Commit Graph

6999 Commits

Author SHA1 Message Date
Andy Whitcroft 25b97c016b ipv4: off-by-one in continuation handling in /proc/net/route
When generating /proc/net/route we emit a header followed by a line for
each route.  When a short read is performed we will restart this process
based on the open file descriptor.  When calculating the start point we
fail to take into account that the 0th entry is the header.  This leads
us to skip the first entry when doing a continuation read.

This can be easily seen with the comparison below:

  while read l; do echo "$l"; done </proc/net/route >A
  cat /proc/net/route >B
  diff -bu A B | grep '^[+-]'

On my example machine I have approximatly 10KB of route output.  There we
see the very first non-title element is lost in the while read case,
and an entry around the 8K mark in the cat case:

  +wlan0 00000000 02021EAC 0003 0 0 400 00000000 0 0 0
  -tun1  00C0AC0A 00000000 0001 0 0 950 00C0FFFF 0 0 0

Fix up the off-by-one when reaquiring position on continuation.

Fixes: 8be33e955c ("fib_trie: Fib walk rcu should take a tnode and key instead of a trie and a leaf")
BugLink: http://bugs.launchpad.net/bugs/1483440
Acked-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 21:16:29 -07:00
Linus Lüssing a516993f0a net: fix wrong skb_get() usage / crash in IGMP/MLD parsing code
The recent refactoring of the IGMP and MLD parsing code into
ipv6_mc_check_mld() / ip_mc_check_igmp() introduced a potential crash /
BUG() invocation for bridges:

I wrongly assumed that skb_get() could be used as a simple reference
counter for an skb which is not the case. skb_get() bears additional
semantics, a user count. This leads to a BUG() invocation in
pskb_expand_head() / kernel panic if pskb_may_pull() is called on an skb
with a user count greater than one - unfortunately the refactoring did
just that.

Fixing this by removing the skb_get() call and changing the API: The
caller of ipv6_mc_check_mld() / ip_mc_check_igmp() now needs to
additionally check whether the returned skb_trimmed is a clone.

Fixes: 9afd85c9e4 ("net: Export IGMP/MLD message validation code")
Reported-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 17:08:39 -07:00
Yuchung Cheng b340b26454 tcp: TLP retransmits last if failed to send new packet
When TLP fails to send new packet because of receive window
limit, it should fall back to retransmit the last packet instead.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 16:52:20 -07:00
Yuchung Cheng fcd16c0a95 tcp: don't extend RTO on failed loss probe attempts
If TLP was unable to send a probe, it extended the RTO to
now + icsk_rto. But extending the RTO makes little sense
if no TLP probe went out. With this commit, instead of
extending the RTO we re-arm it relative to the transmit time
of the write queue head.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 16:52:19 -07:00
David S. Miller 182ad468e7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/cavium/Kconfig

The cavium conflict was overlapping dependency
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 16:23:11 -07:00
Mugunthan V N 76550786c6 net: ipv4: increase dhcp inter device timeout
When a system has multiple ethernet devices and during DHCP
request (for using NFS), the system waits only for HZ/2 which is
500mS before switching to another interface for DHCP.

There are some routers (Ex: Trendnet routers) which responds to
DHCP request at about 560mS. When the system has only one
ethernet interface there is no issue as the timeout is 2S and the
dev xid doesn't changes and only retries.

But when the system has multiple Ethernet like DRA74x with CPSW
in dual EMAC mode, the DHCP response is dropped as the dev xid
changes while shifting to the next device. So changing inter
device timeout to HZ (which is 1S).

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-12 16:40:22 -07:00
David Ahern 42a7b32b73 xfrm: Add oif to dst lookups
Rules can be installed that direct route lookups to specific tables based
on oif. Plumb the oif through the xfrm lookups so it gets set in the flow
struct and passed to the resolver routines.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2015-08-11 12:41:35 +02:00
Daniel Borkmann 308ac9143e netfilter: nf_conntrack: push zone object into functions
This patch replaces the zone id which is pushed down into functions
with the actual zone object. It's a bigger one-time change, but
needed for later on extending zones with a direction parameter, and
thus decoupling this additional information from all call-sites.

No functional changes in this patch.

The default zone becomes a global const object, namely nf_ct_zone_dflt
and will be returned directly in various cases, one being, when there's
f.e. no zoning support.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-11 12:29:01 +02:00
Eric Dumazet 3257d8b12f inet: fix possible request socket leak
In commit b357a364c5 ("inet: fix possible panic in
reqsk_queue_unlink()"), I missed fact that tcp_check_req()
can return the listener socket in one case, and that we must
release the request socket refcount or we leak it.

Tested:

 Following packetdrill test template shows the issue

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    < S 0:0(0) win 2920 <mss 1460,sackOK,nop,nop>
+0    > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK>
+.002 < . 1:1(0) ack 21 win 2920
+0    > R 21:21(0)

Fixes: b357a364c5 ("inet: fix possible panic in reqsk_queue_unlink()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 21:17:45 -07:00
Eric Dumazet 2235f2ac75 inet: fix races with reqsk timers
reqsk_queue_destroy() and reqsk_queue_unlink() should use
del_timer_sync() instead of del_timer() before calling reqsk_put(),
otherwise we could free a req still used by another cpu.

But before doing so, reqsk_queue_destroy() must release syn_wait_lock
spinlock or risk a dead lock, as reqsk_timer_handler() might
need to take this same spinlock from reqsk_queue_unlink() (called from
inet_csk_reqsk_queue_drop())

Fixes: fa76ce7328 ("inet: get rid of central tcp/dccp listener timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 21:17:29 -07:00
David S. Miller 182554570a Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contains five Netfilter fixes for your net tree,
they are:

1) Silence a warning on falling back to vmalloc(). Since 88eab472ec, we can
   easily hit this warning message, that gets users confused. So let's get rid
   of it.

2) Recently when porting the template object allocation on top of kmalloc to
   fix the netns dependencies between x_tables and conntrack, the error
   checks where left unchanged. Remove IS_ERR() and check for NULL instead.
   Patch from Dan Carpenter.

3) Don't ignore gfp_flags in the new nf_ct_tmpl_alloc() function, from
   Joe Stringer.

4) Fix a crash due to NULL pointer dereference in ip6t_SYNPROXY, patch from
   Phil Sutter.

5) The sequence number of the Syn+ack that is sent from SYNPROXY to clients is
   not adjusted through our NAT infrastructure, as a result the client may
   ignore this TCP packet and TCP flow hangs until the client probes us.  Also
   from Phil Sutter.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 21:03:25 -07:00
Pravin B Shelar 9f57c67c37 gre: Remove support for sharing GRE protocol hook.
Support for sharing GREPROTO_CISCO port was added so that
OVS gre port and kernel GRE devices can co-exist. After
flow-based tunneling patches OVS GRE protocol processing
is completely moved to ip_gre module. so there is no need
for GRE protocol hook. Following patch consolidates
GRE protocol related functions into ip_gre module.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 14:03:54 -07:00
Pravin B Shelar b2acd1dc39 openvswitch: Use regular GRE net_device instead of vport
Using GRE tunnel meta data collection feature, we can implement
OVS GRE vport. This patch removes all of the OVS
specific GRE code and make OVS use a ip_gre net_device.
Minimal GRE vport is kept to handle compatibility with
current userspace application.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 14:03:54 -07:00
Pravin B Shelar 2e15ea390e ip_gre: Add support to collect tunnel metadata.
Following patch create new tunnel flag which enable
tunnel metadata collection on given device.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 14:03:54 -07:00
Phil Sutter 3c16241c44 netfilter: SYNPROXY: fix sending window update to client
Upon receipt of SYNACK from the server, ipt_SYNPROXY first sends back an ACK to
finish the server handshake, then calls nf_ct_seqadj_init() to initiate
sequence number adjustment of forwarded packets to the client and finally sends
a window update to the client to unblock it's TX queue.

Since synproxy_send_client_ack() does not set synproxy_send_tcp()'s nfct
parameter, no sequence number adjustment happens and the client receives the
window update with incorrect sequence number. Depending on client TCP
implementation, this leads to a significant delay (until a window probe is
being sent).

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-10 13:55:07 +02:00
Pablo Neira Ayuso d877f07112 netfilter: nf_tables: add nft_dup expression
This new expression uses the nf_dup engine to clone packets to a given gateway.
Unlike xt_TEE, we use an index to indicate output interface which should be
fine at this stage.

Moreover, change to the preemtion-safe this_cpu_read(nf_skb_duplicated) from
nf_dup_ipv{4,6} to silence a lockdep splat.

Based on the original tee expression from Arturo Borrero Gonzalez, although
this patch has diverted quite a bit from this initial effort due to the
change to support maps.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-07 11:49:49 +02:00
Pablo Neira Ayuso bbde9fc182 netfilter: factor out packet duplication for IPv4/IPv6
Extracted from the xtables TEE target. This creates two new modules for IPv4
and IPv6 that are shared between the TEE target and the new nf_tables dup
expressions.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-07 11:49:49 +02:00
David S. Miller 9dc20a6496 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next, they are:

1) A couple of cleanups for the netfilter core hook from Eric Biederman.

2) Net namespace hook registration, also from Eric. This adds a dependency with
   the rtnl_lock. This should be fine by now but we have to keep an eye on this
   because if we ever get the per-subsys nfnl_lock before rtnl we have may
   problems in the future. But we have room to remove this in the future by
   propagating the complexity to the clients, by registering hooks for the init
   netns functions.

3) Update nf_tables to use the new net namespace hook infrastructure, also from
   Eric.

4) Three patches to refine and to address problems from the new net namespace
   hook infrastructure.

5) Switch to alternate jumpstack in xtables iff the packet is reentering. This
   only applies to a very special case, the TEE target, but Eric Dumazet
   reports that this is slowing down things for everyone else. So let's only
   switch to the alternate jumpstack if the tee target is in used through a
   static key. This batch also comes with offline precalculation of the
   jumpstack based on the callchain depth. From Florian Westphal.

6) Minimal SCTP multihoming support for our conntrack helper, from Michal
   Kubecek.

7) Reduce nf_bridge_info per skbuff scratchpad area to 32 bytes, from Florian
   Westphal.

8) Fix several checkpatch errors in bridge netfilter, from Bernhard Thaler.

9) Get rid of useless debug message in ip6t_REJECT, from Subash Abhinov.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-04 23:57:45 -07:00
Robert Shearman 0335f5b500 ipv4: apply lwtunnel encap for locally-generated packets
lwtunnel encap is applied for forwarded packets, but not for
locally-generated packets. This is because the output function is not
overridden in __mkroute_output, unlike it is in __mkroute_input.

The lwtunnel state is correctly set on the rth through the call to
rt_set_nexthop, so all that needs to be done is to override the dst
output function to be lwtunnel_output if there is lwtunnel state
present and it requires output redirection.

Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:26:14 -07:00
Eric Dumazet 10e2eb878f udp: fix dst races with multicast early demux
Multicast dst are not cached. They carry DST_NOCACHE.

As mentioned in commit f886497212 ("ipv4: fix dst race in
sk_dst_get()"), these dst need special care before caching them
into a socket.

Caching them is allowed only if their refcnt was not 0, ie we
must use atomic_inc_not_zero()

Also, we must use READ_ONCE() to fetch sk->sk_rx_dst, as mentioned
in commit d0c294c53a ("tcp: prevent fetching dst twice in early demux
code")

Fixes: 421b3885bf ("udp: ipv4: Add udp early demux")
Tested-by: Gregory Hoggarth <Gregory.Hoggarth@alliedtelesis.co.nz>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Gregory Hoggarth <Gregory.Hoggarth@alliedtelesis.co.nz>
Reported-by: Alex Gartrell <agartrell@fb.com>
Cc: Michal Kubeček <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:16:50 -07:00
David S. Miller 5510b3c2a1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	arch/s390/net/bpf_jit_comp.c
	drivers/net/ethernet/ti/netcp_ethss.c
	net/bridge/br_multicast.c
	net/ipv4/ip_fragment.c

All four conflicts were cases of simple overlapping
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 23:52:20 -07:00
Florian Westphal 72b1e5e4ca netfilter: bridge: reduce nf_bridge_info to 32 bytes again
We can use union for most of the temporary cruft (original ipv4/ipv6
address, source mac, physoutdev) since they're used during different
stages of br netfilter traversal.

Also get rid of the last two ->mask users.

Shrinks struct from 48 to 32 on 64bit arch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-30 13:37:42 +02:00
Tom Herbert 877d1f6291 net: Set sk_txhash from a random number
This patch creates sk_set_txhash and eliminates protocol specific
inet_set_txhash and ip6_set_txhash. sk_set_txhash simply sets a
random number instead of performing flow dissection. sk_set_txash
is also allowed to be called multiple times for the same socket,
we'll need this when redoing the hash for negative routing advice.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 22:44:04 -07:00
Eric Dumazet 11c91ef98f arp: filter NOARP neighbours for SIOCGARP
When arp is off on a device, and ioctl(SIOCGARP) is queried,
a buggy answer is given with MAC address of the device, instead
of the mac address of the destination/gateway.

We filter out NUD_NOARP neighbours for /proc/net/arp,
we must do the same for SIOCGARP ioctl.

Tested:

lpaa23:~# ./arp 10.246.7.190
MAC=00:01:e8:22:cb:1d      // correct answer

lpaa23:~# ip link set dev eth0 arp off
lpaa23:~# cat /proc/net/arp   # check arp table is now 'empty'
IP address       HW type     Flags       HW address    Mask     Device
lpaa23:~# ./arp 10.246.7.190
MAC=00:1a:11:c3:0d:7f   // buggy answer before patch (this is eth0 mac)

After patch :

lpaa23:~# ip link set dev eth0 arp off
lpaa23:~# ./arp 10.246.7.190
ioctl(SIOCGARP) failed: No such device or address

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Vytautas Valancius <valas@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-28 23:41:24 -07:00
David Ward 865b804244 net/ipv4: suppress NETDEV_UP notification on address lifetime update
This notification causes the FIB to be updated, which is not needed
because the address already exists, and more importantly it may undo
intentional changes that were made to the FIB after the address was
originally added. (As a point of comparison, when an address becomes
deprecated because its preferred lifetime expired, a notification on
this chain is not generated.)

The motivation for this commit is fixing an incompatibility between
DHCP clients which set and update the address lifetime according to
the lease, and a commercial VPN client which replaces kernel routes
in a way that outbound traffic is sent only through the tunnel (and
disconnects if any further route changes are detected via netlink).

Signed-off-by: David Ward <david.ward@ll.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-28 23:38:13 -07:00
Alexander Duyck 1513069edc fib_trie: Drop unnecessary calls to leaf_pull_suffix
It was reported that update_suffix was taking a long time on systems where
a large number of leaves were attached to a single node.  As it turns out
fib_table_flush was calling update_suffix for each leaf that didn't have all
of the aliases stripped from it.  As a result, on this large node removing
one leaf would result in us calling update_suffix for every other leaf on
the node.

The fix is to just remove the calls to leaf_pull_suffix since they are
redundant as we already have a call in resize that will go through and
update the suffix length for the node before we exit out of
fib_table_flush or fib_table_flush_external.

Reported-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 14:29:11 -07:00
Eric Dumazet 99d7662a04 tcp: tso: allow deferring under reordering state
While doing experiments with reordering resilience, we found
linux senders were not able to send at full speed under reordering,
because every incoming SACK was releasing one MSS.

This patch removes the limitation, as we did for CWR state
in commit a0ea700e40 ("tcp: tso: allow CA_CWR state in
tcp_tso_should_defer()")

Neal Cardwell had a concern about limited transmit so
Yuchung conducted experiments on GFE and found nothing
worth adding an extra check on fast path :

  if (icsk->icsk_ca_state == TCP_CA_Disorder &&
      tcp_sk(sk)->reordering == sysctl_tcp_reordering)
          goto send_now;

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 01:23:20 -07:00
Sabrina Dubroca dfbafc9953 tcp: fix recv with flags MSG_WAITALL | MSG_PEEK
Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called
with flags = MSG_WAITALL | MSG_PEEK.

sk_wait_data waits for sk_receive_queue not empty, but in this case,
the receive queue is not empty, but does not contain any skb that we
can use.

