linux-stable.git/drivers/block, branch v5.10.243

drbd: add missing kref_get in handle_write_conflicts

2025-08-28T14:22:39+00:00

[ Upstream commit 00c9c9628b49e368d140cfa61d7df9b8922ec2a8 ]

With `two-primaries` enabled, DRBD tries to detect "concurrent" writes
and handle write conflicts, so that even if you write to the same sector
simultaneously on both nodes, they end up with the identical data once
the writes are completed.

In handling "superseeded" writes, we forgot a kref_get,
resulting in a premature drbd_destroy_device and use after free,
and further to kernel crashes with symptoms.

Relevance: No one should use DRBD as a random data generator, and apparently
all users of "two-primaries" handle concurrent writes correctly on layer up.
That is cluster file systems use some distributed lock manager,
and live migration in virtualization environments stops writes on one node
before starting writes on the other node.

Which means that other than for "test cases",
this code path is never taken in real life.

FYI, in DRBD 9, things are handled differently nowadays.  We still detect
"write conflicts", but no longer try to be smart about them.
We decided to disconnect hard instead: upper layers must not submit concurrent
writes. If they do, that's their fault.

Signed-off-by: Sarah Newman 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Christoph Böhmwalder 
Link: https://lore.kernel.org/r/20250627095728.800688-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

sunvdc: Balance device refcount in vdc_port_mpgroup_check

2025-08-28T14:22:38+00:00

commit 63ce53724637e2e7ba51fe3a4f78351715049905 upstream.

Using device_find_child() to locate a probed virtual-device-port node
causes a device refcount imbalance, as device_find_child() internally
calls get_device() to increment the device’s reference count before
returning its pointer. vdc_port_mpgroup_check() directly returns true
upon finding a matching device without releasing the reference via
put_device(). We should call put_device() to decrement refcount.

As comment of device_find_child() says, 'NOTE: you will need to drop
the reference with put_device() after use'.

Found by code review.

Cc: stable@vger.kernel.org
Fixes: 3ee70591d6c4 ("sunvdc: prevent sunvdc panic when mpgroup disk added to guest domain")
Signed-off-by: Ma Ke 
Link: https://lore.kernel.org/r/20250719075856.3447953-1-make24@iscas.ac.cn
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

aoe: clean device rq_list in aoedev_downdev()

2025-06-27T10:04:22+00:00

[ Upstream commit 7f90d45e57cb2ef1f0adcaf925ddffdfc5e680ca ]

An aoe device's rq_list contains accepted block requests that are
waiting to be transmitted to the aoe target. This queue was added as
part of the conversion to blk_mq. However, the queue was not cleaned out
when an aoe device is downed which caused blk_mq_freeze_queue() to sleep
indefinitely waiting for those requests to complete, causing a hang. This
fix cleans out the queue before calling blk_mq_freeze_queue().

Link: https://bugzilla.kernel.org/show_bug.cgi?id=212665
Fixes: 3582dd291788 ("aoe: convert aoeblk to blk-mq")
Signed-off-by: Justin Sanders 
Link: https://lore.kernel.org/r/20250610170600.869-1-jsanders.devel@gmail.com
Tested-By: Valentin Kleibel 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

nbd: don't allow reconnect after disconnect

2025-03-13T11:46:44+00:00

[ Upstream commit 844b8cdc681612ff24df62cdefddeab5772fadf1 ]

Following process can cause nbd_config UAF:

1) grab nbd_config temporarily;

2) nbd_genl_disconnect() flush all recv_work() and release the
initial reference:

  nbd_genl_disconnect
   nbd_disconnect_and_put
    nbd_disconnect
     flush_workqueue(nbd->recv_workq)
    if (test_and_clear_bit(NBD_RT_HAS_CONFIG_REF, ...))
     nbd_config_put
     -> due to step 1), reference is still not zero

3) nbd_genl_reconfigure() queue recv_work() again;

  nbd_genl_reconfigure
   config = nbd_get_config_unlocked(nbd)
   if (!config)
   -> succeed
   if (!test_bit(NBD_RT_BOUND, ...))
   -> succeed
   nbd_reconnect_socket
    queue_work(nbd->recv_workq, &args->work)

4) step 1) release the reference;

5) Finially, recv_work() will trigger UAF:

  recv_work
   nbd_config_put(nbd)
   -> nbd_config is freed
   atomic_dec(&config->recv_threads)
   -> UAF

Fix the problem by clearing NBD_RT_BOUND in nbd_genl_disconnect(), so
that nbd_genl_reconfigure() will fail.

Fixes: b7aa3d39385d ("nbd: add a reconfigure netlink command")
Reported-by: syzbot+6b0df248918b92c33e6a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/675bfb65.050a0220.1a2d0d.0006.GAE@google.com/
Signed-off-by: Yu Kuai 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20250103092859.3574648-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block: remove the update_bdev parameter to set_capacity_revalidate_and_notify

2025-02-01T17:22:24+00:00

[ Upstream commit 449f4ec9892ebc2f37a7eae6d97db2cf7c65e09a ]

The update_bdev argument is always set to true, so remove it.  Also
rename the function to the slighly less verbose set_capacity_and_notify,
as propagating the disk size to the block device isn't really
revalidation.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Petr Vorel 
Signed-off-by: Jens Axboe 
Stable-dep-of: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Signed-off-by: Sasha Levin

loop: let set_capacity_revalidate_and_notify update the bdev size

2025-02-01T17:22:24+00:00

[ Upstream commit 3b4f85d02a4bd85cbea999a064235a47694bbb7b ]

