<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/netfilter, branch v4.9.78</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>netfilter: nfnetlink_queue: fix secctx memory leak</title>
<updated>2017-12-25T13:23:43+00:00</updated>
<author>
<name>Liping Zhang</name>
<email>zlpnobody@gmail.com</email>
</author>
<published>2017-03-28T14:59:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0708a476810d1a37422cb84ed3367be68045478f'/>
<id>0708a476810d1a37422cb84ed3367be68045478f</id>
<content type='text'>
[ Upstream commit 77c1c03c5b8ef28e55bb0aff29b1e006037ca645 ]

We must call security_release_secctx to free the memory returned by
security_secid_to_secctx, otherwise memory may be leaked forever.

Fixes: ef493bd930ae ("netfilter: nfnetlink_queue: add security context information")
Signed-off-by: Liping Zhang &lt;zlpnobody@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit 77c1c03c5b8ef28e55bb0aff29b1e006037ca645 ]

We must call security_release_secctx to free the memory returned by
security_secid_to_secctx, otherwise memory may be leaked forever.

Fixes: ef493bd930ae ("netfilter: nfnetlink_queue: add security context information")
Signed-off-by: Liping Zhang &lt;zlpnobody@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nfnl_cthelper: fix a race when walk the nf_ct_helper_hash table</title>
<updated>2017-12-25T13:23:41+00:00</updated>
<author>
<name>Liping Zhang</name>
<email>zlpnobody@gmail.com</email>
</author>
<published>2017-03-25T04:09:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=01060acf6aabea3ce3e362b0c29eeb6ab5fdfa63'/>
<id>01060acf6aabea3ce3e362b0c29eeb6ab5fdfa63</id>
<content type='text'>
[ Upstream commit 83d90219a5df8d950855ce73229a97b63605c317 ]

The nf_ct_helper_hash table is protected by nf_ct_helper_mutex, while
nfct_helper operation is protected by nfnl_lock(NFNL_SUBSYS_CTHELPER).
So it's possible that one CPU is walking the nf_ct_helper_hash for
cthelper add/get/del, another cpu is doing nf_conntrack_helpers_unregister
at the same time. This is dangrous, and may cause use after free error.

Note, delete operation will flush all cthelpers added via nfnetlink, so
using rcu to do protect is not easy.

Now introduce a dummy list to record all the cthelpers added via
nfnetlink, then we can walk the dummy list instead of walking the
nf_ct_helper_hash. Also, keep nfnl_cthelper_dump_table unchanged, it
may be invoked without nfnl_lock(NFNL_SUBSYS_CTHELPER) held.

Signed-off-by: Liping Zhang &lt;zlpnobody@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit 83d90219a5df8d950855ce73229a97b63605c317 ]

The nf_ct_helper_hash table is protected by nf_ct_helper_mutex, while
nfct_helper operation is protected by nfnl_lock(NFNL_SUBSYS_CTHELPER).
So it's possible that one CPU is walking the nf_ct_helper_hash for
cthelper add/get/del, another cpu is doing nf_conntrack_helpers_unregister
at the same time. This is dangrous, and may cause use after free error.

Note, delete operation will flush all cthelpers added via nfnetlink, so
using rcu to do protect is not easy.

Now introduce a dummy list to record all the cthelpers added via
nfnetlink, then we can walk the dummy list instead of walking the
nf_ct_helper_hash. Also, keep nfnl_cthelper_dump_table unchanged, it
may be invoked without nfnl_lock(NFNL_SUBSYS_CTHELPER) held.

Signed-off-by: Liping Zhang &lt;zlpnobody@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nfnl_cthelper: Fix memory leak</title>
<updated>2017-12-25T13:23:38+00:00</updated>
<author>
<name>Jeffy Chen</name>
<email>jeffy.chen@rock-chips.com</email>
</author>
<published>2017-03-21T07:07:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0f0ac218057f9a08c28083c11dd315ff21686d22'/>
<id>0f0ac218057f9a08c28083c11dd315ff21686d22</id>
<content type='text'>
[ Upstream commit f83bf8da1135ca635aac8f062cad3f001fcf3a26 ]

We have memory leaks of nf_conntrack_helper &amp; expect_policy.

Signed-off-by: Jeffy Chen &lt;jeffy.chen@rock-chips.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit f83bf8da1135ca635aac8f062cad3f001fcf3a26 ]

We have memory leaks of nf_conntrack_helper &amp; expect_policy.

