linux.git/net/ipv4, branch v4.16-rc4

net: ipv4: Set addr_type in hash_keys for forwarded case

2018-02-22T19:30:51+00:00

The result of the skb flow dissect is copied from keys to hash_keys to
ensure only the intended data is hashed. The original L4 hash patch
overlooked setting the addr_type for this case; add it.

Fixes: bf4e0a3db97eb ("net: ipv4: add support for ECMP hash policy choice")
Reported-by: Ido Schimmel 
Signed-off-by: David Ahern 
Acked-by: Nikolay Aleksandrov 
Reviewed-by: Ido Schimmel 
Signed-off-by: David S. Miller

tcp_bbr: better deal with suboptimal GSO

2018-02-22T19:15:23+00:00

BBR uses tcp_tso_autosize() in an attempt to probe what would be the
burst sizes and to adjust cwnd in bbr_target_cwnd() with following
gold formula :

/* Allow enough full-sized skbs in flight to utilize end systems. */
cwnd += 3 * bbr->tso_segs_goal;

But GSO can be lacking or be constrained to very small
units (ip link set dev ... gso_max_segs 2)

What we really want is to have enough packets in flight so that both
GSO and GRO are efficient.

So in the case GSO is off or downgraded, we still want to have the same
number of packets in flight as if GSO/TSO was fully operational, so
that GRO can hopefully be working efficiently.

To fix this issue, we make tcp_tso_autosize() unaware of
sk->sk_gso_max_segs

Only tcp_tso_segs() has to enforce the gso_max_segs limit.

Tested:

ethtool -K eth0 tso off gso off
tc qd replace dev eth0 root pfifo_fast

Before patch:
for f in {1..5}; do ./super_netperf 1 -H lpaa24 -- -K bbr; done
    691  (ss -temoi shows cwnd is stuck around 6 )
    667
    651
    631
    517

After patch :
# for f in {1..5}; do ./super_netperf 1 -H lpaa24 -- -K bbr; done
   1733 (ss -temoi shows cwnd is around 386 )
   1778
   1746
   1781
   1718

Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control")
Signed-off-by: Eric Dumazet 
Reported-by: Oleksandr Natalenko 
Acked-by: Neal Cardwell 
Acked-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller

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

2018-02-21T19:49:55+00:00

Pablo Neira Ayuso says:

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

The following patchset contains large batch with Netfilter fixes for
your net tree, mostly due to syzbot report fixups and pr_err()
ratelimiting, more specifically, they are:

1) Get rid of superfluous unnecessary check in x_tables before vmalloc(),
   we don't hit BUG there anymore, patch from Michal Hock, suggested by
   Andrew Morton.

2) Race condition in proc file creation in ipt_CLUSTERIP, from Cong Wang.

3) Drop socket lock that results in circular locking dependency, patch
   from Paolo Abeni.

4) Drop packet if case of malformed blob that makes backpointer jump
   in x_tables, from Florian Westphal.

5) Fix refcount leak due to race in ipt_CLUSTERIP in
   clusterip_config_find_get(), from Cong Wang.

6) Several patches to ratelimit pr_err() for x_tables since this can be
   a problem where CAP_NET_ADMIN semantics can protect us in untrusted
   namespace, from Florian Westphal.

7) Missing .gitignore update for new autogenerated asn1 state machine
   for the SNMP NAT helper, from Zhu Lingshan.

8) Missing timer initialization in xt_LED, from Paolo Abeni.

9) Do not allow negative port range in NAT, also from Paolo.

10) Lock imbalance in the xt_hashlimit rate match mode, patch from
    Eric Dumazet.

11) Initialize workqueue before timer in the idletimer match,
    from Eric Dumazet.
====================

Signed-off-by: David S. Miller

udplite: fix partial checksum initialization

2018-02-16T20:57:42+00:00

Since UDP-Lite is always using checksum, the following path is
triggered when calculating pseudo header for it:

  udp4_csum_init() or udp6_csum_init()
    skb_checksum_init_zero_check()
      __skb_checksum_validate_complete()

The problem can appear if skb->len is less than CHECKSUM_BREAK. In
this particular case __skb_checksum_validate_complete() also invokes
__skb_checksum_complete(skb). If UDP-Lite is using partial checksum
that covers only part of a packet, the function will return bad
checksum and the packet will be dropped.

