org # v3.9
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-11 07:53:14 +01:00
Coly Li
fdfb5da588 bcache: explicity type cast in bset_bkey_last()
[ Upstream commit 7c02b0055f774ed9afb6e1c7724f33bf148ffdc0 ]

In bset.h, macro bset_bkey_last() is defined as,
    bkey_idx((struct bkey *) (i)->d, (i)->keys)

Parameter i can be variable type of data structure, the macro always
works once the type of struct i has member 'd' and 'keys'.

bset_bkey_last() is also used in macro csum_set() to calculate the
checksum of a on-disk data structure. When csum_set() is used to
calculate checksum of on-disk bcache super block, the parameter 'i'
data type is struct cache_sb_disk. Inside struct cache_sb_disk (also in
struct cache_sb) the member keys is __u16 type. But bkey_idx() expects
unsigned int (a 32bit width), so there is problem when sending
parameters via stack to call bkey_idx().

Sparse tool from Intel 0day kbuild system reports this incompatible
problem. bkey_idx() is part of user space API, so the simplest fix is
to cast the (i)->keys to unsigned int type in macro bset_bkey_last().

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-28 15:42:41 +01:00
Mike Snitzer
e68f18b0a7 dm: fix potential for q->make_request_fn NULL pointer
commit 47ace7e012b9f7ad71d43ac9063d335ea3d6820b upstream.

Move blk_queue_make_request() to dm.c:alloc_dev() so that
q->make_request_fn is never NULL during the lifetime of a DM device
(even one that is created without a DM table).

Otherwise generic_make_request() will crash simply by doing:
  dmsetup create -n test
  mount /dev/dm-N /mnt

While at it, move ->congested_data initialization out of
dm.c:alloc_dev() and into the bio-based specific init method.

Reported-by: Stefan Bader <stefan.bader@canonical.com>
BugLink: https://bugs.launchpad.net/bugs/1860231
Fixes: ff36ab34583a ("dm: remove request-based logic from make_request_fn wrapper")
Depends-on: c12c9a3c3860c ("dm: various cleanups to md->queue initialization code")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
[smb: adjusted for context and dm_init_md_queue() exitsting in older
      kernels, and congested_data embedded in backing_dev_info]
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:31:10 -05:00
Joe Thornber
17c0d259c1 dm space map common: fix to ensure new block isn't already in use
commit 4feaef830de7ffdd8352e1fe14ad3bf13c9688f8 upstream.

The space-maps track the reference counts for disk blocks allocated by
both the thin-provisioning and cache targets.  There are variants for
tracking metadata blocks and data blocks.

Transactionality is implemented by never touching blocks from the
previous transaction, so we can rollback in the event of a crash.

When allocating a new block we need to ensure the block is free (has
reference count of 0) in both the current and previous transaction.
Prior to this fix we were doing this by searching for a free block in
the previous transaction, and relying on a 'begin' counter to track
where the last allocation in the current transaction was.  This
'begin' field was not being updated in all code paths (eg, increment
of a data block reference count due to breaking sharing of a neighbour
block in the same btree leaf).

This fix keeps the 'begin' field, but now it's just a hint to speed up
the search.  Instead the current transaction is searched for a free
block, and then the old transaction is double checked to ensure it's
free.  Much simpler.

This fixes reports of sm_disk_new_block()'s BUG_ON() triggering when
DM thin-provisioning's snapshots are heavily used.

Reported-by: Eric Wheeler <dm-devel@lists.ewheeler.net>
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:31:01 -05:00
Andy Shevchenko
b547564041 md: Avoid namespace collision with bitmap API
commit e64e4018d572710c44f42c923d4ac059f0a23320 upstream.

bitmap API (include/linux/bitmap.h) has 'bitmap' prefix for its methods.

On the other hand MD bitmap API is special case.
Adding 'md' prefix to it to avoid name space collision.

No functional changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Shaohua Li <shli@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
[only take the bitmap_free change for stable - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29 10:24:40 +01:00
Dan Carpenter
94e7963c76 bcache: silence static checker warning
commit da22f0eea555baf9b0a84b52afe56db2052cfe8d upstream.

In olden times, closure_return() used to have a hidden return built in.
We removed the hidden return but forgot to add a new return here.  If
"c" were NULL we would oops on the next line, but fortunately "c" is
never NULL.  Let's just remove the if statement.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29 10:24:40 +01:00
Mikulas Patocka
5dbde467cc block: fix an integer overflow in logical block size
commit ad6bf88a6c19a39fb3b0045d78ea880325dfcf15 upstream.

Logical block size has type unsigned short. That means that it can be at
most 32768. However, there are architectures that can run with 64k pages
(for example arm64) and on these architectures, it may be possible to
create block devices with 64k block size.

For exmaple (run this on an architecture with 64k pages):

Mount will fail with this error because it tries to read the superblock using 2-sector
access:
  device-mapper: writecache: I/O is not aligned, sector 2, size 1024, block size 65536
  EXT4-fs (dm-0): unable to read superblock

This patch changes the logical block size from unsigned short to unsigned
int to avoid the overflow.

Cc: stable@vger.kernel.org
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23 08:19:38 +01:00
Zhiqiang Liu
7455901cd8 md: raid1: check rdev before reference in raid1_sync_request func
[ Upstream commit 028288df635f5a9addd48ac4677b720192747944 ]

In raid1_sync_request func, rdev should be checked before reference.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-12 11:24:10 +01:00
Coly Li
116d44d11e bcache: at least try to shrink 1 node in bch_mca_scan()
[ Upstream commit 9fcc34b1a6dd4b8e5337e2b6ef45e428897eca6b ]

In bch_mca_scan(), the number of shrinking btree node is calculated
by code like this,
	unsigned long nr = sc->nr_to_scan;

        nr /= c->btree_pages;
        nr = min_t(unsigned long, nr, mca_can_free(c));
variable sc->nr_to_scan is number of objects (here is bcache B+tree
nodes' number) to shrink, and pointer variable sc is sent from memory
management code as parametr of a callback.

If sc->nr_to_scan is smaller than c->btree_pages, after the above
calculation, variable 'nr' will be 0 and nothing will be shrunk. It is
frequeently observed that only 1 or 2 is set to sc->nr_to_scan and make
nr to be zero. Then bch_mca_scan() will do nothing more then acquiring
and releasing mutex c->bucket_lock.

This patch checkes whether nr is 0 after the above calculation, if 0
is the result then set 1 to variable 'n'. Then at least bch_mca_scan()
will try to shrink a single B+tree node.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-04 13:40:56 +01:00
Hou Tao
e861c9bc0f dm btree: increase rebalance threshold in __rebalance2()
commit 474e559567fa631dea8fb8407ab1b6090c903755 upstream.

We got the following warnings from thin_check during thin-pool setup:

  $ thin_check /dev/vdb
  examining superblock
  examining devices tree
    missing devices: [1, 84]
      too few entries in btree_node: 41, expected at least 42 (block 138, max_entries = 126)
  examining mapping tree

The phenomenon is the number of entries in one node of details_info tree is
less than (max_entries / 3). And it can be easily reproduced by the following
procedures:

  $ new a thin pool
  $ presume the max entries of details_info tree is 126
  $ new 127 thin devices (e.g. 1~127) to make the root node being full
    and then split
  $ remove the first 43 (e.g. 1~43) thin devices to make the children
    reblance repeatedly
  $ stop the thin pool
  $ thin_check

The root cause is that the B-tree removal procedure in __rebalance2()
doesn't guarantee the invariance: the minimal number of entries in
non-root node should be >= (max_entries / 3).

Simply fix the problem by increasing the rebalance threshold to
make sure the number of entries in each child will be greater
than or equal to (max_entries / 3 + 1), so no matter which
child is used for removal, the number will still be valid.

Cc: stable@vger.kernel.org
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-21 10:42:32 +01:00
Sweet Tea
1ed7c9f45f dm flakey: Properly corrupt multi-page bios.
[ Upstream commit a00f5276e26636cbf72f24f79831026d2e2868e7 ]

The flakey target is documented to be able to corrupt the Nth byte in
a bio, but does not corrupt byte indices after the first biovec in the
bio. Change the corrupting function to actually corrupt the Nth byte
no matter in which biovec that index falls.

A test device generating two-page bios, atop a flakey device configured
to corrupt a byte index on the second page, verified both the failure
to corrupt before this patch and the expected corruption after this
change.

