<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/block, branch v6.13.9</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>block: change blk_mq_add_to_batch() third argument type to bool</title>
<updated>2025-03-22T19:56:57+00:00</updated>
<author>
<name>Shin'ichiro Kawasaki</name>
<email>shinichiro.kawasaki@wdc.com</email>
</author>
<published>2025-03-11T10:43:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7612ae9b278ce6782a55fcdb7f556fedc219194a'/>
<id>7612ae9b278ce6782a55fcdb7f556fedc219194a</id>
<content type='text'>
[ Upstream commit 9bce6b5f8987678b9c6c1fe433af6b5fe41feadc ]

Commit 1f47ed294a2b ("block: cleanup and fix batch completion adding
conditions") modified the evaluation criteria for the third argument,
'ioerror', in the blk_mq_add_to_batch() function. Initially, the
function had checked if 'ioerror' equals zero. Following the commit, it
started checking for negative error values, with the presumption that
such values, for instance -EIO, would be passed in.

However, blk_mq_add_to_batch() callers do not pass negative error
values. Instead, they pass status codes defined in various ways:

- NVMe PCI and Apple drivers pass NVMe status code
- virtio_blk driver passes the virtblk request header status byte
- null_blk driver passes blk_status_t

These codes are either zero or positive, therefore the revised check
fails to function as intended. Specifically, with the NVMe PCI driver,
this modification led to the failure of the blktests test case nvme/039.
In this test scenario, errors are artificially injected to the NVMe
driver, resulting in positive NVMe status codes passed to
blk_mq_add_to_batch(), which unexpectedly processes the failed I/O in a
batch. Hence the failure.

To correct the ioerror check within blk_mq_add_to_batch(), make all
callers to uniformly pass the argument as boolean. Modify the callers to
check their specific status codes and pass the boolean value 'is_error'.
Also describe the arguments of blK_mq_add_to_batch as kerneldoc.

Fixes: 1f47ed294a2b ("block: cleanup and fix batch completion adding conditions")
Signed-off-by: Shin'ichiro Kawasaki &lt;shinichiro.kawasaki@wdc.com&gt;
Link: https://lore.kernel.org/r/20250311104359.1767728-3-shinichiro.kawasaki@wdc.com
[axboe: fold in documentation update]
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9bce6b5f8987678b9c6c1fe433af6b5fe41feadc ]

Commit 1f47ed294a2b ("block: cleanup and fix batch completion adding
conditions") modified the evaluation criteria for the third argument,
'ioerror', in the blk_mq_add_to_batch() function. Initially, the
function had checked if 'ioerror' equals zero. Following the commit, it
started checking for negative error values, with the presumption that
such values, for instance -EIO, would be passed in.

However, blk_mq_add_to_batch() callers do not pass negative error
values. Instead, they pass status codes defined in various ways:

- NVMe PCI and Apple drivers pass NVMe status code
- virtio_blk driver passes the virtblk request header status byte
- null_blk driver passes blk_status_t

These codes are either zero or positive, therefore the revised check
fails to function as intended. Specifically, with the NVMe PCI driver,
this modification led to the failure of the blktests test case nvme/039.
In this test scenario, errors are artificially injected to the NVMe
driver, resulting in positive NVMe status codes passed to
blk_mq_add_to_batch(), which unexpectedly processes the failed I/O in a
batch. Hence the failure.

To correct the ioerror check within blk_mq_add_to_batch(), make all
callers to uniformly pass the argument as boolean. Modify the callers to
check their specific status codes and pass the boolean value 'is_error'.
Also describe the arguments of blK_mq_add_to_batch as kerneldoc.

Fixes: 1f47ed294a2b ("block: cleanup and fix batch completion adding conditions")
Signed-off-by: Shin'ichiro Kawasaki &lt;shinichiro.kawasaki@wdc.com&gt;
Link: https://lore.kernel.org/r/20250311104359.1767728-3-shinichiro.kawasaki@wdc.com
[axboe: fold in documentation update]
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ublk: set_params: properly check if parameters can be applied</title>
<updated>2025-03-13T12:07:58+00:00</updated>
<author>
<name>Uday Shankar</name>
<email>ushankar@purestorage.com</email>
</author>
<published>2025-03-04T21:34:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1eb71084e542b1e64feb4d7022a57d378e380ca9'/>
<id>1eb71084e542b1e64feb4d7022a57d378e380ca9</id>
<content type='text'>
[ Upstream commit 5ac60242b0173be83709603ebaf27a473f16c4e4 ]

