linux/include
David Ahern a04a480d43 net: Require exact match for TCP socket lookups if dif is l3mdev
Currently, socket lookups for l3mdev (vrf) use cases can match a socket
that is bound to a port but not a device (ie., a global socket). If the
sysctl tcp_l3mdev_accept is not set this leads to ack packets going out
based on the main table even though the packet came in from an L3 domain.
The end result is that the connection does not establish creating
confusion for users since the service is running and a socket shows in
ss output. Fix by requiring an exact dif to sk_bound_dev_if match if the
skb came through an interface enslaved to an l3mdev device and the
tcp_l3mdev_accept is not set.

skb's through an l3mdev interface are marked by setting a flag in
inet{6}_skb_parm. The IPv6 variant is already set; this patch adds the
flag for IPv4. Using an skb flag avoids a device lookup on the dif. The
flag is set in the VRF driver using the IP{6}CB macros. For IPv4, the
inet_skb_parm struct is moved in the cb per commit 971f10eca1, so the
match function in the TCP stack needs to use TCP_SKB_CB. For IPv6, the
move is done after the socket lookup, so IP6CB is used.

The flags field in inet_skb_parm struct needs to be increased to add
another flag. There is currently a 1-byte hole following the flags,
so it can be expanded to u16 without increasing the size of the struct.

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-17 10:17:05 -04:00
..
acpi
asm-generic Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-11 23:38:39 -07:00
clocksource
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-10-10 11:19:47 +08:00
drm drm/crtc: constify drm_crtc_index parameter 2016-10-10 17:28:58 +02:00
dt-bindings Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2016-10-12 11:05:23 -07:00
keys
kvm
linux net: Require exact match for TCP socket lookups if dif is l3mdev 2016-10-17 10:17:05 -04:00
math-emu
media
memory
misc
net net: Require exact match for TCP socket lookups if dif is l3mdev 2016-10-17 10:17:05 -04:00
pcmcia
ras
rdma Merge of primary rdma-core code for 4.9 2016-10-09 17:04:33 -07:00
rxrpc
scsi
soc
sound
target
trace
uapi ethtool: silence warning on bit loss 2016-10-14 16:05:42 -04:00
video fbdev changes for 4.9 2016-10-12 11:01:37 -07:00
xen
Kbuild