<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/core, branch v5.4.217</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>net: neigh: don't call kfree_skb() under spin_lock_irqsave()</title>
<updated>2022-09-05T08:27:48+00:00</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2022-08-22T02:53:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0052348329c94f6c608ff0d5372c48e3ab1f4ba8'/>
<id>0052348329c94f6c608ff0d5372c48e3ab1f4ba8</id>
<content type='text'>
commit d5485d9dd24e1d04e5509916515260186eb1455c upstream.

It is not allowed to call kfree_skb() from hardware interrupt
context or with interrupts being disabled. So add all skb to
a tmp list, then free them after spin_unlock_irqrestore() at
once.

Fixes: 66ba215cb513 ("neigh: fix possible DoS due to net iface start/stop loop")
Suggested-by: Denis V. Lunev &lt;den@openvz.org&gt;
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&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 d5485d9dd24e1d04e5509916515260186eb1455c upstream.

It is not allowed to call kfree_skb() from hardware interrupt
context or with interrupts being disabled. So add all skb to
a tmp list, then free them after spin_unlock_irqrestore() at
once.

Fixes: 66ba215cb513 ("neigh: fix possible DoS due to net iface start/stop loop")
Suggested-by: Denis V. Lunev &lt;den@openvz.org&gt;
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>neigh: fix possible DoS due to net iface start/stop loop</title>
<updated>2022-09-05T08:27:46+00:00</updated>
<author>
<name>Denis V. Lunev</name>
<email>den@openvz.org</email>
</author>
<published>2022-08-11T15:20:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=51be9dd391fd25872b95708a0250f2f7722d2d8e'/>
<id>51be9dd391fd25872b95708a0250f2f7722d2d8e</id>
<content type='text'>
[ Upstream commit 66ba215cb51323e4e55e38fd5f250e0fae0cbc94 ]

Normal processing of ARP request (usually this is Ethernet broadcast
packet) coming to the host is looking like the following:
* the packet comes to arp_process() call and is passed through routing
  procedure
* the request is put into the queue using pneigh_enqueue() if
  corresponding ARP record is not local (common case for container
  records on the host)
* the request is processed by timer (within 80 jiffies by default) and
  ARP reply is sent from the same arp_process() using
  NEIGH_CB(skb)-&gt;flags &amp; LOCALLY_ENQUEUED condition (flag is set inside
  pneigh_enqueue())

And here the problem comes. Linux kernel calls pneigh_queue_purge()
which destroys the whole queue of ARP requests on ANY network interface
start/stop event through __neigh_ifdown().

This is actually not a problem within the original world as network
interface start/stop was accessible to the host 'root' only, which
could do more destructive things. But the world is changed and there
are Linux containers available. Here container 'root' has an access
to this API and could be considered as untrusted user in the hosting
(container's) world.

Thus there is an attack vector to other containers on node when
container's root will endlessly start/stop interfaces. We have observed
similar situation on a real production node when docker container was
doing such activity and thus other containers on the node become not
accessible.

The patch proposed doing very simple thing. It drops only packets from
the same namespace in the pneigh_queue_purge() where network interface
state change is detected. This is enough to prevent the problem for the
whole node preserving original semantics of the code.

v2:
	- do del_timer_sync() if queue is empty after pneigh_queue_purge()
v3:
	- rebase to net tree

Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: David Ahern &lt;dsahern@kernel.org&gt;
Cc: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Cc: Roopa Prabhu &lt;roopa@nvidia.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Alexey Kuznetsov &lt;kuznet@ms2.inr.ac.ru&gt;
Cc: Alexander Mikhalitsyn &lt;alexander.mikhalitsyn@virtuozzo.com&gt;
Cc: Konstantin Khorenko &lt;khorenko@virtuozzo.com&gt;
Cc: kernel@openvz.org
Cc: devel@openvz.org
Investigated-by: Alexander Mikhalitsyn &lt;alexander.mikhalitsyn@virtuozzo.com&gt;
Signed-off-by: Denis V. Lunev &lt;den@openvz.org&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 66ba215cb51323e4e55e38fd5f250e0fae0cbc94 ]