It can be fixed if we skip skb_checksum_init_zero_check() and only
set the required pseudo header checksum for UDP-Lite with partial
checksum before udp4_csum_init()/udp6_csum_init() functions return.

Fixes: ed70fcfcee95 ("net: Call skb_checksum_init in IPv4")
Fixes: e4f45b7f40bd ("net: Call skb_checksum_init in IPv6")
Signed-off-by: Alexey Kodanev 
Signed-off-by: David S. Miller

fib_semantics: Don't match route with mismatching tclassid

2018-02-16T20:19:54+00:00

In fib_nh_match(), if output interface or gateway are passed in
the FIB configuration, we don't have to check next hops of
multipath routes to conclude whether we have a match or not.

However, we might still have routes with different realms
matching the same output interface and gateway configuration,
and this needs to cause the match to fail. Otherwise the first
route inserted in the FIB will match, regardless of the realms:

 # ip route add 1.1.1.1 dev eth0 table 1234 realms 1/2
 # ip route append 1.1.1.1 dev eth0 table 1234 realms 3/4
 # ip route list table 1234
 1.1.1.1 dev eth0 scope link realms 1/2
 1.1.1.1 dev eth0 scope link realms 3/4
 # ip route del 1.1.1.1 dev ens3 table 1234 realms 3/4
 # ip route list table 1234
 1.1.1.1 dev ens3 scope link realms 3/4

whereas route with realms 3/4 should have been deleted instead.

Explicitly check for fc_flow passed in the FIB configuration
(this comes from RTA_FLOW extracted by rtm_to_fib_config()) and
fail matching if it differs from nh_tclassid.

The handling of RTA_FLOW for multipath routes later in
fib_nh_match() is still needed, as we can have multiple RTA_FLOW
attributes that need to be matched against the tclassid of each
next hop.

v2: Check that fc_flow is set before discarding the match, so
    that the user can still select the first matching rule by
    not specifying any realm, as suggested by David Ahern.

Reported-by: Jianlin Shi 
Signed-off-by: Stefano Brivio 
Acked-by: David Ahern 
Signed-off-by: David S. Miller

netfilter: x_tables: use pr ratelimiting in all remaining spots

2018-02-14T20:05:38+00:00

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: x_tables: rate-limit table mismatch warnings

2018-02-14T20:05:36+00:00

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: x_tables: remove pr_info where possible

2018-02-14T20:05:33+00:00

remove several pr_info messages that cannot be triggered with iptables,
the check is only to ensure input is sane.

iptables(8) already prints error messages in these cases.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: ipt_CLUSTERIP: fix a refcount bug in clusterip_config_find_get()

2018-02-14T20:05:32+00:00

In clusterip_config_find_get() we hold RCU read lock so it could
run concurrently with clusterip_config_entry_put(), as a result,
the refcnt could go back to 1 from 0, which leads to a double
list_del()... Just replace refcount_inc() with
refcount_inc_not_zero(), as for c->refcount.

Fixes: d73f33b16883 ("netfilter: CLUSTERIP: RCU conversion")
Cc: Eric Dumazet 
Cc: Pablo Neira Ayuso 
Cc: Florian Westphal 
Signed-off-by: Cong Wang 
Reviewed-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: add back stackpointer size checks

2018-02-14T19:47:41+00:00

The rationale for removing the check is only correct for rulesets
generated by ip(6)tables.

In iptables, a jump can only occur to a user-defined chain, i.e.
because we size the stack based on number of user-defined chains we
cannot exceed stack size.

However, the underlying binary format has no such restriction,
and the validation step only ensures that the jump target is a
valid rule start point.

IOW, its possible to build a rule blob that has no user-defined
chains but does contain a jump.

If this happens, no jump stack gets allocated and crash occurs
because no jumpstack was allocated.

Fixes: 7814b6ec6d0d6 ("netfilter: xtables: don't save/restore jumpstack offset")
Reported-by: syzbot+e783f671527912cd9403@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso