<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/net/ipv4/udp_offload.c, branch v4.6-rc5</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>net: Reset encap_level to avoid resetting features on inner IP headers</title>
<updated>2016-03-23T18:19:08+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-03-22T23:18:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5197f3499c470ccc4b247db66ff883e597e3adda'/>
<id>5197f3499c470ccc4b247db66ff883e597e3adda</id>
<content type='text'>
This patch corrects an oversight in which we were allowing the encap_level
value to pass from the outer headers to the inner headers.  As a result we
were incorrectly identifying UDP or GRE tunnels as also making use of ipip
or sit when the second header actually represented a tunnel encapsulated in
either a UDP or GRE tunnel which already had the features masked.

Fixes: 76443456227097179c1482 ("net: Move GSO csum into SKB_GSO_CB")
Reported-by: Tom Herbert &lt;tom@herbertland.com&gt;
Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.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>
This patch corrects an oversight in which we were allowing the encap_level
value to pass from the outer headers to the inner headers.  As a result we
were incorrectly identifying UDP or GRE tunnels as also making use of ipip
or sit when the second header actually represented a tunnel encapsulated in
either a UDP or GRE tunnel which already had the features masked.

Fixes: 76443456227097179c1482 ("net: Move GSO csum into SKB_GSO_CB")
Reported-by: Tom Herbert &lt;tom@herbertland.com&gt;
Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tunnels: Don't apply GRO to multiple layers of encapsulation.</title>
<updated>2016-03-20T20:33:40+00:00</updated>
<author>
<name>Jesse Gross</name>
<email>jesse@kernel.org</email>
</author>
<published>2016-03-19T16:32:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fac8e0f579695a3ecbc4d3cac369139d7f819971'/>
<id>fac8e0f579695a3ecbc4d3cac369139d7f819971</id>
<content type='text'>
When drivers express support for TSO of encapsulated packets, they
only mean that they can do it for one layer of encapsulation.
Supporting additional levels would mean updating, at a minimum,
more IP length fields and they are unaware of this.

No encapsulation device expresses support for handling offloaded
encapsulated packets, so we won't generate these types of frames
in the transmit path. However, GRO doesn't have a check for
multiple levels of encapsulation and will attempt to build them.

UDP tunnel GRO actually does prevent this situation but it only
handles multiple UDP tunnels stacked on top of each other. This
generalizes that solution to prevent any kind of tunnel stacking
that would cause problems.

Fixes: bf5a755f ("net-gre-gro: Add GRE support to the GRO stack")
Signed-off-by: Jesse Gross &lt;jesse@kernel.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>
When drivers express support for TSO of encapsulated packets, they
only mean that they can do it for one layer of encapsulation.
Supporting additional levels would mean updating, at a minimum,
more IP length fields and they are unaware of this.

No encapsulation device expresses support for handling offloaded
encapsulated packets, so we won't generate these types of frames
in the transmit path. However, GRO doesn't have a check for
multiple levels of encapsulation and will attempt to build them.

UDP tunnel GRO actually does prevent this situation but it only
handles multiple UDP tunnels stacked on top of each other. This
generalizes that solution to prevent any kind of tunnel stacking
that would cause problems.