Add a "last skb seen on receive queue" argument to sk_wait_data, so
that it sleeps until the receive queue has new skbs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258
Reported-by: Enrico Scholz <rh-bugzilla@ensc.de>
Reported-by: Dan Searle <dan@censornet.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 01:06:53 -07:00
Nicolas Dichtel 5a6228a0b4 lwtunnel: change prototype of lwtunnel_state_get()
It saves some lines and simplify a bit the code when the state is returning
by this function. It's also useful to handle a NULL entry.

To avoid too long lines, I've also renamed lwtunnel_state_get() and
lwtunnel_state_put() to lwtstate_get() and lwtstate_put().

CC: Thomas Graf <tgraf@suug.ch>
CC: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 01:02:49 -07:00
Nikolay Aleksandrov caaecdd3d3 inet: frags: remove INET_FRAG_EVICTED and use list_evictor for the test
We can simply remove the INET_FRAG_EVICTED flag to avoid all the flags
race conditions with the evictor and use a participation test for the
evictor list, when we're at that point (after inet_frag_kill) in the
timer there're 2 possible cases:

1. The evictor added the entry to its evictor list while the timer was
waiting for the chainlock
or
2. The timer unchained the entry and the evictor won't see it

In both cases we should be able to see list_evictor correctly due
to the sync on the chainlock.

Joint work with Florian Westphal.

Tested-by: Frank Schreuder <fschreuder@transip.nl>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26 21:00:15 -07:00
Florian Westphal 5719b296fb inet: frag: don't wait for timer deletion when evicting
Frank reports 'NMI watchdog: BUG: soft lockup' errors when
load is high.  Instead of (potentially) unbounded restarts of the
eviction process, just skip to the next entry.

One caveat is that, when a netns is exiting, a timer may still be running
by the time inet_evict_bucket returns.

We use the frag memory accounting to wait for outstanding timers,
so that when we free the percpu counter we can be sure no running
timer will trip over it.

Reported-and-tested-by: Frank Schreuder <fschreuder@transip.nl>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26 21:00:14 -07:00
Florian Westphal 0e60d245a0 inet: frag: change *_frag_mem_limit functions to take netns_frags as argument
Followup patch will call it after inet_frag_queue was freed, so q->net
doesn't work anymore (but netf = q->net; free(q); mem_limit(netf) would).

Tested-by: Frank Schreuder <fschreuder@transip.nl>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26 21:00:14 -07:00
Florian Westphal d1fe19444d inet: frag: don't re-use chainlist for evictor
commit 65ba1f1ec0 ("inet: frags: fix a race between inet_evict_bucket
and inet_frag_kill") describes the bug, but the fix doesn't work reliably.

Problem is that ->flags member can be set on other cpu without chainlock
being held by that task, i.e. the RMW-Cycle can clear INET_FRAG_EVICTED
bit after we put the element on the evictor private list.

We can crash when walking the 'private' evictor list since an element can
be deleted from list underneath the evictor.

Join work with Nikolay Alexandrov.

Fixes: b13d3cbfb8 ("inet: frag: move eviction of queues to work queue")
Reported-by: Johan Schuijt <johan@transip.nl>
Tested-by: Frank Schreuder <fschreuder@transip.nl>
Signed-off-by: Nikolay Alexandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26 21:00:14 -07:00
Julian Anastasov 88f6432036 ipv4: be more aggressive when probing alternative gateways
Currently, we do not notice if new alternative gateways
are added. We can do it by checking for present neigh
entry. Also, gateways that are currently probed (NUD_INCOMPLETE)
can be skipped from round-robin probing.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26 20:56:27 -07:00
Julian Anastasov 2392debc2b ipv4: consider TOS in fib_select_default
fib_select_default considers alternative routes only when
res->fi is for the first alias in res->fa_head. In the
common case this can happen only when the initial lookup
matches the first alias with highest TOS value. This
prevents the alternative routes to require specific TOS.

This patch solves the problem as follows:

- routes that require specific TOS should be returned by
fib_select_default only when TOS matches, as already done
in fib_table_lookup. This rule implies that depending on the
TOS we can have many different lists of alternative gateways
and we have to keep the last used gateway (fa_default) in first
alias for the TOS instead of using single tb_default value.

- as the aliases are ordered by many keys (TOS desc,
fib_priority asc), we restrict the possible results to
routes with matching TOS and lowest metric (fib_priority)
and routes that match any TOS, again with lowest metric.

For example, packet with TOS 8 can not use gw3 (not lowest
metric), gw4 (different TOS) and gw6 (not lowest metric),
all other gateways can be used:

tos 8 via gw1 metric 2 <--- res->fa_head and res->fi
tos 8 via gw2 metric 2
tos 8 via gw3 metric 3
tos 4 via gw4
tos 0 via gw5
tos 0 via gw6 metric 1

Reported-by: Hagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-24 22:46:11 -07:00
Julian Anastasov 18a912e9a8 ipv4: fib_select_default should match the prefix
fib_trie starting from 4.1 can link fib aliases from
different prefixes in same list. Make sure the alternative
gateways are in same table and for same prefix (0) by
checking tb_id and fa_slen.

Fixes: 79e5ad2ceb ("fib_trie: Remove leaf_info")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-24 22:46:09 -07:00
Thomas Graf 045a0fa0c5 ip_tunnel: Call ip_tunnel_core_init() from inet_init()
Convert the module_init() to a invocation from inet_init() since
ip_tunnel_core is part of the INET built-in.

Fixes: 3093fbe7ff ("route: Per route IP tunnel metadata via lightweight tunnel")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-23 01:28:21 -07:00
David S. Miller c5e40ee287 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/bridge/br_mdb.c

br_mdb.c conflict was a function call being removed to fix a bug in
'net' but whose signature was changed in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-23 00:41:16 -07:00
Rick Jones b56ea2985d net: track success and failure of TCP PMTU probing
Track success and failure of TCP PMTU probing.

Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 22:36:33 -07:00
Eric Dumazet 89e478a2aa tcp: suppress a division by zero warning
Andrew Morton reported following warning on one ARM build
with gcc-4.4 :

net/ipv4/inet_hashtables.c: In function 'inet_ehash_locks_alloc':
net/ipv4/inet_hashtables.c:617: warning: division by zero

Even guarded with a test on sizeof(spinlock_t), compiler does not
like current construct on a !CONFIG_SMP build.

Remove the warning by using a temporary variable.

Fixes: 095dc8e0c3 ("tcp: fix/cleanup inet_ehash_locks_alloc()")
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 22:13:13 -07:00
Thomas Graf e7030878fc fib: Add fib rule match on tunnel id
This add the ability to select a routing table based on the tunnel
id which allows to maintain separate routing tables for each virtual
tunnel network.

ip rule add from all tunnel-id 100 lookup 100
ip rule add from all tunnel-id 200 lookup 200

A new static key controls the collection of metadata at tunnel level
upon demand.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:06 -07:00
Thomas Graf 3093fbe7ff route: Per route IP tunnel metadata via lightweight tunnel
This introduces a new IP tunnel lightweight tunnel type which allows
to specify IP tunnel instructions per route. Only IPv4 is supported
at this point.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:06 -07:00
Thomas Graf 1b7179d3ad route: Extend flow representation with tunnel key
Add a new flowi_tunnel structure which is a subset of ip_tunnel_key to
allow routes to match on tunnel metadata. For now, the tunnel id is
added to flowi_tunnel which allows for routes to be bound to specific
virtual tunnels.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:06 -07:00
Thomas Graf 0accfc268f arp: Inherit metadata dst when creating ARP requests
If output device wants to see the dst, inherit the dst of the
original skb and pass it on to generate the ARP request.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:05 -07:00
Thomas Graf f38a9eb1f7 dst: Metadata destinations
Introduces a new dst_metadata which enables to carry per packet metadata
between forwarding and processing elements via the skb->dst pointer.

The structure is set up to be a union. Thus, each separate type of
metadata requires its own dst instance. If demand arises to carry
multiple types of metadata concurrently, metadata dst entries can be
made stackable.

The metadata dst entry is refcnt'ed as expected for now but a non
reference counted use is possible if the reference is forced before
queueing the skb.

In order to allow allocating dsts with variable length, the existing
dst_alloc() is split into a dst_alloc() and dst_init() function. The
existing dst_init() function to initialize the subsystem is being
renamed to dst_subsys_init() to make it clear what is what.

The check before ip_route_input() is changed to ignore metadata dsts
and drop the dst inside the routing function thus allowing to interpret
metadata in a later commit.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:05 -07:00
Thomas Graf 773a69d64b icmp: Don't leak original dst into ip_route_input()
ip_route_input() unconditionally overwrites the dst. Hide the original
dst attached to the skb by calling skb_dst_set(skb, NULL) prior to
ip_route_input().

Reported-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:05 -07:00
Roopa Prabhu 8602a62502 ipv4: redirect dst output to lwtunnel output
For input routes with tunnel encap state this patch redirects
dst output functions to lwtunnel_output which later resolves to
the corresponding lwtunnel output function.

This has been tested to work with mpls ip tunnels.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:04 -07:00
Roopa Prabhu 571e722676 ipv4: support for fib route lwtunnel encap attributes
This patch adds support in ipv4 fib functions to parse user
provided encap attributes and attach encap state data to fib_nh
and rtable.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:03 -07:00
Edward Hyunkoo Jee 0848f6428b inet: frags: fix defragmented packet's IP header for af_packet
When ip_frag_queue() computes positions, it assumes that the passed
sk_buff does not contain L2 headers.

However, when PACKET_FANOUT_FLAG_DEFRAG is used, IP reassembly
functions can be called on outgoing packets that contain L2 headers.

Also, IPv4 checksum is not corrected after reassembly.

Fixes: 7736d33f42 ("packet: Add pre-defragmentation support for ipv4 fanouts.")
Signed-off-by: Edward Hyunkoo Jee <edjee@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jerry Chu <hkchu@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:29:23 -07:00
Eric Dumazet 03645a11a5 ipv6: lock socket in ip6_datagram_connect()
ip6_datagram_connect() is doing a lot of socket changes without
socket being locked.

This looks wrong, at least for udp_lib_rehash() which could corrupt
lists because of concurrent udp_sk(sk)->udp_portaddr_hash accesses.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 17:25:51 -07:00
Yuchung Cheng f82b681a51 tcp: don't use F-RTO on non-recurring timeouts
Currently F-RTO may repeatedly send new data packets on non-recurring
timeouts in CA_Loss mode. This is a bug because F-RTO (RFC5682)
should only be used on either new recovery or recurring timeouts.

This exacerbates the recovery progress during frequent timeout &
repair, because we prioritize sending new data packets instead of
repairing the holes when the bandwidth is already scarce.

Fix it by correcting the test of a new recovery episode.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 17:17:21 -07:00
Florian Westphal 6c7941dee9 netfilter: xtables: remove __pure annotation
sparse complains:
ip_tables.c:361:27: warning: incorrect type in assignment (different modifiers)
ip_tables.c:361:27:    expected struct ipt_entry *[assigned] e
ip_tables.c:361:27:    got struct ipt_entry [pure] *

doesn't change generated code.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15 18:18:07 +02:00
Florian Westphal dcebd3153e netfilter: add and use jump label for xt_tee
Don't bother testing if we need to switch to alternate stack
unless TEE target is used.

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15 18:18:06 +02:00
Florian Westphal 7814b6ec6d netfilter: xtables: don't save/restore jumpstack offset
In most cases there is no reentrancy into ip/ip6tables.

For skbs sent by REJECT or SYNPROXY targets, there is one level
of reentrancy, but its not relevant as those targets issue an absolute
verdict, i.e. the jumpstack can be clobbered since its not used
after the target issues absolute verdict (ACCEPT, DROP, STOLEN, etc).

So the only special case where it is relevant is the TEE target, which
returns XT_CONTINUE.

This patch changes ip(6)_do_table to always use the jump stack starting
from 0.

When we detect we're operating on an skb sent via TEE (percpu
nf_skb_duplicated is 1) we switch to an alternate stack to leave
the original one alone.

Since there is no TEE support for arptables, it doesn't need to
test if tee is active.

The jump stack overflow tests are no longer needed as well --
since ->stacksize is the largest call depth we cannot exceed it.

A much better alternative to the external jumpstack would be to just
declare a jumps[32] stack on the local stack frame, but that would mean
we'd have to reject iptables rulesets that used to work before.

Another alternative would be to start rejecting rulesets with a larger
call depth, e.g. 1000 -- in this case it would be feasible to allocate the
entire stack in the percpu area which would avoid one dereference.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15 18:18:06 +02:00
Florian Westphal 98d1bd802c netfilter: xtables: compute exact size needed for jumpstack
The {arp,ip,ip6tables} jump stack is currently sized based
on the number of user chains.

However, its rather unlikely that every user defined chain jumps to the
next, so lets use the existing loop detection logic to also track the
chain depths.

The stacksize is then set to the largest chain depth seen.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15 18:18:04 +02:00
David S. Miller 638d3c6381 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/bridge/br_mdb.c

Minor conflict in br_mdb.c, in 'net' we added a memset of the
on-stack 'ip' variable whereas in 'net-next' we assign a new
member 'vid'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-13 17:28:09 -07:00
Florian Westphal 14fe22e334 Revert "ipv4: use skb coalescing in defragmentation"
This reverts commit 3cc4949269.

There is nothing wrong with coalescing during defragmentation, it
reduces truesize overhead and simplifies things for the receiving
socket (no fraglist walk needed).

However, it also destroys geometry of the original fragments.
While that doesn't cause any breakage (we make sure to not exceed largest
original size) ip_do_fragment contains a 'fastpath' that takes advantage
of a present frag list and results in fragments that (in most cases)
match what was received.

In case its needed the coalescing could be done later, when we're sure
the skb is not forwarded.  But discussion during NFWS resulted in
'lets just remove this for now'.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-11 21:16:40 -07:00
Phil Sutter 8220ea2324 net: inet_diag: always export IPV6_V6ONLY sockopt for listening sockets
Reconsidering my commit 20462155 "net: inet_diag: export IPV6_V6ONLY
sockopt", I am not happy with the limitations it causes for socket
analysing code in userspace. Exporting the value only if it is set makes
it hard for userspace to decide whether the option is not set or the
kernel does not support exporting the option at all.

>From an auditor's perspective, the interesting question for listening
AF_INET6 sockets is: "Does it NOT have IPV6_V6ONLY set?" Because it is
the unexpected case. This patch allows to answer this question reliably.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-10 23:25:24 -07:00
Eric Dumazet a4e2405cc5 tcp: do not export tcp_init_xmit_timers()
After commit 900f65d361 ("tcp: move duplicate code from
tcp_v4_init_sock()/tcp_v6_init_sock()"), we no longer
need to export tcp_init_xmit_timers()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 21:44:38 -07:00
Masatake YAMATO cb1c61680d route: remove unsed variable in __mkroute_input
flags local variable in __mkroute_input is not used as a variable.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 21:34:34 -07:00
Tom Herbert 35a256fee5 ipv6: Nonlocal bind
Add support to allow non-local binds similar to how this was done for IPv4.
Non-local binds are very useful in emulating the Internet in a box, etc.

This add the ip_nonlocal_bind sysctl under ipv6.

Testing:

Set up nonlocal binding and receive routing on a host, e.g.:

ip -6 rule add from ::/0 iif eth0 lookup 200
ip -6 route add local 2001:0:0:1::/64 dev lo proto kernel scope host table 200
sysctl -w net.ipv6.ip_nonlocal_bind=1

Set up routing to 2001:0:0:1::/64 on peer to go to first host

ping6 -I 2001:0:0:1::1 peer-address -- to verify

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 21:09:10 -07:00
Eric Dumazet dbe7faa404 inet: inet_twsk_deschedule factorization
inet_twsk_deschedule() calls are followed by inet_twsk_put().

Only particular case is in inet_twsk_purge() but there is no point
to defer the inet_twsk_put() after re-enabling BH.

Lets rename inet_twsk_deschedule() to inet_twsk_deschedule_put()
and move the inet_twsk_put() inside.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 15:12:20 -07:00
Eric Dumazet fc01538f9f inet: simplify timewait refcounting
timewait sockets have a complex refcounting logic.
Once we realize it should be similar to established and
syn_recv sockets, we can use sk_nulls_del_node_init_rcu()
and remove inet_twsk_unhash()

In particular, deferred inet_twsk_put() added in commit
13475a30b6 ("tcp: connect() race with timewait reuse")
looks unecessary : When removing a timewait socket from
ehash or bhash, caller must own a reference on the socket
anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 15:12:20 -07:00
Yuchung Cheng b20a3fa30a tcp: update congestion state first before raising cwnd
The congestion state and cwnd can be updated in the wrong order.
For example, upon receiving a dubious ACK, we incorrectly raise
the cwnd first (tcp_may_raise_cwnd()/tcp_cong_avoid()) because
the state is still Open, then enter recovery state to reduce cwnd.

For another example, if the ACK indicates spurious timeout or
retransmits, we first revert the cwnd reduction and congestion
state back to Open state.  But we don't raise the cwnd even though
the ACK does not indicate any congestion.

To fix this problem we should first call tcp_fastretrans_alert() to
process the dubious ACK and update the congestion state, then call
tcp_may_raise_cwnd() that raises cwnd based on the current state.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 14:22:52 -07:00
Yuchung Cheng 76174004a0 tcp: do not slow start when cwnd equals ssthresh
In the original design slow start is only used to raise cwnd
when cwnd is stricly below ssthresh. It makes little sense
to slow start when cwnd == ssthresh: especially
when hystart has set ssthresh in the initial ramp, or after
recovery when cwnd resets to ssthresh. Not doing so will
also help reduce the buffer bloat slightly.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 14:22:52 -07:00
Yuchung Cheng 071d5080e3 tcp: add tcp_in_slow_start helper
Add a helper to test the slow start condition in various congestion
control modules and other places. This is to prepare a slight improvement
in policy as to exactly when to slow start.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 14:22:52 -07:00
Jon Maxwell 2251ae46af tcp: v1 always send a quick ack when quickacks are enabled
V1 of this patch contains Eric Dumazet's suggestion to move the per
dst RTAX_QUICKACK check into tcp_in_quickack_mode(). Thanks Eric.

I ran some tests and after setting the "ip route change quickack 1"
knob there were still many delayed ACKs sent. This occured
because when icsk_ack.quick=0 the !icsk_ack.pingpong value is
subsequently ignored as tcp_in_quickack_mode() checks both these
values. The condition for a quick ack to trigger requires
that both icsk_ack.quick != 0 and icsk_ack.pingpong=0. Currently
only icsk_ack.pingpong is controlled by the knob. But the
icsk_ack.quick value changes dynamically depending on heuristics.
The crux of the matter is that delayed acks still cannot be entirely
disabled even with the RTAX_QUICKACK per dst knob enabled. This
patch ensures that a quick ack is always sent when the RTAX_QUICKACK
per dst knob is turned on.

The "ip route change quickack 1" knob was recently added to enable
quickacks. It was modeled around the TCP_QUICKACK setsockopt() option.
This issue is that even with "ip route change quickack 1" enabled
we still see delayed ACKs under some conditions. It would be nice
to be able to completely disable delayed ACKs.

Here is an example:

# netstat -s|grep dela
    3 delayed acks sent

For all routes enable the knob

# ip route change quickack 1

Generate some traffic across a slow link and we still see the delayed
acks.

# netstat -s|grep dela
    106 delayed acks sent
    1 delayed acks further delayed because of locked socket

The issue is that both the "ip route change quickack 1" knob and
the TCP_QUICKACK option set the icsk_ack.pingpong variable to 0.
However at the business end in the __tcp_ack_snd_check() routine,
tcp_in_quickack_mode() checks that both icsk_ack.quick != 0
and icsk_ack.pingpong=0 in order to trigger a quickack. As
icsk_ack.quick is determined by heuristics it can be 0. When
that occurs the icsk_ack.pingpong value is ignored and a delayed
ACK is sent regardless.

This patch moves the RTAX_QUICKACK per dst check into the
tcp_in_quickack_mode() routine which ensures that a quickack is
always sent when the quickack knob is enabled for that dst.

Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 14:15:44 -07:00
David S. Miller ace15bbb39 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contains Netfilter fixes for your net tree. This batch
mostly comes with patches to address fallout from the previous merge window
cycle, they are:

1) Use entry->state.hook_list from nf_queue() instead of the global nf_hooks
   which is not valid when used from NFPROTO_NETDEV, this should cause no
   problems though since we have no userspace queueing for that family, but
   let's fix this now for the sake of correctness. Patch from Eric W. Biederman.

2) Fix compilation breakage in bridge netfilter if CONFIG_NF_DEFRAG_IPV4 is not
   set, from Bernhard Thaler.

3) Use percpu jumpstack in arptables too, now that there's a single copy of the
   rule blob we can't store the return address there anymore. Patch from
   Florian Westphal.

4) Fix a skb leak in the xmit path of bridge netfilter, problem there since
   2.6.37 although it should be not possible to hit invalid traffic there, also
   from Florian.

5) Eric Leblond reports that when loading a large ruleset with many missing
   modules after a fresh boot, nf_tables can take long time commit it. Fix this
   by processing the full batch until the end, even on missing modules, then
   abort only once and restart processing.

6) Add bridge netfilter files to the MAINTAINER files.

7) Fix a net_device refcount leak in the new IPV6 bridge netfilter code, from
   Julien Grall.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 00:03:10 -07:00
Andy Gospodarek 974d7af5fc ipv4: add support for linkdown sysctl to netconf
This kernel patch exports the value of the new
ignore_routes_with_linkdown via netconf.

v2: changes to notify userspace via netlink when sysctl values change
and proposed for 'net' since this could be considered a bugfix

Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Suggested-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-08 23:34:53 -07:00
Timo Teräs fc24f2b209 ip_tunnel: fix ipv4 pmtu check to honor inner ip header df
Frag needed should be sent only if the inner header asked
to not fragment. Currently fragmentation is broken if the
tunnel has df set, but df was not asked in the original
packet. The tunnel's df needs to be still checked to update
internally the pmtu cache.

Commit 23a3647bc4 broke it, and this commit fixes
the ipv4 df check back to the way it was.

Fixes: 23a3647bc4 ("ip_tunnels: Use skb-len to PMTU check.")
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-08 16:03:09 -07:00
Yuchung Cheng 3759824da8 tcp: PRR uses CRB mode by default and SS mode conditionally
PRR slow start is often too aggressive especially when drops are
caused by traffic policers. The policers mainly use token bucket
to enforce the rate so sending (twice) faster than the delivery
rate causes excessive drops.

This patch changes PRR to the conservative reduction bound
(CRB) mode in RFC 6937 by default. CRB follows the packet
conservation rule to send at most the delivery rate by default.

But if many packets are lost and the pipe is empty, CRB may take N
round trips to repair N losses. We conditionally turn on slow start
mode if all these conditions are made to speed up the recovery:

  1) on the second round or later in recovery
  2) retransmission sent in the previous round is delivered on this ACK
  3) no retransmission is marked lost on this ACK

By using packet conservation by default, this change reduces the loss
retransmits signicantly on networks that deploy traffic policers,
up to 20% reduction of overall loss rate.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-08 13:29:46 -07:00
Yuchung Cheng 291a00d1a7 tcp: reduce cwnd if retransmit is lost in CA_Loss
If the retransmission in CA_Loss is lost again, we should not
continue to slow start or raise cwnd in congestion avoidance mode.
Instead we should enter fast recovery and use PRR to reduce cwnd,
following the principle in RFC5681:

"... or the loss of a retransmission, should be taken as two
 indications of congestion and, therefore, cwnd (and ssthresh) MUST
 be lowered twice in this case."

This is especially important to reduce loss when the CA_Loss
state was caused by a traffic policer dropping the entire inflight.
The CA_Loss state has a problem where a loss of L packets causes the
sender to send a burst of L packets. So a policer that's dropping
most packets in a given RTT can cause a huge retransmit storm. By
contrast, PRR includes logic to bound the number of outbound packets
that result from a given ACK. So switching to CA_Recovery on lost
retransmits in CA_Loss avoids this retransmit storm problem when
in CA_Loss.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-08 13:29:45 -07:00
Linus Torvalds 9d90f03531 Replace module_init with appropriate alternate initcall in non modules.
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Merge tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull module_init replacement part two from Paul Gortmaker:
 "Replace module_init with appropriate alternate initcall in non
  modules.

  This series converts non-modular code that is using the module_init()
  call to hook itself into the system to instead use one of our
  alternate priority initcalls.

  Unlike the previous series that used device_initcall and hence was a
  runtime no-op, these commits change to one of the alternate initcalls,
  because (a) we have them and (b) it seems like the right thing to do.

  For example, it would seem logical to use arch_initcall for arch
  specific setup code and fs_initcall for filesystem setup code.

  This does mean however, that changes in the init ordering will be
  taking place, and so there is a small risk that some kind of implicit
  init ordering issue may lie uncovered.  But I think it is still better
  to give these ones sensible priorities than to just assign them all to
  device_initcall in order to exactly preserve the old ordering.

  Thad said, we have already made similar changes in core kernel code in
  commit c96d6660dc ("kernel: audit/fix non-modular users of
  module_init in core code") without any regressions reported, so this
  type of change isn't without precedent.  It has also got the same
  local testing and linux-next coverage as all the other pull requests
  that I'm sending for this merge window have got.

  Once again, there is an unused module_exit function removal that shows
  up as an outlier upon casual inspection of the diffstat"

* tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  x86: perf_event_intel_pt.c: use arch_initcall to hook in enabling
  x86: perf_event_intel_bts.c: use arch_initcall to hook in enabling
  mm/page_owner.c: use late_initcall to hook in enabling
  lib/list_sort: use late_initcall to hook in self tests
  arm: use subsys_initcall in non-modular pl320 IPC code
  powerpc: don't use module_init for non-modular core hugetlb code
  powerpc: use subsys_initcall for Freescale Local Bus
  x86: don't use module_init for non-modular core bootflag code
  netfilter: don't use module_init/exit in core IPV4 code
  fs/notify: don't use module_init for non-modular inotify_user code
  mm: replace module_init usages with subsys_initcall in nommu.c
2015-07-02 10:36:29 -07:00
Florian Westphal 3bd229976f netfilter: arptables: use percpu jumpstack
commit 482cfc3185 ("netfilter: xtables: avoid percpu ruleset duplication")

Unlike ip and ip6tables, arp tables were never converted to use the percpu
jump stack.

It still uses the rule blob to store return address, which isn't safe
anymore since we now share this blob among all processors.

Because there is no TEE support for arptables, we don't need to cope
with reentrancy, so we can use loocal variable to hold stack offset.

Fixes: 482cfc3185 ("netfilter: xtables: avoid percpu ruleset duplication")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-02 17:58:59 +02:00
Andy Gospodarek 96ac5cc963 ipv4: fix RCU lockdep warning from linkdown changes
The following lockdep splat was seen due to the wrong context for
grabbing in_dev.

===============================
[ INFO: suspicious RCU usage. ]
4.1.0-next-20150626-dbg-00020-g54a6d91-dirty #244 Not tainted
-------------------------------
include/linux/inetdevice.h:205 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
2 locks held by ip/403:
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff81453305>] rtnl_lock+0x17/0x19
 #1:  ((inetaddr_chain).rwsem){.+.+.+}, at: [<ffffffff8105c327>] __blocking_notifier_call_chain+0x35/0x6a

stack backtrace:
CPU: 2 PID: 403 Comm: ip Not tainted 4.1.0-next-20150626-dbg-00020-g54a6d91-dirty #244
 0000000000000001 ffff8800b189b728 ffffffff8150a542 ffffffff8107a8b3
 ffff880037bbea40 ffff8800b189b758 ffffffff8107cb74 ffff8800379dbd00
 ffff8800bec85800 ffff8800bf9e13c0 00000000000000ff ffff8800b189b7d8
Call Trace:
 [<ffffffff8150a542>] dump_stack+0x4c/0x6e
 [<ffffffff8107a8b3>] ? up+0x39/0x3e
 [<ffffffff8107cb74>] lockdep_rcu_suspicious+0xf7/0x100
 [<ffffffff814b63c3>] fib_dump_info+0x227/0x3e2
 [<ffffffff814b6624>] rtmsg_fib+0xa6/0x116
 [<ffffffff814b978f>] fib_table_insert+0x316/0x355
 [<ffffffff814b362e>] fib_magic+0xb7/0xc7
 [<ffffffff814b4803>] fib_add_ifaddr+0xb1/0x13b
 [<ffffffff814b4d09>] fib_inetaddr_event+0x36/0x90
 [<ffffffff8105c086>] notifier_call_chain+0x4c/0x71
 [<ffffffff8105c340>] __blocking_notifier_call_chain+0x4e/0x6a
 [<ffffffff8105c370>] blocking_notifier_call_chain+0x14/0x16
 [<ffffffff814a7f50>] __inet_insert_ifa+0x1a5/0x1b3
 [<ffffffff814a894d>] inet_rtm_newaddr+0x350/0x35f
 [<ffffffff81457866>] rtnetlink_rcv_msg+0x17b/0x18a
 [<ffffffff8107e7c3>] ? trace_hardirqs_on+0xd/0xf
 [<ffffffff8146965f>] ? netlink_deliver_tap+0x1cb/0x1f7
 [<ffffffff814576eb>] ? rtnl_newlink+0x72a/0x72a
...

This patch resolves that splat.

Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Reported-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-28 16:47:12 -07:00
Linus Torvalds e0456717e4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add TX fast path in mac80211, from Johannes Berg.

 2) Add TSO/GRO support to ibmveth, from Thomas Falcon

 3) Move away from cached routes in ipv6, just like ipv4, from Martin
    KaFai Lau.

 4) Lots of new rhashtable tests, from Thomas Graf.

 5) Run ingress qdisc lockless, from Alexei Starovoitov.

 6) Allow servers to fetch TCP packet headers for SYN packets of new
    connections, for fingerprinting.  From Eric Dumazet.

 7) Add mode parameter to pktgen, for testing receive.  From Alexei
    Starovoitov.

 8) Cache access optimizations via simplifications of build_skb(), from
    Alexander Duyck.

 9) Move page frag allocator under mm/, also from Alexander.

10) Add xmit_more support to hv_netvsc, from KY Srinivasan.

11) Add a counter guard in case we try to perform endless reclassify
    loops in the packet scheduler.

12) Extern flow dissector to be programmable and use it in new "Flower"
    classifier.  From Jiri Pirko.

13) AF_PACKET fanout rollover fixes, performance improvements, and new
    statistics.  From Willem de Bruijn.

14) Add netdev driver for GENEVE tunnels, from John W Linville.

15) Add ingress netfilter hooks and filtering, from Pablo Neira Ayuso.

16) Fix handling of epoll edge triggers in TCP, from Eric Dumazet.

17) Add an ECN retry fallback for the initial TCP handshake, from Daniel
    Borkmann.

18) Add tail call support to BPF, from Alexei Starovoitov.

19) Add several pktgen helper scripts, from Jesper Dangaard Brouer.

20) Add zerocopy support to AF_UNIX, from Hannes Frederic Sowa.