Signed-off-by: John Dorminy <jdorminy@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-05 15:34:34 +01:00
Bart Van Assche
5de1a7fc74 dm: use blk_set_queue_dying() in __dm_destroy()
commit 2e91c3694181dc500faffec16c5aaa0ac5e15449 upstream.

After QUEUE_FLAG_DYING has been set any code that is waiting in
get_request() should be woken up.  But to get this behaviour
blk_set_queue_dying() must be used instead of only setting
QUEUE_FLAG_DYING.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-28 18:29:02 +01:00
Shenghui Wang
7919356b72 bcache: recal cached_dev_sectors on detach
[ Upstream commit 46010141da6677b81cc77f9b47f8ac62bd1cbfd3 ]

Recal cached_dev_sectors on cached_dev detached, as recal done on
cached_dev attached.

Update the cached_dev_sectors before bcache_device_detach called
as bcache_device_detach will set bcache_device->c to NULL.

Signed-off-by: Shenghui Wang <shhuiw@foxmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-25 09:53:42 +01:00
Kent Overstreet
7ff8f2104c dm: Use kzalloc for all structs with embedded biosets/mempools
[ Upstream commit d377535405686f735b90a8ad4ba269484cd7c96e ]

mempool_init()/bioset_init() require that the mempools/biosets be zeroed
first; they probably should not _require_ this, but not allocating those
structs with kzalloc is a fairly nonsensical thing to do (calling
mempool_exit()/bioset_exit() on an uninitialized mempool/bioset is legal
and safe, but only works if said memory was zeroed.)

Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 12:18:01 +01:00
Mikulas Patocka
37524335ac dm snapshot: rework COW throttling to fix deadlock
[ Upstream commit b21555786f18cd77f2311ad89074533109ae3ffa ]

Commit 721b1d98fb517a ("dm snapshot: Fix excessive memory usage and
workqueue stalls") introduced a semaphore to limit the maximum number of
in-flight kcopyd (COW) jobs.

The implementation of this throttling mechanism is prone to a deadlock:

1. One or more threads write to the origin device causing COW, which is
   performed by kcopyd.

2. At some point some of these threads might reach the s->cow_count
   semaphore limit and block in down(&s->cow_count), holding a read lock
   on _origins_lock.

3. Someone tries to acquire a write lock on _origins_lock, e.g.,
   snapshot_ctr(), which blocks because the threads at step (2) already
   hold a read lock on it.

4. A COW operation completes and kcopyd runs dm-snapshot's completion
   callback, which ends up calling pending_complete().
   pending_complete() tries to resubmit any deferred origin bios. This
   requires acquiring a read lock on _origins_lock, which blocks.

   This happens because the read-write semaphore implementation gives
   priority to writers, meaning that as soon as a writer tries to enter
   the critical section, no readers will be allowed in, until all
   writers have completed their work.

   So, pending_complete() waits for the writer at step (3) to acquire
   and release the lock. This writer waits for the readers at step (2)
   to release the read lock and those readers wait for
   pending_complete() (the kcopyd thread) to signal the s->cow_count
   semaphore: DEADLOCK.

The above was thoroughly analyzed and documented by Nikos Tsironis as
part of his initial proposal for fixing this deadlock, see:
https://www.redhat.com/archives/dm-devel/2019-October/msg00001.html

Fix this deadlock by reworking COW throttling so that it waits without
holding any locks. Add a variable 'in_progress' that counts how many
kcopyd jobs are running. A function wait_for_in_progress() will sleep if
'in_progress' is over the limit. It drops _origins_lock in order to
avoid the deadlock.

Reported-by: Guruswamy Basavaiah <guru2018@gmail.com>
Reported-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Nikos Tsironis <ntsironis@arrikto.com>
Tested-by: Nikos Tsironis <ntsironis@arrikto.com>
Fixes: 721b1d98fb51 ("dm snapshot: Fix excessive memory usage and workqueue stalls")
Cc: stable@vger.kernel.org # v5.0+
Depends-on: 4a3f111a73a8c ("dm snapshot: introduce account_start_copy() and account_end_copy()")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 12:18:00 +01:00
Mikulas Patocka
5de1e3a9e9 dm snapshot: introduce account_start_copy() and account_end_copy()
[ Upstream commit a2f83e8b0c82c9500421a26c49eb198b25fcdea3 ]

