Upstream commit 008ba2a13f2d ("packet: hold bind lock when rebinding to fanout hook"). Already fixed in chromeos-4.4 with merge of v4.4.96. Needed in M-63 and older kernels.

Applied to chromeos-4.4/M-63 with b/69149598.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/kernel/+/62dfc4fa19f20850cace0ab85da2529c0d0c980a

commit 62dfc4fa19f20850cace0ab85da2529c0d0c980a
Author: Willem de Bruijn <willemb@google.com>
Date: Tue Nov 21 23:58:37 2017

UPSTREAM: packet: hold bind lock when rebinding to fanout hook

[ Upstream commit 008ba2a13f2d04c947adc536d19debb8fe66f110 ]

Packet socket bind operations must hold the po->bind_lock. This keeps
po->running consistent with whether the socket is actually on a ptype
list to receive packets.

fanout_add unbinds a socket and its packet_rcv/tpacket_rcv call, then
binds the fanout object to receive through packet_rcv_fanout.

Make it hold the po->bind_lock when testing po->running and rebinding.
Else, it can race with other rebind operations, such as that in
packet_set_ring from packet_rcv to tpacket_rcv. Concurrent updates
can result in a socket being added to a fanout group twice, causing
use-after-free KASAN bug reports, among others.

Reported independently by both trinity and syzkaller.
Verified that the syzkaller reproducer passes after this patch.

Fixes: dc99f600698d ("packet: Add fanout support.")
Reported-by: nixioaming <nixiaoming@huawei.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 5be6824b9704f926c26c844b373aacdc7e827ab6)
Signed-off-by: Robert Kolchmeyer <rkolchmeyer@google.com>

BUG=b:69149598, chromium:783729 
CQ-DEPEND=CL:764580

Change-Id: I13f0d2a23ea39c3249fa58ef7d7301595a1dea95
Reviewed-on: https://chromium-review.googlesource.com/764500
Commit-Ready: Guenter Roeck <groeck@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Kevin Cernekee <cernekee@chromium.org>

[modify] https://crrev.com/62dfc4fa19f20850cace0ab85da2529c0d0c980a/net/packet/af_packet.c

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/kernel/+/623b2e9f0fa2677dad61f7f33abef5d1e9a3a82b

commit 623b2e9f0fa2677dad61f7f33abef5d1e9a3a82b
Author: Willem de Bruijn <willemb@google.com>
Date: Tue Nov 21 23:58:38 2017

BACKPORT: packet: only test po->has_vnet_hdr once in packet_snd

[ Upstream commit da7c9561015e93d10fe6aab73e9288e0d09d65a6 ]

Packet socket option po->has_vnet_hdr can be updated concurrently with
other operations if no ring is attached.

Do not test the option twice in packet_snd, as the value may change in
between calls. A race on setsockopt disable may cause a packet > mtu
to be sent without having GSO options set.

Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 1299f7e17e9e442be49a9b6011f6fe5259960ebb)
Signed-off-by: Robert Kolchmeyer <rkolchmeyer@google.com>
[backport: context conflicts]
Signed-off-by: Guenter Roeck <groeck@chromium.org>

BUG=b:69149598, chromium:783729 
TEST=None

Change-Id: Ib13f113c8721597707bde35a9587aec8173e5606
Reviewed-on: https://chromium-review.googlesource.com/764580
Commit-Ready: Guenter Roeck <groeck@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Kevin Cernekee <cernekee@chromium.org>

[modify] https://crrev.com/623b2e9f0fa2677dad61f7f33abef5d1e9a3a82b/net/packet/af_packet.c

This bug has been closed for more than 14 weeks. Removing security view restrictions.

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