Normal processing of ARP request (usually this is Ethernet broadcast
packet) coming to the host is looking like the following:
* the packet comes to arp_process() call and is passed through routing
  procedure
* the request is put into the queue using pneigh_enqueue() if
  corresponding ARP record is not local (common case for container
  records on the host)
* the request is processed by timer (within 80 jiffies by default) and
  ARP reply is sent from the same arp_process() using
  NEIGH_CB(skb)-&gt;flags &amp; LOCALLY_ENQUEUED condition (flag is set inside
  pneigh_enqueue())

And here the problem comes. Linux kernel calls pneigh_queue_purge()
which destroys the whole queue of ARP requests on ANY network interface
start/stop event through __neigh_ifdown().

This is actually not a problem within the original world as network
interface start/stop was accessible to the host 'root' only, which
could do more destructive things. But the world is changed and there
are Linux containers available. Here container 'root' has an access
to this API and could be considered as untrusted user in the hosting
(container's) world.

Thus there is an attack vector to other containers on node when
container's root will endlessly start/stop interfaces. We have observed
similar situation on a real production node when docker container was
doing such activity and thus other containers on the node become not
accessible.

The patch proposed doing very simple thing. It drops only packets from
the same namespace in the pneigh_queue_purge() where network interface
state change is detected. This is enough to prevent the problem for the
whole node preserving original semantics of the code.

v2:
	- do del_timer_sync() if queue is empty after pneigh_queue_purge()
v3:
	- rebase to net tree

Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: David Ahern &lt;dsahern@kernel.org&gt;
Cc: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Cc: Roopa Prabhu &lt;roopa@nvidia.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Alexey Kuznetsov &lt;kuznet@ms2.inr.ac.ru&gt;
Cc: Alexander Mikhalitsyn &lt;alexander.mikhalitsyn@virtuozzo.com&gt;
Cc: Konstantin Khorenko &lt;khorenko@virtuozzo.com&gt;
Cc: kernel@openvz.org
Cc: devel@openvz.org
Investigated-by: Alexander Mikhalitsyn &lt;alexander.mikhalitsyn@virtuozzo.com&gt;
Signed-off-by: Denis V. Lunev &lt;den@openvz.org&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>bpf: Don't redirect packets with invalid pkt_len</title>
<updated>2022-09-05T08:27:46+00:00</updated>
<author>
<name>Zhengchao Shao</name>
<email>shaozhengchao@huawei.com</email>
</author>
<published>2022-07-15T11:55:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b68e53d56697a59b5c53893b53f508bbdf272a0'/>
<id>8b68e53d56697a59b5c53893b53f508bbdf272a0</id>
<content type='text'>
commit fd1894224407c484f652ad456e1ce423e89bb3eb upstream.

Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any
skbs, that is, the flow-&gt;head is null.
The root cause, as the [2] says, is because that bpf_prog_test_run_skb()
run a bpf prog which redirects empty skbs.
So we should determine whether the length of the packet modified by bpf
prog or others like bpf_prog_test is valid before forwarding it directly.

LINK: [1] https://syzkaller.appspot.com/bug?id=0b84da80c2917757915afa89f7738a9d16ec96c5
LINK: [2] https://www.spinics.net/lists/netdev/msg777503.html

Reported-by: syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com
Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Reviewed-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Link: https://lore.kernel.org/r/20220715115559.139691-1-shaozhengchao@huawei.com
Signed-off-by: Alexei Starovoitov &lt;ast@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 fd1894224407c484f652ad456e1ce423e89bb3eb upstream.

Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any
skbs, that is, the flow-&gt;head is null.
The root cause, as the [2] says, is because that bpf_prog_test_run_skb()
run a bpf prog which redirects empty skbs.
So we should determine whether the length of the packet modified by bpf
prog or others like bpf_prog_test is valid before forwarding it directly.