This simple refactoring moves code for modifying the semaphore cow_count
into separate functions to prepare for changes that will extend these
methods to provide for a more sophisticated mechanism for COW
throttling.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 12:18:00 +01:00
Mikulas Patocka
0685a2565a dm snapshot: use mutex instead of rw_semaphore
[ Upstream commit ae1093be5a0ef997833e200a0dafb9ed0b1ff4fe ]

The rw_semaphore is acquired for read only in two places, neither is
performance-critical.  So replace it with a mutex -- which is more
efficient.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 12:17:59 +01:00
Xiao Ni
aa06376f21 md/raid6: Set R5_ReadError when there is read failure on parity disk
commit 143f6e733b73051cd22dcb80951c6c929da413ce upstream.

7471fb77ce4d ("md/raid6: Fix anomily when recovering a single device in
RAID6.") avoids rereading P when it can be computed from other members.
However, this misses the chance to re-write the right data to P. This
patch sets R5_ReadError if the re-read fails.

Also, when re-read is skipped, we also missed the chance to reset
rdev->read_errors to 0. It can fail the disk when there are many read
errors on P member disk (other disks don't have read error)

V2: upper layer read request don't read parity/Q data. So there is no
need to consider such situation.

This is Reported-by: kbuild test robot <lkp@intel.com>

Fixes: 7471fb77ce4d ("md/raid6: Fix anomily when recovering a single device in RAID6.")
Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05 12:30:34 +02:00
Yufen Yu
5bad5054ec md/raid1: fail run raid1 array when active disk less than one
[ Upstream commit 07f1a6850c5d5a65c917c3165692b5179ac4cb6b ]

When run test case:
  mdadm -CR /dev/md1 -l 1 -n 4 /dev/sd[a-d] --assume-clean --bitmap=internal
  mdadm -S /dev/md1
  mdadm -A /dev/md1 /dev/sd[b-c] --run --force

  mdadm --zero /dev/sda
  mdadm /dev/md1 -a /dev/sda

  echo offline > /sys/block/sdc/device/state
  echo offline > /sys/block/sdb/device/state
  sleep 5
  mdadm -S /dev/md1

  echo running > /sys/block/sdb/device/state
  echo running > /sys/block/sdc/device/state
  mdadm -A /dev/md1 /dev/sd[a-c] --run --force

mdadm run fail with kernel message as follow:
[  172.986064] md: kicking non-fresh sdb from array!
[  173.004210] md: kicking non-fresh sdc from array!
[  173.022383] md/raid1:md1: active with 0 out of 4 mirrors
[  173.022406] md1: failed to create bitmap (-5)

In fact, when active disk in raid1 array less than one, we
need to return fail in raid1_run().

Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05 12:30:26 +02:00
Guoqing Jiang
bdab1a27d9 md: don't set In_sync if array is frozen
[ Upstream commit 062f5b2ae12a153644c765e7ba3b0f825427be1d ]

When a disk is added to array, the following path is called in mdadm.

Manage_subdevs -> sysfs_freeze_array
               -> Manage_add
               -> sysfs_set_str(&info, NULL, "sync_action","idle")

Then from kernel side, Manage_add invokes the path (add_new_disk ->
validate_super = super_1_validate) to set In_sync flag.

Since In_sync means "device is in_sync with rest of array", and the new
added disk need to resync thread to help the synchronization of data.
And md_reap_sync_thread would call spare_active to set In_sync for the
new added disk finally. So don't set In_sync if array is in frozen.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05 12:30:21 +02:00
Guoqing Jiang
f14b1b3264 md: don't call spare_active in md_reap_sync_thread if all member devices can't work
[ Upstream commit 0d8ed0e9bf9643f27f4816dca61081784dedb38d ]

When add one disk to array, the md_reap_sync_thread is responsible
to activate the spare and set In_sync flag for the new member in
spare_active().

But if raid1 has one member disk A, and disk B is added to the array.
Then we offline A before all the datas are synchronized from A to B,
obviously B doesn't have the latest data as A, but B is still marked
with In_sync flag.

So let's not call spare_active under the condition, otherwise B is
still showed with 'U' state which is not correct.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05 12:30:21 +02:00
Mikulas Patocka
190db74e14 dm table: fix invalid memory accesses with too high sector number
commit 1cfd5d3399e87167b7f9157ef99daa0e959f395d upstream.

