<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include, branch v4.4.249</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>xen/xenbus: Count pending messages for each watch</title>
<updated>2020-12-29T12:42:45+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sjpark@amazon.de</email>
</author>
<published>2020-12-14T09:07:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=df3367c1cb5e1a6d8a527d651f2163756c81c116'/>
<id>df3367c1cb5e1a6d8a527d651f2163756c81c116</id>
<content type='text'>
commit 3dc86ca6b4c8cfcba9da7996189d1b5a358a94fc upstream.

This commit adds a counter of pending messages for each watch in the
struct.  It is used to skip unnecessary pending messages lookup in
'unregister_xenbus_watch()'.  It could also be used in 'will_handle'
callback.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park &lt;sjpark@amazon.de&gt;
Reported-by: Michael Kurth &lt;mku@amazon.de&gt;
Reported-by: Pawel Wieczorkiewicz &lt;wipawel@amazon.de&gt;
Reviewed-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&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 3dc86ca6b4c8cfcba9da7996189d1b5a358a94fc upstream.

This commit adds a counter of pending messages for each watch in the
struct.  It is used to skip unnecessary pending messages lookup in
'unregister_xenbus_watch()'.  It could also be used in 'will_handle'
callback.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park &lt;sjpark@amazon.de&gt;
Reported-by: Michael Kurth &lt;mku@amazon.de&gt;
Reported-by: Pawel Wieczorkiewicz &lt;wipawel@amazon.de&gt;
Reviewed-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;


</pre>
</div>
</content>
</entry>
<entry>
<title>xen/xenbus: Add 'will_handle' callback support in xenbus_watch_path()</title>
<updated>2020-12-29T12:42:45+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sjpark@amazon.de</email>
</author>
<published>2020-12-14T09:04:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=aafb4352cba47df628649983d93d14dee5527f1d'/>
<id>aafb4352cba47df628649983d93d14dee5527f1d</id>
<content type='text'>
commit 2e85d32b1c865bec703ce0c962221a5e955c52c2 upstream.

Some code does not directly make 'xenbus_watch' object and call
'register_xenbus_watch()' but use 'xenbus_watch_path()' instead.  This
commit adds support of 'will_handle' callback in the
'xenbus_watch_path()' and it's wrapper, 'xenbus_watch_pathfmt()'.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park &lt;sjpark@amazon.de&gt;
Reported-by: Michael Kurth &lt;mku@amazon.de&gt;
Reported-by: Pawel Wieczorkiewicz &lt;wipawel@amazon.de&gt;
Reviewed-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&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 2e85d32b1c865bec703ce0c962221a5e955c52c2 upstream.

Some code does not directly make 'xenbus_watch' object and call
'register_xenbus_watch()' but use 'xenbus_watch_path()' instead.  This
commit adds support of 'will_handle' callback in the
'xenbus_watch_path()' and it's wrapper, 'xenbus_watch_pathfmt()'.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park &lt;sjpark@amazon.de&gt;
Reported-by: Michael Kurth &lt;mku@amazon.de&gt;
Reported-by: Pawel Wieczorkiewicz &lt;wipawel@amazon.de&gt;
Reviewed-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;


</pre>
</div>
</content>
</entry>
<entry>
<title>xen/xenbus: Allow watches discard events before queueing</title>
<updated>2020-12-29T12:42:45+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sjpark@amazon.de</email>
</author>
<published>2020-12-14T09:02:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=de66402f45c0cae9566b1568cc1b2df2b5ccbbf8'/>
<id>de66402f45c0cae9566b1568cc1b2df2b5ccbbf8</id>
<content type='text'>
commit fed1755b118147721f2c87b37b9d66e62c39b668 upstream.

If handling logics of watch events are slower than the events enqueue
logic and the events can be created from the guests, the guests could
trigger memory pressure by intensively inducing the events, because it
will create a huge number of pending events that exhausting the memory.

Fortunately, some watch events could be ignored, depending on its
handler callback.  For example, if the callback has interest in only one
single path, the watch wouldn't want multiple pending events.  Or, some
watches could ignore events to same path.

To let such watches to volutarily help avoiding the memory pressure
situation, this commit introduces new watch callback, 'will_handle'.  If
it is not NULL, it will be called for each new event just before
enqueuing it.  Then, if the callback returns false, the event will be
discarded.  No watch is using the callback for now, though.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park &lt;sjpark@amazon.de&gt;
Reported-by: Michael Kurth &lt;mku@amazon.de&gt;
Reported-by: Pawel Wieczorkiewicz &lt;wipawel@amazon.de&gt;
Reviewed-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&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 fed1755b118147721f2c87b37b9d66e62c39b668 upstream.

If handling logics of watch events are slower than the events enqueue
logic and the events can be created from the guests, the guests could
trigger memory pressure by intensively inducing the events, because it
will create a huge number of pending events that exhausting the memory.

Fortunately, some watch events could be ignored, depending on its
handler callback.  For example, if the callback has interest in only one
single path, the watch wouldn't want multiple pending events.  Or, some
watches could ignore events to same path.

To let such watches to volutarily help avoiding the memory pressure
situation, this commit introduces new watch callback, 'will_handle'.  If
it is not NULL, it will be called for each new event just before
enqueuing it.  Then, if the callback returns false, the event will be
discarded.  No watch is using the callback for now, though.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park &lt;sjpark@amazon.de&gt;
Reported-by: Michael Kurth &lt;mku@amazon.de&gt;
Reported-by: Pawel Wieczorkiewicz &lt;wipawel@amazon.de&gt;
Reviewed-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;


</pre>
</div>
</content>
</entry>
<entry>
<title>seq_buf: Avoid type mismatch for seq_buf_init</title>
<updated>2020-12-29T12:42:39+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2020-10-26T16:10:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1e3a40233d04879b54093e107f9af4195c4cfec3'/>
<id>1e3a40233d04879b54093e107f9af4195c4cfec3</id>
<content type='text'>
[ Upstream commit d9a9280a0d0ae51dc1d4142138b99242b7ec8ac6 ]

Building with W=2 prints a number of warnings for one function that
has a pointer type mismatch:

linux/seq_buf.h: In function 'seq_buf_init':
linux/seq_buf.h:35:12: warning: pointer targets in assignment from 'unsigned char *' to 'char *' differ in signedness [-Wpointer-sign]

Change the type in the function prototype according to the type in
the structure.

Link: https://lkml.kernel.org/r/20201026161108.3707783-1-arnd@kernel.org

Fixes: 9a7777935c34 ("tracing: Convert seq_buf fields to be like seq_file fields")
Reviewed-by: Cezary Rojewski &lt;cezary.rojewski@intel.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&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 d9a9280a0d0ae51dc1d4142138b99242b7ec8ac6 ]

Building with W=2 prints a number of warnings for one function that
has a pointer type mismatch:

linux/seq_buf.h: In function 'seq_buf_init':
linux/seq_buf.h:35:12: warning: pointer targets in assignment from 'unsigned char *' to 'char *' differ in signedness [-Wpointer-sign]

Change the type in the function prototype according to the type in
the structure.

Link: https://lkml.kernel.org/r/20201026161108.3707783-1-arnd@kernel.org

Fixes: 9a7777935c34 ("tracing: Convert seq_buf fields to be like seq_file fields")
Reviewed-by: Cezary Rojewski &lt;cezary.rojewski@intel.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>spi: Introduce device-managed SPI controller allocation</title>
<updated>2020-12-11T12:36:45+00:00</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2020-12-06T12:53:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a4add022c1552b0d51a0b89a4781919d6ebac4f9'/>
<id>a4add022c1552b0d51a0b89a4781919d6ebac4f9</id>
<content type='text'>
[ Upstream commit 5e844cc37a5cbaa460e68f9a989d321d63088a89 ]

SPI driver probing currently comprises two steps, whereas removal
comprises only one step:

    spi_alloc_master()
    spi_register_master()

    spi_unregister_master()

That's because spi_unregister_master() calls device_unregister()
instead of device_del(), thereby releasing the reference on the
spi_master which was obtained by spi_alloc_master().

