<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/block/drbd, branch v5.4.232</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>drbd: use after free in drbd_create_device()</title>
<updated>2022-11-25T16:42:16+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>error27@gmail.com</email>
</author>
<published>2022-11-15T13:16:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=813a8dd9c45fd46f5cbbfbedf0791afa7740ccf5'/>
<id>813a8dd9c45fd46f5cbbfbedf0791afa7740ccf5</id>
<content type='text'>
[ Upstream commit a7a1598189228b5007369a9622ccdf587be0730f ]

The drbd_destroy_connection() frees the "connection" so use the _safe()
iterator to prevent a use after free.

Fixes: b6f85ef9538b ("drbd: Iterate over all connections")
Signed-off-by: Dan Carpenter &lt;error27@gmail.com&gt;
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Link: https://lore.kernel.org/r/Y3Jd5iZRbNQ9w6gm@kili
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 a7a1598189228b5007369a9622ccdf587be0730f ]

The drbd_destroy_connection() frees the "connection" so use the _safe()
iterator to prevent a use after free.

Fixes: b6f85ef9538b ("drbd: Iterate over all connections")
Signed-off-by: Dan Carpenter &lt;error27@gmail.com&gt;
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Link: https://lore.kernel.org/r/Y3Jd5iZRbNQ9w6gm@kili
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>drbd: fix duplicate array initializer</title>
<updated>2022-06-14T16:11:33+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2022-04-06T19:07:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3caa2d7943cab38c3bd6439b37a1825befe462e7'/>
<id>3caa2d7943cab38c3bd6439b37a1825befe462e7</id>
<content type='text'>
[ Upstream commit 33cb0917bbe241dd17a2b87ead63514c1b7e5615 ]

There are two initializers for P_RETRY_WRITE:

drivers/block/drbd/drbd_main.c:3676:22: warning: initialized field overwritten [-Woverride-init]

Remove the first one since it was already ignored by the compiler
and reorder the list to match the enum definition. As P_ZEROES had
no entry, add that one instead.

Fixes: 036b17eaab93 ("drbd: Receiving part for the PROTOCOL_UPDATE packet")
Fixes: f31e583aa2c2 ("drbd: introduce P_ZEROES (REQ_OP_WRITE_ZEROES on the "wire")")
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Link: https://lore.kernel.org/r/20220406190715.1938174-2-christoph.boehmwalder@linbit.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 33cb0917bbe241dd17a2b87ead63514c1b7e5615 ]

There are two initializers for P_RETRY_WRITE:

drivers/block/drbd/drbd_main.c:3676:22: warning: initialized field overwritten [-Woverride-init]

Remove the first one since it was already ignored by the compiler
and reorder the list to match the enum definition. As P_ZEROES had
no entry, add that one instead.

Fixes: 036b17eaab93 ("drbd: Receiving part for the PROTOCOL_UPDATE packet")
Fixes: f31e583aa2c2 ("drbd: introduce P_ZEROES (REQ_OP_WRITE_ZEROES on the "wire")")
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Link: https://lore.kernel.org/r/20220406190715.1938174-2-christoph.boehmwalder@linbit.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>drbd: remove usage of list iterator variable after loop</title>
<updated>2022-05-25T07:14:32+00:00</updated>
<author>
<name>Jakob Koschel</name>
<email>jakobkoschel@gmail.com</email>
</author>
<published>2022-03-31T22:03:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=232128f6e60f37a98cd6566d6d9685f0d43d0b77'/>
<id>232128f6e60f37a98cd6566d6d9685f0d43d0b77</id>
<content type='text'>
[ Upstream commit 901aeda62efa21f2eae937bccb71b49ae531be06 ]

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to iterate through the list [1].

Since that variable should not be used past the loop iteration, a
separate variable is used to 'remember the current location within the
loop'.

To either continue iterating from that position or skip the iteration
(if the previous iteration was complete) list_prepare_entry() is used.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel &lt;jakobkoschel@gmail.com&gt;
Link: https://lore.kernel.org/r/20220331220349.885126-1-jakobkoschel@gmail.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 901aeda62efa21f2eae937bccb71b49ae531be06 ]

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to iterate through the list [1].

Since that variable should not be used past the loop iteration, a
separate variable is used to 'remember the current location within the
loop'.

