<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include/net, branch v4.9.76</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>tcp: invalidate rate samples during SACK reneging</title>
<updated>2018-01-02T19:35:13+00:00</updated>
<author>
<name>Yousuk Seung</name>
<email>ysseung@google.com</email>
</author>
<published>2017-12-07T21:41:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e74fe7268e7eadb2880d3842fe167131220d5616'/>
<id>e74fe7268e7eadb2880d3842fe167131220d5616</id>
<content type='text'>
[ Upstream commit d4761754b4fb2ef8d9a1e9d121c4bec84e1fe292 ]

Mark tcp_sock during a SACK reneging event and invalidate rate samples
while marked. Such rate samples may overestimate bw by including packets
that were SACKed before reneging.

&lt; ack 6001 win 10000 sack 7001:38001
&lt; ack 7001 win 0 sack 8001:38001 // Reneg detected
&gt; seq 7001:8001 // RTO, SACK cleared.
&lt; ack 38001 win 10000

In above example the rate sample taken after the last ack will count
7001-38001 as delivered while the actual delivery rate likely could
be much lower i.e. 7001-8001.

This patch adds a new field tcp_sock.sack_reneg and marks it when we
declare SACK reneging and entering TCP_CA_Loss, and unmarks it after
the last rate sample was taken before moving back to TCP_CA_Open. This
patch also invalidates rate samples taken while tcp_sock.is_sack_reneg
is set.

Fixes: b9f64820fb22 ("tcp: track data delivery rate for a TCP connection")
Signed-off-by: Yousuk Seung &lt;ysseung@google.com&gt;
Signed-off-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Acked-by: Priyaranjan Jha &lt;priyarjha@google.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 d4761754b4fb2ef8d9a1e9d121c4bec84e1fe292 ]

Mark tcp_sock during a SACK reneging event and invalidate rate samples
while marked. Such rate samples may overestimate bw by including packets
that were SACKed before reneging.

&lt; ack 6001 win 10000 sack 7001:38001
&lt; ack 7001 win 0 sack 8001:38001 // Reneg detected
&gt; seq 7001:8001 // RTO, SACK cleared.
&lt; ack 38001 win 10000

In above example the rate sample taken after the last ack will count
7001-38001 as delivered while the actual delivery rate likely could
be much lower i.e. 7001-8001.

This patch adds a new field tcp_sock.sack_reneg and marks it when we
declare SACK reneging and entering TCP_CA_Loss, and unmarks it after
the last rate sample was taken before moving back to TCP_CA_Open. This
patch also invalidates rate samples taken while tcp_sock.is_sack_reneg
is set.

Fixes: b9f64820fb22 ("tcp: track data delivery rate for a TCP connection")
Signed-off-by: Yousuk Seung &lt;ysseung@google.com&gt;
Signed-off-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Acked-by: Priyaranjan Jha &lt;priyarjha@google.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>ipv4: igmp: guard against silly MTU values</title>
<updated>2018-01-02T19:35:10+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2017-12-11T15:17:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c2f78bf8ca3aa18e51f1de41093db5adae2c5f34'/>
<id>c2f78bf8ca3aa18e51f1de41093db5adae2c5f34</id>
<content type='text'>
[ Upstream commit b5476022bbada3764609368f03329ca287528dc8 ]

IPv4 stack reacts to changes to small MTU, by disabling itself under
RTNL.

But there is a window where threads not using RTNL can see a wrong
device mtu. This can lead to surprises, in igmp code where it is
assumed the mtu is suitable.

Fix this by reading device mtu once and checking IPv4 minimal MTU.

This patch adds missing IPV4_MIN_MTU define, to not abuse
ETH_MIN_MTU anymore.

Signed-off-by: Eric Dumazet &lt;edumazet@google.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 b5476022bbada3764609368f03329ca287528dc8 ]

IPv4 stack reacts to changes to small MTU, by disabling itself under
RTNL.

But there is a window where threads not using RTNL can see a wrong
device mtu. This can lead to surprises, in igmp code where it is
assumed the mtu is suitable.

Fix this by reading device mtu once and checking IPv4 minimal MTU.

This patch adds missing IPV4_MIN_MTU define, to not abuse
ETH_MIN_MTU anymore.

Signed-off-by: Eric Dumazet &lt;edumazet@google.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>vhost-vsock: add pkt cancel capability</title>
<updated>2017-12-25T13:23:37+00:00</updated>
<author>
<name>Peng Tao</name>
<email>bergwolf@gmail.com</email>
</author>
<published>2017-03-15T01:32:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=482b3f92aea249b031ba0bc24df73f3c48f1f5c2'/>
<id>482b3f92aea249b031ba0bc24df73f3c48f1f5c2</id>
<content type='text'>
[ Upstream commit 16320f363ae128d9b9c70e60f00f2a572f57c23d ]

To allow canceling all packets of a connection.

