linux-toradex.git/net/ipv4, branch v4.6-rc5

tcp: Merge tx_flags and tskey in tcp_shifted_skb

2016-04-21T18:40:55+00:00

After receiving sacks, tcp_shifted_skb() will collapse
skbs if possible.  tx_flags and tskey also have to be
merged.

This patch reuses the tcp_skb_collapse_tstamp() to handle
them.

BPF Output Before:
~~~~~


BPF Output After:
~~~~~
<...>-2024  [007] d.s.    88.644374: : ee_data:14599

Packetdrill Script:
~~~~~
+0 `sysctl -q -w net.ipv4.tcp_min_tso_segs=10`
+0 `sysctl -q -w net.ipv4.tcp_no_metrics_save=1`
+0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0 bind(3, ..., ...) = 0
+0 listen(3, 1) = 0

0.100 < S 0:0(0) win 32792 
0.100 > S. 0:0(0) ack 1 
0.200 < . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4
+0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0

0.200 write(4, ..., 1460) = 1460
+0 setsockopt(4, SOL_SOCKET, 37, [2688], 4) = 0
0.200 write(4, ..., 13140) = 13140

0.200 > P. 1:1461(1460) ack 1
0.200 > . 1461:8761(7300) ack 1
0.200 > P. 8761:14601(5840) ack 1

0.300 < . 1:1(0) ack 1 win 257 
0.300 > P. 1:1461(1460) ack 1
0.400 < . 1:1(0) ack 14601 win 257

0.400 close(4) = 0
0.400 > F. 14601:14601(0) ack 1
0.500 < F. 1:1(0) ack 14602 win 257
0.500 > . 14602:14602(0) ack 2

Signed-off-by: Martin KaFai Lau 
Cc: Eric Dumazet 
Cc: Neal Cardwell 
Cc: Soheil Hassas Yeganeh 
Cc: Willem de Bruijn 
Cc: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Tested-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller

tcp: Merge tx_flags and tskey in tcp_collapse_retrans

2016-04-21T18:40:55+00:00

If two skbs are merged/collapsed during retransmission, the current
logic does not merge the tx_flags and tskey.  The end result is
the SCM_TSTAMP_ACK timestamp could be missing for a packet.

The patch:
1. Merge the tx_flags
2. Overwrite the prev_skb's tskey with the next_skb's tskey

BPF Output Before:
~~~~~~


BPF Output After:
~~~~~~
packetdrill-2092  [001] d.s.   453.998486: : ee_data:1459

Packetdrill Script:
~~~~~~
+0 `sysctl -q -w net.ipv4.tcp_min_tso_segs=10`
+0 `sysctl -q -w net.ipv4.tcp_no_metrics_save=1`
+0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0 bind(3, ..., ...) = 0
+0 listen(3, 1) = 0

0.100 < S 0:0(0) win 32792 
0.100 > S. 0:0(0) ack 1 
0.200 < . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4
+0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0

0.200 write(4, ..., 730) = 730
+0 setsockopt(4, SOL_SOCKET, 37, [2688], 4) = 0
0.200 write(4, ..., 730) = 730
+0 setsockopt(4, SOL_SOCKET, 37, [2176], 4) = 0
0.200 write(4, ..., 11680) = 11680
+0 setsockopt(4, SOL_SOCKET, 37, [2688], 4) = 0

0.200 > P. 1:731(730) ack 1
0.200 > P. 731:1461(730) ack 1
0.200 > . 1461:8761(7300) ack 1
0.200 > P. 8761:13141(4380) ack 1

0.300 < . 1:1(0) ack 1 win 257 
0.300 < . 1:1(0) ack 1 win 257 
0.300 < . 1:1(0) ack 1 win 257 
0.300 > P. 1:1461(1460) ack 1
0.400 < . 1:1(0) ack 13141 win 257

0.400 close(4) = 0
0.400 > F. 13141:13141(0) ack 1
0.500 < F. 1:1(0) ack 13142 win 257
0.500 > . 13142:13142(0) ack 2

Signed-off-by: Martin KaFai Lau 
Cc: Eric Dumazet 
Cc: Neal Cardwell 
Cc: Soheil Hassas Yeganeh 
Cc: Willem de Bruijn 
Cc: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Tested-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller

tcp: Fix SOF_TIMESTAMPING_TX_ACK when handling dup acks

2016-04-21T17:45:43+00:00

Assuming SOF_TIMESTAMPING_TX_ACK is on. When dup acks are received,
it could incorrectly think that a skb has already
been acked and queue a SCM_TSTAMP_ACK cmsg to the
sk->sk_error_queue.