21) Favor even port numbers for allocation to connect() requests, and
    odd port numbers for bind(0), in an effort to help avoid
    ip_local_port_range exhaustion.  From Eric Dumazet.

22) Add Cavium ThunderX driver, from Sunil Goutham.

23) Allow bpf programs to access skb_iif and dev->ifindex SKB metadata,
    from Alexei Starovoitov.

24) Add support for T6 chips in cxgb4vf driver, from Hariprasad Shenai.

25) Double TCP Small Queues default to 256K to accomodate situations
    like the XEN driver and wireless aggregation.  From Wei Liu.

26) Add more entropy inputs to flow dissector, from Tom Herbert.

27) Add CDG congestion control algorithm to TCP, from Kenneth Klette
    Jonassen.

28) Convert ipset over to RCU locking, from Jozsef Kadlecsik.

29) Track and act upon link status of ipv4 route nexthops, from Andy
    Gospodarek.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1670 commits)
  bridge: vlan: flush the dynamically learned entries on port vlan delete
  bridge: multicast: add a comment to br_port_state_selection about blocking state
  net: inet_diag: export IPV6_V6ONLY sockopt
  stmmac: troubleshoot unexpected bits in des0 & des1
  net: ipv4 sysctl option to ignore routes when nexthop link is down
  net: track link-status of ipv4 nexthops
  net: switchdev: ignore unsupported bridge flags
  net: Cavium: Fix MAC address setting in shutdown state
  drivers: net: xgene: fix for ACPI support without ACPI
  ip: report the original address of ICMP messages
  net/mlx5e: Prefetch skb data on RX
  net/mlx5e: Pop cq outside mlx5e_get_cqe
  net/mlx5e: Remove mlx5e_cq.sqrq back-pointer
  net/mlx5e: Remove extra spaces
  net/mlx5e: Avoid TX CQE generation if more xmit packets expected
  net/mlx5e: Avoid redundant dev_kfree_skb() upon NOP completion
  net/mlx5e: Remove re-assignment of wq type in mlx5e_enable_rq()
  net/mlx5e: Use skb_shinfo(skb)->gso_segs rather than counting them
  net/mlx5e: Static mapping of netdev priv resources to/from netdev TX queues
  net/mlx4_en: Use HW counters for rx/tx bytes/packets in PF device
  ...
2015-06-24 16:49:49 -07:00
David S. Miller 3a07bd6fea Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/mellanox/mlx4/main.c
	net/packet/af_packet.c

Both conflicts were cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24 02:58:51 -07:00
Phil Sutter 204621551b net: inet_diag: export IPV6_V6ONLY sockopt
For AF_INET6 sockets, the value of struct ipv6_pinfo.ipv6only is
exported to userspace. It indicates whether a socket bound to in6addr_any
listens on IPv4 as well as IPv6. Since the socket is natively IPv6, it is not
listed by e.g. 'ss -l -4'.

This patch is accompanied by an appropriate one for iproute2 to enable
the additional information in 'ss -e'.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24 02:51:39 -07:00
Andy Gospodarek 0eeb075fad net: ipv4 sysctl option to ignore routes when nexthop link is down
This feature is only enabled with the new per-interface or ipv4 global
sysctls called 'ignore_routes_with_linkdown'.

net.ipv4.conf.all.ignore_routes_with_linkdown = 0
net.ipv4.conf.default.ignore_routes_with_linkdown = 0
net.ipv4.conf.lo.ignore_routes_with_linkdown = 0
...

When the above sysctls are set, will report to userspace that a route is
dead and will no longer resolve to this nexthop when performing a fib
lookup.  This will signal to userspace that the route will not be
selected.  The signalling of a RTNH_F_DEAD is only passed to userspace
if the sysctl is enabled and link is down.  This was done as without it
the netlink listeners would have no idea whether or not a nexthop would
be selected.   The kernel only sets RTNH_F_DEAD internally if the
interface has IFF_UP cleared.

With the new sysctl set, the following behavior can be observed
(interface p8p1 is link-down):

default via 10.0.5.2 dev p9p1
10.0.5.0/24 dev p9p1  proto kernel  scope link  src 10.0.5.15
70.0.0.0/24 dev p7p1  proto kernel  scope link  src 70.0.0.1
80.0.0.0/24 dev p8p1  proto kernel  scope link  src 80.0.0.1 dead linkdown
90.0.0.0/24 via 80.0.0.2 dev p8p1  metric 1 dead linkdown
90.0.0.0/24 via 70.0.0.2 dev p7p1  metric 2
90.0.0.1 via 70.0.0.2 dev p7p1  src 70.0.0.1
    cache
local 80.0.0.1 dev lo  src 80.0.0.1
    cache <local>
80.0.0.2 via 10.0.5.2 dev p9p1  src 10.0.5.15
    cache

While the route does remain in the table (so it can be modified if
needed rather than being wiped away as it would be if IFF_UP was
cleared), the proper next-hop is chosen automatically when the link is
down.  Now interface p8p1 is linked-up:

default via 10.0.5.2 dev p9p1
10.0.5.0/24 dev p9p1  proto kernel  scope link  src 10.0.5.15
70.0.0.0/24 dev p7p1  proto kernel  scope link  src 70.0.0.1
80.0.0.0/24 dev p8p1  proto kernel  scope link  src 80.0.0.1
90.0.0.0/24 via 80.0.0.2 dev p8p1  metric 1
90.0.0.0/24 via 70.0.0.2 dev p7p1  metric 2
192.168.56.0/24 dev p2p1  proto kernel  scope link  src 192.168.56.2
90.0.0.1 via 80.0.0.2 dev p8p1  src 80.0.0.1
    cache
local 80.0.0.1 dev lo  src 80.0.0.1
    cache <local>
80.0.0.2 dev p8p1  src 80.0.0.1
    cache

and the output changes to what one would expect.

If the sysctl is not set, the following output would be expected when
p8p1 is down:

default via 10.0.5.2 dev p9p1
10.0.5.0/24 dev p9p1  proto kernel  scope link  src 10.0.5.15
70.0.0.0/24 dev p7p1  proto kernel  scope link  src 70.0.0.1
80.0.0.0/24 dev p8p1  proto kernel  scope link  src 80.0.0.1 linkdown
90.0.0.0/24 via 80.0.0.2 dev p8p1  metric 1 linkdown
90.0.0.0/24 via 70.0.0.2 dev p7p1  metric 2

Since the dead flag does not appear, there should be no expectation that
the kernel would skip using this route due to link being down.

v2: Split kernel changes into 2 patches, this actually makes a
behavioral change if the sysctl is set.  Also took suggestion from Alex
to simplify code by only checking sysctl during fib lookup and
suggestion from Scott to add a per-interface sysctl.

v3: Code clean-ups to make it more readable and efficient as well as a
reverse path check fix.

v4: Drop binary sysctl

v5: Whitespace fixups from Dave

v6: Style changes from Dave and checkpatch suggestions

v7: One more checkpatch fixup

Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24 02:15:54 -07:00
Andy Gospodarek 8a3d03166f net: track link-status of ipv4 nexthops
Add a fib flag called RTNH_F_LINKDOWN to any ipv4 nexthops that are
reachable via an interface where carrier is off.  No action is taken,
but additional flags are passed to userspace to indicate carrier status.

This also includes a cleanup to fib_disable_ip to more clearly indicate
what event made the function call to replace the more cryptic force
option previously used.

v2: Split out kernel functionality into 2 patches, this patch simply
sets and clears new nexthop flag RTNH_F_LINKDOWN.

v3: Cleanups suggested by Alex as well as a bug noticed in
fib_sync_down_dev and fib_sync_up when multipath was not enabled.

v5: Whitespace and variable declaration fixups suggested by Dave.

v6: Style fixups noticed by Dave; ran checkpatch to be sure I got them
all.

Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24 02:15:54 -07:00
Julian Anastasov 34b99df4e6 ip: report the original address of ICMP messages
ICMP messages can trigger ICMP and local errors. In this case
serr->port is 0 and starting from Linux 4.0 we do not return
the original target address to the error queue readers.
Add function to define which errors provide addr_offset.
With this fix my ping command is not silent anymore.

Fixes: c247f0534c ("ip: fix error queue empty skb handling")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24 00:48:08 -07:00
Christoph Paasch dfea2aa654 tcp: Do not call tcp_fastopen_reset_cipher from interrupt context
tcp_fastopen_reset_cipher really cannot be called from interrupt
context. It allocates the tcp_fastopen_context with GFP_KERNEL and
calls crypto_alloc_cipher, which allocates all kind of stuff with
GFP_KERNEL.

Thus, we might sleep when the key-generation is triggered by an
incoming TFO cookie-request which would then happen in interrupt-
context, as shown by enabling CONFIG_DEBUG_ATOMIC_SLEEP:

[   36.001813] BUG: sleeping function called from invalid context at mm/slub.c:1266
[   36.003624] in_atomic(): 1, irqs_disabled(): 0, pid: 1016, name: packetdrill
[   36.004859] CPU: 1 PID: 1016 Comm: packetdrill Not tainted 4.1.0-rc7 #14
[   36.006085] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[   36.008250]  00000000000004f2 ffff88007f8838a8 ffffffff8171d53a ffff880075a084a8
[   36.009630]  ffff880075a08000 ffff88007f8838c8 ffffffff810967d3 ffff88007f883928
[   36.011076]  0000000000000000 ffff88007f8838f8 ffffffff81096892 ffff88007f89be00
[   36.012494] Call Trace:
[   36.012953]  <IRQ>  [<ffffffff8171d53a>] dump_stack+0x4f/0x6d
[   36.014085]  [<ffffffff810967d3>] ___might_sleep+0x103/0x170
[   36.015117]  [<ffffffff81096892>] __might_sleep+0x52/0x90
[   36.016117]  [<ffffffff8118e887>] kmem_cache_alloc_trace+0x47/0x190
[   36.017266]  [<ffffffff81680d82>] ? tcp_fastopen_reset_cipher+0x42/0x130
[   36.018485]  [<ffffffff81680d82>] tcp_fastopen_reset_cipher+0x42/0x130
[   36.019679]  [<ffffffff81680f01>] tcp_fastopen_init_key_once+0x61/0x70
[   36.020884]  [<ffffffff81680f2c>] __tcp_fastopen_cookie_gen+0x1c/0x60
[   36.022058]  [<ffffffff816814ff>] tcp_try_fastopen+0x58f/0x730
[   36.023118]  [<ffffffff81671788>] tcp_conn_request+0x3e8/0x7b0
[   36.024185]  [<ffffffff810e3872>] ? __module_text_address+0x12/0x60
[   36.025327]  [<ffffffff8167b2e1>] tcp_v4_conn_request+0x51/0x60
[   36.026410]  [<ffffffff816727e0>] tcp_rcv_state_process+0x190/0xda0
[   36.027556]  [<ffffffff81661f97>] ? __inet_lookup_established+0x47/0x170
[   36.028784]  [<ffffffff8167c2ad>] tcp_v4_do_rcv+0x16d/0x3d0
[   36.029832]  [<ffffffff812e6806>] ? security_sock_rcv_skb+0x16/0x20
[   36.030936]  [<ffffffff8167cc8a>] tcp_v4_rcv+0x77a/0x7b0
[   36.031875]  [<ffffffff816af8c3>] ? iptable_filter_hook+0x33/0x70
[   36.032953]  [<ffffffff81657d22>] ip_local_deliver_finish+0x92/0x1f0
[   36.034065]  [<ffffffff81657f1a>] ip_local_deliver+0x9a/0xb0
[   36.035069]  [<ffffffff81657c90>] ? ip_rcv+0x3d0/0x3d0
[   36.035963]  [<ffffffff81657569>] ip_rcv_finish+0x119/0x330
[   36.036950]  [<ffffffff81657ba7>] ip_rcv+0x2e7/0x3d0
[   36.037847]  [<ffffffff81610652>] __netif_receive_skb_core+0x552/0x930
[   36.038994]  [<ffffffff81610a57>] __netif_receive_skb+0x27/0x70
[   36.040033]  [<ffffffff81610b72>] process_backlog+0xd2/0x1f0
[   36.041025]  [<ffffffff81611482>] net_rx_action+0x122/0x310
[   36.042007]  [<ffffffff81076743>] __do_softirq+0x103/0x2f0
[   36.042978]  [<ffffffff81723e3c>] do_softirq_own_stack+0x1c/0x30

This patch moves the call to tcp_fastopen_init_key_once to the places
where a listener socket creates its TFO-state, which always happens in
user-context (either from the setsockopt, or implicitly during the
listen()-call)

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Fixes: 222e83d2e0 ("tcp: switch tcp_fastopen key generation to net_get_random_once")
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-23 02:38:10 -07:00
Hiroaki SHIMODA 3b1884435a inet_diag: Remove _bh suffix in inet_diag_dump_reqs().
inet_diag_dump_reqs() is called from inet_diag_dump_icsk() with BH
disabled. So no need to disable BH in inet_diag_dump_reqs().

Signed-off-by: Hiroaki Shimoda <shimoda.hiroaki@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-23 01:19:52 -07:00
Linus Torvalds 44d21c3f3a Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Here is the crypto update for 4.2:

  API:

   - Convert RNG interface to new style.

   - New AEAD interface with one SG list for AD and plain/cipher text.
     All external AEAD users have been converted.

   - New asymmetric key interface (akcipher).

  Algorithms:

   - Chacha20, Poly1305 and RFC7539 support.

   - New RSA implementation.

   - Jitter RNG.

   - DRBG is now seeded with both /dev/random and Jitter RNG.  If kernel
     pool isn't ready then DRBG will be reseeded when it is.

   - DRBG is now the default crypto API RNG, replacing krng.

   - 842 compression (previously part of powerpc nx driver).

  Drivers:

   - Accelerated SHA-512 for arm64.

   - New Marvell CESA driver that supports DMA and more algorithms.

   - Updated powerpc nx 842 support.

   - Added support for SEC1 hardware to talitos"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (292 commits)
  crypto: marvell/cesa - remove COMPILE_TEST dependency
  crypto: algif_aead - Temporarily disable all AEAD algorithms
  crypto: af_alg - Forbid the use internal algorithms
  crypto: echainiv - Only hold RNG during initialisation
  crypto: seqiv - Add compatibility support without RNG
  crypto: eseqiv - Offer normal cipher functionality without RNG
  crypto: chainiv - Offer normal cipher functionality without RNG
  crypto: user - Add CRYPTO_MSG_DELRNG
  crypto: user - Move cryptouser.h to uapi
  crypto: rng - Do not free default RNG when it becomes unused
  crypto: skcipher - Allow givencrypt to be NULL
  crypto: sahara - propagate the error on clk_disable_unprepare() failure
  crypto: rsa - fix invalid select for AKCIPHER
  crypto: picoxcell - Update to the current clk API
  crypto: nx - Check for bogus firmware properties
  crypto: marvell/cesa - add DT bindings documentation
  crypto: marvell/cesa - add support for Kirkwood and Dove SoCs
  crypto: marvell/cesa - add support for Orion SoCs
  crypto: marvell/cesa - add allhwsupport module parameter
  crypto: marvell/cesa - add support for all armada SoCs
  ...
2015-06-22 21:04:48 -07:00
Roopa Prabhu a2bb6d7d6f ipv4: include NLM_F_APPEND flag in append route notifications
This patch adds NLM_F_APPEND flag to struct nlmsg_hdr->nlmsg_flags
in newroute notifications if the route add was an append.
(This is similar to how NLM_F_REPLACE is already part of new
route replace notifications today)

This helps userspace determine if the route add operation was
an append.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21 10:23:04 -07:00
Craig Gallek e0df02e0c2 sock_diag: fetch source port from inet_sock
When an inet_sock is destroyed, its source port (sk_num) is set to
zero as part of the unhash procedure.  In order to supply a source
port as part of the NETLINK_SOCK_DIAG socket destruction broadcasts,
the source port number must be read from inet_sport instead.

Tested: ss -E
Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21 10:16:50 -07:00
Herbert Xu c0b59fafe3 Merge branch 'mvebu/drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Merge the mvebu/drivers branch of the arm-soc tree which contains
just a single patch bfa1ce5f38 ("bus:
mvebu-mbus: add mv_mbus_dram_info_nooverlap()") that happens to be
a prerequisite of the new marvell/cesa crypto driver.
2015-06-19 22:07:07 +08:00
Paul Gortmaker 5533106009 netfilter: don't use module_init/exit in core IPV4 code
The file net/ipv4/netfilter.o is created based on whether
CONFIG_NETFILTER is set.  However that is defined as a bool, and
hence this file with the core netfilter hooks will never be
modular.  So using module_init as an alias for __initcall can be
somewhat misleading.

Fix this up now, so that we can relocate module_init from
init.h into module.h in the future.  If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing.  Also add an inclusion of init.h, as
that was previously implicit here in the netfilter.c file.

Note that direct use of __initcall is discouraged, vs. one
of the priority categorized subgroups.  As __initcall gets
mapped onto device_initcall, our use of subsys_initcall (which
seems to make sense for netfilter code) will thus change this
registration from level 6-device to level 4-subsys (i.e. slightly
earlier).  However no observable impact of that small difference
has been observed during testing, or is expected. (i.e. the
location of the netfilter messages in dmesg remains unchanged
with respect to all the other surrounding messages.)

As for the module_exit, rather than replace it with __exitcall,
we simply remove it, since it appears only UML does anything
with those, and even for UML, there is no relevant cleanup
to be done here.

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netfilter-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2015-06-16 14:12:34 -04:00
Craig Gallek 35ac838a9b sock_diag: implement a get_info handler for inet
This get_info handler will simply dispatch to the appropriate
existing inet protocol handler.

This patch also includes a new netlink attribute
(INET_DIAG_PROTOCOL).  This attribute is currently only used
for multicast messages.  Without this attribute, there is no
way of knowing the IP protocol used by the socket information
being broadcast.  This attribute is not necessary in the 'dump'
variant of this protocol (though it could easily be added)
because dump requests are issued for specific family/protocol
pairs.

Tested: ss -E (note, the -E option has not yet been merged into
the upstream version of ss).

Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-15 19:49:22 -07:00
Craig Gallek 3fd22af808 sock_diag: specify info_size per inet protocol
Previously, there was no clear distinction between the inet protocols
that used struct tcp_info to report information and those that didn't.
This change adds a specific size attribute to the inet_diag_handler
struct which defines these interfaces.  This will make dispatching
sock_diag get_info requests identical for all inet protocols in a
following patch.

Tested: ss -au
Tested: ss -at
Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-15 19:49:22 -07:00
David S. Miller ada6c1de9e Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

This a bit large (and late) patchset that contains Netfilter updates for
net-next. Most relevantly br_netfilter fixes, ipset RCU support, removal of
x_tables percpu ruleset copy and rework of the nf_tables netdev support. More
specifically, they are:

1) Warn the user when there is a better protocol conntracker available, from
   Marcelo Ricardo Leitner.

2) Fix forwarding of IPv6 fragmented traffic in br_netfilter, from Bernhard
   Thaler. This comes with several patches to prepare the change in first place.

3) Get rid of special mtu handling of PPPoE/VLAN frames for br_netfilter. This
   is not needed anymore since now we use the largest fragment size to
   refragment, from Florian Westphal.

4) Restore vlan tag when refragmenting in br_netfilter, also from Florian.

5) Get rid of the percpu ruleset copy in x_tables, from Florian. Plus another
   follow up patch to refine it from Eric Dumazet.

6) Several ipset cleanups, fixes and finally RCU support, from Jozsef Kadlecsik.

7) Get rid of parens in Netfilter Kconfig files.

8) Attach the net_device to the basechain as opposed to the initial per table
   approach in the nf_tables netdev family.

9) Subscribe to netdev events to detect the removal and registration of a
   device that is referenced by a basechain.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-15 14:30:32 -07:00
Eric Dumazet 711bdde6a8 netfilter: x_tables: remove XT_TABLE_INFO_SZ and a dereference.
After Florian patches, there is no need for XT_TABLE_INFO_SZ anymore :
Only one copy of table is kept, instead of one copy per cpu.

We also can avoid a dereference if we put table data right after
xt_table_info. It reduces register pressure and helps compiler.

Then, we attempt a kmalloc() if total size is under order-3 allocation,
to reduce TLB pressure, as in many cases, rules fit in 32 KB.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-15 20:19:20 +02:00
Pablo Neira Ayuso f09becc79f netfilter: Kconfig: get rid of parens around depends on
According to the reporter, they are not needed.

Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-15 17:26:37 +02:00
Kenneth Klette Jonassen 758f0d4b16 tcp: cdg: use div_u64()
Fixes cross-compile to mips.

Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-14 12:57:45 -07:00
Florian Westphal b60f2f3d65 net: ipv4: un-inline ip_finish_output2
text    data     bss     dec     hex filename
old: 16527      44       0   16571    40bb net/ipv4/ip_output.o
new: 14935      44       0   14979    3a83 net/ipv4/ip_output.o

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-12 14:19:17 -07:00
Florian Westphal 482cfc3185 netfilter: xtables: avoid percpu ruleset duplication
We store the rule blob per (possible) cpu.  Unfortunately this means we can
waste lot of memory on big smp machines. ipt_entry structure ('rule head')
is 112 byte, so e.g. with maxcpu=64 one single rule eats
close to 8k RAM.

Since previous patch made counters percpu it appears there is nothing
left in the rule blob that needs to be percpu.

On my test system (144 possible cpus, 400k dummy rules) this
change saves close to 9 Gigabyte of RAM.

Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-12 14:27:10 +02:00
Florian Westphal 71ae0dff02 netfilter: xtables: use percpu rule counters
The binary arp/ip/ip6tables ruleset is stored per cpu.

The only reason left as to why we need percpu duplication are the rule
counters embedded into ipt_entry et al -- since each cpu has its own copy
of the rules, all counters can be lockless.

The downside is that the more cpus are supported, the more memory is
required.  Rules are not just duplicated per online cpu but for each
possible cpu, i.e. if maxcpu is 144, then rule is duplicated 144 times,
not for the e.g. 64 cores present.

To save some memory and also improve utilization of shared caches it
would be preferable to only store the rule blob once.

So we first need to separate counters and the rule blob.

Instead of using entry->counters, allocate this percpu and store the
percpu address in entry->counters.pcnt on CONFIG_SMP.

This change makes no sense as-is; it is merely an intermediate step to
remove the percpu duplication of the rule set in a followup patch.

Suggested-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-12 14:27:09 +02:00
Florian Westphal 33b1f31392 net: ip_fragment: remove BRIDGE_NETFILTER mtu special handling
since commit d6b915e29f
("ip_fragment: don't forward defragmented DF packet") the largest
fragment size is available in the IPCB.

Therefore we no longer need to care about 'encapsulation'
overhead of stripped PPPOE/VLAN headers since ip_do_fragment
doesn't use device mtu in such cases.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-12 14:16:46 +02:00
Eric Dumazet b5e2c45783 tcp: remove obsolete check in tcp_set_skb_tso_segs()
We had various issues in the past when TCP stack was modifying
gso_size/gso_segs while clones were in flight.

Commit c52e2421f7 ("tcp: must unclone packets before mangling them")
fixed these bugs and added a WARN_ON_ONCE(skb_cloned(skb)); in
tcp_set_skb_tso_segs()

These bugs are now fixed, and because TCP stack now only sets
shinfo->gso_size|segs on the clone itself, the check can be removed.

As a result of this change, compiler inlines tcp_set_skb_tso_segs() in
tcp_init_tso_segs()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 16:33:11 -07:00
Eric Dumazet f69ad292cf tcp: fill shinfo->gso_size at last moment
In commit cd7d8498c9 ("tcp: change tcp_skb_pcount() location") we stored
gso_segs in a temporary cache hot location.

This patch does the same for gso_size.

This allows to save 2 cache line misses in tcp xmit path for
the last packet that is considered but not sent because of
various conditions (cwnd, tso defer, receiver window, TSQ...)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 16:33:11 -07:00
Eric Dumazet 5bbb432c89 tcp: tcp_set_skb_tso_segs() no longer need struct sock parameter
tcp_set_skb_tso_segs() & tcp_init_tso_segs() no longer
use the sock pointer.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 16:33:11 -07:00
Eric Dumazet 51466a7545 tcp: fill shinfo->gso_type at last moment
Our goal is to touch skb_shinfo(skb) only when absolutely needed,
to avoid two cache line misses in TCP output path for last skb
that is considered but not sent because of various conditions
(cwnd, tso defer, receiver window, TSQ...)

A packet is GSO only when skb_shinfo(skb)->gso_size is not zero.

We can set skb_shinfo(skb)->gso_type to sk->sk_gso_type even for
non GSO packets.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 16:33:11 -07:00
Eric Dumazet a7eea416cb tcp: reserve tcp_skb_mss() to tcp stack
tcp_gso_segment() and tcp_gro_receive() are not strictly
part of TCP stack. They should not assume tcp_skb_mss(skb)
is in fact skb_shinfo(skb)->gso_size.

This will allow us to change tcp_skb_mss() in following patches.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 16:33:10 -07:00
Kenneth Klette Jonassen 2b0a8c9eee tcp: add CDG congestion control
CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies
the TCP sender in order to [1]:

  o Use the delay gradient as a congestion signal.
  o Back off with an average probability that is independent of the RTT.
  o Coexist with flows that use loss-based congestion control, i.e.,
    flows that are unresponsive to the delay signal.
  o Tolerate packet loss unrelated to congestion. (Disabled by default.)

Its FreeBSD implementation was presented for the ICCRG in July 2012;
slides are available at http://www.ietf.org/proceedings/84/iccrg.html

Running the experiment scenarios in [1] suggests that our implementation
achieves more goodput compared with FreeBSD 10.0 senders, although it also
causes more queueing delay for a given backoff factor.

The loss tolerance heuristic is disabled by default due to safety concerns
for its use in the Internet [2, p. 45-46].

We use a variant of the Hybrid Slow start algorithm in tcp_cubic to reduce
the probability of slow start overshoot.

[1] D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using
    delay gradients." In Networking 2011, pages 328-341. Springer, 2011.
[2] K.K. Jonassen. "Implementing CAIA Delay-Gradient in Linux."
    MSc thesis. Department of Informatics, University of Oslo, 2015.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: David Hayes <davihay@ifi.uio.no>
Cc: Andreas Petlund <apetlund@simula.no>
Cc: Dave Taht <dave.taht@bufferbloat.net>
Cc: Nicolas Kuhn <nicolas.kuhn@telecom-bretagne.eu>
Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 00:09:12 -07:00
Kenneth Klette Jonassen 7782ad8bb5 tcp: export tcp_enter_cwr()
Upcoming tcp_cdg uses tcp_enter_cwr() to initiate PRR. Export this
function so that CDG can be compiled as a module.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: David Hayes <davihay@ifi.uio.no>
Cc: Andreas Petlund <apetlund@simula.no>
Cc: Dave Taht <dave.taht@bufferbloat.net>
Cc: Nicolas Kuhn <nicolas.kuhn@telecom-bretagne.eu>
Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11 00:09:12 -07:00
Eric Dumazet f9c2ff22bb net: tcp: dctcp_update_alpha() fixes.
dctcp_alpha can be read by from dctcp_get_info() without
synchro, so use WRITE_ONCE() to prevent compiler from using
dctcp_alpha as a temporary variable.

Also, playing with small dctcp_shift_g (like 1), can expose
an overflow with 32bit values shifted 9 times before divide.

Use an u64 field to avoid this problem, and perform the divide
only if acked_bytes_ecn is not zero.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-10 23:28:33 -07:00
David S. Miller 941742f497 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-06-08 20:06:56 -07:00
Firo Yang f38b24c905 fib_trie: coding style: Use pointer after check
As Alexander Duyck pointed out that:
struct tnode {
        ...
        struct key_vector kv[1];
}
The kv[1] member of struct tnode is an arry that refernced by
a null pointer will not crash the system, like this:
struct tnode *p = NULL;
struct key_vector *kv = p->kv;
As such p->kv doesn't actually dereference anything, it is simply a
means for getting the offset to the array from the pointer p.

This patch make the code more regular to avoid making people feel
odd when they look at the code.

Signed-off-by: Firo Yang <firogm@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-07 23:45:40 -07:00
Eric Dumazet b80c0e7858 tcp: get_cookie_sock() consolidation
IPv4 and IPv6 share same implementation of get_cookie_sock(),
and there is no point inlining it.

We add tcp_ prefix to the common helper name and export it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-07 15:19:52 -07:00
Eric Dumazet 98da81a426 tcp: remove redundant checks II
For same reasons than in commit 12e25e1041 ("tcp: remove redundant
checks"), we can remove redundant checks done for timewait sockets.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-07 01:55:01 -07:00
Eric Dumazet 90c337da15 inet: add IP_BIND_ADDRESS_NO_PORT to overcome bind(0) limitations
When an application needs to force a source IP on an active TCP socket
it has to use bind(IP, port=x).

As most applications do not want to deal with already used ports, x is
often set to 0, meaning the kernel is in charge to find an available
port.
But kernel does not know yet if this socket is going to be a listener or
be connected.
It has very limited choices (no full knowledge of final 4-tuple for a
connect())

With limited ephemeral port range (about 32K ports), it is very easy to
fill the space.

This patch adds a new SOL_IP socket option, asking kernel to ignore
the 0 port provided by application in bind(IP, port=0) and only
remember the given IP address.

The port will be automatically chosen at connect() time, in a way
that allows sharing a source port as long as the 4-tuples are unique.

This new feature is available for both IPv4 and IPv6 (Thanks Neal)

Tested:

Wrote a test program and checked its behavior on IPv4 and IPv6.

strace(1) shows sequences of bind(IP=127.0.0.2, port=0) followed by
connect().
Also getsockname() show that the port is still 0 right after bind()
but properly allocated after connect().

socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 5
setsockopt(5, SOL_IP, IP_BIND_ADDRESS_NO_PORT, [1], 4) = 0
bind(5, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("127.0.0.2")}, 16) = 0
getsockname(5, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("127.0.0.2")}, [16]) = 0
connect(5, {sa_family=AF_INET, sin_port=htons(53174), sin_addr=inet_addr("127.0.0.3")}, 16) = 0
getsockname(5, {sa_family=AF_INET, sin_port=htons(38050), sin_addr=inet_addr("127.0.0.2")}, [16]) = 0

IPv6 test :

socket(PF_INET6, SOCK_STREAM, IPPROTO_IP) = 7
setsockopt(7, SOL_IP, IP_BIND_ADDRESS_NO_PORT, [1], 4) = 0
bind(7, {sa_family=AF_INET6, sin6_port=htons(0), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 0
getsockname(7, {sa_family=AF_INET6, sin6_port=htons(0), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, [28]) = 0
connect(7, {sa_family=AF_INET6, sin6_port=htons(57300), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 0
getsockname(7, {sa_family=AF_INET6, sin6_port=htons(60964), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, [28]) = 0

I was able to bind()/connect() a million concurrent IPv4 sockets,
instead of ~32000 before patch.

lpaa23:~# ulimit -n 1000010
lpaa23:~# ./bind --connect --num-flows=1000000 &
1000000 sockets

lpaa23:~# grep TCP /proc/net/sockstat
TCP: inuse 2000063 orphan 0 tw 47 alloc 2000157 mem 66

Check that a given source port is indeed used by many different
connections :

lpaa23:~# ss -t src :40000 | head -10
State      Recv-Q Send-Q   Local Address:Port          Peer Address:Port
ESTAB      0      0           127.0.0.2:40000         127.0.202.33:44983
ESTAB      0      0           127.0.0.2:40000         127.2.27.240:44983
ESTAB      0      0           127.0.0.2:40000           127.2.98.5:44983
ESTAB      0      0           127.0.0.2:40000        127.0.124.196:44983
ESTAB      0      0           127.0.0.2:40000         127.2.139.38:44983
ESTAB      0      0           127.0.0.2:40000          127.1.59.80:44983
ESTAB      0      0           127.0.0.2:40000          127.3.6.228:44983
ESTAB      0      0           127.0.0.2:40000          127.0.38.53:44983
ESTAB      0      0           127.0.0.2:40000         127.1.197.10:44983

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-06 23:57:12 -07:00
Wei Liu c39c4c6abb tcp: double default TSQ output bytes limit
Xen virtual network driver has higher latency than a physical NIC.
Having only 128K as limit for TSQ introduced 30% regression in guest
throughput.

