<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/net/ipv6, branch v4.9.89</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: x_tables: pack percpu counter allocations</title>
<updated>2018-03-18T10:18:54+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2016-11-22T13:44:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=db6a0cbeb940898dd56167241f68972b50890566'/>
<id>db6a0cbeb940898dd56167241f68972b50890566</id>
<content type='text'>
commit ae0ac0ed6fcf5af3be0f63eb935f483f44a402d2 upstream.

instead of allocating each xt_counter individually, allocate 4k chunks
and then use these for counter allocation requests.

This should speed up rule evaluation by increasing data locality,
also speeds up ruleset loading because we reduce calls to the percpu
allocator.

As Eric points out we can't use PAGE_SIZE, page_allocator would fail on
arches with 64k page size.

Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&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 ae0ac0ed6fcf5af3be0f63eb935f483f44a402d2 upstream.

instead of allocating each xt_counter individually, allocate 4k chunks
and then use these for counter allocation requests.

This should speed up rule evaluation by increasing data locality,
also speeds up ruleset loading because we reduce calls to the percpu
allocator.

As Eric points out we can't use PAGE_SIZE, page_allocator would fail on
arches with 64k page size.

Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&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: x_tables: pass xt_counters struct to counter allocator</title>
<updated>2018-03-18T10:18:54+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2016-11-22T13:44:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=dac4448faf499b2597536aecfdb46eeace17a243'/>
<id>dac4448faf499b2597536aecfdb46eeace17a243</id>
<content type='text'>
commit f28e15bacedd444608e25421c72eb2cf4527c9ca upstream.

Keeps some noise away from a followup patch.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&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 f28e15bacedd444608e25421c72eb2cf4527c9ca upstream.

Keeps some noise away from a followup patch.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&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: x_tables: pass xt_counters struct instead of packet counter</title>
<updated>2018-03-18T10:18:54+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2016-11-22T13:44:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=61346e20c0017abf77bd133f80c35ca9224fbd96'/>
<id>61346e20c0017abf77bd133f80c35ca9224fbd96</id>
<content type='text'>
commit 4d31eef5176df06f218201bc9c0ce40babb41660 upstream.

On SMP we overload the packet counter (unsigned long) to contain
percpu offset.  Hide this from callers and pass xt_counters address
instead.

Preparation patch to allocate the percpu counters in page-sized batch
chunks.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&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 4d31eef5176df06f218201bc9c0ce40babb41660 upstream.

On SMP we overload the packet counter (unsigned long) to contain
percpu offset.  Hide this from callers and pass xt_counters address
instead.

Preparation patch to allocate the percpu counters in page-sized batch
chunks.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&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: ipv6: fix use-after-free Write in nf_nat_ipv6_manip_pkt</title>
<updated>2018-03-18T10:18:54+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2018-02-19T07:10:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=60962e98c38a563b22df67b3e55fd88837d53b83'/>
<id>60962e98c38a563b22df67b3e55fd88837d53b83</id>
<content type='text'>
commit b078556aecd791b0e5cb3a59f4c3a14273b52121 upstream.

l4proto-&gt;manip_pkt() can cause reallocation of skb head so pointer
to the ipv6 header must be reloaded.

Reported-and-tested-by: &lt;syzbot+10005f4292fc9cc89de7@syzkaller.appspotmail.com&gt;
Fixes: 58a317f1061c89 ("netfilter: ipv6: add IPv6 NAT support")
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 b078556aecd791b0e5cb3a59f4c3a14273b52121 upstream.

l4proto-&gt;manip_pkt() can cause reallocation of skb head so pointer
to the ipv6 header must be reloaded.