Reviewed-by: Stefan Hajnoczi &lt;stefanha@redhat.com&gt;
Reviewed-by: Jorgen Hansen &lt;jhansen@vmware.com&gt;
Signed-off-by: Peng Tao &lt;bergwolf@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&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 16320f363ae128d9b9c70e60f00f2a572f57c23d ]

To allow canceling all packets of a connection.

Reviewed-by: Stefan Hajnoczi &lt;stefanha@redhat.com&gt;
Reviewed-by: Jorgen Hansen &lt;jhansen@vmware.com&gt;
Signed-off-by: Peng Tao &lt;bergwolf@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&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>net: remove hlist_nulls_add_tail_rcu()</title>
<updated>2017-12-16T15:25:45+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2017-12-05T20:45:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=564fe3e0e95e0b800ca376ec5c0f20c578494234'/>
<id>564fe3e0e95e0b800ca376ec5c0f20c578494234</id>
<content type='text'>
[ Upstream commit d7efc6c11b277d9d80b99b1334a78bfe7d7edf10 ]

Alexander Potapenko reported use of uninitialized memory [1]

This happens when inserting a request socket into TCP ehash,
in __sk_nulls_add_node_rcu(), since sk_reuseport is not initialized.

Bug was added by commit d894ba18d4e4 ("soreuseport: fix ordering for
mixed v4/v6 sockets")

Note that d296ba60d8e2 ("soreuseport: Resolve merge conflict for v4/v6
ordering fix") missed the opportunity to get rid of
hlist_nulls_add_tail_rcu() :

Both UDP sockets and TCP/DCCP listeners no longer use
__sk_nulls_add_node_rcu() for their hash insertion.

Since all other sockets have unique 4-tuple, the reuseport status
has no special meaning, so we can always use hlist_nulls_add_head_rcu()
for them and save few cycles/instructions.

[1]

==================================================================
BUG: KMSAN: use of uninitialized memory in inet_ehash_insert+0xd40/0x1050
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.13.0+ #3288
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 &lt;IRQ&gt;
 __dump_stack lib/dump_stack.c:16
 dump_stack+0x185/0x1d0 lib/dump_stack.c:52
 kmsan_report+0x13f/0x1c0 mm/kmsan/kmsan.c:1016
 __msan_warning_32+0x69/0xb0 mm/kmsan/kmsan_instr.c:766
 __sk_nulls_add_node_rcu ./include/net/sock.h:684
 inet_ehash_insert+0xd40/0x1050 net/ipv4/inet_hashtables.c:413
 reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:754
 inet_csk_reqsk_queue_hash_add+0x1cc/0x300 net/ipv4/inet_connection_sock.c:765
 tcp_conn_request+0x31e7/0x36f0 net/ipv4/tcp_input.c:6414
 tcp_v4_conn_request+0x16d/0x220 net/ipv4/tcp_ipv4.c:1314
 tcp_rcv_state_process+0x42a/0x7210 net/ipv4/tcp_input.c:5917
 tcp_v4_do_rcv+0xa6a/0xcd0 net/ipv4/tcp_ipv4.c:1483
 tcp_v4_rcv+0x3de0/0x4ab0 net/ipv4/tcp_ipv4.c:1763
 ip_local_deliver_finish+0x6bb/0xcb0 net/ipv4/ip_input.c:216
 NF_HOOK ./include/linux/netfilter.h:248
 ip_local_deliver+0x3fa/0x480 net/ipv4/ip_input.c:257
 dst_input ./include/net/dst.h:477
 ip_rcv_finish+0x6fb/0x1540 net/ipv4/ip_input.c:397
 NF_HOOK ./include/linux/netfilter.h:248
 ip_rcv+0x10f6/0x15c0 net/ipv4/ip_input.c:488
 __netif_receive_skb_core+0x36f6/0x3f60 net/core/dev.c:4298
 __netif_receive_skb net/core/dev.c:4336
 netif_receive_skb_internal+0x63c/0x19c0 net/core/dev.c:4497
 napi_skb_finish net/core/dev.c:4858
 napi_gro_receive+0x629/0xa50 net/core/dev.c:4889
 e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4018
 e1000_clean_rx_irq+0x1492/0x1d30
drivers/net/ethernet/intel/e1000/e1000_main.c:4474
 e1000_clean+0x43aa/0x5970 drivers/net/ethernet/intel/e1000/e1000_main.c:3819
 napi_poll net/core/dev.c:5500
 net_rx_action+0x73c/0x1820 net/core/dev.c:5566
 __do_softirq+0x4b4/0x8dd kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364
 irq_exit+0x203/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 ./arch/x86/include/asm/apic.h:638
 do_IRQ+0x15e/0x1a0 arch/x86/kernel/irq.c:263
 common_interrupt+0x86/0x86

