<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/ipv4, branch v5.4.30</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>vti[6]: fix packet tx through bpf_redirect() in XinY cases</title>
<updated>2020-04-01T09:02:05+00:00</updated>
<author>
<name>Nicolas Dichtel</name>
<email>nicolas.dichtel@6wind.com</email>
</author>
<published>2020-02-04T16:00:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f8f90690df593e36ee43ec732379b9b2ae474b16'/>
<id>f8f90690df593e36ee43ec732379b9b2ae474b16</id>
<content type='text'>
commit f1ed10264ed6b66b9cd5e8461cffce69be482356 upstream.

I forgot the 4in6/6in4 cases in my previous patch. Let's fix them.

Fixes: 95224166a903 ("vti[6]: fix packet tx through bpf_redirect()")
Signed-off-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.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>
commit f1ed10264ed6b66b9cd5e8461cffce69be482356 upstream.

I forgot the 4in6/6in4 cases in my previous patch. Let's fix them.

Fixes: 95224166a903 ("vti[6]: fix packet tx through bpf_redirect()")
Signed-off-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>net: ip_gre: Accept IFLA_INFO_DATA-less configuration</title>
<updated>2020-04-01T09:01:46+00:00</updated>
<author>
<name>Petr Machata</name>
<email>petrm@mellanox.com</email>
</author>
<published>2020-03-16T17:53:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e4723e0a858e6ba960c42c5df835e851a49ba1f6'/>
<id>e4723e0a858e6ba960c42c5df835e851a49ba1f6</id>
<content type='text'>
[ Upstream commit 32ca98feab8c9076c89c0697c5a85e46fece809d ]

The fix referenced below causes a crash when an ERSPAN tunnel is created
without passing IFLA_INFO_DATA. Fix by validating passed-in data in the
same way as ipgre does.

Fixes: e1f8f78ffe98 ("net: ip_gre: Separate ERSPAN newlink / changelink callbacks")
Reported-by: syzbot+1b4ebf4dae4e510dd219@syzkaller.appspotmail.com
Signed-off-by: Petr Machata &lt;petrm@mellanox.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 32ca98feab8c9076c89c0697c5a85e46fece809d ]

The fix referenced below causes a crash when an ERSPAN tunnel is created
without passing IFLA_INFO_DATA. Fix by validating passed-in data in the
same way as ipgre does.

Fixes: e1f8f78ffe98 ("net: ip_gre: Separate ERSPAN newlink / changelink callbacks")
Reported-by: syzbot+1b4ebf4dae4e510dd219@syzkaller.appspotmail.com
Signed-off-by: Petr Machata &lt;petrm@mellanox.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>net: ip_gre: Separate ERSPAN newlink / changelink callbacks</title>
<updated>2020-04-01T09:01:46+00:00</updated>
<author>
<name>Petr Machata</name>
<email>petrm@mellanox.com</email>
</author>
<published>2020-03-13T11:39:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=85aa84d3c5877ee999546729892ae6c5dbaeac3c'/>
<id>85aa84d3c5877ee999546729892ae6c5dbaeac3c</id>
<content type='text'>
[ Upstream commit e1f8f78ffe9854308b9e12a73ebe4e909074fc33 ]

ERSPAN shares most of the code path with GRE and gretap code. While that
helps keep the code compact, it is also error prone. Currently a broken
userspace can turn a gretap tunnel into a de facto ERSPAN one by passing
IFLA_GRE_ERSPAN_VER. There has been a similar issue in ip6gretap in the
past.

To prevent these problems in future, split the newlink and changelink code
paths. Split the ERSPAN code out of ipgre_netlink_parms() into a new
function erspan_netlink_parms(). Extract a piece of common logic from
ipgre_newlink() and ipgre_changelink() into ipgre_newlink_encap_setup().
Add erspan_newlink() and erspan_changelink().

Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: Petr Machata &lt;petrm@mellanox.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 e1f8f78ffe9854308b9e12a73ebe4e909074fc33 ]

ERSPAN shares most of the code path with GRE and gretap code. While that
helps keep the code compact, it is also error prone. Currently a broken
userspace can turn a gretap tunnel into a de facto ERSPAN one by passing
IFLA_GRE_ERSPAN_VER. There has been a similar issue in ip6gretap in the
past.