To either continue iterating from that position or skip the iteration
(if the previous iteration was complete) list_prepare_entry() is used.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel &lt;jakobkoschel@gmail.com&gt;
Link: https://lore.kernel.org/r/20220331220349.885126-1-jakobkoschel@gmail.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: drbd: drbd_nl: Make conversion to 'enum drbd_ret_code' explicit</title>
<updated>2022-05-15T17:54:46+00:00</updated>
<author>
<name>Lee Jones</name>
<email>lee.jones@linaro.org</email>
</author>
<published>2021-03-12T10:55:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e6ff94d31c53c5e5ae7d909d44cbc55ecfe725ad'/>
<id>e6ff94d31c53c5e5ae7d909d44cbc55ecfe725ad</id>
<content type='text'>
commit 1f1e87b4dc4598eac57a69868534b92d65e47e82 upstream.

Fixes the following W=1 kernel build warning(s):

 from drivers/block/drbd/drbd_nl.c:24:
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_set_role’:
 drivers/block/drbd/drbd_nl.c:793:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c:795:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_attach’:
 drivers/block/drbd/drbd_nl.c:1965:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_connect’:
 drivers/block/drbd/drbd_nl.c:2690:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_disconnect’:
 drivers/block/drbd/drbd_nl.c:2803:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]

Cc: Philipp Reisner &lt;philipp.reisner@linbit.com&gt;
Cc: Lars Ellenberg &lt;lars.ellenberg@linbit.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Link: https://lore.kernel.org/r/20210312105530.2219008-8-lee.jones@linaro.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 1f1e87b4dc4598eac57a69868534b92d65e47e82 upstream.

Fixes the following W=1 kernel build warning(s):

 from drivers/block/drbd/drbd_nl.c:24:
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_set_role’:
 drivers/block/drbd/drbd_nl.c:793:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c:795:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_attach’:
 drivers/block/drbd/drbd_nl.c:1965:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_connect’:
 drivers/block/drbd/drbd_nl.c:2690:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_disconnect’:
 drivers/block/drbd/drbd_nl.c:2803:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]

Cc: Philipp Reisner &lt;philipp.reisner@linbit.com&gt;
Cc: Lars Ellenberg &lt;lars.ellenberg@linbit.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Link: https://lore.kernel.org/r/20210312105530.2219008-8-lee.jones@linaro.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drbd: Fix five use after free bugs in get_initial_state</title>
<updated>2022-04-15T12:18:38+00:00</updated>
<author>
<name>Lv Yunlong</name>
<email>lyl2019@mail.ustc.edu.cn</email>
</author>
<published>2022-04-06T19:04:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b6a4055036eed1f5e239ce3d8b0db1ce38bba447'/>
<id>b6a4055036eed1f5e239ce3d8b0db1ce38bba447</id>
<content type='text'>
[ Upstream commit aadb22ba2f656581b2f733deb3a467c48cc618f6 ]

In get_initial_state, it calls notify_initial_state_done(skb,..) if
cb-&gt;args[5]==1. If genlmsg_put() failed in notify_initial_state_done(),
the skb will be freed by nlmsg_free(skb).
Then get_initial_state will goto out and the freed skb will be used by
return value skb-&gt;len, which is a uaf bug.

What's worse, the same problem goes even further: skb can also be
freed in the notify_*_state_change -&gt; notify_*_state calls below.
Thus 4 additional uaf bugs happened.

My patch lets the problem callee functions: notify_initial_state_done
and notify_*_state_change return an error code if errors happen.
So that the error codes could be propagated and the uaf bugs can be avoid.

v2 reports a compilation warning. This v3 fixed this warning and built
successfully in my local environment with no additional warnings.
v2: https://lore.kernel.org/patchwork/patch/1435218/

Fixes: a29728463b254 ("drbd: Backport the "events2" command")
Signed-off-by: Lv Yunlong &lt;lyl2019@mail.ustc.edu.cn&gt;
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
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 aadb22ba2f656581b2f733deb3a467c48cc618f6 ]

In get_initial_state, it calls notify_initial_state_done(skb,..) if
cb-&gt;args[5]==1. If genlmsg_put() failed in notify_initial_state_done(),
the skb will be freed by nlmsg_free(skb).
Then get_initial_state will goto out and the freed skb will be used by
return value skb-&gt;len, which is a uaf bug.

What's worse, the same problem goes even further: skb can also be
freed in the notify_*_state_change -&gt; notify_*_state calls below.
Thus 4 additional uaf bugs happened.

My patch lets the problem callee functions: notify_initial_state_done
and notify_*_state_change return an error code if errors happen.
So that the error codes could be propagated and the uaf bugs can be avoid.

v2 reports a compilation warning. This v3 fixed this warning and built
successfully in my local environment with no additional warnings.
v2: https://lore.kernel.org/patchwork/patch/1435218/

Fixes: a29728463b254 ("drbd: Backport the "events2" command")
Signed-off-by: Lv Yunlong &lt;lyl2019@mail.ustc.edu.cn&gt;
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
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>drbd: fix potential silent data corruption</title>
<updated>2022-04-15T12:18:01+00:00</updated>
<author>
<name>Lars Ellenberg</name>
<email>lars.ellenberg@linbit.com</email>
</author>
<published>2022-03-30T18:55:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ded62776302663332a1e7a561649cfb39632cb72'/>
<id>ded62776302663332a1e7a561649cfb39632cb72</id>
<content type='text'>
commit f4329d1f848ac35757d9cc5487669d19dfc5979c upstream.

Scenario:
---------

bio chain generated by blk_queue_split().
Some split bio fails and propagates its error status to the "parent" bio.
But then the (last part of the) parent bio itself completes without error.

We would clobber the already recorded error status with BLK_STS_OK,
causing silent data corruption.

Reproducer:
-----------

How to trigger this in the real world within seconds:

DRBD on top of degraded parity raid,
small stripe_cache_size, large read_ahead setting.
Drop page cache (sysctl vm.drop_caches=1, fadvise "DONTNEED",
umount and mount again, "reboot").

Cause significant read ahead.

Large read ahead request is split by blk_queue_split().
Parts of the read ahead that are already in the stripe cache,
or find an available stripe cache to use, can be serviced.
Parts of the read ahead that would need "too much work",
would need to wait for a "stripe_head" to become available,
are rejected immediately.

For larger read ahead requests that are split in many pieces, it is very
likely that some "splits" will be serviced, but then the stripe cache is
exhausted/busy, and the remaining ones will be rejected.

Signed-off-by: Lars Ellenberg &lt;lars.ellenberg@linbit.com&gt;
Signed-off-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.13.x
Link: https://lore.kernel.org/r/20220330185551.3553196-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f4329d1f848ac35757d9cc5487669d19dfc5979c upstream.

Scenario:
---------

bio chain generated by blk_queue_split().
Some split bio fails and propagates its error status to the "parent" bio.
But then the (last part of the) parent bio itself completes without error.

We would clobber the already recorded error status with BLK_STS_OK,
causing silent data corruption.

Reproducer:
-----------

How to trigger this in the real world within seconds:

DRBD on top of degraded parity raid,
small stripe_cache_size, large read_ahead setting.
Drop page cache (sysctl vm.drop_caches=1, fadvise "DONTNEED",
umount and mount again, "reboot").

Cause significant read ahead.

Large read ahead request is split by blk_queue_split().
Parts of the read ahead that are already in the stripe cache,
or find an available stripe cache to use, can be serviced.
Parts of the read ahead that would need "too much work",
would need to wait for a "stripe_head" to become available,
are rejected immediately.

For larger read ahead requests that are split in many pieces, it is very
likely that some "splits" will be serviced, but then the stripe cache is
exhausted/busy, and the remaining ones will be rejected.

Signed-off-by: Lars Ellenberg &lt;lars.ellenberg@linbit.com&gt;
Signed-off-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.13.x
Link: https://lore.kernel.org/r/20220330185551.3553196-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: drbd: remove a stray unlock in __drbd_send_protocol()</title>
<updated>2019-11-08T13:55:22+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2019-11-07T07:48:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8e9c523016cf9983b295e4bc659183d1fa6ef8e0'/>
<id>8e9c523016cf9983b295e4bc659183d1fa6ef8e0</id>
<content type='text'>
There are two callers of this function and they both unlock the mutex so
this ends up being a double unlock.

Fixes: 44ed167da748 ("drbd: rcu_read_lock() and rcu_dereference() for tconn-&gt;net_conf")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There are two callers of this function and they both unlock the mutex so
this ends up being a double unlock.

Fixes: 44ed167da748 ("drbd: rcu_read_lock() and rcu_dereference() for tconn-&gt;net_conf")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>augmented rbtree: add new RB_DECLARE_CALLBACKS_MAX macro</title>
<updated>2019-09-26T00:51:39+00:00</updated>
<author>
<name>Michel Lespinasse</name>
<email>walken@google.com</email>
</author>
<published>2019-09-25T23:46:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=315cc066b8ae8349a27887ad7a34e1916e9797fe'/>
<id>315cc066b8ae8349a27887ad7a34e1916e9797fe</id>
<content type='text'>
Add RB_DECLARE_CALLBACKS_MAX, which generates augmented rbtree callbacks
for the case where the augmented value is a scalar whose definition
follows a max(f(node)) pattern.  This actually covers all present uses of
RB_DECLARE_CALLBACKS, and saves some (source) code duplication in the
various RBCOMPUTE function definitions.