Signed-off-by: Jeffy Chen &lt;jeffy.chen@rock-chips.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nfnl_cthelper: fix runtime expectation policy updates</title>
<updated>2017-12-25T13:23:38+00:00</updated>
<author>
<name>Pablo Neira Ayuso</name>
<email>pablo@netfilter.org</email>
</author>
<published>2017-03-21T12:32:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ec38fb443a091ac99d0d8bc3867db690c8f07fe4'/>
<id>ec38fb443a091ac99d0d8bc3867db690c8f07fe4</id>
<content type='text'>
[ Upstream commit 2c422257550f123049552b39f7af6e3428a60f43 ]

We only allow runtime updates of expectation policies for timeout and
maximum number of expectations, otherwise reject the update.

Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Acked-by: Liping Zhang &lt;zlpnobody@gmail.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit 2c422257550f123049552b39f7af6e3428a60f43 ]

We only allow runtime updates of expectation policies for timeout and
maximum number of expectations, otherwise reject the update.

Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Acked-by: Liping Zhang &lt;zlpnobody@gmail.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: ipvs: Fix inappropriate output of procfs</title>
<updated>2017-12-20T09:07:28+00:00</updated>
<author>
<name>KUWAZAWA Takuya</name>
<email>albatross0@gmail.com</email>
</author>
<published>2017-10-15T11:54:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a463f9c5dfd1bb62f128e6883103117af6f3db1f'/>
<id>a463f9c5dfd1bb62f128e6883103117af6f3db1f</id>
<content type='text'>
[ Upstream commit c5504f724c86ee925e7ffb80aa342cfd57959b13 ]

Information about ipvs in different network namespace can be seen via procfs.

How to reproduce:

  # ip netns add ns01
  # ip netns add ns02
  # ip netns exec ns01 ip a add dev lo 127.0.0.1/8
  # ip netns exec ns02 ip a add dev lo 127.0.0.1/8
  # ip netns exec ns01 ipvsadm -A -t 10.1.1.1:80
  # ip netns exec ns02 ipvsadm -A -t 10.1.1.2:80

The ipvsadm displays information about its own network namespace only.

  # ip netns exec ns01 ipvsadm -Ln
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port           Forward Weight ActiveConn InActConn
  TCP  10.1.1.1:80 wlc

  # ip netns exec ns02 ipvsadm -Ln
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port           Forward Weight ActiveConn InActConn
  TCP  10.1.1.2:80 wlc

But I can see information about other network namespace via procfs.

  # ip netns exec ns01 cat /proc/net/ip_vs
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port Forward Weight ActiveConn InActConn
  TCP  0A010101:0050 wlc
  TCP  0A010102:0050 wlc

  # ip netns exec ns02 cat /proc/net/ip_vs
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port Forward Weight ActiveConn InActConn
  TCP  0A010102:0050 wlc

Signed-off-by: KUWAZAWA Takuya &lt;albatross0@gmail.com&gt;
Acked-by: Julian Anastasov &lt;ja@ssi.bg&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit c5504f724c86ee925e7ffb80aa342cfd57959b13 ]

Information about ipvs in different network namespace can be seen via procfs.

How to reproduce:

  # ip netns add ns01
  # ip netns add ns02
  # ip netns exec ns01 ip a add dev lo 127.0.0.1/8
  # ip netns exec ns02 ip a add dev lo 127.0.0.1/8
  # ip netns exec ns01 ipvsadm -A -t 10.1.1.1:80
  # ip netns exec ns02 ipvsadm -A -t 10.1.1.2:80

The ipvsadm displays information about its own network namespace only.

  # ip netns exec ns01 ipvsadm -Ln
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port           Forward Weight ActiveConn InActConn
  TCP  10.1.1.1:80 wlc

  # ip netns exec ns02 ipvsadm -Ln
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port           Forward Weight ActiveConn InActConn
  TCP  10.1.1.2:80 wlc

But I can see information about other network namespace via procfs.