There is no good reason to call revalidate_disk_size separately.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe 
Stable-dep-of: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Signed-off-by: Sasha Levin

virtio-blk: don't keep queue frozen during system suspend

2025-01-09T12:24:58+00:00

[ Upstream commit 7678abee0867e6b7fb89aa40f6e9f575f755fb37 ]

Commit 4ce6e2db00de ("virtio-blk: Ensure no requests in virtqueues before
deleting vqs.") replaces queue quiesce with queue freeze in virtio-blk's
PM callbacks. And the motivation is to drain inflight IOs before suspending.

block layer's queue freeze looks very handy, but it is also easy to cause
deadlock, such as, any attempt to call into bio_queue_enter() may run into
deadlock if the queue is frozen in current context. There are all kinds
of ->suspend() called in suspend context, so keeping queue frozen in the
whole suspend context isn't one good idea. And Marek reported lockdep
warning[1] caused by virtio-blk's freeze queue in virtblk_freeze().

[1] https://lore.kernel.org/linux-block/ca16370e-d646-4eee-b9cc-87277c89c43c@samsung.com/

Given the motivation is to drain in-flight IOs, it can be done by calling
freeze & unfreeze, meantime restore to previous behavior by keeping queue
quiesced during suspend.

Cc: Yi Sun 
Cc: Michael S. Tsirkin 
Cc: Jason Wang 
Cc: Stefan Hajnoczi 
Cc: virtualization@lists.linux.dev
Reported-by: Marek Szyprowski 
Signed-off-by: Ming Lei 
Acked-by: Stefan Hajnoczi 
Link: https://lore.kernel.org/r/20241112125821.1475793-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

zram: refuse to use zero sized block device as backing device

2025-01-09T12:24:54+00:00

commit be48c412f6ebf38849213c19547bc6d5b692b5e5 upstream.

Patch series "zram: fix backing device setup issue", v2.

This series fixes two bugs of backing device setting:

- ZRAM should reject using a zero sized (or the uninitialized ZRAM
  device itself) as the backing device.
- Fix backing device leaking when removing a uninitialized ZRAM
  device.


This patch (of 2):

Setting a zero sized block device as backing device is pointless, and one
can easily create a recursive loop by setting the uninitialized ZRAM
device itself as its own backing device by (zram0 is uninitialized):

    echo /dev/zram0 > /sys/block/zram0/backing_dev

It's definitely a wrong config, and the module will pin itself, kernel
should refuse doing so in the first place.

By refusing to use zero sized device we avoided misuse cases including
this one above.

Link: https://lkml.kernel.org/r/20241209165717.94215-1-ryncsn@gmail.com
Link: https://lkml.kernel.org/r/20241209165717.94215-2-ryncsn@gmail.com
Fixes: 013bf95a83ec ("zram: add interface to specif backing device")
Signed-off-by: Kairui Song 
Reported-by: Desheng Wu 
Reviewed-by: Sergey Senozhatsky 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

aoe: fix the potential use-after-free problem in more places

2024-10-17T13:08:23+00:00

commit 6d6e54fc71ad1ab0a87047fd9c211e75d86084a3 upstream.

For fixing CVE-2023-6270, f98364e92662 ("aoe: fix the potential
use-after-free problem in aoecmd_cfg_pkts") makes tx() calling dev_put()
instead of doing in aoecmd_cfg_pkts(). It avoids that the tx() runs
into use-after-free.

Then Nicolai Stange found more places in aoe have potential use-after-free
problem with tx(). e.g. revalidate(), aoecmd_ata_rw(), resend(), probe()
and aoecmd_cfg_rsp(). Those functions also use aoenet_xmit() to push
packet to tx queue. So they should also use dev_hold() to increase the
refcnt of skb->dev.

On the other hand, moving dev_put() to tx() causes that the refcnt of
skb->dev be reduced to a negative value, because corresponding
dev_hold() are not called in revalidate(), aoecmd_ata_rw(), resend(),
probe(), and aoecmd_cfg_rsp(). This patch fixed this issue.

Cc: stable@vger.kernel.org
Link: https://nvd.nist.gov/vuln/detail/CVE-2023-6270
Fixes: f98364e92662 ("aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts")
Reported-by: Nicolai Stange 
Signed-off-by: Chun-Yi Lee 
Link: https://lore.kernel.org/stable/20240624064418.27043-1-jlee%40suse.com
Link: https://lore.kernel.org/r/20241002035458.24401-1-jlee@suse.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

drbd: Add NULL check for net_conf to prevent dereference in state validation

2024-10-17T13:08:01+00:00

commit a5e61b50c9f44c5edb6e134ede6fee8806ffafa9 upstream.

If the net_conf pointer is NULL and the code attempts to access its
fields without a check, it will lead to a null pointer dereference.
Add a NULL check before dereferencing the pointer.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 44ed167da748 ("drbd: rcu_read_lock() and rcu_dereference() for tconn->net_conf")
Cc: stable@vger.kernel.org
Signed-off-by: Mikhail Lobanov 
Link: https://lore.kernel.org/r/20240909133740.84297-1-m.lobanov@rosalinux.ru
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman