<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/net/l2tp, branch v5.14</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>l2tp: Fix spelling mistakes</title>
<updated>2021-06-07T21:08:30+00:00</updated>
<author>
<name>Zheng Yongjun</name>
<email>zhengyongjun3@huawei.com</email>
</author>
<published>2021-06-07T15:01:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7f553ff214105f49e973187488ff93ff9c56b0c8'/>
<id>7f553ff214105f49e973187488ff93ff9c56b0c8</id>
<content type='text'>
Fix some spelling mistakes in comments:
negociated  ==&gt; negotiated
dont  ==&gt; don't

Signed-off-by: Zheng Yongjun &lt;zhengyongjun3@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix some spelling mistakes in comments:
negociated  ==&gt; negotiated
dont  ==&gt; don't

Signed-off-by: Zheng Yongjun &lt;zhengyongjun3@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Remove the member netns_ok</title>
<updated>2021-05-17T22:29:35+00:00</updated>
<author>
<name>Yejune Deng</name>
<email>yejune.deng@gmail.com</email>
</author>
<published>2021-05-17T12:22:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5796254e467bf1cff002df65fbb53ecef6a0e060'/>
<id>5796254e467bf1cff002df65fbb53ecef6a0e060</id>
<content type='text'>
Every protocol has the 'netns_ok' member and it is euqal to 1. The
'if (!prot-&gt;netns_ok)' always false in inet_add_protocol().

Signed-off-by: Yejune Deng &lt;yejunedeng@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Every protocol has the 'netns_ok' member and it is euqal to 1. The
'if (!prot-&gt;netns_ok)' always false in inet_add_protocol().

Signed-off-by: Yejune Deng &lt;yejunedeng@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: fix a concurrency bug in l2tp_tunnel_register()</title>
<updated>2021-04-27T21:23:13+00:00</updated>
<author>
<name>Gong, Sishuai</name>
<email>sishuai@purdue.edu</email>
</author>
<published>2021-04-27T15:04:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=69e16d01d1de4f1249869de342915f608feb55d5'/>
<id>69e16d01d1de4f1249869de342915f608feb55d5</id>
<content type='text'>
l2tp_tunnel_register() registers a tunnel without fully
initializing its attribute. This can allow another kernel thread
running l2tp_xmit_core() to access the uninitialized data and
then cause a kernel NULL pointer dereference error, as shown below.

Thread 1    Thread 2
//l2tp_tunnel_register()
list_add_rcu(&amp;tunnel-&gt;list, &amp;pn-&gt;l2tp_tunnel_list);
           //pppol2tp_connect()
           tunnel = l2tp_tunnel_get(sock_net(sk), info.tunnel_id);
           // Fetch the new tunnel
           ...
           //l2tp_xmit_core()
           struct sock *sk = tunnel-&gt;sock;
           ...
           bh_lock_sock(sk);
           //Null pointer error happens
tunnel-&gt;sock = sk;

Fix this bug by initializing tunnel-&gt;sock before adding the
tunnel into l2tp_tunnel_list.

Reviewed-by: Cong Wang &lt;cong.wang@bytedance.com&gt;
Signed-off-by: Sishuai Gong &lt;sishuai@purdue.edu&gt;
Reported-by: Sishuai Gong &lt;sishuai@purdue.edu&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
l2tp_tunnel_register() registers a tunnel without fully
initializing its attribute. This can allow another kernel thread
running l2tp_xmit_core() to access the uninitialized data and
then cause a kernel NULL pointer dereference error, as shown below.

Thread 1    Thread 2
//l2tp_tunnel_register()
list_add_rcu(&amp;tunnel-&gt;list, &amp;pn-&gt;l2tp_tunnel_list);
           //pppol2tp_connect()
           tunnel = l2tp_tunnel_get(sock_net(sk), info.tunnel_id);
           // Fetch the new tunnel
           ...
           //l2tp_xmit_core()
           struct sock *sk = tunnel-&gt;sock;
           ...
           bh_lock_sock(sk);
           //Null pointer error happens
tunnel-&gt;sock = sk;

Fix this bug by initializing tunnel-&gt;sock before adding the
tunnel into l2tp_tunnel_list.