An SPI driver's private data is contained in the same memory allocation
as the spi_master struct.  Thus, once spi_unregister_master() has been
called, the private data is inaccessible.  But some drivers need to
access it after spi_unregister_master() to perform further teardown
steps.

Introduce devm_spi_alloc_master(), which releases a reference on the
spi_master struct only after the driver has unbound, thereby keeping the
memory allocation accessible.  Change spi_unregister_master() to not
release a reference if the spi_master was allocated by the new devm
function.

The present commit is small enough to be backportable to stable.
It allows fixing drivers which use the private data in their -&gt;remove()
hook after it's been freed.  It also allows fixing drivers which neglect
to release a reference on the spi_master in the probe error path.

Long-term, most SPI drivers shall be moved over to the devm function
introduced herein.  The few that can't shall be changed in a treewide
commit to explicitly release the last reference on the master.
That commit shall amend spi_unregister_master() to no longer release
a reference, thereby completing the migration.

As a result, the behaviour will be less surprising and more consistent
with subsystems such as IIO, which also includes the private data in the
allocation of the generic iio_dev struct, but calls device_del() in
iio_device_unregister().

Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown &lt;broonie@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>
[ Upstream commit 5e844cc37a5cbaa460e68f9a989d321d63088a89 ]

SPI driver probing currently comprises two steps, whereas removal
comprises only one step:

    spi_alloc_master()
    spi_register_master()

    spi_unregister_master()

That's because spi_unregister_master() calls device_unregister()
instead of device_del(), thereby releasing the reference on the
spi_master which was obtained by spi_alloc_master().

An SPI driver's private data is contained in the same memory allocation
as the spi_master struct.  Thus, once spi_unregister_master() has been
called, the private data is inaccessible.  But some drivers need to
access it after spi_unregister_master() to perform further teardown
steps.

Introduce devm_spi_alloc_master(), which releases a reference on the
spi_master struct only after the driver has unbound, thereby keeping the
memory allocation accessible.  Change spi_unregister_master() to not
release a reference if the spi_master was allocated by the new devm
function.

The present commit is small enough to be backportable to stable.
It allows fixing drivers which use the private data in their -&gt;remove()
hook after it's been freed.  It also allows fixing drivers which neglect
to release a reference on the spi_master in the probe error path.

Long-term, most SPI drivers shall be moved over to the devm function
introduced herein.  The few that can't shall be changed in a treewide
commit to explicitly release the last reference on the master.
That commit shall amend spi_unregister_master() to no longer release
a reference, thereby completing the migration.

As a result, the behaviour will be less surprising and more consistent
with subsystems such as IIO, which also includes the private data in the
allocation of the generic iio_dev struct, but calls device_del() in
iio_device_unregister().

Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: Fix -&gt;session locking</title>
<updated>2020-12-11T12:36:45+00:00</updated>
<author>
<name>Jann Horn</name>
<email>jannh@google.com</email>
</author>
<published>2020-12-03T01:25:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7b4a4b9403c52343d00901babc3987588bc0b085'/>
<id>7b4a4b9403c52343d00901babc3987588bc0b085</id>
<content type='text'>
commit c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9 upstream.

Currently, locking of -&gt;session is very inconsistent; most places
protect it using the legacy tty mutex, but disassociate_ctty(),
__do_SAK(), tiocspgrp() and tiocgsid() don't.
Two of the writers hold the ctrl_lock (because they already need it for
-&gt;pgrp), but __proc_set_tty() doesn't do that yet.

On a PREEMPT=y system, an unprivileged user can theoretically abuse
this broken locking to read 4 bytes of freed memory via TIOCGSID if
tiocgsid() is preempted long enough at the right point. (Other things
might also go wrong, especially if root-only ioctls are involved; I'm
not sure about that.)