The parameters set by the set_params call are only applied to the block
device in the start_dev call. So if a device has already been started, a
subsequently issued set_params on that device will not have the desired
effect, and should return an error. There is an existing check for this
- set_params fails on devices in the LIVE state. But this check is not
sufficient to cover the recovery case. In this case, the device will be
in the QUIESCED or FAIL_IO states, so set_params will succeed. But this
success is misleading, because the parameters will not be applied, since
the device has already been started (by a previous ublk server). The bit
UB_STATE_USED is set on completion of the start_dev; use it to detect
and fail set_params commands which arrive too late to be applied (after
start_dev).

Signed-off-by: Uday Shankar &lt;ushankar@purestorage.com&gt;
Fixes: 0aa73170eba5 ("ublk_drv: add SET_PARAMS/GET_PARAMS control command")
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Link: https://lore.kernel.org/r/20250304-set_params-v1-1-17b5e0887606@purestorage.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 5ac60242b0173be83709603ebaf27a473f16c4e4 ]

The parameters set by the set_params call are only applied to the block
device in the start_dev call. So if a device has already been started, a
subsequently issued set_params on that device will not have the desired
effect, and should return an error. There is an existing check for this
- set_params fails on devices in the LIVE state. But this check is not
sufficient to cover the recovery case. In this case, the device will be
in the QUIESCED or FAIL_IO states, so set_params will succeed. But this
success is misleading, because the parameters will not be applied, since
the device has already been started (by a previous ublk server). The bit
UB_STATE_USED is set on completion of the start_dev; use it to detect
and fail set_params commands which arrive too late to be applied (after
start_dev).

Signed-off-by: Uday Shankar &lt;ushankar@purestorage.com&gt;
Fixes: 0aa73170eba5 ("ublk_drv: add SET_PARAMS/GET_PARAMS control command")
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Link: https://lore.kernel.org/r/20250304-set_params-v1-1-17b5e0887606@purestorage.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: add a queue_limits_commit_update_frozen helper</title>
<updated>2025-02-08T09:00:55+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2025-01-10T05:47:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=12b32e80a5cde170b8ccaf435288c4c47e5ff95c'/>
<id>12b32e80a5cde170b8ccaf435288c4c47e5ff95c</id>
<content type='text'>
[ Upstream commit aa427d7b73b196f657d6d2cf0e94eff6b883fdef ]

Add a helper that freezes the queue, updates the queue limits and
unfreezes the queue and convert all open coded versions of that to the
new helper.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: John Garry &lt;john.g.garry@oracle.com&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Reviewed-by: Nilay Shroff &lt;nilay@linux.ibm.com&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Link: https://lore.kernel.org/r/20250110054726.1499538-3-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Stable-dep-of: c99f66e4084a ("block: fix queue freeze vs limits lock order in sysfs store methods")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit aa427d7b73b196f657d6d2cf0e94eff6b883fdef ]

Add a helper that freezes the queue, updates the queue limits and
unfreezes the queue and convert all open coded versions of that to the
new helper.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: John Garry &lt;john.g.garry@oracle.com&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Reviewed-by: Nilay Shroff &lt;nilay@linux.ibm.com&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Link: https://lore.kernel.org/r/20250110054726.1499538-3-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Stable-dep-of: c99f66e4084a ("block: fix queue freeze vs limits lock order in sysfs store methods")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nbd: don't allow reconnect after disconnect</title>
<updated>2025-02-08T09:00:54+00:00</updated>
<author>
<name>Yu Kuai</name>
<email>yukuai3@huawei.com</email>
</author>
<published>2025-01-03T09:28:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9793bd5ae4bdbdb2dde401a3cab94a6bfd05e302'/>
<id>9793bd5ae4bdbdb2dde401a3cab94a6bfd05e302</id>
<content type='text'>
[ 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-&gt;recv_workq)
    if (test_and_clear_bit(NBD_RT_HAS_CONFIG_REF, ...))
     nbd_config_put
     -&gt; 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)
   -&gt; succeed
   if (!test_bit(NBD_RT_BOUND, ...))
   -&gt; succeed
   nbd_reconnect_socket
    queue_work(nbd-&gt;recv_workq, &amp;args-&gt;work)

4) step 1) release the reference;

5) Finially, recv_work() will trigger UAF:

  recv_work
   nbd_config_put(nbd)
   -&gt; nbd_config is freed
   atomic_dec(&amp;config-&gt;recv_threads)
   -&gt; 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 &lt;yukuai3@huawei.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/20250103092859.3574648-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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-&gt;recv_workq)
    if (test_and_clear_bit(NBD_RT_HAS_CONFIG_REF, ...))
     nbd_config_put
     -&gt; 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)
   -&gt; succeed
   if (!test_bit(NBD_RT_BOUND, ...))
   -&gt; succeed
   nbd_reconnect_socket
    queue_work(nbd-&gt;recv_workq, &amp;args-&gt;work)

4) step 1) release the reference;

5) Finially, recv_work() will trigger UAF:

  recv_work
   nbd_config_put(nbd)
   -&gt; nbd_config is freed
   atomic_dec(&amp;config-&gt;recv_threads)
   -&gt; 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 &lt;yukuai3@huawei.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/20250103092859.3574648-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ps3disk: Do not use dev-&gt;bounce_size before it is set</title>
<updated>2025-02-08T09:00:54+00:00</updated>
<author>
<name>Geert Uytterhoeven</name>
<email>geert+renesas@glider.be</email>
</author>
<published>2025-01-03T08:51:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3b5acd5e5fb99fb6654ea5034b824f2a10b00aea'/>
<id>3b5acd5e5fb99fb6654ea5034b824f2a10b00aea</id>
<content type='text'>
[ Upstream commit c2398e6d5f16e15598d3a37e17107fea477e3f91 ]

dev-&gt;bounce_size is only initialized after it is used to set the queue
limits.  Fix this by using BOUNCE_SIZE instead.

Fixes: a7f18b74dbe17162 ("ps3disk: pass queue_limits to blk_mq_alloc_disk")
Reported-by: Philipp Hortmann &lt;philipp.g.hortmann@gmail.com&gt;
Closes: https://lore.kernel.org/39256db9-3d73-4e86-a49b-300dfd670212@gmail.com
Signed-off-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/06988f959ea6885b8bd7fb3b9059dd54bc6bbad7.1735894216.git.geert+renesas@glider.be
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c2398e6d5f16e15598d3a37e17107fea477e3f91 ]

dev-&gt;bounce_size is only initialized after it is used to set the queue
limits.  Fix this by using BOUNCE_SIZE instead.

Fixes: a7f18b74dbe17162 ("ps3disk: pass queue_limits to blk_mq_alloc_disk")
Reported-by: Philipp Hortmann &lt;philipp.g.hortmann@gmail.com&gt;
Closes: https://lore.kernel.org/39256db9-3d73-4e86-a49b-300dfd670212@gmail.com
Signed-off-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/06988f959ea6885b8bd7fb3b9059dd54bc6bbad7.1735894216.git.geert+renesas@glider.be
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: fix potential UAF of zram table</title>
<updated>2025-01-13T03:03:37+00:00</updated>
<author>
<name>Kairui Song</name>
<email>kasong@tencent.com</email>
</author>
<published>2025-01-07T06:54:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=212fe1c0df4a150fb6298db2cfff267ceaba5402'/>
<id>212fe1c0df4a150fb6298db2cfff267ceaba5402</id>
<content type='text'>
If zram_meta_alloc failed early, it frees allocated zram-&gt;table without
setting it NULL.  Which will potentially cause zram_meta_free to access
the table if user reset an failed and uninitialized device.

Link: https://lkml.kernel.org/r/20250107065446.86928-1-ryncsn@gmail.com
Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Signed-off-by: Kairui Song &lt;kasong@tencent.com&gt;
Reviewed-by:  Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If zram_meta_alloc failed early, it frees allocated zram-&gt;table without
setting it NULL.  Which will potentially cause zram_meta_free to access
the table if user reset an failed and uninitialized device.

Link: https://lkml.kernel.org/r/20250107065446.86928-1-ryncsn@gmail.com
Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Signed-off-by: Kairui Song &lt;kasong@tencent.com&gt;
Reviewed-by:  Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'block-6.13-20241228' of git://git.kernel.dk/linux</title>
<updated>2024-12-28T19:02:35+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-12-28T19:02:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=059dd502b263d8a4e2a84809cf1068d6a3905e6f'/>
<id>059dd502b263d8a4e2a84809cf1068d6a3905e6f</id>
<content type='text'>
Pull block fix from Jens Axboe:
 "Just a single fix for ublk setup error handling"

* tag 'block-6.13-20241228' of git://git.kernel.dk/linux:
  ublk: detach gendisk from ublk device if add_disk() fails
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull block fix from Jens Axboe:
 "Just a single fix for ublk setup error handling"

* tag 'block-6.13-20241228' of git://git.kernel.dk/linux:
  ublk: detach gendisk from ublk device if add_disk() fails
</pre>
</div>
</content>
</entry>
<entry>
<title>ublk: detach gendisk from ublk device if add_disk() fails</title>
<updated>2024-12-26T13:42:55+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@redhat.com</email>
</author>
<published>2024-12-25T11:06:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=75cd4005da5492129917a4a4ee45e81660556104'/>
<id>75cd4005da5492129917a4a4ee45e81660556104</id>
<content type='text'>
Inside ublk_abort_requests(), gendisk is grabbed for aborting all
inflight requests. And ublk_abort_requests() is called when exiting
the uring context or handling timeout.

If add_disk() fails, the gendisk may have been freed when calling
ublk_abort_requests(), so use-after-free can be caused when getting
disk's reference in ublk_abort_requests().

Fixes the bug by detaching gendisk from ublk device if add_disk() fails.

Fixes: bd23f6c2c2d0 ("ublk: quiesce request queue when aborting queue")
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Link: https://lore.kernel.org/r/20241225110640.351531-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Inside ublk_abort_requests(), gendisk is grabbed for aborting all
inflight requests. And ublk_abort_requests() is called when exiting
the uring context or handling timeout.

If add_disk() fails, the gendisk may have been freed when calling
ublk_abort_requests(), so use-after-free can be caused when getting
disk's reference in ublk_abort_requests().

Fixes the bug by detaching gendisk from ublk device if add_disk() fails.

Fixes: bd23f6c2c2d0 ("ublk: quiesce request queue when aborting queue")
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Link: https://lore.kernel.org/r/20241225110640.351531-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: fix uninitialized ZRAM not releasing backing device</title>
<updated>2024-12-19T03:04:44+00:00</updated>
<author>
<name>Kairui Song</name>
<email>kasong@tencent.com</email>
</author>
<published>2024-12-09T16:57:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=74363ec674cb172d8856de25776c8f3103f05e2f'/>
<id>74363ec674cb172d8856de25776c8f3103f05e2f</id>
<content type='text'>
Setting backing device is done before ZRAM initialization.  If we set the
backing device, then remove the ZRAM module without initializing the
device, the backing device reference will be leaked and the device will be
hold forever.

Fix this by always reset the ZRAM fully on rmmod or reset store.

Link: https://lkml.kernel.org/r/20241209165717.94215-3-ryncsn@gmail.com
Fixes: 013bf95a83ec ("zram: add interface to specif backing device")
Signed-off-by: Kairui Song &lt;kasong@tencent.com&gt;
Reported-by: Desheng Wu &lt;deshengwu@tencent.com&gt;
Suggested-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Reviewed-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Setting backing device is done before ZRAM initialization.  If we set the
backing device, then remove the ZRAM module without initializing the
device, the backing device reference will be leaked and the device will be
hold forever.

Fix this by always reset the ZRAM fully on rmmod or reset store.

Link: https://lkml.kernel.org/r/20241209165717.94215-3-ryncsn@gmail.com
Fixes: 013bf95a83ec ("zram: add interface to specif backing device")
Signed-off-by: Kairui Song &lt;kasong@tencent.com&gt;
Reported-by: Desheng Wu &lt;deshengwu@tencent.com&gt;
Suggested-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Reviewed-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: refuse to use zero sized block device as backing device</title>
<updated>2024-12-19T03:04:44+00:00</updated>
<author>
<name>Kairui Song</name>
<email>kasong@tencent.com</email>
</author>
<published>2024-12-09T16:57:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=be48c412f6ebf38849213c19547bc6d5b692b5e5'/>
<id>be48c412f6ebf38849213c19547bc6d5b692b5e5</id>
<content type='text'>
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 &gt; /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 &lt;kasong@tencent.com&gt;
Reported-by: Desheng Wu &lt;deshengwu@tencent.com&gt;
Reviewed-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &gt; /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 &lt;kasong@tencent.com&gt;
Reported-by: Desheng Wu &lt;deshengwu@tencent.com&gt;
Reviewed-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
