Commit Graph

54447 Commits

Author SHA1 Message Date
Matteo Croce
fe19a8fea7 ipvs: avoid indirect calls when calculating checksums
The function pointer ip_vs_protocol->csum_check is only used in protocol
specific code, and never in the generic one.
Remove the function pointer from struct ip_vs_protocol and call the
checksum functions directly.
This reduces the performance impact of the Spectre mitigation, and
should give a small improvement even with RETPOLINES disabled.

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-28 11:15:58 +01:00
Florian Westphal
e2f7cc72cb netfilter: conntrack: fix bogus port values for other l4 protocols
We must only extract l4 proto information if we can track the layer 4
protocol.

Before removal of pkt_to_tuple callback, the code to extract port
information was only reached for TCP/UDP/LITE/DCCP/SCTP.

The other protocols were handled by the indirect call, and the
'generic' tracker took care of other protocols that have no notion
of 'ports'.

After removal of the callback we must be more strict here and only
init port numbers for those protocols that have ports.

Fixes: df5e162908 ("netfilter: conntrack: remove pkt_to_tuple callback")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-22 23:28:40 +01:00
Florian Westphal
81e01647fd netfilter: conntrack: fix IPV6=n builds
Stephen Rothwell reports:
 After merging the netfilter-next tree, today's linux-next build
 (powerpc ppc64_defconfig) failed like this:

 ERROR: "nf_conntrack_invert_icmpv6_tuple" [nf_conntrack.ko] undefined!
 ERROR: "nf_conntrack_icmpv6_packet" [nf_conntrack.ko] undefined!
 ERROR: "nf_conntrack_icmpv6_init_net" [nf_conntrack.ko] undefined!
 ERROR: "icmpv6_pkt_to_tuple" [nf_conntrack.ko] undefined!
 ERROR: "nf_ct_gre_keymap_destroy" [nf_conntrack.ko] undefined!

icmpv6 related errors are due to lack of IS_ENABLED(CONFIG_IPV6) (no
icmpv6 support is builtin if kernel has CONFIG_IPV6=n), the
nf_ct_gre_keymap_destroy error is due to lack of PROTO_GRE check.

Fixes: a47c540481 ("netfilter: conntrack: handle builtin l4proto packet functions via direct calls")
Fixes: e2e48b4716 ("netfilter: conntrack: handle icmp pkt_to_tuple helper via direct calls")
Fixes: 197c4300ae ("netfilter: conntrack: remove invert_tuple callback")
Fixes: 2a389de86e ("netfilter: conntrack: remove l4proto init and get_net callbacks")
Fixes: e56894356f ("netfilter: conntrack: remove l4proto destroy hook")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-22 23:28:24 +01:00
Laura Garcia Liebana
0123a75e1d Revert "netfilter: nft_hash: add map lookups for hashing operations"
A better way to implement this from userspace has been found without
specific code in the kernel side, revert this.

Fixes: b9ccc07e3f ("netfilter: nft_hash: add map lookups for hashing operations")
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:59:47 +01:00
Florian Westphal
472caa6918 netfilter: nat: un-export nf_nat_used_tuple
Not used since 203f2e7820 ("netfilter: nat: remove l4proto->unique_tuple")

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:59:45 +01:00
wenxu
0fb4d21956 netfilter: nft_meta: Add NFT_META_I/OIFKIND meta type
In the ip_rcv the skb goes through the PREROUTING hook first, then kicks
in vrf device and go through the same hook again. When conntrack dnat
works with vrf, there will be some conflict with rules because the
packet goes through the hook twice with different nf status.

ip link add user1 type vrf table 1
ip link add user2 type vrf table 2
ip l set dev tun1 master user1
ip l set dev tun2 master user2

nft add table firewall
nft add chain firewall zones { type filter hook prerouting  priority - 300 \; }
nft add rule firewall zones counter ct zone set iif map { "tun1" : 1, "tun2" : 2 }
nft add chain firewall rule-1000-ingress
nft add rule firewall rule-1000-ingress ct zone 1 tcp dport 22 ct state new counter accept
nft add rule firewall rule-1000-ingress counter drop
nft add chain firewall rule-1000-egress
nft add rule firewall rule-1000-egress tcp dport 22 ct state new counter drop
nft add rule firewall rule-1000-egress counter accept

nft add chain firewall rules-all { type filter hook prerouting priority - 150 \; }
nft add rule firewall rules-all ip daddr vmap { "2.2.2.11" : jump rule-1000-ingress }
nft add rule firewall rules-all ct zone vmap { 1 : jump rule-1000-egress }

nft add rule firewall dnat-all ct zone vmap { 1 : jump dnat-1000 }
nft add rule firewall dnat-1000 ip daddr 2.2.2.11 counter dnat to 10.0.0.7