To prevent these problems in future, split the newlink and changelink code
paths. Split the ERSPAN code out of ipgre_netlink_parms() into a new
function erspan_netlink_parms(). Extract a piece of common logic from
ipgre_newlink() and ipgre_changelink() into ipgre_newlink_encap_setup().
Add erspan_newlink() and erspan_changelink().

Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: Petr Machata &lt;petrm@mellanox.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: repair: fix TCP_QUEUE_SEQ implementation</title>
<updated>2020-04-01T09:01:39+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2020-03-19T02:21:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a6ce82deba5cbeea18c6b91f4237c7f9e911745b'/>
<id>a6ce82deba5cbeea18c6b91f4237c7f9e911745b</id>
<content type='text'>
[ Upstream commit 6cd6cbf593bfa3ae6fc3ed34ac21da4d35045425 ]

When application uses TCP_QUEUE_SEQ socket option to
change tp-&gt;rcv_next, we must also update tp-&gt;copied_seq.

Otherwise, stuff relying on tcp_inq() being precise can
eventually be confused.

For example, tcp_zerocopy_receive() might crash because
it does not expect tcp_recv_skb() to return NULL.

We could add tests in various places to fix the issue,
or simply make sure tcp_inq() wont return a random value,
and leave fast path as it is.

Note that this fixes ioctl(fd, SIOCINQ, &amp;val) at the same
time.

Fixes: ee9952831cfd ("tcp: Initial repair mode")
Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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 6cd6cbf593bfa3ae6fc3ed34ac21da4d35045425 ]

When application uses TCP_QUEUE_SEQ socket option to
change tp-&gt;rcv_next, we must also update tp-&gt;copied_seq.

Otherwise, stuff relying on tcp_inq() being precise can
eventually be confused.

For example, tcp_zerocopy_receive() might crash because
it does not expect tcp_recv_skb() to return NULL.

We could add tests in various places to fix the issue,
or simply make sure tcp_inq() wont return a random value,
and leave fast path as it is.

Note that this fixes ioctl(fd, SIOCINQ, &amp;val) at the same
time.

Fixes: ee9952831cfd ("tcp: Initial repair mode")
Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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: ensure skb-&gt;dev is NULL before leaving TCP stack</title>
<updated>2020-04-01T09:01:39+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2020-03-19T19:49:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=27cf5410a9e16ad8672aaa005657c5785565acd4'/>
<id>27cf5410a9e16ad8672aaa005657c5785565acd4</id>
<content type='text'>
[ Upstream commit b738a185beaab8728943acdb3e67371b8a88185e ]

skb-&gt;rbnode is sharing three skb fields : next, prev, dev

When a packet is sent, TCP keeps the original skb (master)
in a rtx queue, which was converted to rbtree a while back.

__tcp_transmit_skb() is responsible to clone the master skb,
and add the TCP header to the clone before sending it
to network layer.

skb_clone() already clears skb-&gt;next and skb-&gt;prev, but copies
the master oskb-&gt;dev into the clone.

We need to clear skb-&gt;dev, otherwise lower layers could interpret
the value as a pointer to a netdev.

This old bug surfaced recently when commit 28f8bfd1ac94
("netfilter: Support iif matches in POSTROUTING") was merged.

Before this netfilter commit, skb-&gt;dev value was ignored and
changed before reaching dev_queue_xmit()

Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue")
Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Martin Zaharinov &lt;micron10@gmail.com&gt;
Cc: Florian Westphal &lt;fw@strlen.de&gt;
Cc: Pablo Neira Ayuso &lt;pablo@netfilter.org&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 b738a185beaab8728943acdb3e67371b8a88185e ]

skb-&gt;rbnode is sharing three skb fields : next, prev, dev

When a packet is sent, TCP keeps the original skb (master)
in a rtx queue, which was converted to rbtree a while back.

__tcp_transmit_skb() is responsible to clone the master skb,
and add the TCP header to the clone before sending it
to network layer.

skb_clone() already clears skb-&gt;next and skb-&gt;prev, but copies
the master oskb-&gt;dev into the clone.

We need to clear skb-&gt;dev, otherwise lower layers could interpret
the value as a pointer to a netdev.

This old bug surfaced recently when commit 28f8bfd1ac94
("netfilter: Support iif matches in POSTROUTING") was merged.