  # ip netns exec ns01 cat /proc/net/ip_vs
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port Forward Weight ActiveConn InActConn
  TCP  0A010101:0050 wlc
  TCP  0A010102:0050 wlc

  # ip netns exec ns02 cat /proc/net/ip_vs
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
    -&gt; RemoteAddress:Port Forward Weight ActiveConn InActConn
  TCP  0A010102:0050 wlc

Signed-off-by: KUWAZAWA Takuya &lt;albatross0@gmail.com&gt;
Acked-by: Julian Anastasov &lt;ja@ssi.bg&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix handling of verdicts after NF_QUEUE</title>
<updated>2017-12-16T15:25:46+00:00</updated>
<author>
<name>Debabrata Banerjee</name>
<email>dbanerje@akamai.com</email>
</author>
<published>2017-12-13T20:33:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0cab694ab7bca62eb42dbfae209c08edc8d229c4'/>
<id>0cab694ab7bca62eb42dbfae209c08edc8d229c4</id>
<content type='text'>
[This fix is only needed for v4.9 stable since v4.10+ does not have the issue]

A verdict of NF_STOLEN after NF_QUEUE will cause an incorrect return value
and a potential kernel panic via double free of skb's

This was broken by commit 7034b566a4e7 ("netfilter: fix nf_queue handling")
and subsequently fixed in v4.10 by commit c63cbc460419 ("netfilter:
use switch() to handle verdict cases from nf_hook_slow()"). However that
commit cannot be cleanly cherry-picked to v4.9

Signed-off-by: Debabrata Banerjee &lt;dbanerje@akamai.com&gt;
Acked-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[This fix is only needed for v4.9 stable since v4.10+ does not have the issue]

A verdict of NF_STOLEN after NF_QUEUE will cause an incorrect return value
and a potential kernel panic via double free of skb's

This was broken by commit 7034b566a4e7 ("netfilter: fix nf_queue handling")
and subsequently fixed in v4.10 by commit c63cbc460419 ("netfilter:
use switch() to handle verdict cases from nf_hook_slow()"). However that
commit cannot be cleanly cherry-picked to v4.9

Signed-off-by: Debabrata Banerjee &lt;dbanerje@akamai.com&gt;
Acked-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nf_tables: fix oob access</title>
<updated>2017-11-30T08:39:14+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2016-12-13T12:59:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0117c75537cfebc048afed5980246cfd123086f0'/>
<id>0117c75537cfebc048afed5980246cfd123086f0</id>
<content type='text'>
[ Upstream commit 3e38df136e453aa69eb4472108ebce2fb00b1ba6 ]

BUG: KASAN: slab-out-of-bounds in nf_tables_rule_destroy+0xf1/0x130 at addr ffff88006a4c35c8
Read of size 8 by task nft/1607

When we've destroyed last valid expr, nft_expr_next() returns an invalid expr.
We must not dereference it unless it passes != nft_expr_last() check.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit 3e38df136e453aa69eb4472108ebce2fb00b1ba6 ]

BUG: KASAN: slab-out-of-bounds in nf_tables_rule_destroy+0xf1/0x130 at addr ffff88006a4c35c8
Read of size 8 by task nft/1607

When we've destroyed last valid expr, nft_expr_next() returns an invalid expr.
We must not dereference it unless it passes != nft_expr_last() check.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nft_queue: use raw_smp_processor_id()</title>
<updated>2017-11-30T08:39:14+00:00</updated>
<author>
<name>Pablo Neira Ayuso</name>
<email>pablo@netfilter.org</email>
</author>
<published>2016-12-11T19:46:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ea13fd4cdc424dc0da2b0d717308b9f96ada098c'/>
<id>ea13fd4cdc424dc0da2b0d717308b9f96ada098c</id>
<content type='text'>
[ Upstream commit c2e756ff9e699865d294cdc112acfc36419cf5cc ]

Using smp_processor_id() causes splats with PREEMPT_RCU:

[19379.552780] BUG: using smp_processor_id() in preemptible [00000000] code: ping/32389
[19379.552793] caller is debug_smp_processor_id+0x17/0x19
[...]
[19379.552823] Call Trace:
[19379.552832]  [&lt;ffffffff81274e9e&gt;] dump_stack+0x67/0x90
[19379.552837]  [&lt;ffffffff8129a4d4&gt;] check_preemption_disabled+0xe5/0xf5
[19379.552842]  [&lt;ffffffff8129a4fb&gt;] debug_smp_processor_id+0x17/0x19
[19379.552849]  [&lt;ffffffffa07c42dd&gt;] nft_queue_eval+0x35/0x20c [nft_queue]

No need to disable preemption since we only fetch the numeric value, so
let's use raw_smp_processor_id() instead.

Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.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>
[ Upstream commit c2e756ff9e699865d294cdc112acfc36419cf5cc ]

Using smp_processor_id() causes splats with PREEMPT_RCU:

[19379.552780] BUG: using smp_processor_id() in preemptible [00000000] code: ping/32389
[19379.552793] caller is debug_smp_processor_id+0x17/0x19
[...]
[19379.552823] Call Trace:
[19379.552832]  [&lt;ffffffff81274e9e&gt;] dump_stack+0x67/0x90
[19379.552837]  [&lt;ffffffff8129a4d4&gt;] check_preemption_disabled+0xe5/0xf5
[19379.552842]  [&lt;ffffffff8129a4fb&gt;] debug_smp_processor_id+0x17/0x19
[19379.552849]  [&lt;ffffffffa07c42dd&gt;] nft_queue_eval+0x35/0x20c [nft_queue]

No need to disable preemption since we only fetch the numeric value, so
let's use raw_smp_processor_id() instead.

Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nat: Revert "netfilter: nat: convert nat bysrc hash to rhashtable"</title>
<updated>2017-11-18T10:22:24+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2017-09-06T12:39:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a23349bb9f1283e6262c096e7b805168772dd8ca'/>
<id>a23349bb9f1283e6262c096e7b805168772dd8ca</id>
<content type='text'>
commit e1bf1687740ce1a3598a1c5e452b852ff2190682 upstream.

This reverts commit 870190a9ec9075205c0fa795a09fa931694a3ff1.

It was not a good idea. The custom hash table was a much better
fit for this purpose.

A fast lookup is not essential, in fact for most cases there is no lookup
at all because original tuple is not taken and can be used as-is.
What needs to be fast is insertion and deletion.

rhlist removal however requires a rhlist walk.
We can have thousands of entries in such a list if source port/addresses
are reused for multiple flows, if this happens removal requests are so
expensive that deletions of a few thousand flows can take several
seconds(!).

The advantages that we got from rhashtable are:
1) table auto-sizing
2) multiple locks

1) would be nice to have, but it is not essential as we have at
most one lookup per new flow, so even a million flows in the bysource
table are not a problem compared to current deletion cost.
2) is easy to add to custom hash table.

I tried to add hlist_node to rhlist to speed up rhltable_remove but this
isn't doable without changing semantics.  rhltable_remove_fast will
check that the to-be-deleted object is part of the table and that
requires a list walk that we want to avoid.

Furthermore, using hlist_node increases size of struct rhlist_head, which
in turn increases nf_conn size.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821
Reported-by: Ivan Babrou &lt;ibobrik@gmail.com&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.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 e1bf1687740ce1a3598a1c5e452b852ff2190682 upstream.

This reverts commit 870190a9ec9075205c0fa795a09fa931694a3ff1.

It was not a good idea. The custom hash table was a much better
fit for this purpose.

A fast lookup is not essential, in fact for most cases there is no lookup
at all because original tuple is not taken and can be used as-is.
What needs to be fast is insertion and deletion.

rhlist removal however requires a rhlist walk.
We can have thousands of entries in such a list if source port/addresses
are reused for multiple flows, if this happens removal requests are so
expensive that deletions of a few thousand flows can take several
seconds(!).

The advantages that we got from rhashtable are:
1) table auto-sizing
2) multiple locks

1) would be nice to have, but it is not essential as we have at
most one lookup per new flow, so even a million flows in the bysource
table are not a problem compared to current deletion cost.
2) is easy to add to custom hash table.

I tried to add hlist_node to rhlist to speed up rhltable_remove but this
isn't doable without changing semantics.  rhltable_remove_fast will
check that the to-be-deleted object is part of the table and that
requires a list walk that we want to avoid.

Furthermore, using hlist_node increases size of struct rhlist_head, which
in turn increases nf_conn size.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821
Reported-by: Ivan Babrou &lt;ibobrik@gmail.com&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nat: avoid use of nf_conn_nat extension</title>
<updated>2017-11-18T10:22:24+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2017-03-28T08:31:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=25db12f1c584263f96e07cbeec3af75be3416baa'/>
<id>25db12f1c584263f96e07cbeec3af75be3416baa</id>
<content type='text'>
commit 6e699867f84c0f358fed233fe6162173aca28e04 upstream.

successful insert into the bysource hash sets IPS_SRC_NAT_DONE status bit
so we can check that instead of presence of nat extension which requires
extra deref.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.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 6e699867f84c0f358fed233fe6162173aca28e04 upstream.

successful insert into the bysource hash sets IPS_SRC_NAT_DONE status bit
so we can check that instead of presence of nat extension which requires
extra deref.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