This patch raises the limit to 256K. This reduces the regression to 8%.
This buys us more time to work out a proper solution in the long run.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 01:09:36 -07:00
Eric Dumazet 12e25e1041 tcp: remove redundant checks
tcp_v4_rcv() checks the following before calling tcp_v4_do_rcv():

if (th->doff < sizeof(struct tcphdr) / 4)
    goto bad_packet;
if (!pskb_may_pull(skb, th->doff * 4))
    goto discard_it;

So following check in tcp_v4_do_rcv() is redundant
and "goto csum_err;" is wrong anyway.

if (skb->len < tcp_hdrlen(skb) || ...)
	goto csum_err;

A second check can be removed after no_tcp_socket label for same reason.

Same tests can be removed in tcp_v6_do_rcv()

Note : short tcp frames are not properly accounted in tcpInErrs MIB,
because pskb_may_pull() failure simply drops incoming skb, we might
fix this in a separate patch.

Signed-off-by: Eric Dumazet  <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 01:04:40 -07:00
Shawn Bohrer 6e54030932 ipv4/udp: Verify multicast group is ours in upd_v4_early_demux()
421b3885bf "udp: ipv4: Add udp early
demux" introduced a regression that allowed sockets bound to INADDR_ANY
to receive packets from multicast groups that the socket had not joined.
For example a socket that had joined 224.168.2.9 could also receive
packets from 225.168.2.9 despite not having joined that group if
ip_early_demux is enabled.

Fix this by calling ip_check_mc_rcu() in udp_v4_early_demux() to verify
that the multicast packet is indeed ours.

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
Reported-by: Yurij M. Plotnikov <Yurij.Plotnikov@oktetlabs.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 00:46:26 -07:00
David S. Miller dda922c831 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/phy/amd-xgbe-phy.c
	drivers/net/wireless/iwlwifi/Kconfig
	include/net/mac80211.h

iwlwifi/Kconfig and mac80211.h were both trivial overlapping
changes.

The drivers/net/phy/amd-xgbe-phy.c file got removed in 'net-next' and
the bug fix that happened on the 'net' side is already integrated
into the rest of the amd-xgbe driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-01 22:51:30 -07:00
Neal Cardwell 9f950415e4 tcp: fix child sockets to use system default congestion control if not set
Linux 3.17 and earlier are explicitly engineered so that if the app
doesn't specifically request a CC module on a listener before the SYN
arrives, then the child gets the system default CC when the connection
is established. See tcp_init_congestion_control() in 3.17 or earlier,
which says "if no choice made yet assign the current value set as
default". The change ("net: tcp: assign tcp cong_ops when tcp sk is
created") altered these semantics, so that children got their parent
listener's congestion control even if the system default had changed
after the listener was created.

This commit returns to those original semantics from 3.17 and earlier,
since they are the original semantics from 2007 in 4d4d3d1e8 ("[TCP]:
Congestion control initialization."), and some Linux congestion
control workflows depend on that.

In summary, if a listener socket specifically sets TCP_CONGESTION to
"x", or the route locks the CC module to "x", then the child gets
"x". Otherwise the child gets current system default from
net.ipv4.tcp_congestion_control. That's the behavior in 3.17 and
earlier, and this commit restores that.

Fixes: 55d8694fa8 ("net: tcp: assign tcp cong_ops when tcp sk is created")
Cc: Florian Westphal <fw@strlen.de>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-31 21:49:14 -07:00
Eric Dumazet beb39db59d udp: fix behavior of wrong checksums
We have two problems in UDP stack related to bogus checksums :

1) We return -EAGAIN to application even if receive queue is not empty.
   This breaks applications using edge trigger epoll()

2) Under UDP flood, we can loop forever without yielding to other
   processes, potentially hanging the host, especially on non SMP.

This patch is an attempt to make things better.

We might in the future add extra support for rt applications
wanting to better control time spent doing a recv() in a hostile
environment. For example we could validate checksums before queuing
packets in socket receive queue.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-31 21:42:18 -07:00
David S. Miller 583d3f5af2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next, they are:

1) default CONFIG_NETFILTER_INGRESS to y for easier compile-testing of all
   options.

2) Allow to bind a table to net_device. This introduces the internal
   NFT_AF_NEEDS_DEV flag to perform a mandatory check for this binding.
   This is required by the next patch.

3) Add the 'netdev' table family, this new table allows you to create ingress
   filter basechains. This provides access to the existing nf_tables features
   from ingress.

4) Kill unused argument from compat_find_calc_{match,target} in ip_tables
   and ip6_tables, from Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-31 00:02:30 -07:00
Sorin Dumitru 8133534c76 net: limit tcp/udp rmem/wmem to SOCK_{RCV,SND}BUF_MIN
This is similar to b1cb59cf2efe(net: sysctl_net_core: check SNDBUF
and RCVBUF for min length). I don't think too small values can cause
crashes in the case of udp and tcp, but I've seen this set to too
small values which triggered awful performance. It also makes the
setting consistent across all the wmem/rmem sysctls.

Signed-off-by: Sorin Dumitru <sdumitru@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-30 17:37:44 -07:00
David S. Miller 5aab0e8a45 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2015-05-28

1) Fix a race in xfrm_state_lookup_byspi, we need to take
   the refcount before we release xfrm_state_lock.
   From Li RongQing.

2) Fix IV generation on ESN state. We used just the
   low order sequence numbers for IV generation on
   ESN, as a result the IV can repeat on the same
   state. Fix this by using the  high order sequence
   number bits too and make sure to always initialize
   the high order bits with zero. These patches are
   serious stable candidates. Fixes from Herbert Xu.

3) Fix the skb->mark handling on vti. We don't
   reset skb->mark in skb_scrub_packet anymore,
   so vti must care to restore the original
   value back after it was used to lookup the
   vti policy and state. Fixes from Alexander Duyck.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-28 20:41:35 -07:00
Alexander Duyck d55c670cbc ip_vti/ip6_vti: Preserve skb->mark after rcv_cb call
The vti6_rcv_cb and vti_rcv_cb calls were leaving the skb->mark modified
after completing the function.  This resulted in the original skb->mark
value being lost.  Since we only need skb->mark to be set for
xfrm_policy_check we can pull the assignment into the rcv_cb calls and then
just restore the original mark after xfrm_policy_check has been completed.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2015-05-28 06:23:32 +02:00
Alexander Duyck cd5279c194 ip_vti/ip6_vti: Do not touch skb->mark on xmit
Instead of modifying skb->mark we can simply modify the flowi_mark that is
generated as a result of the xfrm_decode_session.  By doing this we don't
need to actually touch the skb->mark and it can be preserved as it passes
out through the tunnel.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2015-05-28 06:23:31 +02:00
Herbert Xu 7021b2e1cd esp4: Switch to new AEAD interface
This patch makes use of the new AEAD interface which uses a single
SG list instead of separate lists for the AD and plain text.  The
IV generation is also now carried out through normal AEAD methods.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-05-28 11:23:20 +08:00
Eric Dumazet ed2dfd9009 tcp/dccp: warn user for preferred ip_local_port_range
After commit 07f4c90062 ("tcp/dccp: try to not exhaust
ip_local_port_range in connect()") it is advised to have an even number
of ports described in /proc/sys/net/ipv4/ip_local_port_range

This means start/end values should have a different parity.

Let's warn sysadmins of this, so that they can update their settings
if they want to.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 14:35:36 -04:00
Eric Dumazet e2baad9e4b tcp: connect() from bound sockets can be faster
__inet_hash_connect() does not use its third argument (port_offset)
if socket was already bound to a source port.

No need to perform useless but expensive md5 computations.

Reported-by: Crestez Dan Leonard <cdleonard@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 14:30:10 -04:00
Eric Dumazet 07f4c90062 tcp/dccp: try to not exhaust ip_local_port_range in connect()
A long standing problem on busy servers is the tiny available TCP port
range (/proc/sys/net/ipv4/ip_local_port_range) and the default
sequential allocation of source ports in connect() system call.

If a host is having a lot of active TCP sessions, chances are
very high that all ports are in use by at least one flow,
and subsequent bind(0) attempts fail, or have to scan a big portion of
space to find a slot.

In this patch, I changed the starting point in __inet_hash_connect()
so that we try to favor even [1] ports, leaving odd ports for bind()
users.

We still perform a sequential search, so there is no guarantee, but
if connect() targets are very different, end result is we leave
more ports available to bind(), and we spread them all over the range,
lowering time for both connect() and bind() to find a slot.

This strategy only works well if /proc/sys/net/ipv4/ip_local_port_range
is even, ie if start/end values have different parity.

Therefore, default /proc/sys/net/ipv4/ip_local_port_range was changed to
32768 - 60999 (instead of 32768 - 61000)

There is no change on security aspects here, only some poor hashing
schemes could be eventually impacted by this change.

[1] : The odd/even property depends on ip_local_port_range values parity

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 13:30:44 -04:00
Florian Westphal d6b915e29f ip_fragment: don't forward defragmented DF packet
We currently always send fragments without DF bit set.

Thus, given following setup:

mtu1500 - mtu1500:1400 - mtu1400:1280 - mtu1280
   A           R1              R2         B

Where R1 and R2 run linux with netfilter defragmentation/conntrack
enabled, then if Host A sent a fragmented packet _with_ DF set to B, R1
will respond with icmp too big error if one of these fragments exceeded
1400 bytes.

However, if R1 receives fragment sizes 1200 and 100, it would
forward the reassembled packet without refragmenting, i.e.
R2 will send an icmp error in response to a packet that was never sent,
citing mtu that the original sender never exceeded.

The other minor issue is that a refragmentation on R1 will conceal the
MTU of R2-B since refragmentation does not set DF bit on the fragments.

This modifies ip_fragment so that we track largest fragment size seen
both for DF and non-DF packets, and set frag_max_size to the largest
value.

If the DF fragment size is larger or equal to the non-df one, we will
consider the packet a path mtu probe:
We set DF bit on the reassembled skb and also tag it with a new IPCB flag
to force refragmentation even if skb fits outdev mtu.

We will also set DF bit on each fragment in this case.

Joint work with Hannes Frederic Sowa.

Reported-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 13:03:31 -04:00
Florian Westphal c5501eb340 net: ipv4: avoid repeated calls to ip_skb_dst_mtu helper
ip_skb_dst_mtu is small inline helper, but its called in several places.

before: 17061      44       0   17105    42d1 net/ipv4/ip_output.o
after:  16805      44       0   16849    41d1 net/ipv4/ip_output.o

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 13:03:30 -04:00
David S. Miller ffa915d071 ipv4: Fix fib_trie.c build, missing linux/vmalloc.h include.
We used to get this indirectly I supposed, but no longer do.

Either way, an explicit include should have been done in the
first place.

   net/ipv4/fib_trie.c: In function '__node_free_rcu':
>> net/ipv4/fib_trie.c:293:3: error: implicit declaration of function 'vfree' [-Werror=implicit-function-declaration]
      vfree(n);
      ^
   net/ipv4/fib_trie.c: In function 'tnode_alloc':
>> net/ipv4/fib_trie.c:312:3: error: implicit declaration of function 'vzalloc' [-Werror=implicit-function-declaration]
      return vzalloc(size);
      ^
>> net/ipv4/fib_trie.c:312:3: warning: return makes pointer from integer without a cast
   cc1: some warnings being treated as errors

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 00:19:03 -04:00
Eric Dumazet d6a4e26afb tcp: tcp_tso_autosize() minimum is one packet
By making sure sk->sk_gso_max_segs minimal value is one,
and sysctl_tcp_min_tso_segs minimal value is one as well,
tcp_tso_autosize() will return a non zero value.

We can then revert 843925f33f
("tcp: Do not apply TSO segment limit to non-TSO packets")
and save few cpu cycles in fast path.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-26 23:21:29 -04:00
Eric Dumazet 095dc8e0c3 tcp: fix/cleanup inet_ehash_locks_alloc()
If tcp ehash table is constrained to a very small number of buckets
(eg boot parameter thash_entries=128), then we can crash if spinlock
array has more entries.

While we are at it, un-inline inet_ehash_locks_alloc() and make
following changes :

- Budget 2 cache lines per cpu worth of 'spinlocks'
- Try to kmalloc() the array to avoid extra TLB pressure.
  (Most servers at Google allocate 8192 bytes for this hash table)
- Get rid of various #ifdef

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-26 19:48:46 -04:00
Florian Westphal 2f06550b3b netfilter: remove unused comefrom hookmask argument
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-05-26 18:40:30 +02:00
Florian Westphal cf82624432 ip: reject too-big defragmented DF-skb when forwarding
Send icmp pmtu error if we find that the largest fragment of df-skb
exceeded the output path mtu.

The ip output path will still catch this later on but we can avoid the
forward/postrouting hook traversal by rejecting right away.

This is what ipv6 already does.

Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-25 00:08:48 -04:00
Hannes Frederic Sowa a60e3cc7c9 net: make skb_splice_bits more configureable
Prepare skb_splice_bits to be able to deal with AF_UNIX sockets.

AF_UNIX sockets don't use lock_sock/release_sock and thus we have to
use a callback to make the locking and unlocking configureable.

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-25 00:06:59 -04:00
Hannes Frederic Sowa be12a1fe29 net: skbuff: add skb_append_pagefrags and use it
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-25 00:06:58 -04:00
David S. Miller 36583eb54d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/cadence/macb.c
	drivers/net/phy/phy.c
	include/linux/skbuff.h
	net/ipv4/tcp.c
	net/switchdev/switchdev.c

Switchdev was a case of RTNH_H_{EXTERNAL --> OFFLOAD}
renaming overlapping with net-next changes of various
sorts.

phy.c was a case of two changes, one adding a local
variable to a function whilst the second was removing
one.

tcp.c overlapped a deadlock fix with the addition of new tcp_info
statistic values.

macb.c involved the addition of two zyncq device entries.

skbuff.h involved adding back ipv4_daddr to nf_bridge_info
whilst net-next changes put two other existing members of
that struct into a union.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-23 01:22:35 -04:00
Michal Kubeček d4e64c2909 ipv4: fill in table id when replacing a route
When replacing an IPv4 route, tb_id member of the new fib_alias
structure is not set in the replace code path so that the new route is
ignored.

Fixes: 0ddcf43d5d ("ipv4: FIB Local/MAIN table collapse")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 14:33:17 -04:00
David S. Miller 572152adfb Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contain Netfilter fixes for your net tree, they are:

1) Fix a race in nfnetlink_log and nfnetlink_queue that can lead to a crash.
   This problem is due to wrong order in the per-net registration and netlink
   socket events. Patch from Francesco Ruggeri.

2) Make sure that counters that userspace pass us are higher than 0 in all the
   x_tables frontends. Discovered via Trinity, patch from Dave Jones.

3) Revert a patch for br_netfilter to rely on the conntrack status bits. This
   breaks stateless IPv6 NAT transformations. Patch from Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 14:25:45 -04:00
Eric W. Biederman 381c759d99 ipv4: Avoid crashing in ip_error
ip_error does not check if in_dev is NULL before dereferencing it.