For a package with ip daddr 2.2.2.11 and tcp dport 22, first time accept in the
rule-1000-ingress and dnat to 10.0.0.7. Then second time the packet goto the wrong
chain rule-1000-egress which leads the packet drop

With this patch, userspace can add the 'don't re-do entire ruleset for
vrf' policy itself via:

nft add rule firewall rules-all meta iifkind "vrf" counter accept

Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:58:20 +01:00
Pablo Neira Ayuso
ba3fbe6636 netfilter: nf_conntrack: provide modparam to always register conntrack hooks
The connection tracking hooks can be optionally registered per netns
when conntrack is specifically invoked from the ruleset since
0c66dc1ea3 ("netfilter: conntrack: register hooks in netns when needed
by ruleset"). Then, since 4d3a57f23d ("netfilter: conntrack: do not
enable connection tracking unless needed"), the default behaviour is
changed to always register them on demand.

This patch provides a toggle that allows users to always register them.
Without this toggle, in order to use conntrack for statistics
collection, you need a dummy rule that refers to conntrack, eg.

        iptables -I INPUT -m state --state NEW

This patch allows users to restore the original behaviour via modparam,
ie. always register connection tracking, eg.

        modprobe nf_conntrack enable_hooks=1

Hence, no dummy rule is required.

Reported-by: Laura Garcia <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
4a60dc748d netfilter: conntrack: remove nf_ct_l4proto_find_get
Its now same as __nf_ct_l4proto_find(), so rename that to
nf_ct_l4proto_find and use it everywhere.

It never returns NULL and doesn't need locks or reference counts.

Before this series:
302824  net/netfilter/nf_conntrack.ko
 21504  net/netfilter/nf_conntrack_proto_gre.ko

  text	   data	    bss	    dec	    hex	filename
  6281	   1732	      4	   8017	   1f51	nf_conntrack_proto_gre.ko
108356	  20613	    236	 129205	  1f8b5	nf_conntrack.ko

After:
294864  net/netfilter/nf_conntrack.ko
  text	   data	    bss	    dec	    hex	filename
106979	  19557	    240	 126776	  1ef38	nf_conntrack.ko

so, even with builtin gre, total size got reduced.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
e56894356f netfilter: conntrack: remove l4proto destroy hook
Only one user (gre), add a direct call and remove this facility.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
2a389de86e netfilter: conntrack: remove l4proto init and get_net callbacks
Those were needed we still had modular trackers.
As we don't have those anymore, prefer direct calls and remove all
the (un)register infrastructure associated with this.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
70aed4647c netfilter: conntrack: remove sysctl registration helpers
After previous patch these are not used anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
b884fa4617 netfilter: conntrack: unify sysctl handling
Due to historical reasons, all l4 trackers register their own
sysctls.

This leads to copy&pasted boilerplate code, that does exactly same
thing, just with different data structure.

Place all of this in a single file.

This allows to remove the various ctl_table pointers from the ct_netns
structure and reduces overall code size.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
303e0c5589 netfilter: conntrack: avoid unneeded nf_conntrack_l4proto lookups
after removal of the packet and invert function pointers, several
places do not need to lookup the l4proto structure anymore.

Remove those lookups.
The function nf_ct_invert_tuplepr becomes redundant, replace
it with nf_ct_invert_tuple everywhere.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
edf0338dab netfilter: conntrack: remove pernet l4 proto register interface
No used anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
44fb87f635 netfilter: conntrack: remove remaining l4proto indirect packet calls
Now that all l4trackers are builtin, no need to use a mix of direct and
indirect calls.
This removes the last two users: gre and the generic l4 protocol
tracker.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
b184356d0a netfilter: conntrack: remove module owner field
No need to get/put module owner reference, none of these can be removed
anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
197c4300ae netfilter: conntrack: remove invert_tuple callback
Only used by icmp(v6).  Prefer a direct call and remove this
function from the l4proto struct.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
df5e162908 netfilter: conntrack: remove pkt_to_tuple callback
GRE is now builtin, so we can handle it via direct call and
remove the callback.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
751fc301ec netfilter: conntrack: remove net_id
No users anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
22fc4c4c9f netfilter: conntrack: gre: switch module to be built-in
This makes the last of the modular l4 trackers 'bool'.