LINK: [1] https://syzkaller.appspot.com/bug?id=0b84da80c2917757915afa89f7738a9d16ec96c5
LINK: [2] https://www.spinics.net/lists/netdev/msg777503.html

Reported-by: syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com
Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Reviewed-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Link: https://lore.kernel.org/r/20220715115559.139691-1-shaozhengchao@huawei.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Fix a data-race around netdev_budget_usecs.</title>
<updated>2022-09-05T08:27:42+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=923fa41adebdad77b25882a8b3882ef8cc237d4c'/>
<id>923fa41adebdad77b25882a8b3882ef8cc237d4c</id>
<content type='text'>
[ Upstream commit fa45d484c52c73f79db2c23b0cdfc6c6455093ad ]

While reading netdev_budget_usecs, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 7acf8a1e8a28 ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 fa45d484c52c73f79db2c23b0cdfc6c6455093ad ]

While reading netdev_budget_usecs, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 7acf8a1e8a28 ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>net: Fix a data-race around netdev_budget.</title>
<updated>2022-09-05T08:27:42+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=adeb24afd2fda697282913a58d8c2c95ab8693f0'/>
<id>adeb24afd2fda697282913a58d8c2c95ab8693f0</id>
<content type='text'>
[ Upstream commit 2e0c42374ee32e72948559d2ae2f7ba3dc6b977c ]

While reading netdev_budget, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 51b0bdedb8e7 ("[NET]: Separate two usages of netdev_max_backlog.")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 2e0c42374ee32e72948559d2ae2f7ba3dc6b977c ]

While reading netdev_budget, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 51b0bdedb8e7 ("[NET]: Separate two usages of netdev_max_backlog.")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>net: Fix a data-race around sysctl_net_busy_read.</title>
<updated>2022-09-05T08:27:42+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=575c57e9e00cb321b7efd162cf9554dec05ad5fe'/>
<id>575c57e9e00cb321b7efd162cf9554dec05ad5fe</id>
<content type='text'>
[ Upstream commit e59ef36f0795696ab229569c153936bfd068d21c ]

While reading sysctl_net_busy_read, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 2d48d67fa8cd ("net: poll/select low latency socket support")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 e59ef36f0795696ab229569c153936bfd068d21c ]

While reading sysctl_net_busy_read, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 2d48d67fa8cd ("net: poll/select low latency socket support")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>net: Fix a data-race around sysctl_tstamp_allow_data.</title>
<updated>2022-09-05T08:27:42+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5da0632c07d46aaaaf9533eb836b5c358e5abe37'/>
<id>5da0632c07d46aaaaf9533eb836b5c358e5abe37</id>
<content type='text'>
[ Upstream commit d2154b0afa73c0159b2856f875c6b4fe7cf6a95e ]

While reading sysctl_tstamp_allow_data, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: b245be1f4db1 ("net-timestamp: no-payload only sysctl")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 d2154b0afa73c0159b2856f875c6b4fe7cf6a95e ]

While reading sysctl_tstamp_allow_data, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: b245be1f4db1 ("net-timestamp: no-payload only sysctl")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>net: Fix data-races around netdev_tstamp_prequeue.</title>
<updated>2022-09-05T08:27:41+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a90afeab21aebc8085833d326872d83152f1a39c'/>
<id>a90afeab21aebc8085833d326872d83152f1a39c</id>
<content type='text'>
[ Upstream commit 61adf447e38664447526698872e21c04623afb8e ]

While reading netdev_tstamp_prequeue, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 3b098e2d7c69 ("net: Consistent skb timestamping")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 61adf447e38664447526698872e21c04623afb8e ]

While reading netdev_tstamp_prequeue, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 3b098e2d7c69 ("net: Consistent skb timestamping")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>net: Fix data-races around weight_p and dev_weight_[rt]x_bias.</title>
<updated>2022-09-05T08:27:41+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c1d0ef0e6f11e3ac78af5f32309f1c252c484139'/>
<id>c1d0ef0e6f11e3ac78af5f32309f1c252c484139</id>
<content type='text'>
[ Upstream commit bf955b5ab8f6f7b0632cdef8e36b14e4f6e77829 ]

While reading weight_p, it can be changed concurrently.  Thus, we need
to add READ_ONCE() to its reader.