IThe following sequence of calls is possible:
CPU A                          CPU B
ip_rcv_finish
    ip_route_input_noref()
        ip_route_input_slow()
                               inetdev_destroy()
    dst_input()

With the result that a network device can be destroyed while processing
an input packet.

A crash was triggered with only unicast packets in flight, and
forwarding enabled on the only network device.   The error condition
was created by the removal of the network device.

As such it is likely the that error code was -EHOSTUNREACH, and the
action taken by ip_error (if in_dev had been accessible) would have
been to not increment any counters and to have tried and likely failed
to send an icmp error as the network device is going away.

Therefore handle this weird case by just dropping the packet if
!in_dev.  It will result in dropping the packet sooner, and will not
result in an actual change of behavior.

Fixes: 251da41301 ("ipv4: Cache ip_error() routes even when not forwarding.")
Reported-by: Vittorio Gambaletta <linuxbugs@vittgam.net>
Tested-by: Vittorio Gambaletta <linuxbugs@vittgam.net>
Signed-off-by: Vittorio Gambaletta <linuxbugs@vittgam.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 14:23:40 -04:00
Eric Dumazet d654976cbf tcp: fix a potential deadlock in tcp_get_info()
Taking socket spinlock in tcp_get_info() can deadlock, as
inet_diag_dump_icsk() holds the &hashinfo->ehash_locks[i],
while packet processing can use the reverse locking order.

We could avoid this locking for TCP_LISTEN states, but lockdep would
certainly get confused as all TCP sockets share same lockdep classes.

[  523.722504] ======================================================
[  523.728706] [ INFO: possible circular locking dependency detected ]
[  523.734990] 4.1.0-dbg-DEV #1676 Not tainted
[  523.739202] -------------------------------------------------------
[  523.745474] ss/18032 is trying to acquire lock:
[  523.750002]  (slock-AF_INET){+.-...}, at: [<ffffffff81669d44>] tcp_get_info+0x2c4/0x360
[  523.758129]
[  523.758129] but task is already holding lock:
[  523.763968]  (&(&hashinfo->ehash_locks[i])->rlock){+.-...}, at: [<ffffffff816bcb75>] inet_diag_dump_icsk+0x1d5/0x6c0
[  523.774661]
[  523.774661] which lock already depends on the new lock.
[  523.774661]
[  523.782850]
[  523.782850] the existing dependency chain (in reverse order) is:
[  523.790326]
-> #1 (&(&hashinfo->ehash_locks[i])->rlock){+.-...}:
[  523.796599]        [<ffffffff811126bb>] lock_acquire+0xbb/0x270
[  523.802565]        [<ffffffff816f5868>] _raw_spin_lock+0x38/0x50
[  523.808628]        [<ffffffff81665af8>] __inet_hash_nolisten+0x78/0x110
[  523.815273]        [<ffffffff816819db>] tcp_v4_syn_recv_sock+0x24b/0x350
[  523.822067]        [<ffffffff81684d41>] tcp_check_req+0x3c1/0x500
[  523.828199]        [<ffffffff81682d09>] tcp_v4_do_rcv+0x239/0x3d0
[  523.834331]        [<ffffffff816842fe>] tcp_v4_rcv+0xa8e/0xc10
[  523.840202]        [<ffffffff81658fa3>] ip_local_deliver_finish+0x133/0x3e0
[  523.847214]        [<ffffffff81659a9a>] ip_local_deliver+0xaa/0xc0
[  523.853440]        [<ffffffff816593b8>] ip_rcv_finish+0x168/0x5c0
[  523.859624]        [<ffffffff81659db7>] ip_rcv+0x307/0x420

Lets use u64_sync infrastructure instead. As a bonus, 64bit
arches get optimized, as these are nop for them.

Fixes: 0df48c26d8 ("tcp: add tcpi_bytes_acked to tcp_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 13:46:06 -04:00
Marcelo Ricardo Leitner 2efd055c53 tcp: add tcpi_segs_in and tcpi_segs_out to tcp_info
This patch tracks the total number of inbound and outbound segments on a
TCP socket. One may use this number to have an idea on connection
quality when compared against the retransmissions.

RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut

These are a 32bit field each and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->segs_out was placed near tp->snd_nxt for good data
locality and minimal performance impact, while tp->segs_in was placed
near tp->bytes_received for the same reason.

Join work with Eric Dumazet.

Note that received SYN are accounted on the listener, but sent SYNACK
are not accounted.

Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 23:25:21 -04:00
Eric Dumazet 946f9eb226 tcp: improve REUSEADDR/NOREUSEADDR cohabitation
inet_csk_get_port() randomization effort tends to spread
sockets on all the available range (ip_local_port_range)

This is unfortunate because SO_REUSEADDR sockets have
less requirements than non SO_REUSEADDR ones.

If an application uses SO_REUSEADDR hint, it is to try to
allow source ports being shared.

So instead of picking a random port number in ip_local_port_range,
lets try first in first half of the range.

This gives more chances to use upper half of the range for the
sockets with strong requirements (not using SO_REUSEADDR)

Note this patch does not add a new sysctl, and only changes
the way we try to pick port number.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Flavio Leitner <fbl@redhat.com>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:55:32 -04:00
Eric Dumazet f5af1f57a2 inet_hashinfo: remove bsocket counter
We no longer need bsocket atomic counter, as inet_csk_get_port()
calls bind_conflict() regardless of its value, after commit
2b05ad33e1 ("tcp: bind() fix autoselection to share ports")

This patch removes overhead of maintaining this counter and
double inet_csk_get_port() calls under pressure.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Flavio Leitner <fbl@redhat.com>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:55:32 -04:00
Jason Baron ce5ec44099 tcp: ensure epoll edge trigger wakeup when write queue is empty
We currently rely on the setting of SOCK_NOSPACE in the write()
path to ensure that we wake up any epoll edge trigger waiters when
acks return to free space in the write queue. However, if we fail
to allocate even a single skb in the write queue, we could end up
waiting indefinitely.

Fix this by explicitly issuing a wakeup when we detect the condition
of an empty write queue and a return value of -EAGAIN. This allows
userspace to re-try as we expect this to be a temporary failure.

I've tested this approach by artificially making
sk_stream_alloc_skb() return NULL periodically. In that case,
epoll edge trigger waiters will hang indefinitely in epoll_wait()
without this patch.

Signed-off-by: Jason Baron <jbaron@akamai.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:52:47 -04:00
Eric Dumazet eb9344781a tcp: add a force_schedule argument to sk_stream_alloc_skb()
In commit 8e4d980ac2 ("tcp: fix behavior for epoll edge trigger")
we fixed a possible hang of TCP sockets under memory pressure,
by allowing sk_stream_alloc_skb() to use sk_forced_mem_schedule()
if no packet is in socket write queue.

It turns out there are other cases where we want to force memory
schedule :

tcp_fragment() & tso_fragment() need to split a big TSO packet into
two smaller ones. If we block here because of TCP memory pressure,
we can effectively block TCP socket from sending new data.
If no further ACK is coming, this hang would be definitive, and socket
has no chance to effectively reduce its memory usage.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 16:56:40 -04:00
Dave Jones 1086bbe97a netfilter: ensure number of counters is >0 in do_replace()
After improving setsockopt() coverage in trinity, I started triggering
vmalloc failures pretty reliably from this code path:

warn_alloc_failed+0xe9/0x140
__vmalloc_node_range+0x1be/0x270
vzalloc+0x4b/0x50
__do_replace+0x52/0x260 [ip_tables]
do_ipt_set_ctl+0x15d/0x1d0 [ip_tables]
nf_setsockopt+0x65/0x90
ip_setsockopt+0x61/0xa0
raw_setsockopt+0x16/0x60
sock_common_setsockopt+0x14/0x20
SyS_setsockopt+0x71/0xd0

It turns out we don't validate that the num_counters field in the
struct we pass in from userspace is initialized.

The same problem also exists in ebtables, arptables, ipv6, and the
compat variants.

Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-05-20 13:46:49 +02:00
Daniel Borkmann 492135557d tcp: add rfc3168, section 6.1.1.1. fallback
This work as a follow-up of commit f7b3bec6f5 ("net: allow setting ecn
via routing table") and adds RFC3168 section 6.1.1.1. fallback for outgoing
ECN connections. In other words, this work adds a retry with a non-ECN
setup SYN packet, as suggested from the RFC on the first timeout:

  [...] A host that receives no reply to an ECN-setup SYN within the
  normal SYN retransmission timeout interval MAY resend the SYN and
  any subsequent SYN retransmissions with CWR and ECE cleared. [...]

Schematic client-side view when assuming the server is in tcp_ecn=2 mode,
that is, Linux default since 2009 via commit 255cac91c3 ("tcp: extend
ECN sysctl to allow server-side only ECN"):

 1) Normal ECN-capable path:

    SYN ECE CWR ----->
                <----- SYN ACK ECE
            ACK ----->

 2) Path with broken middlebox, when client has fallback:

    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)
            SYN ----->
                <----- SYN ACK
            ACK ----->

In case we would not have the fallback implemented, the middlebox drop
point would basically end up as:

    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)
    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)
    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)

In any case, it's rather a smaller percentage of sites where there would
occur such additional setup latency: it was found in end of 2014 that ~56%
of IPv4 and 65% of IPv6 servers of Alexa 1 million list would negotiate
ECN (aka tcp_ecn=2 default), 0.42% of these webservers will fail to connect
when trying to negotiate with ECN (tcp_ecn=1) due to timeouts, which the
fallback would mitigate with a slight latency trade-off. Recent related
paper on this topic:

  Brian Trammell, Mirja Kühlewind, Damiano Boppart, Iain Learmonth,
  Gorry Fairhurst, and Richard Scheffenegger:
    "Enabling Internet-Wide Deployment of Explicit Congestion Notification."
    Proc. PAM 2015, New York.
  http://ecn.ethz.ch/ecn-pam15.pdf

Thus, when net.ipv4.tcp_ecn=1 is being set, the patch will perform RFC3168,
section 6.1.1.1. fallback on timeout. For users explicitly not wanting this
which can be in DC use case, we add a net.ipv4.tcp_ecn_fallback knob that
allows for disabling the fallback.

tp->ecn_flags are not being cleared in tcp_ecn_clear_syn() on output, but
rather we let tcp_ecn_rcv_synack() take that over on input path in case a
SYN ACK ECE was delayed. Thus a spurious SYN retransmission will not prevent
ECN being negotiated eventually in that case.

Reference: https://www.ietf.org/proceedings/92/slides/slides-92-iccrg-1.pdf
Reference: https://www.ietf.org/proceedings/89/slides/slides-89-tsvarea-1.pdf
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mirja Kühlewind <mirja.kuehlewind@tik.ee.ethz.ch>
Signed-off-by: Brian Trammell <trammell@tik.ee.ethz.ch>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Dave That <dave.taht@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 16:53:37 -04:00
Yuchung Cheng b7b0ed910c tcp: don't over-send F-RTO probes
After sending the new data packets to probe (step 2), F-RTO may
incorrectly send more probes if the next ACK advances SND_UNA and
does not sack new packet. However F-RTO RFC 5682 probes at most
once. This bug may cause sender to always send new data instead of
repairing holes, inducing longer HoL blocking on the receiver for
the application.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 16:36:57 -04:00
Yuchung Cheng da34ac7626 tcp: only undo on partial ACKs in CA_Loss
Undo based on TCP timestamps should only happen on ACKs that advance
SND_UNA, according to the Eifel algorithm in RFC 3522:

Section 3.2:

  (4) If the value of the Timestamp Echo Reply field of the
      acceptable ACK's Timestamps option is smaller than the
      value of RetransmitTS, then proceed to step (5),

Section Terminology:
   We use the term 'acceptable ACK' as defined in [RFC793].  That is an
   ACK that acknowledges previously unacknowledged data.

This is because upon receiving an out-of-order packet, the receiver
returns the last timestamp that advances RCV_NXT, not the current
timestamp of the packet in the DUPACK. Without checking the flag,
the DUPACK will cause tcp_packet_delayed() to return true and
tcp_try_undo_loss() will revert cwnd reduction.

Note that we check the condition in CA_Recovery already by only
calling tcp_try_undo_partial() if FLAG_SND_UNA_ADVANCED is set or
tcp_try_undo_recovery() if snd_una crosses high_seq.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 16:36:57 -04:00
Eric B Munson aea0929e51 tcp: Return error instead of partial read for saved syn headers
Currently the getsockopt() requesting the cached contents of the syn
packet headers will fail silently if the caller uses a buffer that is
too small to contain the requested data.  Rather than fail silently and
discard the headers, getsockopt() should return an error and report the
required size to hold the data.

Signed-off-by: Eric B Munson <emunson@akamai.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 16:33:34 -04:00
Andy Zhou 49d16b23cd bridge_netfilter: No ICMP packet on IPv4 fragmentation error
When bridge netfilter re-fragments an IP packet for output, all
packets that can not be re-fragmented to their original input size
should be silently discarded.

However, current bridge netfilter output path generates an ICMP packet
with 'size exceeded MTU' message for such packets, this is a bug.

This patch refactors the ip_fragment() API to allow two separate
use cases. The bridge netfilter user case will not
send ICMP, the routing output will, as before.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 00:15:39 -04:00
Andy Zhou 8bc04864ac IPv4: skip ICMP for bridge contrack users when defrag expires
users in [IP_DEFRAG_CONNTRACK_BRIDGE_IN, __IP_DEFRAG_CONNTRACK_BR_IN]
should not ICMP message also.

Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 00:15:27 -04:00
Andy Zhou 5cf4228082 ipv4: introduce frag_expire_skip_icmp()
Improve readability of skip ICMP for de-fragmentation expiration logic.
This change will also make the logic easier to maintain when the
following patches in this series are applied.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 00:15:26 -04:00
David S. Miller 0bc4c07046 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next. Briefly
speaking, cleanups and minor fixes for ipset from Jozsef Kadlecsik and
Serget Popovich, more incremental updates to make br_netfilter a better
place from Florian Westphal, ARP support to the x_tables mark match /
target from and context Zhang Chunyu and the addition of context to know
that the x_tables runs through nft_compat. More specifically, they are:

1) Fix sparse warning in ipset/ip_set_hash_ipmark.c when fetching the
   IPSET_ATTR_MARK netlink attribute, from Jozsef Kadlecsik.

2) Rename STREQ macro to STRNCMP in ipset, also from Jozsef.

3) Use skb->network_header to calculate the transport offset in
   ip_set_get_ip{4,6}_port(). From Alexander Drozdov.

4) Reduce memory consumption per element due to size miscalculation,
   this patch and follow up patches from Sergey Popovich.

5) Expand nomatch field from 1 bit to 8 bits to allow to simplify
   mtype_data_reset_flags(), also from Sergey.

6) Small clean for ipset macro trickery.

7) Fix error reporting when both ip_set_get_hostipaddr4() and
   ip_set_get_extensions() from per-set uadt functions.

8) Simplify IPSET_ATTR_PORT netlink attribute validation.

9) Introduce HOST_MASK instead of hardcoded 32 in ipset.

10) Return true/false instead of 0/1 in functions that return boolean
    in the ipset code.

11) Validate maximum length of the IPSET_ATTR_COMMENT netlink attribute.

12) Allow to dereference from ext_*() ipset macros.

13) Get rid of incorrect definitions of HKEY_DATALEN.

14) Include linux/netfilter/ipset/ip_set.h in the x_tables set match.

15) Reduce nf_bridge_info size in br_netfilter, from Florian Westphal.

16) Release nf_bridge_info after POSTROUTING since this is only needed
    from the physdev match, also from Florian.

17) Reduce size of ipset code by deinlining ip_set_put_extensions(),
    from Denys Vlasenko.

18) Oneliner to add ARP support to the x_tables mark match/target, from
    Zhang Chunyu.