Fixes: bf5a755f ("net-gre-gro: Add GRE support to the GRO stack")
Signed-off-by: Jesse Gross &lt;jesse@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>GSO/UDP: Use skb-&gt;len instead of udph-&gt;len to determine length of original skb</title>
<updated>2016-03-14T03:55:14+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-03-11T22:05:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=08334824951dd6d1295860da07b1236d18b0b8df'/>
<id>08334824951dd6d1295860da07b1236d18b0b8df</id>
<content type='text'>
It is possible for tunnels to end up generating IP or IPv6 datagrams that
are larger than 64K and expecting to be segmented.  As such we need to deal
with length values greater than 64K.  In order to accommodate this we need
to update the code to work with a 32b length value instead of a 16b one.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.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>
It is possible for tunnels to end up generating IP or IPv6 datagrams that
are larger than 64K and expecting to be segmented.  As such we need to deal
with length values greater than 64K.  In order to accommodate this we need
to update the code to work with a 32b length value instead of a 16b one.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>GSO: Provide software checksum of tunneled UDP fragmentation offload</title>
<updated>2016-02-26T19:23:35+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-02-25T00:46:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=224638766235ba82c53b4216e4dabc510701fbf2'/>
<id>224638766235ba82c53b4216e4dabc510701fbf2</id>
<content type='text'>
On reviewing the code I realized that GRE and UDP tunnels could cause a
kernel panic if we used GSO to segment a large UDP frame that was sent
through the tunnel with an outer checksum and hardware offloads were not
available.

In order to correct this we need to update the feature flags that are
passed to the skb_segment function so that in the event of UDP
fragmentation being requested for the inner header the segmentation
function will correctly generate the checksum for the payload if we cannot
segment the outer header.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.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>
On reviewing the code I realized that GRE and UDP tunnels could cause a
kernel panic if we used GSO to segment a large UDP frame that was sent
through the tunnel with an outer checksum and hardware offloads were not
available.

In order to correct this we need to update the feature flags that are
passed to the skb_segment function so that in the event of UDP
fragmentation being requested for the inner header the segmentation
function will correctly generate the checksum for the payload if we cannot
segment the outer header.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: Use uh-&gt;len instead of skb-&gt;len to compute checksum in segmentation</title>
<updated>2016-02-11T13:55:34+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-02-05T23:28:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=dbef491ebe7f3a4fb1b9111878b86a426fd540b7'/>
<id>dbef491ebe7f3a4fb1b9111878b86a426fd540b7</id>
<content type='text'>
The segmentation code was having to do a bunch of work to pull the
skb-&gt;len and strip the udp header offset before the value could be used to
adjust the checksum.  Instead of doing all this work we can just use the
value that goes into uh-&gt;len since that is the correct value with the
correct byte order that we need anyway.  By using this value we can save
ourselves a bunch of pain as there is no need to do multiple byte swaps.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.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>
The segmentation code was having to do a bunch of work to pull the
skb-&gt;len and strip the udp header offset before the value could be used to
adjust the checksum.  Instead of doing all this work we can just use the
value that goes into uh-&gt;len since that is the correct value with the
correct byte order that we need anyway.  By using this value we can save
ourselves a bunch of pain as there is no need to do multiple byte swaps.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: Clean up the use of flags in UDP segmentation offload</title>
<updated>2016-02-11T13:55:34+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-02-05T23:28:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fdaefd62fd658b266a8f389cdf7991630b4bc7b4'/>
<id>fdaefd62fd658b266a8f389cdf7991630b4bc7b4</id>
<content type='text'>
This patch goes though and cleans up the logic related to several of the
control flags used in UDP segmentation.  Specifically the use of dont_encap
isn't really needed as we can just check the skb for CHECKSUM_PARTIAL and
if it isn't set then we don't need to update the internal headers.  As such
we can just drop that value.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.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>
This patch goes though and cleans up the logic related to several of the
control flags used in UDP segmentation.  Specifically the use of dont_encap
isn't really needed as we can just check the skb for CHECKSUM_PARTIAL and
if it isn't set then we don't need to update the internal headers.  As such
we can just drop that value.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Update remote checksum segmentation to support use of GSO checksum</title>
<updated>2016-02-11T13:55:33+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-02-05T23:27:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7fbeffed77c130ecf64e8a2f7f9d6d63a9d60a19'/>
<id>7fbeffed77c130ecf64e8a2f7f9d6d63a9d60a19</id>
<content type='text'>
This patch addresses two main issues.

First in the case of remote checksum offload we were avoiding dealing with
scatter-gather issues.  As a result it would be possible to assemble a
series of frames that used frags instead of being linearized as they should
have if remote checksum offload was enabled.