Change the locking on -&gt;session such that:

 - tty_lock() is held by all writers: By making disassociate_ctty()
   hold it. This should be fine because the same lock can already be
   taken through the call to tty_vhangup_session().
   The tricky part is that we need to shorten the area covered by
   siglock to be able to take tty_lock() without ugly retry logic; as
   far as I can tell, this should be fine, since nothing in the
   signal_struct is touched in the `if (tty)` branch.
 - ctrl_lock is held by all writers: By changing __proc_set_tty() to
   hold the lock a little longer.
 - All readers that aren't holding tty_lock() hold ctrl_lock: By
   adding locking to tiocgsid() and __do_SAK(), and expanding the area
   covered by ctrl_lock in tiocspgrp().

Cc: stable@kernel.org
Signed-off-by: Jann Horn &lt;jannh@google.com&gt;
Reviewed-by: Jiri Slaby &lt;jirislaby@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 c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9 upstream.

Currently, locking of -&gt;session is very inconsistent; most places
protect it using the legacy tty mutex, but disassociate_ctty(),
__do_SAK(), tiocspgrp() and tiocgsid() don't.
Two of the writers hold the ctrl_lock (because they already need it for
-&gt;pgrp), but __proc_set_tty() doesn't do that yet.

On a PREEMPT=y system, an unprivileged user can theoretically abuse
this broken locking to read 4 bytes of freed memory via TIOCGSID if
tiocgsid() is preempted long enough at the right point. (Other things
might also go wrong, especially if root-only ioctls are involved; I'm
not sure about that.)

Change the locking on -&gt;session such that:

 - tty_lock() is held by all writers: By making disassociate_ctty()
   hold it. This should be fine because the same lock can already be
   taken through the call to tty_vhangup_session().
   The tricky part is that we need to shorten the area covered by
   siglock to be able to take tty_lock() without ugly retry logic; as
   far as I can tell, this should be fine, since nothing in the
   signal_struct is touched in the `if (tty)` branch.
 - ctrl_lock is held by all writers: By changing __proc_set_tty() to
   hold the lock a little longer.
 - All readers that aren't holding tty_lock() hold ctrl_lock: By
   adding locking to tiocgsid() and __do_SAK(), and expanding the area
   covered by ctrl_lock in tiocspgrp().

Cc: stable@kernel.org
Signed-off-by: Jann Horn &lt;jannh@google.com&gt;
Reviewed-by: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>vlan: consolidate VLAN parsing code and limit max parsing depth</title>
<updated>2020-12-11T12:36:44+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@redhat.com</email>
</author>
<published>2020-07-07T11:03:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bb7b26278b384dad1423101dc69157b63968ed1c'/>
<id>bb7b26278b384dad1423101dc69157b63968ed1c</id>
<content type='text'>
[ Upstream commit 469aceddfa3ed16e17ee30533fae45e90f62efd8 ]

Toshiaki pointed out that we now have two very similar functions to extract
the L3 protocol number in the presence of VLAN tags. And Daniel pointed out
that the unbounded parsing loop makes it possible for maliciously crafted
packets to loop through potentially hundreds of tags.

Fix both of these issues by consolidating the two parsing functions and
limiting the VLAN tag parsing to a max depth of 8 tags. As part of this,
switch over __vlan_get_protocol() to use skb_header_pointer() instead of
pskb_may_pull(), to avoid the possible side effects of the latter and keep
the skb pointer 'const' through all the parsing functions.

v2:
- Use limit of 8 tags instead of 32 (matching XMIT_RECURSION_LIMIT)

Reported-by: Toshiaki Makita &lt;toshiaki.makita1@gmail.com&gt;
Reported-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Fixes: d7bf2ebebc2b ("sched: consistently handle layer3 header accesses in the presence of VLANs")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&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 469aceddfa3ed16e17ee30533fae45e90f62efd8 ]

Toshiaki pointed out that we now have two very similar functions to extract
the L3 protocol number in the presence of VLAN tags. And Daniel pointed out
that the unbounded parsing loop makes it possible for maliciously crafted
packets to loop through potentially hundreds of tags.