If the sector number is too high, dm_table_find_target() should return a
pointer to a zeroed dm_target structure (the caller should test it with
dm_target_is_valid).

However, for some table sizes, the code in dm_table_find_target() that
performs btree lookup will access out of bound memory structures.

Fix this bug by testing the sector number at the beginning of
dm_table_find_target(). Also, add an "inline" keyword to the function
dm_table_get_size() because this is a hot path.

Fixes: 512875bd9661 ("dm: table detect io beyond device")
Cc: stable@vger.kernel.org
Reported-by: Zhang Tao <kontais@zoho.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-06 10:19:39 +02:00
ZhangXiaoxu
f4f7e6d57b dm space map metadata: fix missing store of apply_bops() return value
commit ae148243d3f0816b37477106c05a2ec7d5f32614 upstream.

In commit 6096d91af0b6 ("dm space map metadata: fix occasional leak
of a metadata block on resize"), we refactor the commit logic to a new
function 'apply_bops'.  But when that logic was replaced in out() the
return value was not stored.  This may lead out() returning a wrong
value to the caller.

Fixes: 6096d91af0b6 ("dm space map metadata: fix occasional leak of a metadata block on resize")
Cc: stable@vger.kernel.org
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-06 10:19:38 +02:00
ZhangXiaoxu
efe36a4256 dm btree: fix order of block initialization in btree_split_beneath
commit e4f9d6013820d1eba1432d51dd1c5795759aa77f upstream.

When btree_split_beneath() splits a node to two new children, it will
allocate two blocks: left and right.  If right block's allocation
failed, the left block will be unlocked and marked dirty.  If this
happened, the left block'ss content is zero, because it wasn't
initialized with the btree struct before the attempot to allocate the
right block.  Upon return, when flushing the left block to disk, the
validator will fail when check this block.  Then a BUG_ON is raised.

Fix this by completely initializing the left block before allocating and
initializing the right block.

Fixes: 4dcb8b57df359 ("dm btree: fix leak of bufio-backed block in btree_split_beneath error path")
Cc: stable@vger.kernel.org
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-06 10:19:38 +02:00
Mikulas Patocka
b90594573b Revert "dm bufio: fix deadlock with loop device"
commit cf3591ef832915892f2499b7e54b51d4c578b28c upstream.

Revert the commit bd293d071ffe65e645b4d8104f9d8fe15ea13862. The proper
fix has been made available with commit d0a255e795ab ("loop: set
PF_MEMALLOC_NOIO for the worker thread").

Note that the fix offered by commit bd293d071ffe doesn't really prevent
the deadlock from occuring - if we look at the stacktrace reported by
Junxiao Bi, we see that it hangs in bit_wait_io and not on the mutex -
i.e. it has already successfully taken the mutex. Changing the mutex
from mutex_lock to mutex_trylock won't help with deadlocks that happen
afterwards.

PID: 474    TASK: ffff8813e11f4600  CPU: 10  COMMAND: "kswapd0"
   #0 [ffff8813dedfb938] __schedule at ffffffff8173f405
   #1 [ffff8813dedfb990] schedule at ffffffff8173fa27
   #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec
   #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186
   #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f
   #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8
   #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81
   #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio]
   #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio]
   #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio]
  #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce
  #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778
  #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f
  #13 [ffff8813dedfbec0] kthread at ffffffff810a8428
  #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Fixes: bd293d071ffe ("dm bufio: fix deadlock with loop device")
Depends-on: d0a255e795ab ("loop: set PF_MEMALLOC_NOIO for the worker thread")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-06 10:19:36 +02:00
Junxiao Bi
0d78b27b83 dm bufio: fix deadlock with loop device
commit bd293d071ffe65e645b4d8104f9d8fe15ea13862 upstream.

When thin-volume is built on loop device, if available memory is low,
the following deadlock can be triggered:

One process P1 allocates memory with GFP_FS flag, direct alloc fails,
memory reclaim invokes memory shrinker in dm_bufio, dm_bufio_shrink_scan()
runs, mutex dm_bufio_client->lock is acquired, then P1 waits for dm_buffer
IO to complete in __try_evict_buffer().