Reviewed-by: Cong Wang &lt;cong.wang@bytedance.com&gt;
Signed-off-by: Sishuai Gong &lt;sishuai@purdue.edu&gt;
Reported-by: Sishuai Gong &lt;sishuai@purdue.edu&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: l2tp: Fix a typo</title>
<updated>2021-03-22T20:17:49+00:00</updated>
<author>
<name>Bhaskar Chowdhury</name>
<email>unixbhaskar@gmail.com</email>
</author>
<published>2021-03-22T12:21:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=aa785f93fcb4e8c66f5d3de88cd7626774f13c1d'/>
<id>aa785f93fcb4e8c66f5d3de88cd7626774f13c1d</id>
<content type='text'>
s/verifed/verified/

Signed-off-by: Bhaskar Chowdhury &lt;unixbhaskar@gmail.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
s/verifed/verified/

Signed-off-by: Bhaskar Chowdhury &lt;unixbhaskar@gmail.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: l2tp: reduce log level of messages in receive path, add counter instead</title>
<updated>2021-03-04T00:55:02+00:00</updated>
<author>
<name>Matthias Schiffer</name>
<email>mschiffer@universe-factory.net</email>
</author>
<published>2021-03-03T15:50:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3e59e8856758eb5a2dfe1f831ef53b168fd58105'/>
<id>3e59e8856758eb5a2dfe1f831ef53b168fd58105</id>
<content type='text'>
Commit 5ee759cda51b ("l2tp: use standard API for warning log messages")
changed a number of warnings about invalid packets in the receive path
so that they are always shown, instead of only when a special L2TP debug
flag is set. Even with rate limiting these warnings can easily cause
significant log spam - potentially triggered by a malicious party
sending invalid packets on purpose.

In addition these warnings were noticed by projects like Tunneldigger [1],
which uses L2TP for its data path, but implements its own control
protocol (which is sufficiently different from L2TP data packets that it
would always be passed up to userspace even with future extensions of
L2TP).

Some of the warnings were already redundant, as l2tp_stats has a counter
for these packets. This commit adds one additional counter for invalid
packets that are passed up to userspace. Packets with unknown session are
not counted as invalid, as there is nothing wrong with the format of
these packets.

With the additional counter, all of these messages are either redundant
or benign, so we reduce them to pr_debug_ratelimited().

[1] https://github.com/wlanslovenija/tunneldigger/issues/160

Fixes: 5ee759cda51b ("l2tp: use standard API for warning log messages")
Signed-off-by: Matthias Schiffer &lt;mschiffer@universe-factory.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 5ee759cda51b ("l2tp: use standard API for warning log messages")
changed a number of warnings about invalid packets in the receive path
so that they are always shown, instead of only when a special L2TP debug
flag is set. Even with rate limiting these warnings can easily cause
significant log spam - potentially triggered by a malicious party
sending invalid packets on purpose.

In addition these warnings were noticed by projects like Tunneldigger [1],
which uses L2TP for its data path, but implements its own control
protocol (which is sufficiently different from L2TP data packets that it
would always be passed up to userspace even with future extensions of
L2TP).

Some of the warnings were already redundant, as l2tp_stats has a counter
for these packets. This commit adds one additional counter for invalid
packets that are passed up to userspace. Packets with unknown session are
not counted as invalid, as there is nothing wrong with the format of
these packets.

With the additional counter, all of these messages are either redundant
or benign, so we reduce them to pr_debug_ratelimited().

[1] https://github.com/wlanslovenija/tunneldigger/issues/160

Fixes: 5ee759cda51b ("l2tp: use standard API for warning log messages")
Signed-off-by: Matthias Schiffer &lt;mschiffer@universe-factory.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lsm,selinux: pass flowi_common instead of flowi to the LSM hooks</title>
<updated>2020-11-23T23:36:21+00:00</updated>
<author>
<name>Paul Moore</name>
<email>paul@paul-moore.com</email>
</author>
<published>2020-09-28T02:38:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3df98d79215ace13d1e91ddfc5a67a0f5acbd83f'/>
<id>3df98d79215ace13d1e91ddfc5a67a0f5acbd83f</id>
<content type='text'>
As pointed out by Herbert in a recent related patch, the LSM hooks do
not have the necessary address family information to use the flowi
struct safely.  As none of the LSMs currently use any of the protocol
specific flowi information, replace the flowi pointers with pointers
to the address family independent flowi_common struct.

Reported-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Acked-by: James Morris &lt;jamorris@linux.microsoft.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As pointed out by Herbert in a recent related patch, the LSM hooks do
not have the necessary address family information to use the flowi
struct safely.  As none of the LSMs currently use any of the protocol
specific flowi information, replace the flowi pointers with pointers
to the address family independent flowi_common struct.