Before this netfilter commit, skb-&gt;dev value was ignored and
changed before reaching dev_queue_xmit()

Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue")
Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Martin Zaharinov &lt;micron10@gmail.com&gt;
Cc: Florian Westphal &lt;fw@strlen.de&gt;
Cc: Pablo Neira Ayuso &lt;pablo@netfilter.org&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: also NULL skb-&gt;dev when copy was needed</title>
<updated>2020-04-01T09:01:39+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2020-03-20T15:52:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c94b94626876b4c3885827e4f44498166a782c60'/>
<id>c94b94626876b4c3885827e4f44498166a782c60</id>
<content type='text'>
[ Upstream commit 07f8e4d0fddbf2f87e4cefb551278abc38db8cdd ]

In rare cases retransmit logic will make a full skb copy, which will not
trigger the zeroing added in recent change
b738a185beaa ("tcp: ensure skb-&gt;dev is NULL before leaving TCP stack").

Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue")
Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING")
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
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 07f8e4d0fddbf2f87e4cefb551278abc38db8cdd ]

In rare cases retransmit logic will make a full skb copy, which will not
trigger the zeroing added in recent change
b738a185beaa ("tcp: ensure skb-&gt;dev is NULL before leaving TCP stack").

Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue")
Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING")
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
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>ipv4: fix a RCU-list lock in inet_dump_fib()</title>
<updated>2020-04-01T09:01:31+00:00</updated>
<author>
<name>Qian Cai</name>
<email>cai@lca.pw</email>
</author>
<published>2020-03-20T02:54:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=51db2db8fe68d33de177180f5c32e70c51574200'/>
<id>51db2db8fe68d33de177180f5c32e70c51574200</id>
<content type='text'>
[ Upstream commit dddeb30bfc43926620f954266fd12c65a7206f07 ]

There is a place,

inet_dump_fib()
  fib_table_dump
    fn_trie_dump_leaf()
      hlist_for_each_entry_rcu()

without rcu_read_lock() will trigger a warning,

 WARNING: suspicious RCU usage
 -----------------------------
 net/ipv4/fib_trie.c:2216 RCU-list traversed in non-reader section!!

 other info that might help us debug this:

 rcu_scheduler_active = 2, debug_locks = 1
 1 lock held by ip/1923:
  #0: ffffffff8ce76e40 (rtnl_mutex){+.+.}, at: netlink_dump+0xd6/0x840

 Call Trace:
  dump_stack+0xa1/0xea
  lockdep_rcu_suspicious+0x103/0x10d
  fn_trie_dump_leaf+0x581/0x590
  fib_table_dump+0x15f/0x220
  inet_dump_fib+0x4ad/0x5d0
  netlink_dump+0x350/0x840
  __netlink_dump_start+0x315/0x3e0
  rtnetlink_rcv_msg+0x4d1/0x720
  netlink_rcv_skb+0xf0/0x220
  rtnetlink_rcv+0x15/0x20
  netlink_unicast+0x306/0x460
  netlink_sendmsg+0x44b/0x770
  __sys_sendto+0x259/0x270
  __x64_sys_sendto+0x80/0xa0
  do_syscall_64+0x69/0xf4
  entry_SYSCALL_64_after_hwframe+0x49/0xb3

Fixes: 18a8021a7be3 ("net/ipv4: Plumb support for filtering route dumps")
Signed-off-by: Qian Cai &lt;cai@lca.pw&gt;
Reviewed-by: David Ahern &lt;dsahern@gmail.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 dddeb30bfc43926620f954266fd12c65a7206f07 ]

There is a place,

inet_dump_fib()
  fib_table_dump
    fn_trie_dump_leaf()
      hlist_for_each_entry_rcu()

without rcu_read_lock() will trigger a warning,

 WARNING: suspicious RCU usage
 -----------------------------
 net/ipv4/fib_trie.c:2216 RCU-list traversed in non-reader section!!

 other info that might help us debug this:

 rcu_scheduler_active = 2, debug_locks = 1
 1 lock held by ip/1923:
  #0: ffffffff8ce76e40 (rtnl_mutex){+.+.}, at: netlink_dump+0xd6/0x840