In tcp_ack_tstamp(), it checks
'between(shinfo->tskey, prior_snd_una, tcp_sk(sk)->snd_una - 1)'.
If prior_snd_una == tcp_sk(sk)->snd_una like the following packetdrill
script, between() returns true but the tskey is actually not acked.
e.g. try between(3, 2, 1).

The fix is to replace between() with one before() and one !before().
By doing this, the -1 offset on the tcp_sk(sk)->snd_una can also be
removed.

A packetdrill script is used to reproduce the dup ack scenario.
Due to the lacking cmsg support in packetdrill (may be I
cannot find it),  a BPF prog is used to kprobe to
sock_queue_err_skb() and print out the value of
serr->ee.ee_data.

Both the packetdrill and the bcc BPF script is attached at the end of
this commit message.

BPF Output Before Fix:
~~~~~~
      <...>-2056  [001] d.s.   433.927987: : ee_data:1459  #incorrect
packetdrill-2056  [001] d.s.   433.929563: : ee_data:1459  #incorrect
packetdrill-2056  [001] d.s.   433.930765: : ee_data:1459  #incorrect
packetdrill-2056  [001] d.s.   434.028177: : ee_data:1459
packetdrill-2056  [001] d.s.   434.029686: : ee_data:14599

BPF Output After Fix:
~~~~~~
      <...>-2049  [000] d.s.   113.517039: : ee_data:1459
      <...>-2049  [000] d.s.   113.517253: : ee_data:14599

BCC BPF Script:
~~~~~~
#!/usr/bin/env python

from __future__ import print_function
from bcc import BPF

bpf_text = """
#include 
#include 
#include 
#include 

#ifdef memset
#undef memset
#endif

int trace_err_skb(struct pt_regs *ctx)
{
	struct sk_buff *skb = (struct sk_buff *)ctx->si;
	struct sock *sk = (struct sock *)ctx->di;
	struct sock_exterr_skb *serr;
	u32 ee_data = 0;

	if (!sk || !skb)
		return 0;

	serr = SKB_EXT_ERR(skb);
	bpf_probe_read(&ee_data, sizeof(ee_data), &serr->ee.ee_data);
	bpf_trace_printk("ee_data:%u\\n", ee_data);

	return 0;
};
"""

b = BPF(text=bpf_text)
b.attach_kprobe(event="sock_queue_err_skb", fn_name="trace_err_skb")
print("Attached to kprobe")
b.trace_print()

Packetdrill Script:
~~~~~~
+0 `sysctl -q -w net.ipv4.tcp_min_tso_segs=10`
+0 `sysctl -q -w net.ipv4.tcp_no_metrics_save=1`
+0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0 bind(3, ..., ...) = 0
+0 listen(3, 1) = 0

0.100 < S 0:0(0) win 32792 
0.100 > S. 0:0(0) ack 1 
0.200 < . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4
+0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0

+0 setsockopt(4, SOL_SOCKET, 37, [2688], 4) = 0
0.200 write(4, ..., 1460) = 1460
0.200 write(4, ..., 13140) = 13140

0.200 > P. 1:1461(1460) ack 1
0.200 > . 1461:8761(7300) ack 1
0.200 > P. 8761:14601(5840) ack 1

0.300 < . 1:1(0) ack 1 win 257 
0.300 < . 1:1(0) ack 1 win 257 
0.300 < . 1:1(0) ack 1 win 257 
0.300 > P. 1:1461(1460) ack 1
0.400 < . 1:1(0) ack 14601 win 257

0.400 close(4) = 0
0.400 > F. 14601:14601(0) ack 1
0.500 < F. 1:1(0) ack 14602 win 257
0.500 > . 14602:14602(0) ack 2

Signed-off-by: Martin KaFai Lau 
Cc: Eric Dumazet 
Cc: Neal Cardwell 
Cc: Soheil Hassas Yeganeh 
Cc: Willem de Bruijn 
Cc: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Tested-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller

soreuseport: fix ordering for mixed v4/v6 sockets

2016-04-15T01:14:03+00:00

With the SO_REUSEPORT socket option, it is possible to create sockets
in the AF_INET and AF_INET6 domains which are bound to the same IPv4 address.
This is only possible with SO_REUSEPORT and when not using IPV6_V6ONLY on
the AF_INET6 sockets.

Prior to the commits referenced below, an incoming IPv4 packet would
always be routed to a socket of type AF_INET when this mixed-mode was used.
After those changes, the same packet would be routed to the most recently
bound socket (if this happened to be an AF_INET6 socket, it would
have an IPv4 mapped IPv6 address).

The change in behavior occurred because the recent SO_REUSEPORT optimizations
short-circuit the socket scoring logic as soon as they find a match.  They
did not take into account the scoring logic that favors AF_INET sockets
over AF_INET6 sockets in the event of a tie.