Reported-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Acked-by: James Morris &lt;jamorris@linux.microsoft.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>genetlink: move to smaller ops wherever possible</title>
<updated>2020-10-03T02:11:11+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2020-10-02T21:49:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=66a9b9287d2447a91cef2fafc648dee32186f708'/>
<id>66a9b9287d2447a91cef2fafc648dee32186f708</id>
<content type='text'>
Bulk of the genetlink users can use smaller ops, move them.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Bulk of the genetlink users can use smaller ops, move them.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>l2tp: report rx cookie discards in netlink get</title>
<updated>2020-09-29T20:26:36+00:00</updated>
<author>
<name>Tom Parkin</name>
<email>tparkin@katalix.com</email>
</author>
<published>2020-09-29T12:35:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3f47cb4c1cf3bceb2438ea962bfffc6665ee4a9f'/>
<id>3f47cb4c1cf3bceb2438ea962bfffc6665ee4a9f</id>
<content type='text'>
When an L2TPv3 session receives a data frame with an incorrect cookie
l2tp_core logs a warning message and bumps a stats counter to reflect
the fact that the packet has been dropped.

However, the stats counter in question is missing from the l2tp_netlink
get message for tunnel and session instances.

Include the statistic in the netlink get response.

Signed-off-by: Tom Parkin &lt;tparkin@katalix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When an L2TPv3 session receives a data frame with an incorrect cookie
l2tp_core logs a warning message and bumps a stats counter to reflect
the fact that the packet has been dropped.

However, the stats counter in question is missing from the l2tp_netlink
get message for tunnel and session instances.

Include the statistic in the netlink get response.

Signed-off-by: Tom Parkin &lt;tparkin@katalix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>l2tp: fix up inconsistent rx/tx statistics</title>
<updated>2020-09-18T21:36:54+00:00</updated>
<author>
<name>Tom Parkin</name>
<email>tparkin@katalix.com</email>
</author>
<published>2020-09-18T10:23:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f52e4b27d1ac837caa84973262f7057578f6e316'/>
<id>f52e4b27d1ac837caa84973262f7057578f6e316</id>
<content type='text'>
Historically L2TP core statistics count the L2TP header in the
per-session and per-tunnel byte counts tracked for transmission and
receipt.

Now that l2tp_xmit_skb updates tx stats, it is necessary for
l2tp_xmit_core to pass out the length of the transmitted packet so that
the statistics can be updated correctly.

Signed-off-by: Tom Parkin &lt;tparkin@katalix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Historically L2TP core statistics count the L2TP header in the
per-session and per-tunnel byte counts tracked for transmission and
receipt.

Now that l2tp_xmit_skb updates tx stats, it is necessary for
l2tp_xmit_core to pass out the length of the transmitted packet so that
the statistics can be updated correctly.

Signed-off-by: Tom Parkin &lt;tparkin@katalix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>l2tp: avoid duplicated code in l2tp_tunnel_closeall</title>
<updated>2020-09-03T19:19:03+00:00</updated>
<author>
<name>Tom Parkin</name>
<email>tparkin@katalix.com</email>
</author>
<published>2020-09-03T08:54:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9d319a8e9309d6c2862e2f6721acb5b421af949e'/>
<id>9d319a8e9309d6c2862e2f6721acb5b421af949e</id>
<content type='text'>
l2tp_tunnel_closeall is called as a part of tunnel shutdown in order to
close all the sessions held by the tunnel.  The code it uses to close a
session duplicates what l2tp_session_delete does.

Rather than duplicating the code, have l2tp_tunnel_closeall call
l2tp_session_delete instead.

This involves a very minor change to locking in l2tp_tunnel_closeall.
Previously, l2tp_tunnel_closeall checked the session "dead" flag while
holding tunnel-&gt;hlist_lock.  This allowed for the code to step to the
next session in the list without releasing the lock if the current
session happened to be in the process of closing already.

By calling l2tp_session_delete instead, l2tp_tunnel_closeall must now
drop and regain the hlist lock for each session in the tunnel list.
Given that the likelihood of a session being in the process of closing
when the tunnel is closed, it seems worth this very minor potential
loss of efficiency to avoid duplication of the session delete code.

Signed-off-by: Tom Parkin &lt;tparkin@katalix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
l2tp_tunnel_closeall is called as a part of tunnel shutdown in order to
close all the sessions held by the tunnel.  The code it uses to close a
session duplicates what l2tp_session_delete does.

Rather than duplicating the code, have l2tp_tunnel_closeall call
l2tp_session_delete instead.

This involves a very minor change to locking in l2tp_tunnel_closeall.
Previously, l2tp_tunnel_closeall checked the session "dead" flag while
holding tunnel-&gt;hlist_lock.  This allowed for the code to step to the
next session in the list without releasing the lock if the current
session happened to be in the process of closing already.

By calling l2tp_session_delete instead, l2tp_tunnel_closeall must now
drop and regain the hlist lock for each session in the tunnel list.
Given that the likelihood of a session being in the process of closing
when the tunnel is closed, it seems worth this very minor potential
loss of efficiency to avoid duplication of the session delete code.

Signed-off-by: Tom Parkin &lt;tparkin@katalix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
