<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/net/netfilter, branch v4.9.71</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>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.toradex.cn/cgit/linux-toradex.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.toradex.cn/cgit/linux-toradex.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.toradex.cn/cgit/linux-toradex.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.toradex.cn/cgit/linux-toradex.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.toradex.cn/cgit/linux-toradex.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.toradex.cn/cgit/linux-toradex.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>
<entry>
<title>netfilter: nft_meta: deal with PACKET_LOOPBACK in netdev family</title>
<updated>2017-11-15T14:53:15+00:00</updated>
<author>
<name>Liping Zhang</name>
<email>zlpnobody@gmail.com</email>
</author>
<published>2017-01-07T13:33:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c5493c6e4a6ac9f0ce5bd95ea16d2867d1c89c76'/>
<id>c5493c6e4a6ac9f0ce5bd95ea16d2867d1c89c76</id>
<content type='text'>
[ Upstream commit f169fd695b192dd7b23aff8e69d25a1bc881bbfa ]

After adding the following nft rule, then ping 224.0.0.1:
  # nft add rule netdev t c pkttype host counter

The warning complain message will be printed out again and again:
  WARNING: CPU: 0 PID: 10182 at net/netfilter/nft_meta.c:163 \
           nft_meta_get_eval+0x3fe/0x460 [nft_meta]
  [...]
  Call Trace:
  &lt;IRQ&gt;
  dump_stack+0x85/0xc2
  __warn+0xcb/0xf0
  warn_slowpath_null+0x1d/0x20
  nft_meta_get_eval+0x3fe/0x460 [nft_meta]
  nft_do_chain+0xff/0x5e0 [nf_tables]

So we should deal with PACKET_LOOPBACK in netdev family too. For ipv4,
convert it to PACKET_BROADCAST/MULTICAST according to the destination
address's type; For ipv6, convert it to PACKET_MULTICAST directly.

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 f169fd695b192dd7b23aff8e69d25a1bc881bbfa ]

After adding the following nft rule, then ping 224.0.0.1:
  # nft add rule netdev t c pkttype host counter

The warning complain message will be printed out again and again:
  WARNING: CPU: 0 PID: 10182 at net/netfilter/nft_meta.c:163 \
           nft_meta_get_eval+0x3fe/0x460 [nft_meta]
  [...]
  Call Trace:
  &lt;IRQ&gt;
  dump_stack+0x85/0xc2
  __warn+0xcb/0xf0
  warn_slowpath_null+0x1d/0x20
  nft_meta_get_eval+0x3fe/0x460 [nft_meta]
  nft_do_chain+0xff/0x5e0 [nf_tables]

So we should deal with PACKET_LOOPBACK in netdev family too. For ipv4,
convert it to PACKET_BROADCAST/MULTICAST according to the destination
address's type; For ipv6, convert it to PACKET_MULTICAST directly.

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: nf_ct_expect: Change __nf_ct_expect_check() return value.</title>
<updated>2017-10-21T15:21:34+00:00</updated>
<author>
<name>Jarno Rajahalme</name>
<email>jarno@ovn.org</email>
</author>
<published>2017-02-24T01:08:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f107c6ddf8db81bda0f784c57c9d26ca87cc3c38'/>
<id>f107c6ddf8db81bda0f784c57c9d26ca87cc3c38</id>
<content type='text'>
[ Upstream commit 4b86c459c7bee3acaf92f0e2b4c6ac803eaa1a58 ]

Commit 4dee62b1b9b4 ("netfilter: nf_ct_expect: nf_ct_expect_insert()
returns void") inadvertently changed the successful return value of
nf_ct_expect_related_report() from 0 to 1 due to
__nf_ct_expect_check() returning 1 on success.  Prevent this
regression in the future by changing the return value of
__nf_ct_expect_check() to 0 on success.

Signed-off-by: Jarno Rajahalme &lt;jarno@ovn.org&gt;
Acked-by: Joe Stringer &lt;joe@ovn.org&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 4b86c459c7bee3acaf92f0e2b4c6ac803eaa1a58 ]

Commit 4dee62b1b9b4 ("netfilter: nf_ct_expect: nf_ct_expect_insert()
returns void") inadvertently changed the successful return value of
nf_ct_expect_related_report() from 0 to 1 due to
__nf_ct_expect_check() returning 1 on success.  Prevent this
regression in the future by changing the return value of
__nf_ct_expect_check() to 0 on success.