 Call Trace:
  dump_stack+0xa1/0xea
  lockdep_rcu_suspicious+0x103/0x10d
  fn_trie_dump_leaf+0x581/0x590
  fib_table_dump+0x15f/0x220
  inet_dump_fib+0x4ad/0x5d0
  netlink_dump+0x350/0x840
  __netlink_dump_start+0x315/0x3e0
  rtnetlink_rcv_msg+0x4d1/0x720
  netlink_rcv_skb+0xf0/0x220
  rtnetlink_rcv+0x15/0x20
  netlink_unicast+0x306/0x460
  netlink_sendmsg+0x44b/0x770
  __sys_sendto+0x259/0x270
  __x64_sys_sendto+0x80/0xa0
  do_syscall_64+0x69/0xf4
  entry_SYSCALL_64_after_hwframe+0x49/0xb3

Fixes: 18a8021a7be3 ("net/ipv4: Plumb support for filtering route dumps")
Signed-off-by: Qian Cai &lt;cai@lca.pw&gt;
Reviewed-by: David Ahern &lt;dsahern@gmail.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: ensure rcu_read_lock() in cipso_v4_error()</title>
<updated>2020-03-21T07:11:59+00:00</updated>
<author>
<name>Matteo Croce</name>
<email>mcroce@redhat.com</email>
</author>
<published>2020-02-21T11:28:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=20ba40d262b0d88e6cf3e2eaf756ad70809018c6'/>
<id>20ba40d262b0d88e6cf3e2eaf756ad70809018c6</id>
<content type='text'>
commit 3e72dfdf8227b052393f71d820ec7599909dddc2 upstream.

Similarly to commit c543cb4a5f07 ("ipv4: ensure rcu_read_lock() in
ipv4_link_failure()"), __ip_options_compile() must be called under rcu
protection.

Fixes: 3da1ed7ac398 ("net: avoid use IPCB in cipso_v4_error")
Suggested-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Signed-off-by: Matteo Croce &lt;mcroce@redhat.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.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>
commit 3e72dfdf8227b052393f71d820ec7599909dddc2 upstream.

Similarly to commit c543cb4a5f07 ("ipv4: ensure rcu_read_lock() in
ipv4_link_failure()"), __ip_options_compile() must be called under rcu
protection.

Fixes: 3da1ed7ac398 ("net: avoid use IPCB in cipso_v4_error")
Suggested-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Signed-off-by: Matteo Croce &lt;mcroce@redhat.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.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>net: memcg: fix lockdep splat in inet_csk_accept()</title>
<updated>2020-03-18T06:17:43+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2020-03-11T18:44:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c0a7416a5403df10136a74d9b52a84b0f2471272'/>
<id>c0a7416a5403df10136a74d9b52a84b0f2471272</id>
<content type='text'>
commit 06669ea346e476a5339033d77ef175566a40efbb upstream.

Locking newsk while still holding the listener lock triggered
a lockdep splat [1]

We can simply move the memcg code after we release the listener lock,
as this can also help if multiple threads are sharing a common listener.

Also fix a typo while reading socket sk_rmem_alloc.

[1]
WARNING: possible recursive locking detected
5.6.0-rc3-syzkaller #0 Not tainted
--------------------------------------------
syz-executor598/9524 is trying to acquire lock:
ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline]
ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492

but task is already holding lock:
ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline]
ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(sk_lock-AF_INET6);
  lock(sk_lock-AF_INET6);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

1 lock held by syz-executor598/9524:
 #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline]
 #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445

stack backtrace:
CPU: 0 PID: 9524 Comm: syz-executor598 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_deadlock_bug kernel/locking/lockdep.c:2370 [inline]
 check_deadlock kernel/locking/lockdep.c:2411 [inline]
 validate_chain kernel/locking/lockdep.c:2954 [inline]
 __lock_acquire.cold+0x114/0x288 kernel/locking/lockdep.c:3954
 lock_acquire+0x197/0x420 kernel/locking/lockdep.c:4484
 lock_sock_nested+0xc5/0x110 net/core/sock.c:2947
 lock_sock include/net/sock.h:1541 [inline]
 inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492
 inet_accept+0xe9/0x7c0 net/ipv4/af_inet.c:734
 __sys_accept4_file+0x3ac/0x5b0 net/socket.c:1758
 __sys_accept4+0x53/0x90 net/socket.c:1809
 __do_sys_accept4 net/socket.c:1821 [inline]
 __se_sys_accept4 net/socket.c:1818 [inline]
 __x64_sys_accept4+0x93/0xf0 net/socket.c:1818
 do_syscall_64+0xf6/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4445c9
Code: e8 0c 0d 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc35b37608 EFLAGS: 00000246 ORIG_RAX: 0000000000000120
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004445c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000306777 R09: 0000000000306777
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000004053d0 R14: 0000000000000000 R15: 0000000000000000

Fixes: d752a4986532 ("net: memcg: late association of sock to memcg")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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>
commit 06669ea346e476a5339033d77ef175566a40efbb upstream.