But this IO may never complete if issued to an underlying loop device
that forwards it using direct-IO, which allocates memory using
GFP_KERNEL (see: do_blockdev_direct_IO()).  If allocation fails, memory
reclaim will invoke memory shrinker in dm_bufio, dm_bufio_shrink_scan()
will be invoked, and since the mutex is already held by P1 the loop
thread will hang, and IO will never complete.  Resulting in ABBA
deadlock.

Cc: stable@vger.kernel.org
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-04 09:33:32 +02:00
Coly Li
06ff4163bb bcache: check c->gc_thread by IS_ERR_OR_NULL in cache_set_flush()
[ Upstream commit b387e9b58679c60f5b1e4313939bd4878204fc37 ]

When system memory is in heavy pressure, bch_gc_thread_start() from
run_cache_set() may fail due to out of memory. In such condition,
c->gc_thread is assigned to -ENOMEM, not NULL pointer. Then in following
failure code path bch_cache_set_error(), when cache_set_flush() gets
called, the code piece to stop c->gc_thread is broken,
         if (!IS_ERR_OR_NULL(c->gc_thread))
                 kthread_stop(c->gc_thread);

And KASAN catches such NULL pointer deference problem, with the warning
information:

[  561.207881] ==================================================================
[  561.207900] BUG: KASAN: null-ptr-deref in kthread_stop+0x3b/0x440
[  561.207904] Write of size 4 at addr 000000000000001c by task kworker/15:1/313