Signed-off-by: Jarno Rajahalme &lt;jarno@ovn.org&gt;
Acked-by: Joe Stringer &lt;joe@ovn.org&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 incorrect helper-&gt;expect_class_max</title>
<updated>2017-10-08T08:26:10+00:00</updated>
<author>
<name>Liping Zhang</name>
<email>zlpnobody@gmail.com</email>
</author>
<published>2017-03-19T14:35:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=cd402b889606ed9b51d76594ddd059a8be6356a1'/>
<id>cd402b889606ed9b51d76594ddd059a8be6356a1</id>
<content type='text'>
[ Upstream commit ae5c682113f9f94cc5e76f92cf041ee624c173ee ]

The helper-&gt;expect_class_max must be set to the total number of
expect_policy minus 1, since we will use the statement "if (class &gt;
helper-&gt;expect_class_max)" to validate the CTA_EXPECT_CLASS attr in
ctnetlink_alloc_expect.

So for compatibility, set the helper-&gt;expect_class_max to the
NFCTH_POLICY_SET_NUM attr's value minus 1.

Also: it's invalid when the NFCTH_POLICY_SET_NUM attr's value is zero.
1. this will result "expect_policy = kzalloc(0, GFP_KERNEL);";
2. we cannot set the helper-&gt;expect_class_max to a proper value.

So if nla_get_be32(tb[NFCTH_POLICY_SET_NUM]) is zero, report -EINVAL to
the userspace.

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 ae5c682113f9f94cc5e76f92cf041ee624c173ee ]

The helper-&gt;expect_class_max must be set to the total number of
expect_policy minus 1, since we will use the statement "if (class &gt;
helper-&gt;expect_class_max)" to validate the CTA_EXPECT_CLASS attr in
ctnetlink_alloc_expect.

So for compatibility, set the helper-&gt;expect_class_max to the
NFCTH_POLICY_SET_NUM attr's value minus 1.

Also: it's invalid when the NFCTH_POLICY_SET_NUM attr's value is zero.
1. this will result "expect_policy = kzalloc(0, GFP_KERNEL);";
2. we cannot set the helper-&gt;expect_class_max to a proper value.

So if nla_get_be32(tb[NFCTH_POLICY_SET_NUM]) is zero, report -EINVAL to
the userspace.

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: invoke synchronize_rcu after set the _hook_ to NULL</title>
<updated>2017-10-08T08:26:09+00:00</updated>
<author>
<name>Liping Zhang</name>
<email>zlpnobody@gmail.com</email>
</author>
<published>2017-03-25T00:53:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=146561a3f1c8d7f9ef9b77964c846da48c62a6ac'/>
<id>146561a3f1c8d7f9ef9b77964c846da48c62a6ac</id>
<content type='text'>
[ Upstream commit 3b7dabf029478bb80507a6c4500ca94132a2bc0b ]

Otherwise, another CPU may access the invalid pointer. For example:
    CPU0                CPU1
     -              rcu_read_lock();
     -              pfunc = _hook_;
  _hook_ = NULL;          -
  mod unload              -
     -                 pfunc(); // invalid, panic
     -             rcu_read_unlock();

So we must call synchronize_rcu() to wait the rcu reader to finish.

Also note, in nf_nat_snmp_basic_fini, synchronize_rcu() will be invoked
by later nf_conntrack_helper_unregister, but I'm inclined to add a
explicit synchronize_rcu after set the nf_nat_snmp_hook to NULL. Depend
on such obscure assumptions is not a good idea.

Last, in nfnetlink_cttimeout, we use kfree_rcu to free the time object,
so in cttimeout_exit, invoking rcu_barrier() is not necessary at all,
remove it too.

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 3b7dabf029478bb80507a6c4500ca94132a2bc0b ]

Otherwise, another CPU may access the invalid pointer. For example:
    CPU0                CPU1
     -              rcu_read_lock();
     -              pfunc = _hook_;
  _hook_ = NULL;          -
  mod unload              -
     -                 pfunc(); // invalid, panic
     -             rcu_read_unlock();

So we must call synchronize_rcu() to wait the rcu reader to finish.

Also note, in nf_nat_snmp_basic_fini, synchronize_rcu() will be invoked
by later nf_conntrack_helper_unregister, but I'm inclined to add a
explicit synchronize_rcu after set the nf_nat_snmp_hook to NULL. Depend
on such obscure assumptions is not a good idea.

Last, in nfnetlink_cttimeout, we use kfree_rcu to free the time object,
so in cttimeout_exit, invoking rcu_barrier() is not necessary at all,
remove it too.

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>
</feed>