After this, all infrastructure to handle dynamic l4 protocol registration
becomes obsolete and can be removed in followup patches.

Old:
302824 net/netfilter/nf_conntrack.ko
 21504 net/netfilter/nf_conntrack_proto_gre.ko

New:
313728 net/netfilter/nf_conntrack.ko

Old:
   text	   data	    bss	    dec	    hex	filename
   6281	   1732	      4	   8017	   1f51	nf_conntrack_proto_gre.ko
 108356	  20613	    236	 129205	  1f8b5	nf_conntrack.ko
New:
 112095	  21381	    240	 133716	  20a54	nf_conntrack.ko

The size increase is only temporary.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
202e651cd4 netfilter: conntrack: gre: convert rwlock to rcu
We can use gre.  Lock is only needed when a new expectation is added.

In case a single spinlock proves to be problematic we can either add one
per netns or use an array of locks combined with net_hash_mix() or similar
to pick the 'correct' one.

But given this is only needed for an expectation rather than per packet
a single one should be ok.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
e2e48b4716 netfilter: conntrack: handle icmp pkt_to_tuple helper via direct calls
rather than handling them via indirect call, use a direct one instead.
This leaves GRE as the last user of this indirect call facility.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
a47c540481 netfilter: conntrack: handle builtin l4proto packet functions via direct calls
The l4 protocol trackers are invoked via indirect call: l4proto->packet().

With one exception (gre), all l4trackers are builtin, so we can make
.packet optional and use a direct call for most protocols.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Phil Sutter
75dd48e2e4 netfilter: nf_tables: Support RULE_ID reference in new rule
To allow for a batch to contain rules in arbitrary ordering, introduce
NFTA_RULE_POSITION_ID attribute which works just like NFTA_RULE_POSITION
but contains the ID of another rule within the same batch. This helps
iptables-nft-restore handling dumps with mixed insert/append commands
correctly.

Note that NFTA_RULE_POSITION takes precedence over
NFTA_RULE_POSITION_ID, so if the former is present, the latter is
ignored.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
8e2f311a68 netfilter: physdev: relax br_netfilter dependency
Following command:
  iptables -D FORWARD -m physdev ...
causes connectivity loss in some setups.

Reason is that iptables userspace will probe kernel for the module revision
of the physdev patch, and physdev has an artificial dependency on
br_netfilter (xt_physdev use makes no sense unless a br_netfilter module
is loaded).

This causes the "phydev" module to be loaded, which in turn enables the
"call-iptables" infrastructure.

bridged packets might then get dropped by the iptables ruleset.

The better fix would be to change the "call-iptables" defaults to 0 and
enforce explicit setting to 1, but that breaks backwards compatibility.

This does the next best thing: add a request_module call to checkentry.
This was a stray '-D ... -m physdev' won't activate br_netfilter
anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
827318feb6 netfilter: conntrack: remove helper hook again
place them into the confirm one.

Old:
 hook (300): ipv4/6_help() first call helper, then seqadj.
 hook (INT_MAX): confirm

Now:
 hook (INT_MAX): confirm, first call helper, then seqadj, then confirm

Not having the extra call is noticeable in bechmarks.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
10870dd89e netfilter: nf_tables: add direct calls for all builtin expressions
With CONFIG_RETPOLINE its faster to add an if (ptr == &foo_func)
check and and use direct calls for all the built-in expressions.

~15% improvement in pathological cases.

checkpatch doesn't like the X macro due to the embedded return statement,
but the macro has a very limited scope so I don't think its a problem.

I would like to avoid bugs of the form
  If (e->ops->eval == (unsigned long)nft_foo_eval)
	 nft_bar_eval();

and open-coded if ()/else if()/else cascade, thus the macro.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
4d44175aa5 netfilter: nf_tables: handle nft_object lookups via rhltable
Instead of linear search, use rhlist interface to look up the objects.
This fixes rulesets with thousands of named objects (quota, counters and
the like).