Reported-and-tested-by: &lt;syzbot+10005f4292fc9cc89de7@syzkaller.appspotmail.com&gt;
Fixes: 58a317f1061c89 ("netfilter: ipv6: add IPv6 NAT support")
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: add back stackpointer size checks</title>
<updated>2018-03-18T10:18:53+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2018-02-07T12:46:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f506da51bdf6602ec942f25d682a4de9b59760da'/>
<id>f506da51bdf6602ec942f25d682a4de9b59760da</id>
<content type='text'>
commit 57ebd808a97d7c5b1e1afb937c2db22beba3c1f8 upstream.

The rationale for removing the check is only correct for rulesets
generated by ip(6)tables.

In iptables, a jump can only occur to a user-defined chain, i.e.
because we size the stack based on number of user-defined chains we
cannot exceed stack size.

However, the underlying binary format has no such restriction,
and the validation step only ensures that the jump target is a
valid rule start point.

IOW, its possible to build a rule blob that has no user-defined
chains but does contain a jump.

If this happens, no jump stack gets allocated and crash occurs
because no jumpstack was allocated.

Fixes: 7814b6ec6d0d6 ("netfilter: xtables: don't save/restore jumpstack offset")
Reported-by: syzbot+e783f671527912cd9403@syzkaller.appspotmail.com
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 57ebd808a97d7c5b1e1afb937c2db22beba3c1f8 upstream.

The rationale for removing the check is only correct for rulesets
generated by ip(6)tables.

In iptables, a jump can only occur to a user-defined chain, i.e.
because we size the stack based on number of user-defined chains we
cannot exceed stack size.

However, the underlying binary format has no such restriction,
and the validation step only ensures that the jump target is a
valid rule start point.

IOW, its possible to build a rule blob that has no user-defined
chains but does contain a jump.

If this happens, no jump stack gets allocated and crash occurs
because no jumpstack was allocated.

Fixes: 7814b6ec6d0d6 ("netfilter: xtables: don't save/restore jumpstack offset")
Reported-by: syzbot+e783f671527912cd9403@syzkaller.appspotmail.com
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>udplite: fix partial checksum initialization</title>
<updated>2018-03-11T15:21:32+00:00</updated>
<author>
<name>Alexey Kodanev</name>
<email>alexey.kodanev@oracle.com</email>
</author>
<published>2018-02-15T17:18:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5984901390079ef0c393cbd4db96392c0af7db9f'/>
<id>5984901390079ef0c393cbd4db96392c0af7db9f</id>
<content type='text'>
[ Upstream commit 15f35d49c93f4fa9875235e7bf3e3783d2dd7a1b ]

Since UDP-Lite is always using checksum, the following path is
triggered when calculating pseudo header for it:

  udp4_csum_init() or udp6_csum_init()
    skb_checksum_init_zero_check()
      __skb_checksum_validate_complete()

The problem can appear if skb-&gt;len is less than CHECKSUM_BREAK. In
this particular case __skb_checksum_validate_complete() also invokes
__skb_checksum_complete(skb). If UDP-Lite is using partial checksum
that covers only part of a packet, the function will return bad
checksum and the packet will be dropped.

It can be fixed if we skip skb_checksum_init_zero_check() and only
set the required pseudo header checksum for UDP-Lite with partial
checksum before udp4_csum_init()/udp6_csum_init() functions return.

Fixes: ed70fcfcee95 ("net: Call skb_checksum_init in IPv4")
Fixes: e4f45b7f40bd ("net: Call skb_checksum_init in IPv6")
Signed-off-by: Alexey Kodanev &lt;alexey.kodanev@oracle.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>
[ Upstream commit 15f35d49c93f4fa9875235e7bf3e3783d2dd7a1b ]

Since UDP-Lite is always using checksum, the following path is
triggered when calculating pseudo header for it:

  udp4_csum_init() or udp6_csum_init()
    skb_checksum_init_zero_check()
      __skb_checksum_validate_complete()

The problem can appear if skb-&gt;len is less than CHECKSUM_BREAK. In
this particular case __skb_checksum_validate_complete() also invokes
__skb_checksum_complete(skb). If UDP-Lite is using partial checksum
that covers only part of a packet, the function will return bad
checksum and the packet will be dropped.