Fixes: d894ba18d4e4 ("soreuseport: fix ordering for mixed v4/v6 sockets")
Fixes: d296ba60d8e2 ("soreuseport: Resolve merge conflict for v4/v6 ordering fix")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Alexander Potapenko &lt;glider@google.com&gt;
Acked-by: Craig Gallek &lt;kraig@google.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 d7efc6c11b277d9d80b99b1334a78bfe7d7edf10 ]

Alexander Potapenko reported use of uninitialized memory [1]

This happens when inserting a request socket into TCP ehash,
in __sk_nulls_add_node_rcu(), since sk_reuseport is not initialized.

Bug was added by commit d894ba18d4e4 ("soreuseport: fix ordering for
mixed v4/v6 sockets")

Note that d296ba60d8e2 ("soreuseport: Resolve merge conflict for v4/v6
ordering fix") missed the opportunity to get rid of
hlist_nulls_add_tail_rcu() :

Both UDP sockets and TCP/DCCP listeners no longer use
__sk_nulls_add_node_rcu() for their hash insertion.

Since all other sockets have unique 4-tuple, the reuseport status
has no special meaning, so we can always use hlist_nulls_add_head_rcu()
for them and save few cycles/instructions.

[1]

==================================================================
BUG: KMSAN: use of uninitialized memory in inet_ehash_insert+0xd40/0x1050
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.13.0+ #3288
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 &lt;IRQ&gt;
 __dump_stack lib/dump_stack.c:16
 dump_stack+0x185/0x1d0 lib/dump_stack.c:52
 kmsan_report+0x13f/0x1c0 mm/kmsan/kmsan.c:1016
 __msan_warning_32+0x69/0xb0 mm/kmsan/kmsan_instr.c:766
 __sk_nulls_add_node_rcu ./include/net/sock.h:684
 inet_ehash_insert+0xd40/0x1050 net/ipv4/inet_hashtables.c:413
 reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:754
 inet_csk_reqsk_queue_hash_add+0x1cc/0x300 net/ipv4/inet_connection_sock.c:765
 tcp_conn_request+0x31e7/0x36f0 net/ipv4/tcp_input.c:6414
 tcp_v4_conn_request+0x16d/0x220 net/ipv4/tcp_ipv4.c:1314
 tcp_rcv_state_process+0x42a/0x7210 net/ipv4/tcp_input.c:5917
 tcp_v4_do_rcv+0xa6a/0xcd0 net/ipv4/tcp_ipv4.c:1483
 tcp_v4_rcv+0x3de0/0x4ab0 net/ipv4/tcp_ipv4.c:1763
 ip_local_deliver_finish+0x6bb/0xcb0 net/ipv4/ip_input.c:216
 NF_HOOK ./include/linux/netfilter.h:248
 ip_local_deliver+0x3fa/0x480 net/ipv4/ip_input.c:257
 dst_input ./include/net/dst.h:477
 ip_rcv_finish+0x6fb/0x1540 net/ipv4/ip_input.c:397
 NF_HOOK ./include/linux/netfilter.h:248
 ip_rcv+0x10f6/0x15c0 net/ipv4/ip_input.c:488
 __netif_receive_skb_core+0x36f6/0x3f60 net/core/dev.c:4298
 __netif_receive_skb net/core/dev.c:4336
 netif_receive_skb_internal+0x63c/0x19c0 net/core/dev.c:4497
 napi_skb_finish net/core/dev.c:4858
 napi_gro_receive+0x629/0xa50 net/core/dev.c:4889
 e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4018
 e1000_clean_rx_irq+0x1492/0x1d30
drivers/net/ethernet/intel/e1000/e1000_main.c:4474
 e1000_clean+0x43aa/0x5970 drivers/net/ethernet/intel/e1000/e1000_main.c:3819
 napi_poll net/core/dev.c:5500
 net_rx_action+0x73c/0x1820 net/core/dev.c:5566
 __do_softirq+0x4b4/0x8dd kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364
 irq_exit+0x203/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 ./arch/x86/include/asm/apic.h:638
 do_IRQ+0x15e/0x1a0 arch/x86/kernel/irq.c:263
 common_interrupt+0x86/0x86