[  561.207913] CPU: 15 PID: 313 Comm: kworker/15:1 Tainted: G        W         5.0.0-vanilla+ #3
[  561.207916] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE136T-2.10]- 03/22/2019
[  561.207935] Workqueue: events cache_set_flush [bcache]
[  561.207940] Call Trace:
[  561.207948]  dump_stack+0x9a/0xeb
[  561.207955]  ? kthread_stop+0x3b/0x440
[  561.207960]  ? kthread_stop+0x3b/0x440
[  561.207965]  kasan_report+0x176/0x192
[  561.207973]  ? kthread_stop+0x3b/0x440
[  561.207981]  kthread_stop+0x3b/0x440
[  561.207995]  cache_set_flush+0xd4/0x6d0 [bcache]
[  561.208008]  process_one_work+0x856/0x1620
[  561.208015]  ? find_held_lock+0x39/0x1d0
[  561.208028]  ? drain_workqueue+0x380/0x380
[  561.208048]  worker_thread+0x87/0xb80
[  561.208058]  ? __kthread_parkme+0xb6/0x180
[  561.208067]  ? process_one_work+0x1620/0x1620
[  561.208072]  kthread+0x326/0x3e0
[  561.208079]  ? kthread_create_worker_on_cpu+0xc0/0xc0
[  561.208090]  ret_from_fork+0x3a/0x50
[  561.208110] ==================================================================
[  561.208113] Disabling lock debugging due to kernel taint
[  561.208115] irq event stamp: 11800231
[  561.208126] hardirqs last  enabled at (11800231): [<ffffffff83008538>] do_syscall_64+0x18/0x410
[  561.208127] BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
[  561.208129] #PF error: [WRITE]
[  561.312253] hardirqs last disabled at (11800230): [<ffffffff830052ff>] trace_hardirqs_off_thunk+0x1a/0x1c
[  561.312259] softirqs last  enabled at (11799832): [<ffffffff850005c7>] __do_softirq+0x5c7/0x8c3
[  561.405975] PGD 0 P4D 0
[  561.442494] softirqs last disabled at (11799821): [<ffffffff831add2c>] irq_exit+0x1ac/0x1e0
[  561.791359] Oops: 0002 [#1] SMP KASAN NOPTI
[  561.791362] CPU: 15 PID: 313 Comm: kworker/15:1 Tainted: G    B   W         5.0.0-vanilla+ #3
[  561.791363] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE136T-2.10]- 03/22/2019
[  561.791371] Workqueue: events cache_set_flush [bcache]
[  561.791374] RIP: 0010:kthread_stop+0x3b/0x440
[  561.791376] Code: 00 00 65 8b 05 26 d5 e0 7c 89 c0 48 0f a3 05 ec aa df 02 0f 82 dc 02 00 00 4c 8d 63 20 be 04 00 00 00 4c 89 e7 e8 65 c5 53 00 <f0> ff 43 20 48 8d 7b 24 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48
[  561.791377] RSP: 0018:ffff88872fc8fd10 EFLAGS: 00010286
[  561.838895] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838916] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838934] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838948] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838966] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838979] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838996] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  563.067028] RAX: 0000000000000000 RBX: fffffffffffffffc RCX: ffffffff832dd314
[  563.067030] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000297
[  563.067032] RBP: ffff88872fc8fe88 R08: fffffbfff0b8213d R09: fffffbfff0b8213d
[  563.067034] R10: 0000000000000001 R11: fffffbfff0b8213c R12: 000000000000001c
[  563.408618] R13: ffff88dc61cc0f68 R14: ffff888102b94900 R15: ffff88dc61cc0f68
[  563.408620] FS:  0000000000000000(0000) GS:ffff888f7dc00000(0000) knlGS:0000000000000000
[  563.408622] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  563.408623] CR2: 000000000000001c CR3: 0000000f48a1a004 CR4: 00000000007606e0
[  563.408625] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  563.408627] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  563.904795] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  563.915796] PKRU: 55555554
[  563.915797] Call Trace:
[  563.915807]  cache_set_flush+0xd4/0x6d0 [bcache]
[  563.915812]  process_one_work+0x856/0x1620
[  564.001226] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.033563]  ? find_held_lock+0x39/0x1d0
[  564.033567]  ? drain_workqueue+0x380/0x380
[  564.033574]  worker_thread+0x87/0xb80
[  564.062823] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.118042]  ? __kthread_parkme+0xb6/0x180
[  564.118046]  ? process_one_work+0x1620/0x1620
[  564.118048]  kthread+0x326/0x3e0
[  564.118050]  ? kthread_create_worker_on_cpu+0xc0/0xc0
[  564.167066] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.252441]  ret_from_fork+0x3a/0x50
[  564.252447] Modules linked in: msr rpcrdma sunrpc rdma_ucm ib_iser ib_umad rdma_cm ib_ipoib i40iw configfs iw_cm ib_cm libiscsi scsi_transport_iscsi mlx4_ib ib_uverbs mlx4_en ib_core nls_iso8859_1 nls_cp437 vfat fat intel_rapl skx_edac x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ses raid0 aesni_intel cdc_ether enclosure usbnet ipmi_ssif joydev aes_x86_64 i40e scsi_transport_sas mii bcache md_mod crypto_simd mei_me ioatdma crc64 ptp cryptd pcspkr i2c_i801 mlx4_core glue_helper pps_core mei lpc_ich dca wmi ipmi_si ipmi_devintf nd_pmem dax_pmem nd_btt ipmi_msghandler device_dax pcc_cpufreq button hid_generic usbhid mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect xhci_pci sysimgblt fb_sys_fops xhci_hcd ttm megaraid_sas drm usbcore nfit libnvdimm sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua efivarfs
[  564.299390] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.348360] CR2: 000000000000001c
[  564.348362] ---[ end trace b7f0e5cc7b2103b0 ]---

Therefore, it is not enough to only check whether c->gc_thread is NULL,
we should use IS_ERR_OR_NULL() to check both NULL pointer and error
value.

This patch changes the above buggy code piece in this way,
         if (!IS_ERR_OR_NULL(c->gc_thread))
                 kthread_stop(c->gc_thread);

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04 09:33:23 +02:00
Milan Broz
7357febe9e dm verity: use message limit for data block corruption message
[ Upstream commit 2eba4e640b2c4161e31ae20090a53ee02a518657 ]

DM verity should also use DMERR_LIMIT to limit repeat data block
corruption messages.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21 09:06:07 +02:00
Mariusz Tkaczyk
4f7347010e md: fix for divide error in status_resync
[ Upstream commit 9642fa73d073527b0cbc337cc17a47d545d82cd2 ]

Stopping external metadata arrays during resync/recovery causes
retries, loop of interrupting and starting reconstruction, until it
hit at good moment to stop completely. While these retries
curr_mark_cnt can be small- especially on HDD drives, so subtraction
result can be smaller than 0. However it is casted to uint without
checking. As a result of it the status bar in /proc/mdstat while stopping
is strange (it jumps between 0% and 99%).