It can be fixed if we skip skb_checksum_init_zero_check() and only
set the required pseudo header checksum for UDP-Lite with partial
checksum before udp4_csum_init()/udp6_csum_init() functions return.

Fixes: ed70fcfcee95 ("net: Call skb_checksum_init in IPv4")
Fixes: e4f45b7f40bd ("net: Call skb_checksum_init in IPv6")
Signed-off-by: Alexey Kodanev &lt;alexey.kodanev@oracle.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>
<entry>
<title>ipv6 sit: work around bogus gcc-8 -Wrestrict warning</title>
<updated>2018-03-11T15:21:31+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2018-02-22T15:55:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c9a3046de72a9eb8fabe70ad3f1f0751152e9be6'/>
<id>c9a3046de72a9eb8fabe70ad3f1f0751152e9be6</id>
<content type='text'>
[ Upstream commit ca79bec237f5809a7c3c59bd41cd0880aa889966 ]

gcc-8 has a new warning that detects overlapping input and output arguments
in memcpy(). It triggers for sit_init_net() calling ipip6_tunnel_clone_6rd(),
which is actually correct:

net/ipv6/sit.c: In function 'sit_init_net':
net/ipv6/sit.c:192:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]

The problem here is that the logic detecting the memcpy() arguments finds them
to be the same, but the conditional that tests for the input and output of
ipip6_tunnel_clone_6rd() to be identical is not a compile-time constant.

We know that netdev_priv(t-&gt;dev) is the same as t for a tunnel device,
and comparing "dev" directly here lets the compiler figure out as well
that 'dev == sitn-&gt;fb_tunnel_dev' when called from sit_init_net(), so
it no longer warns.

This code is old, so Cc stable to make sure that we don't get the warning
for older kernels built with new gcc.

Cc: Martin Sebor &lt;msebor@gmail.com&gt;
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83456
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&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>
[ Upstream commit ca79bec237f5809a7c3c59bd41cd0880aa889966 ]

gcc-8 has a new warning that detects overlapping input and output arguments
in memcpy(). It triggers for sit_init_net() calling ipip6_tunnel_clone_6rd(),
which is actually correct:

net/ipv6/sit.c: In function 'sit_init_net':
net/ipv6/sit.c:192:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]

The problem here is that the logic detecting the memcpy() arguments finds them
to be the same, but the conditional that tests for the input and output of
ipip6_tunnel_clone_6rd() to be identical is not a compile-time constant.

We know that netdev_priv(t-&gt;dev) is the same as t for a tunnel device,
and comparing "dev" directly here lets the compiler figure out as well
that 'dev == sitn-&gt;fb_tunnel_dev' when called from sit_init_net(), so
it no longer warns.

This code is old, so Cc stable to make sure that we don't get the warning
for older kernels built with new gcc.

Cc: Martin Sebor &lt;msebor@gmail.com&gt;
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83456
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&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>ip6_tunnel: get the min mtu properly in ip6_tnl_xmit</title>
<updated>2018-03-03T09:23:23+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2017-12-18T06:26:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1148fee2173c03718b1f3ce47d67eb09c165368f'/>
<id>1148fee2173c03718b1f3ce47d67eb09c165368f</id>
<content type='text'>
[ Upstream commit c9fefa08190fc879fb2e681035d7774e0a8c5170 ]

Now it's using IPV6_MIN_MTU as the min mtu in ip6_tnl_xmit, but
IPV6_MIN_MTU actually only works when the inner packet is ipv6.

With IPV6_MIN_MTU for ipv4 packets, the new pmtu for inner dst
couldn't be set less than 1280. It would cause tx_err and the
packet to be dropped when the outer dst pmtu is close to 1280.

