linux-stable.git/drivers/block/null_blk, branch v6.10

null_blk: fix validation of block size

2024-06-05T18:12:54+00:00

Block size should be between 512 and PAGE_SIZE and be a power of 2. The current
check does not validate this, so update the check.

Without this patch, null_blk would Oops due to a null pointer deref when
loaded with bs=1536 [1].

Link: https://lore.kernel.org/all/87wmn8mocd.fsf@metaspace.dk/

Signed-off-by: Andreas Hindborg 
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20240603192645.977968-1-nmi@metaspace.dk
[axboe: remove unnecessary braces and != 0 check]
Signed-off-by: Jens Axboe

null_blk: Do not allow runt zone with zone capacity smaller then zone size

2024-05-30T21:03:52+00:00

A zoned device with a smaller last zone together with a zone capacity
smaller than the zone size does make any sense as that does not
correspond to any possible setup for a real device:
1) For ZNS and zoned UFS devices, all zones are always the same size.
2) For SMR HDDs, all zones always have the same capacity.
In other words, if we have a smaller last runt zone, then this zone
capacity should always be equal to the zone size.

Add a check in null_init_zoned_dev() to prevent a configuration to have
both a smaller zone size and a zone capacity smaller than the zone size.

Signed-off-by: Damien Le Moal 
Reviewed-by: Niklas Cassel 
Reviewed-by: Bart Van Assche 
Link: https://lore.kernel.org/r/20240530054035.491497-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe

null_blk: Print correct max open zones limit in null_init_zoned_dev()

2024-05-28T12:54:21+00:00

When changing the maximum number of open zones, print that number
instead of the total number of zones.

Fixes: dc4d137ee3b7 ("null_blk: add support for max open/active zone limit for zoned devices")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal 
Reviewed-by: Niklas Cassel 
Link: https://lore.kernel.org/r/20240528062852.437599-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe

null_blk: Fix return value of nullb_device_power_store()

2024-05-27T19:56:58+00:00

When powering on a null_blk device that is not already on, the return
value ret that is initialized to be count is reused to check the return
value of null_add_dev(), leading to nullb_device_power_store() to return
null_add_dev() return value (0 on success) instead of "count".
So make sure to set ret to be equal to count when there are no errors.

Fixes: a2db328b0839 ("null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues'")
Signed-off-by: Damien Le Moal 
Reviewed-by: Yu Kuai 
Reviewed-by: Kanchan Joshi 
Link: https://lore.kernel.org/r/20240527043445.235267-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe

null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues'

2024-05-23T12:58:13+00:00

Writing 'power' and 'submit_queues' concurrently will trigger kernel
panic:

Test script:

modprobe null_blk nr_devices=0
mkdir -p /sys/kernel/config/nullb/nullb0
while true; do echo 1 > submit_queues; echo 4 > submit_queues; done &
while true; do echo 1 > power; echo 0 > power; done

Test result:

BUG: kernel NULL pointer dereference, address: 0000000000000148
Oops: 0000 [#1] PREEMPT SMP
RIP: 0010:__lock_acquire+0x41d/0x28f0
Call Trace:
 
 lock_acquire+0x121/0x450
 down_write+0x5f/0x1d0
 simple_recursive_removal+0x12f/0x5c0
 blk_mq_debugfs_unregister_hctxs+0x7c/0x100
 blk_mq_update_nr_hw_queues+0x4a3/0x720
 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk]
 nullb_device_submit_queues_store+0x79/0xf0 [null_blk]
 configfs_write_iter+0x119/0x1e0
 vfs_write+0x326/0x730
 ksys_write+0x74/0x150

This is because del_gendisk() can concurrent with
blk_mq_update_nr_hw_queues():

nullb_device_power_store	nullb_apply_submit_queues
 null_del_dev
 del_gendisk
				 nullb_update_nr_hw_queues
				  if (!dev->nullb)
				  // still set while gendisk is deleted
				   return 0
				  blk_mq_update_nr_hw_queues
 dev->nullb = NULL

Fix this problem by resuing the global mutex to protect
nullb_device_power_store() and nullb_update_nr_hw_queues() from configfs.