Second I have updated the code so that we now let GSO take care of doing
the checksum on the data itself and drop the special case that was added
for remote checksum offload.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.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>
This patch addresses two main issues.

First in the case of remote checksum offload we were avoiding dealing with
scatter-gather issues.  As a result it would be possible to assemble a
series of frames that used frags instead of being linearized as they should
have if remote checksum offload was enabled.

Second I have updated the code so that we now let GSO take care of doing
the checksum on the data itself and drop the special case that was added
for remote checksum offload.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Drop unecessary enc_features variable from tunnel segmentation functions</title>
<updated>2016-02-11T13:55:33+00:00</updated>
<author>
<name>Alexander Duyck</name>
<email>aduyck@mirantis.com</email>
</author>
<published>2016-02-05T23:27:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bef3c6c9374da40ec63698cd504474366a9de2ff'/>
<id>bef3c6c9374da40ec63698cd504474366a9de2ff</id>
<content type='text'>
The enc_features variable isn't necessary since features isn't used
anywhere after we create enc_features so instead just use a destructive AND
on features itself and save ourselves the variable declaration.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.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>
The enc_features variable isn't necessary since features isn't used
anywhere after we create enc_features so instead just use a destructive AND
on features itself and save ourselves the variable declaration.

Signed-off-by: Alexander Duyck &lt;aduyck@mirantis.com&gt;
Acked-by: Tom Herbert &lt;tom@herbertland.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2016-01-12T04:55:43+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2016-01-12T04:55:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9d367eddf363553c7668ba92c3b9d187ec4f71f7'/>
<id>9d367eddf363553c7668ba92c3b9d187ec4f71f7</id>
<content type='text'>
Conflicts:
	drivers/net/bonding/bond_main.c
	drivers/net/ethernet/mellanox/mlxsw/spectrum.h
	drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c

The bond_main.c and mellanox switch conflicts were cases of
overlapping changes.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Conflicts:
	drivers/net/bonding/bond_main.c
	drivers/net/ethernet/mellanox/mlxsw/spectrum.h
	drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c

The bond_main.c and mellanox switch conflicts were cases of
overlapping changes.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: restrict offloads to one namespace</title>
<updated>2016-01-10T22:28:24+00:00</updated>
<author>
<name>Hannes Frederic Sowa</name>
<email>hannes@stressinduktion.org</email>
</author>
<published>2016-01-07T13:28:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=787d7ac308ff2279e4b2ea393ad4d990de486ef2'/>
<id>787d7ac308ff2279e4b2ea393ad4d990de486ef2</id>
<content type='text'>
udp tunnel offloads tend to aggregate datagrams based on inner
headers. gro engine gets notified by tunnel implementations about
possible offloads. The match is solely based on the port number.

Imagine a tunnel bound to port 53, the offloading will look into all
DNS packets and tries to aggregate them based on the inner data found
within. This could lead to data corruption and malformed DNS packets.

While this patch minimizes the problem and helps an administrator to find
the issue by querying ip tunnel/fou, a better way would be to match on
the specific destination ip address so if a user space socket is bound
to the same address it will conflict.

Cc: Tom Herbert &lt;tom@herbertland.com&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Hannes Frederic Sowa &lt;hannes@stressinduktion.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>
udp tunnel offloads tend to aggregate datagrams based on inner
headers. gro engine gets notified by tunnel implementations about
possible offloads. The match is solely based on the port number.

Imagine a tunnel bound to port 53, the offloading will look into all
DNS packets and tries to aggregate them based on the inner data found
within. This could lead to data corruption and malformed DNS packets.

While this patch minimizes the problem and helps an administrator to find
the issue by querying ip tunnel/fou, a better way would be to match on
the specific destination ip address so if a user space socket is bound
to the same address it will conflict.

Cc: Tom Herbert &lt;tom@herbertland.com&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Hannes Frederic Sowa &lt;hannes@stressinduktion.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
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