Fix both of these issues by consolidating the two parsing functions and
limiting the VLAN tag parsing to a max depth of 8 tags. As part of this,
switch over __vlan_get_protocol() to use skb_header_pointer() instead of
pskb_may_pull(), to avoid the possible side effects of the latter and keep
the skb pointer 'const' through all the parsing functions.

v2:
- Use limit of 8 tags instead of 32 (matching XMIT_RECURSION_LIMIT)

Reported-by: Toshiaki Makita &lt;toshiaki.makita1@gmail.com&gt;
Reported-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Fixes: d7bf2ebebc2b ("sched: consistently handle layer3 header accesses in the presence of VLANs")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bonding: wait for sysfs kobject destruction before freeing struct slave</title>
<updated>2020-12-11T12:36:43+00:00</updated>
<author>
<name>Jamie Iles</name>
<email>jamie@nuviainc.com</email>
</author>
<published>2020-11-20T14:28:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ecfcf31929f33924452ae95c7b10a2d15c07e42d'/>
<id>ecfcf31929f33924452ae95c7b10a2d15c07e42d</id>
<content type='text'>
[ Upstream commit b9ad3e9f5a7a760ab068e33e1f18d240ba32ce92 ]

syzkaller found that with CONFIG_DEBUG_KOBJECT_RELEASE=y, releasing a
struct slave device could result in the following splat:

  kobject: 'bonding_slave' (00000000cecdd4fe): kobject_release, parent 0000000074ceb2b2 (delayed 1000)
  bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
  ------------[ cut here ]------------
  ODEBUG: free active (active state 0) object type: timer_list hint: workqueue_select_cpu_near kernel/workqueue.c:1549 [inline]
  ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x98 kernel/workqueue.c:1600
  WARNING: CPU: 1 PID: 842 at lib/debugobjects.c:485 debug_print_object+0x180/0x240 lib/debugobjects.c:485
  Kernel panic - not syncing: panic_on_warn set ...
  CPU: 1 PID: 842 Comm: kworker/u4:4 Tainted: G S                5.9.0-rc8+ #96
  Hardware name: linux,dummy-virt (DT)
  Workqueue: netns cleanup_net
  Call trace:
   dump_backtrace+0x0/0x4d8 include/linux/bitmap.h:239
   show_stack+0x34/0x48 arch/arm64/kernel/traps.c:142
   __dump_stack lib/dump_stack.c:77 [inline]
   dump_stack+0x174/0x1f8 lib/dump_stack.c:118
   panic+0x360/0x7a0 kernel/panic.c:231
   __warn+0x244/0x2ec kernel/panic.c:600
   report_bug+0x240/0x398 lib/bug.c:198
   bug_handler+0x50/0xc0 arch/arm64/kernel/traps.c:974
   call_break_hook+0x160/0x1d8 arch/arm64/kernel/debug-monitors.c:322
   brk_handler+0x30/0xc0 arch/arm64/kernel/debug-monitors.c:329
   do_debug_exception+0x184/0x340 arch/arm64/mm/fault.c:864
   el1_dbg+0x48/0xb0 arch/arm64/kernel/entry-common.c:65
   el1_sync_handler+0x170/0x1c8 arch/arm64/kernel/entry-common.c:93
   el1_sync+0x80/0x100 arch/arm64/kernel/entry.S:594
   debug_print_object+0x180/0x240 lib/debugobjects.c:485
   __debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
   debug_check_no_obj_freed+0x200/0x430 lib/debugobjects.c:998
   slab_free_hook mm/slub.c:1536 [inline]
   slab_free_freelist_hook+0x190/0x210 mm/slub.c:1577
   slab_free mm/slub.c:3138 [inline]
   kfree+0x13c/0x460 mm/slub.c:4119
   bond_free_slave+0x8c/0xf8 drivers/net/bonding/bond_main.c:1492
   __bond_release_one+0xe0c/0xec8 drivers/net/bonding/bond_main.c:2190
   bond_slave_netdev_event drivers/net/bonding/bond_main.c:3309 [inline]
   bond_netdev_event+0x8f0/0xa70 drivers/net/bonding/bond_main.c:3420
   notifier_call_chain+0xf0/0x200 kernel/notifier.c:83
   __raw_notifier_call_chain kernel/notifier.c:361 [inline]
   raw_notifier_call_chain+0x44/0x58 kernel/notifier.c:368
   call_netdevice_notifiers_info+0xbc/0x150 net/core/dev.c:2033
   call_netdevice_notifiers_extack net/core/dev.c:2045 [inline]
   call_netdevice_notifiers net/core/dev.c:2059 [inline]
   rollback_registered_many+0x6a4/0xec0 net/core/dev.c:9347
   unregister_netdevice_many.part.0+0x2c/0x1c0 net/core/dev.c:10509
   unregister_netdevice_many net/core/dev.c:10508 [inline]
   default_device_exit_batch+0x294/0x338 net/core/dev.c:10992
   ops_exit_list.isra.0+0xec/0x150 net/core/net_namespace.c:189
   cleanup_net+0x44c/0x888 net/core/net_namespace.c:603
   process_one_work+0x96c/0x18c0 kernel/workqueue.c:2269
   worker_thread+0x3f0/0xc30 kernel/workqueue.c:2415
   kthread+0x390/0x498 kernel/kthread.c:292
   ret_from_fork+0x10/0x18 arch/arm64/kernel/entry.S:925