The real problem occurs here after commit 72deb455b5ec ("block: remove
CONFIG_LBDAF"). Sector_div() macro has been changed, now the
divisor is casted to uint32. For db = -8 the divisior(db/32-1) becomes 0.

Check if db value can be really counted and replace these macro by
div64_u64() inline.

Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21 09:05:56 +02:00
Coly Li
4cf6bb23ac bcache: fix stack corruption by PRECEDING_KEY()
commit 31b90956b124240aa8c63250243ae1a53585c5e2 upstream.

Recently people report bcache code compiled with gcc9 is broken, one of
the buggy behavior I observe is that two adjacent 4KB I/Os should merge
into one but they don't. Finally it turns out to be a stack corruption
caused by macro PRECEDING_KEY().

See how PRECEDING_KEY() is defined in bset.h,
437 #define PRECEDING_KEY(_k)                                       \
438 ({                                                              \
439         struct bkey *_ret = NULL;                               \
440                                                                 \
441         if (KEY_INODE(_k) || KEY_OFFSET(_k)) {                  \
442                 _ret = &KEY(KEY_INODE(_k), KEY_OFFSET(_k), 0);  \
443                                                                 \
444                 if (!_ret->low)                                 \
445                         _ret->high--;                           \
446                 _ret->low--;                                    \
447         }                                                       \
448                                                                 \
449         _ret;                                                   \
450 })

At line 442, _ret points to address of a on-stack variable combined by
KEY(), the life range of this on-stack variable is in line 442-446,
once _ret is returned to bch_btree_insert_key(), the returned address
points to an invalid stack address and this address is overwritten in
the following called bch_btree_iter_init(). Then argument 'search' of
bch_btree_iter_init() points to some address inside stackframe of
bch_btree_iter_init(), exact address depends on how the compiler
allocates stack space. Now the stack is corrupted.

Fixes: 0eacac22034c ("bcache: PRECEDING_KEY()")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Rolf Fokkens <rolf@rolffokkens.nl>
Reviewed-by: Pierre JUHEN <pierre.juhen@orange.fr>
Tested-by: Shenghui Wang <shhuiw@foxmail.com>
Tested-by: Pierre JUHEN <pierre.juhen@orange.fr>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Nix <nix@esperi.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-22 08:17:19 +02:00
Arnd Bergmann
56df2dbea3 bcache: avoid clang -Wunintialized warning
[ Upstream commit 78d4eb8ad9e1d413449d1b7a060f50b6efa81ebd ]

clang has identified a code path in which it thinks a
variable may be unused:

drivers/md/bcache/alloc.c:333:4: error: variable 'bucket' is used uninitialized whenever 'if' condition is false
      [-Werror,-Wsometimes-uninitialized]
                        fifo_pop(&ca->free_inc, bucket);
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/md/bcache/util.h:219:27: note: expanded from macro 'fifo_pop'
 #define fifo_pop(fifo, i)       fifo_pop_front(fifo, (i))
                                ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/md/bcache/util.h:189:6: note: expanded from macro 'fifo_pop_front'
        if (_r) {                                                       \
            ^~
drivers/md/bcache/alloc.c:343:46: note: uninitialized use occurs here
                        allocator_wait(ca, bch_allocator_push(ca, bucket));
                                                                  ^~~~~~
drivers/md/bcache/alloc.c:287:7: note: expanded from macro 'allocator_wait'
                if (cond)                                               \
                    ^~~~
drivers/md/bcache/alloc.c:333:4: note: remove the 'if' if its condition is always true
                        fifo_pop(&ca->free_inc, bucket);
                        ^
drivers/md/bcache/util.h:219:27: note: expanded from macro 'fifo_pop'
 #define fifo_pop(fifo, i)       fifo_pop_front(fifo, (i))
                                ^
drivers/md/bcache/util.h:189:2: note: expanded from macro 'fifo_pop_front'
        if (_r) {                                                       \
        ^
drivers/md/bcache/alloc.c:331:15: note: initialize the variable 'bucket' to silence this warning
                        long bucket;
                                   ^

This cannot happen in practice because we only enter the loop
if there is at least one element in the list.

Slightly rearranging the code makes this clearer to both the
reader and the compiler, which avoids the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:48:16 -07:00