Fixes: d894ba18d4e4 ("soreuseport: fix ordering for mixed v4/v6 sockets")
Fixes: d296ba60d8e2 ("soreuseport: Resolve merge conflict for v4/v6 ordering fix")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Alexander Potapenko &lt;glider@google.com&gt;
Acked-by: Craig Gallek &lt;kraig@google.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>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>tcp/dccp: fix other lockdep splats accessing ireq_opt</title>
<updated>2017-11-18T10:22:22+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2017-10-24T15:20:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2af59c6557a5f5e18b5552fe8526033b032978d5'/>
<id>2af59c6557a5f5e18b5552fe8526033b032978d5</id>
<content type='text'>
[ Upstream commit 06f877d613be3621604c2520ec0351d9fbdca15f ]

In my first attempt to fix the lockdep splat, I forgot we could
enter inet_csk_route_req() with a freshly allocated request socket,
for which refcount has not yet been elevated, due to complex
SLAB_TYPESAFE_BY_RCU rules.

We either are in rcu_read_lock() section _or_ we own a refcount on the
request.

Correct RCU verb to use here is rcu_dereference_check(), although it is
not possible to prove we actually own a reference on a shared
refcount :/

In v2, I added ireq_opt_deref() helper and use in three places, to fix other
possible splats.

[   49.844590]  lockdep_rcu_suspicious+0xea/0xf3
[   49.846487]  inet_csk_route_req+0x53/0x14d
[   49.848334]  tcp_v4_route_req+0xe/0x10
[   49.850174]  tcp_conn_request+0x31c/0x6a0
[   49.851992]  ? __lock_acquire+0x614/0x822
[   49.854015]  tcp_v4_conn_request+0x5a/0x79
[   49.855957]  ? tcp_v4_conn_request+0x5a/0x79
[   49.858052]  tcp_rcv_state_process+0x98/0xdcc
[   49.859990]  ? sk_filter_trim_cap+0x2f6/0x307
[   49.862085]  tcp_v4_do_rcv+0xfc/0x145
[   49.864055]  ? tcp_v4_do_rcv+0xfc/0x145
[   49.866173]  tcp_v4_rcv+0x5ab/0xaf9
[   49.868029]  ip_local_deliver_finish+0x1af/0x2e7
[   49.870064]  ip_local_deliver+0x1b2/0x1c5
[   49.871775]  ? inet_del_offload+0x45/0x45
[   49.873916]  ip_rcv_finish+0x3f7/0x471
[   49.875476]  ip_rcv+0x3f1/0x42f
[   49.876991]  ? ip_local_deliver_finish+0x2e7/0x2e7
[   49.878791]  __netif_receive_skb_core+0x6d3/0x950
[   49.880701]  ? process_backlog+0x7e/0x216
[   49.882589]  __netif_receive_skb+0x1d/0x5e
[   49.884122]  process_backlog+0x10c/0x216
[   49.885812]  net_rx_action+0x147/0x3df

Fixes: a6ca7abe53633 ("tcp/dccp: fix lockdep splat in inet_csk_route_req()")
Fixes: c92e8c02fe66 ("tcp/dccp: fix ireq-&gt;opt races")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: kernel test robot &lt;fengguang.wu@intel.com&gt;
Reported-by: Maciej Żenczykowski &lt;maze@google.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 06f877d613be3621604c2520ec0351d9fbdca15f ]

In my first attempt to fix the lockdep splat, I forgot we could
enter inet_csk_route_req() with a freshly allocated request socket,
for which refcount has not yet been elevated, due to complex
SLAB_TYPESAFE_BY_RCU rules.

We either are in rcu_read_lock() section _or_ we own a refcount on the
request.

Correct RCU verb to use here is rcu_dereference_check(), although it is
not possible to prove we actually own a reference on a shared
refcount :/

In v2, I added ireq_opt_deref() helper and use in three places, to fix other
possible splats.