[walken@google.com: fix mm/vmalloc.c]
  Link: http://lkml.kernel.org/r/CANN689FXgK13wDYNh1zKxdipeTuALG4eKvKpsdZqKFJ-rvtGiQ@mail.gmail.com
[walken@google.com: re-add check to check_augmented()]
  Link: http://lkml.kernel.org/r/20190727022027.GA86863@google.com
Link: http://lkml.kernel.org/r/20190703040156.56953-3-walken@google.com
Signed-off-by: Michel Lespinasse &lt;walken@google.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Uladzislau Rezki &lt;urezki@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add RB_DECLARE_CALLBACKS_MAX, which generates augmented rbtree callbacks
for the case where the augmented value is a scalar whose definition
follows a max(f(node)) pattern.  This actually covers all present uses of
RB_DECLARE_CALLBACKS, and saves some (source) code duplication in the
various RBCOMPUTE function definitions.

[walken@google.com: fix mm/vmalloc.c]
  Link: http://lkml.kernel.org/r/CANN689FXgK13wDYNh1zKxdipeTuALG4eKvKpsdZqKFJ-rvtGiQ@mail.gmail.com
[walken@google.com: re-add check to check_augmented()]
  Link: http://lkml.kernel.org/r/20190727022027.GA86863@google.com
Link: http://lkml.kernel.org/r/20190703040156.56953-3-walken@google.com
Signed-off-by: Michel Lespinasse &lt;walken@google.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Uladzislau Rezki &lt;urezki@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>signal: Allow cifs and drbd to receive their terminating signals</title>
<updated>2019-08-19T11:34:13+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2019-08-16T17:33:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=33da8e7c814f77310250bb54a9db36a44c5de784'/>
<id>33da8e7c814f77310250bb54a9db36a44c5de784</id>
<content type='text'>
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd.  I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN.  So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.

Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig.  As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL.  Which after the first signal will allow userspace
to send signals to these kernel threads.  At least for
wake_ack_receiver in drbd that does not appear actively wrong.

So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.

Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.

This change was partly inspired by similar cifs and drbd patches that
added allow_signal.

Reported-by: ronnie sahlberg &lt;ronniesahlberg@gmail.com&gt;
Reported-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Tested-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Cc: Steve French &lt;smfrench@gmail.com&gt;
Cc: Philipp Reisner &lt;philipp.reisner@linbit.com&gt;
Cc: David Laight &lt;David.Laight@ACULAB.COM&gt;
Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd.  I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN.  So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.

Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig.  As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL.  Which after the first signal will allow userspace
to send signals to these kernel threads.  At least for
wake_ack_receiver in drbd that does not appear actively wrong.

So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.

Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.

This change was partly inspired by similar cifs and drbd patches that
added allow_signal.

Reported-by: ronnie sahlberg &lt;ronniesahlberg@gmail.com&gt;
Reported-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Tested-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt;
Cc: Steve French &lt;smfrench@gmail.com&gt;
Cc: Philipp Reisner &lt;philipp.reisner@linbit.com&gt;
Cc: David Laight &lt;David.Laight@ACULAB.COM&gt;
Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drbd: dynamically allocate shash descriptor</title>
<updated>2019-07-23T13:35:18+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2019-07-22T12:26:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=77ce56e2bfaa64127ae5e23ef136c0168b818777'/>
<id>77ce56e2bfaa64127ae5e23ef136c0168b818777</id>
<content type='text'>
Building with clang and KASAN, we get a warning about an overly large
stack frame on 32-bit architectures:

drivers/block/drbd/drbd_receiver.c:921:31: error: stack frame size of 1280 bytes in function 'conn_connect'
      [-Werror,-Wframe-larger-than=]

We already allocate other data dynamically in this function, so
just do the same for the shash descriptor, which makes up most of
this memory.

Link: https://lore.kernel.org/lkml/20190617132440.2721536-1-arnd@arndb.de/
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Roland Kammerer &lt;roland.kammerer@linbit.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Building with clang and KASAN, we get a warning about an overly large
stack frame on 32-bit architectures:

drivers/block/drbd/drbd_receiver.c:921:31: error: stack frame size of 1280 bytes in function 'conn_connect'
      [-Werror,-Wframe-larger-than=]

We already allocate other data dynamically in this function, so
just do the same for the shash descriptor, which makes up most of
this memory.

Link: https://lore.kernel.org/lkml/20190617132440.2721536-1-arnd@arndb.de/
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Roland Kammerer &lt;roland.kammerer@linbit.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
</feed>