Also, dev_[rt]x_weight can be read/written at the same time.  So, we
need to use READ_ONCE() and WRITE_ONCE() for its access.  Moreover, to
use the same weight_p while changing dev_[rt]x_weight, we add a mutex
in proc_do_dev_weight().

Fixes: 3d48b53fb2ae ("net: dev_weight: TX/RX orthogonality")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 bf955b5ab8f6f7b0632cdef8e36b14e4f6e77829 ]

While reading weight_p, it can be changed concurrently.  Thus, we need
to add READ_ONCE() to its reader.

Also, dev_[rt]x_weight can be read/written at the same time.  So, we
need to use READ_ONCE() and WRITE_ONCE() for its access.  Moreover, to
use the same weight_p while changing dev_[rt]x_weight, we add a mutex
in proc_do_dev_weight().

Fixes: 3d48b53fb2ae ("net: dev_weight: TX/RX orthogonality")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>devlink: Fix use-after-free after a failed reload</title>
<updated>2022-08-25T09:18:23+00:00</updated>
<author>
<name>Ido Schimmel</name>
<email>idosch@nvidia.com</email>
</author>
<published>2022-08-09T11:35:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1ad4ba9341f15412cf86dc6addbb73871a10212f'/>
<id>1ad4ba9341f15412cf86dc6addbb73871a10212f</id>
<content type='text'>
commit 6b4db2e528f650c7fb712961aac36455468d5902 upstream.

After a failed devlink reload, devlink parameters are still registered,
which means user space can set and get their values. In the case of the
mlxsw "acl_region_rehash_interval" parameter, these operations will
trigger a use-after-free [1].

Fix this by rejecting set and get operations while in the failed state.
Return the "-EOPNOTSUPP" error code which does not abort the parameters
dump, but instead causes it to skip over the problematic parameter.

Another possible fix is to perform these checks in the mlxsw parameter
callbacks, but other drivers might be affected by the same problem and I
am not aware of scenarios where these stricter checks will cause a
regression.

[1]
mlxsw_spectrum3 0000:00:10.0: Port 125: Failed to register netdev
mlxsw_spectrum3 0000:00:10.0: Failed to create ports

==================================================================
BUG: KASAN: use-after-free in mlxsw_sp_acl_tcam_vregion_rehash_intrvl_get+0xbd/0xd0 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c:904
Read of size 4 at addr ffff8880099dcfd8 by task kworker/u4:4/777

CPU: 1 PID: 777 Comm: kworker/u4:4 Not tainted 5.19.0-rc7-custom-126601-gfe26f28c586d #1
Hardware name: QEMU MSN4700, BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x92/0xbd lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:313 [inline]
 print_report.cold+0x5e/0x5cf mm/kasan/report.c:429
 kasan_report+0xb9/0xf0 mm/kasan/report.c:491
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 mlxsw_sp_acl_tcam_vregion_rehash_intrvl_get+0xbd/0xd0 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c:904
 mlxsw_sp_acl_region_rehash_intrvl_get+0x49/0x60 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c:1106
 mlxsw_sp_params_acl_region_rehash_intrvl_get+0x33/0x80 drivers/net/ethernet/mellanox/mlxsw/spectrum.c:3854
 devlink_param_get net/core/devlink.c:4981 [inline]
 devlink_nl_param_fill+0x238/0x12d0 net/core/devlink.c:5089
 devlink_param_notify+0xe5/0x230 net/core/devlink.c:5168
 devlink_ns_change_notify net/core/devlink.c:4417 [inline]
 devlink_ns_change_notify net/core/devlink.c:4396 [inline]
 devlink_reload+0x15f/0x700 net/core/devlink.c:4507
 devlink_pernet_pre_exit+0x112/0x1d0 net/core/devlink.c:12272
 ops_pre_exit_list net/core/net_namespace.c:152 [inline]
 cleanup_net+0x494/0xc00 net/core/net_namespace.c:582
 process_one_work+0x9fc/0x1710 kernel/workqueue.c:2289
 worker_thread+0x675/0x10b0 kernel/workqueue.c:2436
 kthread+0x30c/0x3d0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 &lt;/TASK&gt;