[   49.844590]  lockdep_rcu_suspicious+0xea/0xf3
[   49.846487]  inet_csk_route_req+0x53/0x14d
[   49.848334]  tcp_v4_route_req+0xe/0x10
[   49.850174]  tcp_conn_request+0x31c/0x6a0
[   49.851992]  ? __lock_acquire+0x614/0x822
[   49.854015]  tcp_v4_conn_request+0x5a/0x79
[   49.855957]  ? tcp_v4_conn_request+0x5a/0x79
[   49.858052]  tcp_rcv_state_process+0x98/0xdcc
[   49.859990]  ? sk_filter_trim_cap+0x2f6/0x307
[   49.862085]  tcp_v4_do_rcv+0xfc/0x145
[   49.864055]  ? tcp_v4_do_rcv+0xfc/0x145
[   49.866173]  tcp_v4_rcv+0x5ab/0xaf9
[   49.868029]  ip_local_deliver_finish+0x1af/0x2e7
[   49.870064]  ip_local_deliver+0x1b2/0x1c5
[   49.871775]  ? inet_del_offload+0x45/0x45
[   49.873916]  ip_rcv_finish+0x3f7/0x471
[   49.875476]  ip_rcv+0x3f1/0x42f
[   49.876991]  ? ip_local_deliver_finish+0x2e7/0x2e7
[   49.878791]  __netif_receive_skb_core+0x6d3/0x950
[   49.880701]  ? process_backlog+0x7e/0x216
[   49.882589]  __netif_receive_skb+0x1d/0x5e
[   49.884122]  process_backlog+0x10c/0x216
[   49.885812]  net_rx_action+0x147/0x3df

Fixes: a6ca7abe53633 ("tcp/dccp: fix lockdep splat in inet_csk_route_req()")
Fixes: c92e8c02fe66 ("tcp/dccp: fix ireq-&gt;opt races")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: kernel test robot &lt;fengguang.wu@intel.com&gt;
Reported-by: Maciej Żenczykowski &lt;maze@google.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>tcp/dccp: fix ireq-&gt;opt races</title>
<updated>2017-11-18T10:22:22+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2017-10-20T16:04:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2ffd261337246d9a2992ca5083882790869f8986'/>
<id>2ffd261337246d9a2992ca5083882790869f8986</id>
<content type='text'>
[ Upstream commit c92e8c02fe664155ac4234516e32544bec0f113d ]

syzkaller found another bug in DCCP/TCP stacks [1]

For the reasons explained in commit ce1050089c96 ("tcp/dccp: fix
ireq-&gt;pktopts race"), we need to make sure we do not access
ireq-&gt;opt unless we own the request sock.

Note the opt field is renamed to ireq_opt to ease grep games.

[1]
BUG: KASAN: use-after-free in ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474
Read of size 1 at addr ffff8801c951039c by task syz-executor5/3295

CPU: 1 PID: 3295 Comm: syz-executor5 Not tainted 4.14.0-rc4+ #80
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427
 ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474
 tcp_transmit_skb+0x1ab7/0x3840 net/ipv4/tcp_output.c:1135
 tcp_send_ack.part.37+0x3bb/0x650 net/ipv4/tcp_output.c:3587
 tcp_send_ack+0x49/0x60 net/ipv4/tcp_output.c:3557
 __tcp_ack_snd_check+0x2c6/0x4b0 net/ipv4/tcp_input.c:5072
 tcp_ack_snd_check net/ipv4/tcp_input.c:5085 [inline]
 tcp_rcv_state_process+0x2eff/0x4850 net/ipv4/tcp_input.c:6071
 tcp_child_process+0x342/0x990 net/ipv4/tcp_minisocks.c:816
 tcp_v4_rcv+0x1827/0x2f80 net/ipv4/tcp_ipv4.c:1682
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:464 [inline]
 ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587
 netif_receive_skb+0xae/0x390 net/core/dev.c:4611
 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372
 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766
 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792
 call_write_iter include/linux/fs.h:1770 [inline]
 new_sync_write fs/read_write.c:468 [inline]
 __vfs_write+0x68a/0x970 fs/read_write.c:481
 vfs_write+0x18f/0x510 fs/read_write.c:543
 SYSC_write fs/read_write.c:588 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:580
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x40c341
RSP: 002b:00007f469523ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 000000000040c341
RDX: 0000000000000037 RSI: 0000000020004000 RDI: 0000000000000015
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000f4240 R11: 0000000000000293 R12: 00000000004b7fd1
R13: 00000000ffffffff R14: 0000000020000000 R15: 0000000000025000

Allocated by task 3295:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 __do_kmalloc mm/slab.c:3725 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3734
 kmalloc include/linux/slab.h:498 [inline]
 tcp_v4_save_options include/net/tcp.h:1962 [inline]
 tcp_v4_init_req+0x2d3/0x3e0 net/ipv4/tcp_ipv4.c:1271
 tcp_conn_request+0xf6d/0x3410 net/ipv4/tcp_input.c:6283
 tcp_v4_conn_request+0x157/0x210 net/ipv4/tcp_ipv4.c:1313
 tcp_rcv_state_process+0x8ea/0x4850 net/ipv4/tcp_input.c:5857
 tcp_v4_do_rcv+0x55c/0x7d0 net/ipv4/tcp_ipv4.c:1482
 tcp_v4_rcv+0x2d10/0x2f80 net/ipv4/tcp_ipv4.c:1711
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:464 [inline]
 ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587
 netif_receive_skb+0xae/0x390 net/core/dev.c:4611
 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372
 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766
 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792
 call_write_iter include/linux/fs.h:1770 [inline]
 new_sync_write fs/read_write.c:468 [inline]
 __vfs_write+0x68a/0x970 fs/read_write.c:481
 vfs_write+0x18f/0x510 fs/read_write.c:543
 SYSC_write fs/read_write.c:588 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:580
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 3306:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xca/0x250 mm/slab.c:3820
 inet_sock_destruct+0x59d/0x950 net/ipv4/af_inet.c:157
 __sk_destruct+0xfd/0x910 net/core/sock.c:1560
 sk_destruct+0x47/0x80 net/core/sock.c:1595
 __sk_free+0x57/0x230 net/core/sock.c:1603
 sk_free+0x2a/0x40 net/core/sock.c:1614
 sock_put include/net/sock.h:1652 [inline]
 inet_csk_complete_hashdance+0xd5/0xf0 net/ipv4/inet_connection_sock.c:959
 tcp_check_req+0xf4d/0x1620 net/ipv4/tcp_minisocks.c:765
 tcp_v4_rcv+0x17f6/0x2f80 net/ipv4/tcp_ipv4.c:1675
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:464 [inline]
 ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587
 netif_receive_skb+0xae/0x390 net/core/dev.c:4611
 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372
 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766
 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792
 call_write_iter include/linux/fs.h:1770 [inline]
 new_sync_write fs/read_write.c:468 [inline]
 __vfs_write+0x68a/0x970 fs/read_write.c:481
 vfs_write+0x18f/0x510 fs/read_write.c:543
 SYSC_write fs/read_write.c:588 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:580
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets")
Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet &lt;edumazet@google.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 c92e8c02fe664155ac4234516e32544bec0f113d ]

syzkaller found another bug in DCCP/TCP stacks [1]

For the reasons explained in commit ce1050089c96 ("tcp/dccp: fix
ireq-&gt;pktopts race"), we need to make sure we do not access
ireq-&gt;opt unless we own the request sock.

Note the opt field is renamed to ireq_opt to ease grep games.

[1]
BUG: KASAN: use-after-free in ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474
Read of size 1 at addr ffff8801c951039c by task syz-executor5/3295

CPU: 1 PID: 3295 Comm: syz-executor5 Not tainted 4.14.0-rc4+ #80
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427
 ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474
 tcp_transmit_skb+0x1ab7/0x3840 net/ipv4/tcp_output.c:1135
 tcp_send_ack.part.37+0x3bb/0x650 net/ipv4/tcp_output.c:3587
 tcp_send_ack+0x49/0x60 net/ipv4/tcp_output.c:3557
 __tcp_ack_snd_check+0x2c6/0x4b0 net/ipv4/tcp_input.c:5072
 tcp_ack_snd_check net/ipv4/tcp_input.c:5085 [inline]
 tcp_rcv_state_process+0x2eff/0x4850 net/ipv4/tcp_input.c:6071
 tcp_child_process+0x342/0x990 net/ipv4/tcp_minisocks.c:816
 tcp_v4_rcv+0x1827/0x2f80 net/ipv4/tcp_ipv4.c:1682
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:464 [inline]
 ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587
 netif_receive_skb+0xae/0x390 net/core/dev.c:4611
 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372
 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766
 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792
 call_write_iter include/linux/fs.h:1770 [inline]
 new_sync_write fs/read_write.c:468 [inline]
 __vfs_write+0x68a/0x970 fs/read_write.c:481
 vfs_write+0x18f/0x510 fs/read_write.c:543
 SYSC_write fs/read_write.c:588 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:580
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x40c341
RSP: 002b:00007f469523ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 000000000040c341
RDX: 0000000000000037 RSI: 0000000020004000 RDI: 0000000000000015
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000f4240 R11: 0000000000000293 R12: 00000000004b7fd1
R13: 00000000ffffffff R14: 0000000020000000 R15: 0000000000025000

Allocated by task 3295:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 __do_kmalloc mm/slab.c:3725 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3734
 kmalloc include/linux/slab.h:498 [inline]
 tcp_v4_save_options include/net/tcp.h:1962 [inline]
 tcp_v4_init_req+0x2d3/0x3e0 net/ipv4/tcp_ipv4.c:1271
 tcp_conn_request+0xf6d/0x3410 net/ipv4/tcp_input.c:6283
 tcp_v4_conn_request+0x157/0x210 net/ipv4/tcp_ipv4.c:1313
 tcp_rcv_state_process+0x8ea/0x4850 net/ipv4/tcp_input.c:5857
 tcp_v4_do_rcv+0x55c/0x7d0 net/ipv4/tcp_ipv4.c:1482
 tcp_v4_rcv+0x2d10/0x2f80 net/ipv4/tcp_ipv4.c:1711
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:464 [inline]
 ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587
 netif_receive_skb+0xae/0x390 net/core/dev.c:4611
 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372
 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766
 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792
 call_write_iter include/linux/fs.h:1770 [inline]
 new_sync_write fs/read_write.c:468 [inline]
 __vfs_write+0x68a/0x970 fs/read_write.c:481
 vfs_write+0x18f/0x510 fs/read_write.c:543
 SYSC_write fs/read_write.c:588 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:580
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 3306:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xca/0x250 mm/slab.c:3820
 inet_sock_destruct+0x59d/0x950 net/ipv4/af_inet.c:157
 __sk_destruct+0xfd/0x910 net/core/sock.c:1560
 sk_destruct+0x47/0x80 net/core/sock.c:1595
 __sk_free+0x57/0x230 net/core/sock.c:1603
 sk_free+0x2a/0x40 net/core/sock.c:1614
 sock_put include/net/sock.h:1652 [inline]
 inet_csk_complete_hashdance+0xd5/0xf0 net/ipv4/inet_connection_sock.c:959
 tcp_check_req+0xf4d/0x1620 net/ipv4/tcp_minisocks.c:765
 tcp_v4_rcv+0x17f6/0x2f80 net/ipv4/tcp_ipv4.c:1675
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:464 [inline]
 ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:249 [inline]
 ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587
 netif_receive_skb+0xae/0x390 net/core/dev.c:4611
 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372
 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766
 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792
 call_write_iter include/linux/fs.h:1770 [inline]
 new_sync_write fs/read_write.c:468 [inline]
 __vfs_write+0x68a/0x970 fs/read_write.c:481
 vfs_write+0x18f/0x510 fs/read_write.c:543
 SYSC_write fs/read_write.c:588 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:580
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets")
Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet &lt;edumazet@google.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>tcp: fix tcp_mtu_probe() vs highest_sack</title>
<updated>2017-11-18T10:22:21+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2017-10-31T06:08:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e12c42c55287f39bfbaa2ab7e9cf04c88879768f'/>
<id>e12c42c55287f39bfbaa2ab7e9cf04c88879768f</id>
<content type='text'>
[ Upstream commit 2b7cda9c35d3b940eb9ce74b30bbd5eb30db493d ]

Based on SNMP values provided by Roman, Yuchung made the observation
that some crashes in tcp_sacktag_walk() might be caused by MTU probing.

Looking at tcp_mtu_probe(), I found that when a new skb was placed
in front of the write queue, we were not updating tcp highest sack.

If one skb is freed because all its content was copied to the new skb
(for MTU probing), then tp-&gt;highest_sack could point to a now freed skb.

Bad things would then happen, including infinite loops.

This patch renames tcp_highest_sack_combine() and uses it
from tcp_mtu_probe() to fix the bug.

Note that I also removed one test against tp-&gt;sacked_out,
since we want to replace tp-&gt;highest_sack regardless of whatever
condition, since keeping a stale pointer to freed skb is a recipe
for disaster.

Fixes: a47e5a988a57 ("[TCP]: Convert highest_sack to sk_buff to allow direct access")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Alexei Starovoitov &lt;alexei.starovoitov@gmail.com&gt;
Reported-by: Roman Gushchin &lt;guro@fb.com&gt;
Reported-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Acked-by: Yuchung Cheng &lt;ycheng@google.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 2b7cda9c35d3b940eb9ce74b30bbd5eb30db493d ]

Based on SNMP values provided by Roman, Yuchung made the observation
that some crashes in tcp_sacktag_walk() might be caused by MTU probing.

Looking at tcp_mtu_probe(), I found that when a new skb was placed
in front of the write queue, we were not updating tcp highest sack.

If one skb is freed because all its content was copied to the new skb
(for MTU probing), then tp-&gt;highest_sack could point to a now freed skb.

Bad things would then happen, including infinite loops.

This patch renames tcp_highest_sack_combine() and uses it
from tcp_mtu_probe() to fix the bug.

Note that I also removed one test against tp-&gt;sacked_out,
since we want to replace tp-&gt;highest_sack regardless of whatever
condition, since keeping a stale pointer to freed skb is a recipe
for disaster.