To fix this problem, this patch changes the insertion order of AF_INET
and AF_INET6 addresses in the TCP and UDP socket lists when the sockets
have SO_REUSEPORT set.  AF_INET sockets will be inserted at the head of the
list and AF_INET6 sockets with SO_REUSEPORT set will always be inserted at
the tail of the list.  This will force AF_INET sockets to always be
considered first.

Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection")
Fixes: 125e80b88687 ("soreuseport: fast reuseport TCP socket selection")

Reported-by: Maciej Żenczykowski 
Signed-off-by: Craig Gallek 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

route: do not cache fib route info on local routes with oif

2016-04-14T03:33:01+00:00

For local routes that require a particular output interface we do not want
to cache the result.  Caching the result causes incorrect behaviour when
there are multiple source addresses on the interface.  The end result
being that if the intended recipient is waiting on that interface for the
packet he won't receive it because it will be delivered on the loopback
interface and the IP_PKTINFO ipi_ifindex will be set to the loopback
interface as well.

This can be tested by running a program such as "dhcp_release" which
attempts to inject a packet on a particular interface so that it is
received by another program on the same board.  The receiving process
should see an IP_PKTINFO ipi_ifndex value of the source interface
(e.g., eth1) instead of the loopback interface (e.g., lo).  The packet
will still appear on the loopback interface in tcpdump but the important
aspect is that the CMSG info is correct.

Sample dhcp_release command line:

   dhcp_release eth1 192.168.204.222 02:11:33:22:44:66

Signed-off-by: Allain Legacy 
Signed off-by: Chris Friesen 
Reviewed-by: Julian Anastasov 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

2016-04-14T01:49:03+00:00

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree. More
specifically, they are:

1) Fix missing filter table per-netns registration in arptables, from
   Florian Westphal.

2) Resolve out of bound access when parsing TCP options in
   nf_conntrack_tcp, patch from Jozsef Kadlecsik.

3) Prefer NFPROTO_BRIDGE extensions over NFPROTO_UNSPEC in ebtables,
   this resolves conflict between xt_limit and ebt_limit, from Phil Sutter.
====================

Signed-off-by: David S. Miller

net: vrf: Fix dst reference counting

2016-04-11T19:56:20+00:00

Vivek reported a kernel exception deleting a VRF with an active
connection through it. The root cause is that the socket has a cached
reference to a dst that is destroyed. Converting the dst_destroy to
dst_release and letting proper reference counting kick in does not
work as the dst has a reference to the device which needs to be released
as well.

I talked to Hannes about this at netdev and he pointed out the ipv4 and
ipv6 dst handling has dst_ifdown for just this scenario. Rather than
continuing with the reinvented dst wheel in VRF just remove it and
leverage the ipv4 and ipv6 versions.

Fixes: 193125dbd8eb2 ("net: Introduce VRF device driver")
Fixes: 35402e3136634 ("net: Add IPv6 support to VRF device")

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

GRE: Disable segmentation offloads w/ CSUM and we are encapsulated via FOU

2016-04-07T20:56:33+00:00

This patch fixes an issue I found in which we were dropping frames if we
had enabled checksums on GRE headers that were encapsulated by either FOU
or GUE.  Without this patch I was barely able to get 1 Gb/s of throughput.
With this patch applied I am now at least getting around 6 Gb/s.

The issue is due to the fact that with FOU or GUE applied we do not provide
a transport offset pointing to the GRE header, nor do we offload it in
software as the GRE header is completely skipped by GSO and treated like a
VXLAN or GENEVE type header.  As such we need to prevent the stack from
generating it and also prevent GRE from generating it via any interface we
create.

Fixes: c3483384ee511 ("gro: Allow tunnel stacking in the case of FOU/GUE")
Signed-off-by: Alexander Duyck 
Signed-off-by: David S. Miller

netfilter: arp_tables: register table in initns

2016-04-07T09:58:49+00:00

arptables is broken since we didn't register the table anymore --
even 'arptables -L' fails.

Fixes: b9e69e127397187b ("netfilter: xtables: don't hook tables by default")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

gro: Allow tunnel stacking in the case of FOU/GUE

2016-03-30T20:02:33+00:00

This patch should fix the issues seen with a recent fix to prevent
tunnel-in-tunnel frames from being generated with GRO.  The fix itself is
correct for now as long as we do not add any devices that support
NETIF_F_GSO_GRE_CSUM.  When such a device is added it could have the
potential to mess things up due to the fact that the outer transport header
points to the outer UDP header and not the GRE header as would be expected.

Fixes: fac8e0f579695 ("tunnels: Don't apply GRO to multiple layers of encapsulation.")
Signed-off-by: Alexander Duyck 
Signed-off-by: David S. Miller