Jianlin found it by running ipv4 traffic with the topo:

  (client) gre6 &lt;---&gt; eth1 (route) eth2 &lt;---&gt; gre6 (server)

After changing eth2 mtu to 1300, the performance became very
low, or the connection was even broken. The issue also affects
ip4ip6 and ip6ip6 tunnels.

So if the inner packet is ipv4, 576 should be considered as the
min mtu.

Note that for ip4ip6 and ip6ip6 tunnels, the inner packet can
only be ipv4 or ipv6, but for gre6 tunnel, it may also be ARP.
This patch using 576 as the min mtu for non-ipv6 packet works
for all those cases.

Reported-by: Jianlin Shi &lt;jishi@redhat.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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 c9fefa08190fc879fb2e681035d7774e0a8c5170 ]

Now it's using IPV6_MIN_MTU as the min mtu in ip6_tnl_xmit, but
IPV6_MIN_MTU actually only works when the inner packet is ipv6.

With IPV6_MIN_MTU for ipv4 packets, the new pmtu for inner dst
couldn't be set less than 1280. It would cause tx_err and the
packet to be dropped when the outer dst pmtu is close to 1280.

Jianlin found it by running ipv4 traffic with the topo:

  (client) gre6 &lt;---&gt; eth1 (route) eth2 &lt;---&gt; gre6 (server)

After changing eth2 mtu to 1300, the performance became very
low, or the connection was even broken. The issue also affects
ip4ip6 and ip6ip6 tunnels.

So if the inner packet is ipv4, 576 should be considered as the
min mtu.

Note that for ip4ip6 and ip6ip6 tunnels, the inner packet can
only be ipv4 or ipv6, but for gre6 tunnel, it may also be ARP.
This patch using 576 as the min mtu for non-ipv6 packet works
for all those cases.

Reported-by: Jianlin Shi &lt;jishi@redhat.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: icmp6: Allow icmp messages to be looped back</title>
<updated>2018-03-03T09:23:21+00:00</updated>
<author>
<name>Brendan McGrath</name>
<email>redmcg@redmandi.dyndns.org</email>
</author>
<published>2017-12-13T11:14:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3cf31f5b38ed1d78d39e9fb1d460c4684690ec1e'/>
<id>3cf31f5b38ed1d78d39e9fb1d460c4684690ec1e</id>
<content type='text'>
[ Upstream commit 588753f1eb18978512b1c9b85fddb457d46f9033 ]

One example of when an ICMPv6 packet is required to be looped back is
when a host acts as both a Multicast Listener and a Multicast Router.

A Multicast Router will listen on address ff02::16 for MLDv2 messages.

Currently, MLDv2 messages originating from a Multicast Listener running
on the same host as the Multicast Router are not being delivered to the
Multicast Router. This is due to dst.input being assigned the default
value of dst_discard.

This results in the packet being looped back but discarded before being
delivered to the Multicast Router.

This patch sets dst.input to ip6_input to ensure a looped back packet
is delivered to the Multicast Router.

Signed-off-by: Brendan McGrath &lt;redmcg@redmandi.dyndns.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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 588753f1eb18978512b1c9b85fddb457d46f9033 ]

One example of when an ICMPv6 packet is required to be looped back is
when a host acts as both a Multicast Listener and a Multicast Router.

A Multicast Router will listen on address ff02::16 for MLDv2 messages.

Currently, MLDv2 messages originating from a Multicast Listener running
on the same host as the Multicast Router are not being delivered to the
Multicast Router. This is due to dst.input being assigned the default
value of dst_discard.

This results in the packet being looped back but discarded before being
delivered to the Multicast Router.

This patch sets dst.input to ip6_input to ensure a looped back packet
is delivered to the Multicast Router.