Locking newsk while still holding the listener lock triggered
a lockdep splat [1]

We can simply move the memcg code after we release the listener lock,
as this can also help if multiple threads are sharing a common listener.

Also fix a typo while reading socket sk_rmem_alloc.

[1]
WARNING: possible recursive locking detected
5.6.0-rc3-syzkaller #0 Not tainted
--------------------------------------------
syz-executor598/9524 is trying to acquire lock:
ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline]
ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492

but task is already holding lock:
ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline]
ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(sk_lock-AF_INET6);
  lock(sk_lock-AF_INET6);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

1 lock held by syz-executor598/9524:
 #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline]
 #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445

stack backtrace:
CPU: 0 PID: 9524 Comm: syz-executor598 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_deadlock_bug kernel/locking/lockdep.c:2370 [inline]
 check_deadlock kernel/locking/lockdep.c:2411 [inline]
 validate_chain kernel/locking/lockdep.c:2954 [inline]
 __lock_acquire.cold+0x114/0x288 kernel/locking/lockdep.c:3954
 lock_acquire+0x197/0x420 kernel/locking/lockdep.c:4484
 lock_sock_nested+0xc5/0x110 net/core/sock.c:2947
 lock_sock include/net/sock.h:1541 [inline]
 inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492
 inet_accept+0xe9/0x7c0 net/ipv4/af_inet.c:734
 __sys_accept4_file+0x3ac/0x5b0 net/socket.c:1758
 __sys_accept4+0x53/0x90 net/socket.c:1809
 __do_sys_accept4 net/socket.c:1821 [inline]
 __se_sys_accept4 net/socket.c:1818 [inline]
 __x64_sys_accept4+0x93/0xf0 net/socket.c:1818
 do_syscall_64+0xf6/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4445c9
Code: e8 0c 0d 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc35b37608 EFLAGS: 00000246 ORIG_RAX: 0000000000000120
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004445c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000306777 R09: 0000000000306777
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000004053d0 R14: 0000000000000000 R15: 0000000000000000

Fixes: d752a4986532 ("net: memcg: late association of sock to memcg")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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>net: memcg: late association of sock to memcg</title>
<updated>2020-03-18T06:17:43+00:00</updated>
<author>
<name>Shakeel Butt</name>
<email>shakeelb@google.com</email>
</author>
<published>2020-03-10T05:16:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4a14448182003e947ccab02fea305777bb52ef23'/>
<id>4a14448182003e947ccab02fea305777bb52ef23</id>
<content type='text'>
[ Upstream commit d752a4986532cb6305dfd5290a614cde8072769d ]

If a TCP socket is allocated in IRQ context or cloned from unassociated
(i.e. not associated to a memcg) in IRQ context then it will remain
unassociated for its whole life. Almost half of the TCPs created on the
system are created in IRQ context, so, memory used by such sockets will
not be accounted by the memcg.

This issue is more widespread in cgroup v1 where network memory
accounting is opt-in but it can happen in cgroup v2 if the source socket
for the cloning was created in root memcg.

To fix the issue, just do the association of the sockets at the accept()
time in the process context and then force charge the memory buffer
already used and reserved by the socket.

Signed-off-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Reviewed-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 d752a4986532cb6305dfd5290a614cde8072769d ]

If a TCP socket is allocated in IRQ context or cloned from unassociated
(i.e. not associated to a memcg) in IRQ context then it will remain
unassociated for its whole life. Almost half of the TCPs created on the
system are created in IRQ context, so, memory used by such sockets will
not be accounted by the memcg.

This issue is more widespread in cgroup v1 where network memory
accounting is opt-in but it can happen in cgroup v2 if the source socket
for the cloning was created in root memcg.

To fix the issue, just do the association of the sockets at the accept()
time in the process context and then force charge the memory buffer
already used and reserved by the socket.

Signed-off-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Reviewed-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>
</feed>