The buggy address belongs to the physical page:
page:ffffea0000267700 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x99dc
flags: 0x100000000000000(node=0|zone=1)
raw: 0100000000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880099dce80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880099dcf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
&gt;ffff8880099dcf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                    ^
 ffff8880099dd000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880099dd080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Fixes: 98bbf70c1c41 ("mlxsw: spectrum: add "acl_region_rehash_interval" devlink param")
Signed-off-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&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 6b4db2e528f650c7fb712961aac36455468d5902 upstream.

After a failed devlink reload, devlink parameters are still registered,
which means user space can set and get their values. In the case of the
mlxsw "acl_region_rehash_interval" parameter, these operations will
trigger a use-after-free [1].

Fix this by rejecting set and get operations while in the failed state.
Return the "-EOPNOTSUPP" error code which does not abort the parameters
dump, but instead causes it to skip over the problematic parameter.

Another possible fix is to perform these checks in the mlxsw parameter
callbacks, but other drivers might be affected by the same problem and I
am not aware of scenarios where these stricter checks will cause a
regression.

[1]
mlxsw_spectrum3 0000:00:10.0: Port 125: Failed to register netdev
mlxsw_spectrum3 0000:00:10.0: Failed to create ports

==================================================================
BUG: KASAN: use-after-free in mlxsw_sp_acl_tcam_vregion_rehash_intrvl_get+0xbd/0xd0 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c:904
Read of size 4 at addr ffff8880099dcfd8 by task kworker/u4:4/777

CPU: 1 PID: 777 Comm: kworker/u4:4 Not tainted 5.19.0-rc7-custom-126601-gfe26f28c586d #1
Hardware name: QEMU MSN4700, BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x92/0xbd lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:313 [inline]
 print_report.cold+0x5e/0x5cf mm/kasan/report.c:429
 kasan_report+0xb9/0xf0 mm/kasan/report.c:491
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 mlxsw_sp_acl_tcam_vregion_rehash_intrvl_get+0xbd/0xd0 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c:904
 mlxsw_sp_acl_region_rehash_intrvl_get+0x49/0x60 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c:1106
 mlxsw_sp_params_acl_region_rehash_intrvl_get+0x33/0x80 drivers/net/ethernet/mellanox/mlxsw/spectrum.c:3854
 devlink_param_get net/core/devlink.c:4981 [inline]
 devlink_nl_param_fill+0x238/0x12d0 net/core/devlink.c:5089
 devlink_param_notify+0xe5/0x230 net/core/devlink.c:5168
 devlink_ns_change_notify net/core/devlink.c:4417 [inline]
 devlink_ns_change_notify net/core/devlink.c:4396 [inline]
 devlink_reload+0x15f/0x700 net/core/devlink.c:4507
 devlink_pernet_pre_exit+0x112/0x1d0 net/core/devlink.c:12272
 ops_pre_exit_list net/core/net_namespace.c:152 [inline]
 cleanup_net+0x494/0xc00 net/core/net_namespace.c:582
 process_one_work+0x9fc/0x1710 kernel/workqueue.c:2289
 worker_thread+0x675/0x10b0 kernel/workqueue.c:2436
 kthread+0x30c/0x3d0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 &lt;/TASK&gt;

The buggy address belongs to the physical page:
page:ffffea0000267700 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x99dc
flags: 0x100000000000000(node=0|zone=1)
raw: 0100000000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880099dce80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880099dcf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
&gt;ffff8880099dcf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                    ^
 ffff8880099dd000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880099dd080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Fixes: 98bbf70c1c41 ("mlxsw: spectrum: add "acl_region_rehash_interval" devlink param")
Signed-off-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