Signed-off-by: Brendan McGrath &lt;redmcg@redmandi.dyndns.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: drop outermost socket lock in getsockopt()</title>
<updated>2018-02-28T09:18:30+00:00</updated>
<author>
<name>Paolo Abeni</name>
<email>pabeni@redhat.com</email>
</author>
<published>2018-02-08T11:19:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d58d78c207a348a87cb143dadcbf839ea35443b6'/>
<id>d58d78c207a348a87cb143dadcbf839ea35443b6</id>
<content type='text'>
commit 01ea306f2ac2baff98d472da719193e738759d93 upstream.

The Syzbot reported a possible deadlock in the netfilter area caused by
rtnl lock, xt lock and socket lock being acquired with a different order
on different code paths, leading to the following backtrace:
Reviewed-by: Xin Long &lt;lucien.xin@gmail.com&gt;

======================================================
WARNING: possible circular locking dependency detected
4.15.0+ #301 Not tainted
------------------------------------------------------
syzkaller233489/4179 is trying to acquire lock:
  (rtnl_mutex){+.+.}, at: [&lt;0000000048e996fd&gt;] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

but task is already holding lock:
  (&amp;xt[i].mutex){+.+.}, at: [&lt;00000000328553a2&gt;]
xt_find_table_lock+0x3e/0x3e0 net/netfilter/x_tables.c:1041

which lock already depends on the new lock.
===

Since commit 3f34cfae1230 ("netfilter: on sockopt() acquire sock lock
only in the required scope"), we already acquire the socket lock in
the innermost scope, where needed. In such commit I forgot to remove
the outer-most socket lock from the getsockopt() path, this commit
addresses the issues dropping it now.

v1 -&gt; v2: fix bad subj, added relavant 'fixes' tag

Fixes: 22265a5c3c10 ("netfilter: xt_TEE: resolve oif using netdevice notifiers")
Fixes: 202f59afd441 ("netfilter: ipt_CLUSTERIP: do not hold dev")
Fixes: 3f34cfae1230 ("netfilter: on sockopt() acquire sock lock only in the required scope")
Reported-by: syzbot+ddde1c7b7ff7442d7f2d@syzkaller.appspotmail.com
Suggested-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Tested-by: Krzysztof Piotr Oledzki &lt;ole@ans.pl&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 01ea306f2ac2baff98d472da719193e738759d93 upstream.

The Syzbot reported a possible deadlock in the netfilter area caused by
rtnl lock, xt lock and socket lock being acquired with a different order
on different code paths, leading to the following backtrace:
Reviewed-by: Xin Long &lt;lucien.xin@gmail.com&gt;

======================================================
WARNING: possible circular locking dependency detected
4.15.0+ #301 Not tainted
------------------------------------------------------
syzkaller233489/4179 is trying to acquire lock:
  (rtnl_mutex){+.+.}, at: [&lt;0000000048e996fd&gt;] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

but task is already holding lock:
  (&amp;xt[i].mutex){+.+.}, at: [&lt;00000000328553a2&gt;]
xt_find_table_lock+0x3e/0x3e0 net/netfilter/x_tables.c:1041

which lock already depends on the new lock.
===

Since commit 3f34cfae1230 ("netfilter: on sockopt() acquire sock lock
only in the required scope"), we already acquire the socket lock in
the innermost scope, where needed. In such commit I forgot to remove
the outer-most socket lock from the getsockopt() path, this commit
addresses the issues dropping it now.

v1 -&gt; v2: fix bad subj, added relavant 'fixes' tag

Fixes: 22265a5c3c10 ("netfilter: xt_TEE: resolve oif using netdevice notifiers")
Fixes: 202f59afd441 ("netfilter: ipt_CLUSTERIP: do not hold dev")
Fixes: 3f34cfae1230 ("netfilter: on sockopt() acquire sock lock only in the required scope")
Reported-by: syzbot+ddde1c7b7ff7442d7f2d@syzkaller.appspotmail.com
Suggested-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Tested-by: Krzysztof Piotr Oledzki &lt;ole@ans.pl&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

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