Fixes: 45919fbfe1c4 ("null_blk: Enable modifying 'submit_queues' after an instance has been configured")
Reported-and-tested-by: Yi Zhang 
Closes: https://lore.kernel.org/all/CAHj4cs9LgsHLnjg8z06LQ3Pr5cax-+Ps+xT7AP7TPnEjStuwZA@mail.gmail.com/
Signed-off-by: Yu Kuai 
Reviewed-by: Zhu Yanjun 
Link: https://lore.kernel.org/r/20240523153934.1937851-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe

null_blk: Fix two sparse warnings

2024-05-13T23:51:17+00:00

Fix the following sparse warnings:

drivers/block/null_blk/main.c:1243:35: warning: incorrect type in return expression (different base types)
drivers/block/null_blk/main.c:1243:35:    expected int
drivers/block/null_blk/main.c:1243:35:    got restricted blk_status_t
drivers/block/null_blk/main.c:1291:30: warning: incorrect type in return expression (different base types)
drivers/block/null_blk/main.c:1291:30:    expected restricted blk_status_t
drivers/block/null_blk/main.c:1291:30:    got int

Cc: Christoph Hellwig 
Cc: Damien Le Moal 
Signed-off-by: Bart Van Assche 
Link: https://lore.kernel.org/r/20240510201816.24921-1-bvanassche@acm.org
Signed-off-by: Jens Axboe

Merge tag 'for-6.10/block-20240511' of git://git.kernel.dk/linux

2024-05-13T20:03:54+00:00

Pull block updates from Jens Axboe:

 - Add a partscan attribute in sysfs, fixing an issue with systemd
   relying on an internal interface that went away.

 - Attempt #2 at making long running discards interruptible. The
   previous attempt went into 6.9, but we ended up mostly reverting it
   as it had issues.

 - Remove old ida_simple API in bcache

 - Support for zoned write plugging, greatly improving the performance
   on zoned devices.

 - Remove the old throttle low interface, which has been experimental
   since 2017 and never made it beyond that and isn't being used.

 - Remove page->index debugging checks in brd, as it hasn't caught
   anything and prepares us for removing in struct page.

 - MD pull request from Song

 - Don't schedule block workers on isolated CPUs

* tag 'for-6.10/block-20240511' of git://git.kernel.dk/linux: (84 commits)
  blk-throttle: delay initialization until configuration
  blk-throttle: remove CONFIG_BLK_DEV_THROTTLING_LOW
  block: fix that util can be greater than 100%
  block: support to account io_ticks precisely
  block: add plug while submitting IO
  bcache: fix variable length array abuse in btree_iter
  bcache: Remove usage of the deprecated ida_simple_xx() API
  md: Revert "md: Fix overflow in is_mddev_idle"
  blk-lib: check for kill signal in ioctl BLKDISCARD
  block: add a bio_await_chain helper
  block: add a blk_alloc_discard_bio helper
  block: add a bio_chain_and_submit helper
  block: move discard checks into the ioctl handler
  block: remove the discard_granularity check in __blkdev_issue_discard
  block/ioctl: prefer different overflow check
  null_blk: Fix the WARNING: modpost: missing MODULE_DESCRIPTION()
  block: fix and simplify blkdevparts= cmdline parsing
  block: refine the EOF check in blkdev_iomap_begin
  block: add a partscan sysfs attribute for disks
  block: add a disk_has_partscan helper
  ...

null_blk: Fix the WARNING: modpost: missing MODULE_DESCRIPTION()

2024-05-06T12:50:09+00:00

No functional changes intended.

Fixes: f2298c0403b0 ("null_blk: multi queue aware block test driver")
Signed-off-by: Zhu Yanjun 
Reviewed-by: Chaitanya Kulkarni 
Link: https://lore.kernel.org/r/20240506075538.6064-1-yanjun.zhu@linux.dev
Signed-off-by: Jens Axboe

null_blk: Fix missing mutex_destroy() at module removal

2024-04-25T20:15:00+00:00

When a mutex lock is not used any more, the function mutex_destroy
should be called to mark the mutex lock uninitialized.

Fixes: f2298c0403b0 ("null_blk: multi queue aware block test driver")
Signed-off-by: Zhu Yanjun 
Link: https://lore.kernel.org/r/20240425171635.4227-1-yanjun.zhu@linux.dev
Signed-off-by: Jens Axboe

null_blk: Simplify null_zone_write()

2024-04-17T14:44:07+00:00

In null_zone_write, we do not need to first check if the target zone
condition is FULL, READONLY or OFFLINE: for theses conditions, the check
of the command sector against the zone write pointer will always result
in the command failing. Remove these checks.

We still however need to check that the target zone write pointer is not
invalid for zone append operations. To do so, add the macro
NULL_ZONE_INVALID_WP and use it in null_set_zone_cond() when changing a
zone to READONLY or OFFLINE condition.

Signed-off-by: Damien Le Moal 
Reviewed-by: Johannes Thumshirn 
Link: https://lore.kernel.org/r/20240411085502.728558-4-dlemoal@kernel.org
Signed-off-by: Jens Axboe