Fixes: a47e5a988a57 ("[TCP]: Convert highest_sack to sk_buff to allow direct access")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Alexei Starovoitov &lt;alexei.starovoitov@gmail.com&gt;
Reported-by: Roman Gushchin &lt;guro@fb.com&gt;
Reported-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Acked-by: Yuchung Cheng &lt;ycheng@google.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>netlink: fix nla_put_{u8,u16,u32} for KASAN</title>
<updated>2017-10-12T09:51:25+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2017-09-22T21:29:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9a19bc44c63696db85309148609a963970ad9cc9'/>
<id>9a19bc44c63696db85309148609a963970ad9cc9</id>
<content type='text'>
commit b4391db42308c9940944b5d7be5ca4b78fb88dd0 upstream.

When CONFIG_KASAN is enabled, the "--param asan-stack=1" causes rather large
stack frames in some functions. This goes unnoticed normally because
CONFIG_FRAME_WARN is disabled with CONFIG_KASAN by default as of commit
3f181b4d8652 ("lib/Kconfig.debug: disable -Wframe-larger-than warnings with
KASAN=y").

The kernelci.org build bot however has the warning enabled and that led
me to investigate it a little further, as every build produces these warnings:

net/wireless/nl80211.c:4389:1: warning: the frame size of 2240 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/wireless/nl80211.c:1895:1: warning: the frame size of 3776 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/wireless/nl80211.c:1410:1: warning: the frame size of 2208 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/bridge/br_netlink.c:1282:1: warning: the frame size of 2544 bytes is larger than 2048 bytes [-Wframe-larger-than=]

Most of this problem is now solved in gcc-8, which can consolidate
the stack slots for the inline function arguments. On older compilers
we can add a workaround by declaring a local variable in each function
to pass the inline function argument.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
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>
commit b4391db42308c9940944b5d7be5ca4b78fb88dd0 upstream.

When CONFIG_KASAN is enabled, the "--param asan-stack=1" causes rather large
stack frames in some functions. This goes unnoticed normally because
CONFIG_FRAME_WARN is disabled with CONFIG_KASAN by default as of commit
3f181b4d8652 ("lib/Kconfig.debug: disable -Wframe-larger-than warnings with
KASAN=y").

The kernelci.org build bot however has the warning enabled and that led
me to investigate it a little further, as every build produces these warnings:

net/wireless/nl80211.c:4389:1: warning: the frame size of 2240 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/wireless/nl80211.c:1895:1: warning: the frame size of 3776 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/wireless/nl80211.c:1410:1: warning: the frame size of 2208 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/bridge/br_netlink.c:1282:1: warning: the frame size of 2544 bytes is larger than 2048 bytes [-Wframe-larger-than=]

Most of this problem is now solved in gcc-8, which can consolidate
the stack slots for the inline function arguments. On older compilers
we can add a workaround by declaring a local variable in each function
to pass the inline function argument.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
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>sctp: potential read out of bounds in sctp_ulpevent_type_enabled()</title>
<updated>2017-10-12T09:51:20+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2017-09-13T23:00:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b70bb9bb7277aa396eafab6a313ee829c7957587'/>
<id>b70bb9bb7277aa396eafab6a313ee829c7957587</id>
<content type='text'>
[ Upstream commit fa5f7b51fc3080c2b195fa87c7eca7c05e56f673 ]

This code causes a static checker warning because Smatch doesn't trust
anything that comes from skb-&gt;data.  I've reviewed this code and I do
think skb-&gt;data can be controlled by the user here.

The sctp_event_subscribe struct has 13 __u8 fields and we want to see
if ours is non-zero.  sn_type can be any value in the 0-USHRT_MAX range.
We're subtracting SCTP_SN_TYPE_BASE which is 1 &lt;&lt; 15 so we could read
either before the start of the struct or after the end.

This is a very old bug and it's surprising that it would go undetected
for so long but my theory is that it just doesn't have a big impact so
it would be hard to notice.

Signed-off-by: Dan Carpenter &lt;dan.carpenter@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 fa5f7b51fc3080c2b195fa87c7eca7c05e56f673 ]

This code causes a static checker warning because Smatch doesn't trust
anything that comes from skb-&gt;data.  I've reviewed this code and I do
think skb-&gt;data can be controlled by the user here.

The sctp_event_subscribe struct has 13 __u8 fields and we want to see
if ours is non-zero.  sn_type can be any value in the 0-USHRT_MAX range.
We're subtracting SCTP_SN_TYPE_BASE which is 1 &lt;&lt; 15 so we could read
either before the start of the struct or after the end.

This is a very old bug and it's surprising that it would go undetected
for so long but my theory is that it just doesn't have a big impact so
it would be hard to notice.

Signed-off-by: Dan Carpenter &lt;dan.carpenter@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>
</feed>