This is a potential use-after-free if the sysfs nodes are being accessed
whilst removing the struct slave, so wait for the object destruction to
complete before freeing the struct slave itself.

Fixes: 07699f9a7c8d ("bonding: add sysfs /slave dir for bond slave devices.")
Fixes: a068aab42258 ("bonding: Fix reference count leak in bond_sysfs_slave_add.")
Cc: Qiushi Wu &lt;wu000273@umn.edu&gt;
Cc: Jay Vosburgh &lt;j.vosburgh@gmail.com&gt;
Cc: Veaceslav Falico &lt;vfalico@gmail.com&gt;
Cc: Andy Gospodarek &lt;andy@greyhouse.net&gt;
Signed-off-by: Jamie Iles &lt;jamie@nuviainc.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20201120142827.879226-1-jamie@nuviainc.com
Signed-off-by: Jakub Kicinski &lt;kuba@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>
[ Upstream commit b9ad3e9f5a7a760ab068e33e1f18d240ba32ce92 ]

syzkaller found that with CONFIG_DEBUG_KOBJECT_RELEASE=y, releasing a
struct slave device could result in the following splat:

  kobject: 'bonding_slave' (00000000cecdd4fe): kobject_release, parent 0000000074ceb2b2 (delayed 1000)
  bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
  ------------[ cut here ]------------
  ODEBUG: free active (active state 0) object type: timer_list hint: workqueue_select_cpu_near kernel/workqueue.c:1549 [inline]
  ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x98 kernel/workqueue.c:1600
  WARNING: CPU: 1 PID: 842 at lib/debugobjects.c:485 debug_print_object+0x180/0x240 lib/debugobjects.c:485
  Kernel panic - not syncing: panic_on_warn set ...
  CPU: 1 PID: 842 Comm: kworker/u4:4 Tainted: G S                5.9.0-rc8+ #96
  Hardware name: linux,dummy-virt (DT)
  Workqueue: netns cleanup_net
  Call trace:
   dump_backtrace+0x0/0x4d8 include/linux/bitmap.h:239
   show_stack+0x34/0x48 arch/arm64/kernel/traps.c:142
   __dump_stack lib/dump_stack.c:77 [inline]
   dump_stack+0x174/0x1f8 lib/dump_stack.c:118
   panic+0x360/0x7a0 kernel/panic.c:231
   __warn+0x244/0x2ec kernel/panic.c:600
   report_bug+0x240/0x398 lib/bug.c:198
   bug_handler+0x50/0xc0 arch/arm64/kernel/traps.c:974
   call_break_hook+0x160/0x1d8 arch/arm64/kernel/debug-monitors.c:322
   brk_handler+0x30/0xc0 arch/arm64/kernel/debug-monitors.c:329
   do_debug_exception+0x184/0x340 arch/arm64/mm/fault.c:864
   el1_dbg+0x48/0xb0 arch/arm64/kernel/entry-common.c:65
   el1_sync_handler+0x170/0x1c8 arch/arm64/kernel/entry-common.c:93
   el1_sync+0x80/0x100 arch/arm64/kernel/entry.S:594
   debug_print_object+0x180/0x240 lib/debugobjects.c:485
   __debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
   debug_check_no_obj_freed+0x200/0x430 lib/debugobjects.c:998