We only use a single table for this and consider the address of the
table we're doing the lookup in as a part of the key.

This reduces restore time of a sample ruleset with ~20k named counters
from 37 seconds to 0.8 seconds.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal
d152159b89 netfilter: nf_tables: prepare nft_object for lookups via hashtable
Add a 'key' structure for object, so we can look them up by name + table
combination (the name can be the same in each table).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:32 +01:00
Eric Dumazet
6bcdc40ddd tcp: move rx_opt & syn_data_acked init to tcp_disconnect()
If we make sure all listeners have these fields cleared, then a clone
will also inherit zero values.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
792c4354a5 tcp: move tp->rack init to tcp_disconnect()
If we make sure all listeners have proper tp->rack value,
then a clone will also inherit proper initial value.

Note that fresh sockets init tp->rack from tcp_init_sock()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
6cda8b7493 tcp: move app_limited init to tcp_disconnect()
If we make sure all listeners have app_limited set to ~0U,
then a clone will also inherit proper initial value.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
5c701549c9 tcp: move retrans_out, sacked_out, tlp_high_seq, last_oow_ack_time init to tcp_disconnect()
If we make sure all listeners have these fields cleared, then a clone
will also inherit zero values.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
5d83676462 tcp: do not clear urg_data in tcp_create_openreq_child
All listeners have this field cleared already, since tcp_disconnect()
clears it and newly created sockets have also a zero value here.

So a clone will inherit a zero value here.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
3a9a57f637 tcp: move snd_cwnd & snd_cwnd_cnt init to tcp_disconnect()
Passive connections can inherit proper value by cloning,
if we make sure all listeners have the proper values there.

tcp_disconnect() was setting snd_cwnd to 2, which seems
quite obsolete since IW10 adoption.

Also remove an obsolete comment.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
b9e2e689aa tcp: move mdev_us init to tcp_disconnect()
If we make sure a listener always has its mdev_us
field set to TCP_TIMEOUT_INIT, we do not need to rewrite
this field after a new clone is created.

tcp_disconnect() is very seldom used in real applications.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
a0070e463f tcp: do not clear srtt_us in tcp_create_openreq_child
All listeners have this field cleared already, since tcp_disconnect()
clears it and newly created sockets have also a zero value here.

So a clone will inherit a zero value here.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:05 -08:00
Eric Dumazet
eb2c80ca87 tcp: do not clear packets_out in tcp_create_openreq_child()
New sockets have this field cleared, and tcp_disconnect()
calls tcp_write_queue_purge() which among other things
also clear tp->packets_out

So a listener is guaranteed to have this field cleared.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:04 -08:00
Eric Dumazet
6a408147ea tcp: move icsk_rto init to tcp_disconnect()
If we make sure a listener always has its icsk_rto
field set to TCP_TIMEOUT_INIT, we do not need to rewrite
this field after a new clone is created.

tcp_disconnect() is very seldom used in real applications.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:04 -08:00
Eric Dumazet
b84235e291 tcp: do not set snd_ssthresh in tcp_create_openreq_child()
New sockets get the field set to TCP_INFINITE_SSTHRESH in tcp_init_sock()
In case a socket had this field changed and transitions to TCP_LISTEN
state, tcp_disconnect() also makes sure snd_ssthresh is set to
TCP_INFINITE_SSTHRESH.

So a listener has this field set to TCP_INFINITE_SSTHRESH already.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:19:04 -08:00
YueHaibing
d4fb30f6f1 tipc: remove unneeded semicolon in trace.c
Remove unneeded semicolon

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:04:43 -08:00
Peter Oskolkov
22c2ad616b net: add a route cache full diagnostic message
In some testing scenarios, dst/route cache can fill up so quickly
that even an explicit GC call occasionally fails to clean it up. This leads
to sporadically failing calls to dst_alloc and "network unreachable" errors
to the user, which is confusing.

This patch adds a diagnostic message to make the cause of the failure
easier to determine.

Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:37:25 -08:00
Petr Machata
6685987c29 switchdev: Add extack argument to call_switchdev_notifiers()
A follow-up patch will enable vetoing of FDB entries. Make it possible
to communicate details of why an FDB entry is not acceptable back to the
user.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:18:47 -08:00
Petr Machata
87b0984ebf net: Add extack argument to ndo_fdb_add()
Drivers may not be able to support certain FDB entries, and an error
code is insufficient to give clear hints as to the reasons of rejection.

In order to make it possible to communicate the rejection reason, extend
ndo_fdb_add() with an extack argument. Adapt the existing
implementations of ndo_fdb_add() to take the parameter (and ignore it).
Pass the extack parameter when invoking ndo_fdb_add() from rtnl_fdb_add().

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:18:47 -08:00
Yuchung Cheng
c1d5674f83 tcp: less aggressive window probing on local congestion
Previously when the sender fails to send (original) data packet or
window probes due to congestion in the local host (e.g. throttling
in qdisc), it'll retry within an RTO or two up to 500ms.

In low-RTT networks such as data-centers, RTO is often far below
the default minimum 200ms. Then local host congestion could trigger
a retry storm pouring gas to the fire. Worse yet, the probe counter
(icsk_probes_out) is not properly updated so the aggressive retry
may exceed the system limit (15 rounds) until the packet finally
slips through.

On such rare events, it's wise to retry more conservatively
(500ms) and update the stats properly to reflect these incidents
and follow the system limit. Note that this is consistent with
the behaviors when a keep-alive probe or RTO retry is dropped
due to local congestion.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:12:26 -08:00
Yuchung Cheng
590d2026d6 tcp: retry more conservatively on local congestion
Previously when the sender fails to retransmit a data packet on
timeout due to congestion in the local host (e.g. throttling in
qdisc), it'll retry within an RTO up to 500ms.

In low-RTT networks such as data-centers, RTO is often far
below the default minimum 200ms (and the cap 500ms). Then local
host congestion could trigger a retry storm pouring gas to the
fire. Worse yet, the retry counter (icsk_retransmits) is not
properly updated so the aggressive retry may exceed the system
limit (15 rounds) until the packet finally slips through.

On such rare events, it's wise to retry more conservatively (500ms)
and update the stats properly to reflect these incidents and follow
the system limit. Note that this is consistent with the behavior
when a keep-alive probe is dropped due to local congestion.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:12:26 -08:00
Yuchung Cheng
9721e709fa tcp: simplify window probe aborting on USER_TIMEOUT
Previously we use the next unsent skb's timestamp to determine
when to abort a socket stalling on window probes. This no longer
works as skb timestamp reflects the last instead of the first
transmission.

Instead we can estimate how long the socket has been stalling
with the probe count and the exponential backoff behavior.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:12:26 -08:00
Yuchung Cheng
01a523b071 tcp: create a helper to model exponential backoff
Create a helper to model TCP exponential backoff for the next patch.
This is pure refactor w no behavior change.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:12:26 -08:00
Yuchung Cheng
c7d13c8faa tcp: properly track retry time on passive Fast Open
This patch addresses a corner issue on timeout behavior of a
passive Fast Open socket.  A passive Fast Open server may write
and close the socket when it is re-trying SYN-ACK to complete
the handshake. After the handshake is completely, the server does
not properly stamp the recovery start time (tp->retrans_stamp is
0), and the socket may abort immediately on the very first FIN
timeout, instead of retying until it passes the system or user
specified limit.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:12:26 -08:00
Yuchung Cheng
7ae189759c tcp: always set retrans_stamp on recovery
Previously TCP socket's retrans_stamp is not set if the
retransmission has failed to send. As a result if a socket is
experiencing local issues to retransmit packets, determining when
to abort a socket is complicated w/o knowning the starting time of
the recovery since retrans_stamp may remain zero.

This complication causes sub-optimal behavior that TCP may use the
latest, instead of the first, retransmission time to compute the
elapsed time of a stalling connection due to local issues. Then TCP
may disrecard TCP retries settings and keep retrying until it finally
succeed: not a good idea when the local host is already strained.

The simple fix is to always timestamp the start of a recovery.
It's worth noting that retrans_stamp is also used to compare echo
timestamp values to detect spurious recovery. This patch does
not break that because retrans_stamp is still later than when the
original packet was sent.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:12:26 -08:00