   slab_free_hook mm/slub.c:1536 [inline]
   slab_free_freelist_hook+0x190/0x210 mm/slub.c:1577
   slab_free mm/slub.c:3138 [inline]
   kfree+0x13c/0x460 mm/slub.c:4119
   bond_free_slave+0x8c/0xf8 drivers/net/bonding/bond_main.c:1492
   __bond_release_one+0xe0c/0xec8 drivers/net/bonding/bond_main.c:2190
   bond_slave_netdev_event drivers/net/bonding/bond_main.c:3309 [inline]
   bond_netdev_event+0x8f0/0xa70 drivers/net/bonding/bond_main.c:3420
   notifier_call_chain+0xf0/0x200 kernel/notifier.c:83
   __raw_notifier_call_chain kernel/notifier.c:361 [inline]
   raw_notifier_call_chain+0x44/0x58 kernel/notifier.c:368
   call_netdevice_notifiers_info+0xbc/0x150 net/core/dev.c:2033
   call_netdevice_notifiers_extack net/core/dev.c:2045 [inline]
   call_netdevice_notifiers net/core/dev.c:2059 [inline]
   rollback_registered_many+0x6a4/0xec0 net/core/dev.c:9347
   unregister_netdevice_many.part.0+0x2c/0x1c0 net/core/dev.c:10509
   unregister_netdevice_many net/core/dev.c:10508 [inline]
   default_device_exit_batch+0x294/0x338 net/core/dev.c:10992
   ops_exit_list.isra.0+0xec/0x150 net/core/net_namespace.c:189
   cleanup_net+0x44c/0x888 net/core/net_namespace.c:603
   process_one_work+0x96c/0x18c0 kernel/workqueue.c:2269
   worker_thread+0x3f0/0xc30 kernel/workqueue.c:2415
   kthread+0x390/0x498 kernel/kthread.c:292
   ret_from_fork+0x10/0x18 arch/arm64/kernel/entry.S:925

This is a potential use-after-free if the sysfs nodes are being accessed
whilst removing the struct slave, so wait for the object destruction to
complete before freeing the struct slave itself.

Fixes: 07699f9a7c8d ("bonding: add sysfs /slave dir for bond slave devices.")
Fixes: a068aab42258 ("bonding: Fix reference count leak in bond_sysfs_slave_add.")
Cc: Qiushi Wu &lt;wu000273@umn.edu&gt;
Cc: Jay Vosburgh &lt;j.vosburgh@gmail.com&gt;
Cc: Veaceslav Falico &lt;vfalico@gmail.com&gt;
Cc: Andy Gospodarek &lt;andy@greyhouse.net&gt;
Signed-off-by: Jamie Iles &lt;jamie@nuviainc.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20201120142827.879226-1-jamie@nuviainc.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: core: add endpoint-blacklist quirk</title>
<updated>2020-12-02T07:29:29+00:00</updated>
<author>
<name>Johan Hovold</name>
<email>johan@kernel.org</email>
</author>
<published>2020-02-03T15:38:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d3fa1c6a3506d44e7f74f25fcb9beb1df66521f5'/>
<id>d3fa1c6a3506d44e7f74f25fcb9beb1df66521f5</id>
<content type='text'>
commit 73f8bda9b5dc1c69df2bc55c0cbb24461a6391a9 upstream

Add a new device quirk that can be used to blacklist endpoints.

Since commit 3e4f8e21c4f2 ("USB: core: fix check for duplicate
endpoints") USB core ignores any duplicate endpoints found during
descriptor parsing.

In order to handle devices where the first interfaces with duplicate
endpoints are the ones that should have their endpoints ignored, we need
to add a blacklist.

Tested-by: edes &lt;edes@gmx.net&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Link: https://lore.kernel.org/r/20200203153830.26394-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&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 73f8bda9b5dc1c69df2bc55c0cbb24461a6391a9 upstream

Add a new device quirk that can be used to blacklist endpoints.

Since commit 3e4f8e21c4f2 ("USB: core: fix check for duplicate
endpoints") USB core ignores any duplicate endpoints found during
descriptor parsing.

In order to handle devices where the first interfaces with duplicate
endpoints are the ones that should have their endpoints ignored, we need
to add a blacklist.

Tested-by: edes &lt;edes@gmx.net&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Link: https://lore.kernel.org/r/20200203153830.26394-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: libiscsi: Fix NOP race condition</title>
<updated>2020-12-02T07:29:28+00:00</updated>
<author>
<name>Lee Duncan</name>
<email>lduncan@suse.com</email>
</author>
<published>2020-11-06T19:33:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dd069602398522a76a339296bec086a72ef594d1'/>
<id>dd069602398522a76a339296bec086a72ef594d1</id>
<content type='text'>
[ Upstream commit fe0a8a95e7134d0b44cd407bc0085b9ba8d8fe31 ]

iSCSI NOPs are sometimes "lost", mistakenly sent to the user-land iscsid
daemon instead of handled in the kernel, as they should be, resulting in a
message from the daemon like:

  iscsid: Got nop in, but kernel supports nop handling.

This can occur because of the new forward- and back-locks, and the fact
that an iSCSI NOP response can occur before processing of the NOP send is
complete. This can result in "conn-&gt;ping_task" being NULL in
iscsi_nop_out_rsp(), when the pointer is actually in the process of being
set.

To work around this, we add a new state to the "ping_task" pointer. In
addition to NULL (not assigned) and a pointer (assigned), we add the state
"being set", which is signaled with an INVALID pointer (using "-1").

Link: https://lore.kernel.org/r/20201106193317.16993-1-leeman.duncan@gmail.com
Reviewed-by: Mike Christie &lt;michael.christie@oracle.com&gt;
Signed-off-by: Lee Duncan &lt;lduncan@suse.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&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 fe0a8a95e7134d0b44cd407bc0085b9ba8d8fe31 ]

iSCSI NOPs are sometimes "lost", mistakenly sent to the user-land iscsid
daemon instead of handled in the kernel, as they should be, resulting in a
message from the daemon like:

  iscsid: Got nop in, but kernel supports nop handling.

This can occur because of the new forward- and back-locks, and the fact
that an iSCSI NOP response can occur before processing of the NOP send is
complete. This can result in "conn-&gt;ping_task" being NULL in
iscsi_nop_out_rsp(), when the pointer is actually in the process of being
set.

To work around this, we add a new state to the "ping_task" pointer. In
addition to NULL (not assigned) and a pointer (assigned), we add the state
"being set", which is signaled with an INVALID pointer (using "-1").

Link: https://lore.kernel.org/r/20201106193317.16993-1-leeman.duncan@gmail.com
Reviewed-by: Mike Christie &lt;michael.christie@oracle.com&gt;
Signed-off-by: Lee Duncan &lt;lduncan@suse.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