19) Add context to know if the x_tables extension runs from nft_compat,
    to address minor problems with three existing extensions.

20) Correct return value in several seqfile *_show() functions in the
    netfilter tree, from Joe Perches.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-18 14:47:36 -04:00
Florent Fourcot 21858cd02d tcp/ipv6: fix flow label setting in TIME_WAIT state
commit 1d13a96c74 ("ipv6: tcp: fix flowlabel value in ACK messages
send from TIME_WAIT") added the flow label in the last TCP packets.
Unfortunately, it was not casted properly.

This patch replace the buggy shift with be32_to_cpu/cpu_to_be32.

Fixes: 1d13a96c74 ("ipv6: tcp: fix flowlabel value in ACK messages")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Florent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 23:41:59 -04:00
Eric Dumazet b66e91ccbc tcp: halves tcp_mem[] limits
Allowing tcp to use ~19% of physical memory is way too much,
and allowed bugs to be hidden. Add to this that some drivers use a full
page per incoming frame, so real cost can be twice the advertized one.

Reduce tcp_mem by 50 % as a first step to sanity.

tcp_mem[0,1,2] defaults are now 4.68%, 6.25%, 9.37% of physical memory.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 22:45:49 -04:00
Eric Dumazet 76dfa60820 tcp: allow one skb to be received per socket under memory pressure
While testing tight tcp_mem settings, I found tcp sessions could be
stuck because we do not allow even one skb to be received on them.

By allowing one skb to be received, we introduce fairness and
eventuallu force memory hogs to release their allocation.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 22:45:49 -04:00
Eric Dumazet 8e4d980ac2 tcp: fix behavior for epoll edge trigger
Under memory pressure, tcp_sendmsg() can fail to queue a packet
while no packet is present in write queue. If we return -EAGAIN
with no packet in write queue, no ACK packet will ever come
to raise EPOLLOUT.

We need to allow one skb per TCP socket, and make sure that
tcp sockets can release their forward allocations under pressure.

This is a followup to commit 790ba4566c ("tcp: set SOCK_NOSPACE
under memory pressure")

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 22:45:48 -04:00
Eric Dumazet b8da51ebb1 tcp: introduce tcp_under_memory_pressure()
Introduce an optimized version of sk_under_memory_pressure()
for TCP. Our intent is to use it in fast paths.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 22:45:48 -04:00
Eric Dumazet a6c5ea4ccf tcp: rename sk_forced_wmem_schedule() to sk_forced_mem_schedule()
We plan to use sk_forced_wmem_schedule() in input path as well,
so make it non static and rename it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 22:45:48 -04:00
Eric Dumazet ba6d05641c netfilter: synproxy: fix sparse errors
Fix verbose sparse errors :

make C=2 CF=-D__CHECK_ENDIAN__ net/ipv4/netfilter/ipt_SYNPROXY.o

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 13:08:29 -04:00
Eric Dumazet 252a8fbe81 ipip: fix one sparse error
make C=2 CF=-D__CHECK_ENDIAN__ net/ipv4/ipip.o
  CHECK   net/ipv4/ipip.c
net/ipv4/ipip.c:254:27: warning: incorrect type in assignment (different base types)
net/ipv4/ipip.c:254:27:    expected restricted __be32 [addressable] [usertype] o_key
net/ipv4/ipip.c:254:27:    got restricted __be16 [addressable] [usertype] i_flags

Fixes: 3b7b514f44 ("ipip: fix a regression in ioctl")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 13:08:29 -04:00
Pablo Neira Ayuso 55917a21d0 netfilter: x_tables: add context to know if extension runs from nft_compat
Currently, we have four xtables extensions that cannot be used from the
xt over nft compat layer. The problem is that they need real access to
the full blown xt_entry to validate that the rule comes with the right
dependencies. This check was introduced to overcome the lack of
sufficient userspace dependency validation in iptables.

To resolve this problem, this patch introduces a new field to the
xt_tgchk_param structure that tell us if the extension is run from
nft_compat context.

The three affected extensions are:

1) CLUSTERIP, this target has been superseded by xt_cluster. So just
   bail out by returning -EINVAL.

2) TCPMSS. Relax the checking when used from nft_compat. If used with
   the wrong configuration, it will corrupt !syn packets by adding TCP
   MSS option.

3) ebt_stp. Relax the check to make sure it uses the reserved
   destination MAC address for STP.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tested-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
2015-05-15 20:14:07 +02:00
Roopa Prabhu eea39946a1 rename RTNH_F_EXTERNAL to RTNH_F_OFFLOAD
RTNH_F_EXTERNAL today is printed as "offload" in iproute2 output.

This patch renames the flag to be consistent with what the user sees.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14 22:45:39 -04:00
Alexander Duyck c24a59649f ip_tunnel: Report Rx dropped in ip_tunnel_get_stats64
The rx_dropped stat wasn't being reported when ip_tunnel_get_stats64 was
called.  This was leading to some confusing results in my debug as I was
seeing rx_errors increment but no other value which pointed me toward the
type of error being seen.

This change corrects that by using netdev_stats_to_stats64 to copy all
available dev stats instead of just the few that were hand picked.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14 22:30:54 -04:00
John W. Linville d37d29c305 geneve_core: identify as driver library in modules description
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:59:13 -04:00
John W. Linville 11e1fa46b4 geneve: Rename support library as geneve_core
net/ipv4/geneve.c -> net/ipv4/geneve_core.c

This name better reflects the purpose of the module.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:59:13 -04:00
John W. Linville 35d32e8fe4 geneve: move definition of geneve_hdr() to geneve.h
This is a static inline with identical definitions in multiple places...

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:59:13 -04:00
John W. Linville 125907ae5e geneve: remove MODULE_ALIAS_RTNL_LINK from net/ipv4/geneve.c
This file is essentially a library for implementing the geneve
encapsulation protocol.  The file does not register any rtnl_link_ops,
so the MODULE_ALIAS_RTNL_LINK macro is inappropriate here.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:59:12 -04:00
Eric Dumazet 7d771aaac7 ipv4: __ip_local_out_sk() is static
__ip_local_out_sk() is only used from net/ipv4/ip_output.c

net/ipv4/ip_output.c:94:5: warning: symbol '__ip_local_out_sk' was not
declared. Should it be static?

Fixes: 7026b1ddb6 ("netfilter: Pass socket pointer down through okfn().")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:21:33 -04:00
Eric Dumazet 216f8bb9f6 tcp/dccp: tw_timer_handler() is static
tw_timer_handler() is only used from net/ipv4/inet_timewait_sock.c

Fixes: 789f558cfb ("tcp/dccp: get rid of central timewait timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:21:33 -04:00
Herbert Xu 64aa42338e esp4: Use high-order sequence number bits for IV generation
I noticed we were only using the low-order bits for IV generation
when ESN is enabled.  This is very bad because it means that the
IV can repeat.  We must use the full 64 bits.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2015-05-13 09:34:53 +02:00
Jiri Pirko ebb9a03a59 switchdev: s/netdev_switch_/switchdev_/ and s/NETDEV_SWITCH_/SWITCHDEV_/
Turned out that "switchdev" sticks. So just unify all related terms to use
this prefix.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-12 18:43:52 -04:00
Eric W. Biederman 26abe14379 net: Modify sk_alloc to not reference count the netns of kernel sockets.
Now that sk_alloc knows when a kernel socket is being allocated modify
it to not reference count the network namespace of kernel sockets.

Keep track of if a socket needs reference counting by adding a flag to
struct sock called sk_net_refcnt.

Update all of the callers of sock_create_kern to stop using
sk_change_net and sk_release_kernel as those hacks are no longer
needed, to avoid reference counting a kernel socket.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:50:18 -04:00
Eric W. Biederman 11aa9c28b4 net: Pass kern from net_proto_family.create to sk_alloc
In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:50:17 -04:00
Eric W. Biederman eeb1bd5c40 net: Add a struct net parameter to sock_create_kern
This is long overdue, and is part of cleaning up how we allocate kernel
sockets that don't reference count struct net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:50:17 -04:00
Eric Dumazet e520af48c7 tcp: add TCPWinProbe and TCPKeepAlive SNMP counters
Diagnosing problems related to Window Probes has been hard because
we lack a counter.

TCPWinProbe counts the number of ACK packets a sender has to send
at regular intervals to make sure a reverse ACK packet opening back
a window had not been lost.

TCPKeepAlive counts the number of ACK packets sent to keep TCP
flows alive (SO_KEEPALIVE)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09 16:42:32 -04:00
Eric Dumazet 21c8fe9915 tcp: adjust window probe timers to safer values
With the advent of small rto timers in datacenter TCP,
(ip route ... rto_min x), the following can happen :

1) Qdisc is full, transmit fails.

   TCP sets a timer based on icsk_rto to retry the transmit, without
   exponential backoff.
   With low icsk_rto, and lot of sockets, all cpus are servicing timer
   interrupts like crazy.
   Intent of the code was to retry with a timer between 200 (TCP_RTO_MIN)
   and 500ms (TCP_RESOURCE_PROBE_INTERVAL)

2) Receivers can send zero windows if they don't drain their receive queue.

   TCP sends zero window probes, based on icsk_rto current value, with
   exponential backoff.
   With /proc/sys/net/ipv4/tcp_retries2 being 15 (or even smaller in
   some cases), sender can abort in less than one or two minutes !
   If receiver stops the sender, it obviously doesn't care of very tight
   rto. Probability of dropping the ACK reopening the window is not
   worth the risk.

Lets change the base timer to be at least 200ms (TCP_RTO_MIN) for these
events (but not normal RTO based retransmits)

A followup patch adds a new SNMP counter, as it would have helped a lot
diagnosing this issue.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09 16:42:32 -04:00
Eric Dumazet 31ccd0e66d tcp_westwood: fix tcp_westwood_info()
I forgot to update tcp_westwood when changing get_info() behavior,
this patch should fix this.

Fixes: 64f40ff5bb ("tcp: prepare CC get_info() access from getsockopt()")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-05 19:50:09 -04:00
Alexander Duyck d181ddca89 ipv4/ip_tunnel_core: Use eth_proto_is_802_3
Replace "ntohs(proto) >= ETH_P_802_3_MIN" w/ eth_proto_is_802_3(proto).

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-05 19:24:42 -04:00
Eric Dumazet cd8ae85299 tcp: provide SYN headers for passive connections
This patch allows a server application to get the TCP SYN headers for
its passive connections.  This is useful if the server is doing
fingerprinting of clients based on SYN packet contents.

Two socket options are added: TCP_SAVE_SYN and TCP_SAVED_SYN.

The first is used on a socket to enable saving the SYN headers
for child connections. This can be set before or after the listen()
call.

The latter is used to retrieve the SYN headers for passive connections,
if the parent listener has enabled TCP_SAVE_SYN.

TCP_SAVED_SYN is read once, it frees the saved SYN headers.

The data returned in TCP_SAVED_SYN are network (IPv4/IPv6) and TCP
headers.

Original patch was written by Tom Herbert, I changed it to not hold
a full skb (and associated dst and conntracking reference).

We have used such patch for about 3 years at Google.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Tested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-05 16:02:34 -04:00
David S. Miller 73e84313ee Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next
Johan Hedberg says:

====================
pull request: bluetooth-next 2015-05-04

Here's the first bluetooth-next pull request for 4.2:

 - Various fixes for at86rf230 driver
 - ieee802154: trace events support for rdev->ops
 - HCI UART driver refactoring
 - New Realtek IDs added to btusb driver
 - Off-by-one fix for rtl8723b in btusb driver
 - Refactoring of btbcm driver for both UART & USB use

Please let me know if there are any issues pulling. Thanks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04 15:36:07 -04:00
Linus Lüssing 9afd85c9e4 net: Export IGMP/MLD message validation code
With this patch, the IGMP and MLD message validation functions are moved
from the bridge code to IPv4/IPv6 multicast files. Some small
refactoring was done to enhance readibility and to iron out some
differences in behaviour between the IGMP and MLD parsing code (e.g. the
skb-cloning of MLD messages is now only done if necessary, just like the
IGMP part always did).

Finally, these IGMP and MLD message validation functions are exported so
that not only the bridge can use it but batman-adv later, too.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04 14:49:23 -04:00
Andrew Lunn 6a21165480 net: ipv4: route: Fix sending IGMP messages with link address
In setups with a global scope address on an interface, and a lesser
scope address on an interface sending IGMP reports, the reports can be
sent using the other interfaces global scope address rather than the
local interface address. RFC 2236 suggests:

     Ignore the Report if you cannot identify the source address of
     the packet as belonging to a subnet assigned to the interface on
     which the packet was received.

since such reports could be forged.

Look at the protocol when deciding if a RT_SCOPE_LINK address should
be used for the packet.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04 00:04:08 -04:00
Kenneth Klette Jonassen 138998fdd1 tcp: invoke pkts_acked hook on every ACK
Invoking pkts_acked is currently conditioned on FLAG_ACKED:
receiving a cumulative ACK of new data, or ACK with SYN flag set.

Remove this condition so that CC may get RTT measurements from all SACKs.

Cc: Yuchung Cheng <ycheng@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-03 23:18:01 -04:00
Kenneth Klette Jonassen 31231a8a87 tcp: improve RTT from SACK for CC
tcp_sacktag_one() always picks the earliest sequence SACKed for RTT.
This might not make sense for congestion control in cases where:

  1. ACKs are lost, i.e. a SACK following a lost SACK covers both
     new and old segments at the receiver.
  2. The receiver disregards the RFC 5681 recommendation to immediately
     ACK out-of-order segments.

Give congestion control a RTT for the latest segment SACKed, which is the
most accurate RTT estimate, but preserve the conservative RTT for RTO.

Removes the call to skb_mstamp_get() in tcp_sacktag_one().

Cc: Yuchung Cheng <ycheng@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-03 23:18:01 -04:00
Kenneth Klette Jonassen 196da97475 tcp: move struct tcp_sacktag_state to tcp_ack()
Later patch passes two values set in tcp_sacktag_one() to
tcp_clean_rtx_queue(). Prepare passing them via struct tcp_sacktag_state.

Acked-by: Yuchung Cheng <ycheng@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-03 23:18:01 -04:00
Li RongQing 7eee8cd4d8 ipv4: remove the unnecessary codes in fib_info_hash_move
The whole hlist will be moved, so not need to call hlist_del before
add the hlist_node to other hlist_head.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-02 22:17:44 -04:00
David S. Miller 3715544750 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge net into net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-02 22:05:58 -04:00
David S. Miller a134f083e7 ipv4: Missing sk_nulls_node_init() in ping_unhash().
If we don't do that, then the poison value is left in the ->pprev
backlink.

This can cause crashes if we do a disconnect, followed by a connect().

Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Wen Xu <hotdog3645@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-01 22:02:47 -04:00
Eric Dumazet 355b590ca2 ipv4: speedup ip_idents_reserve()
Under stress, ip_idents_reserve() is accessing a contended
cache line twice, with non optimal MESI transactions.

If we place timestamps in separate location, we reduce this
pressure by ~50% and allow atomic_add_return() to issue
a Request for Ownership.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-01 19:44:00 -04:00
Eric Dumazet f828ad0ce2 tcp_westwood: fix tcp_westwood_info()
I forgot to update tcp_westwood when changing get_info() behavior,
this patch should fix this.

Fixes: 64f40ff5bb ("tcp: prepare CC get_info() access from getsockopt()")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-30 00:27:44 -04:00
Yuchung Cheng 9dac883544 tcp: update reordering first before detecting loss
tcp_mark_lost_retrans is not used when FACK is disabled. Since
tcp_update_reordering may disable FACK, it should be called first
before tcp_mark_lost_retrans.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29 17:10:38 -04:00
Eric Dumazet 6e9250f59e tcp: add TCP_CC_INFO socket option
Some Congestion Control modules can provide per flow information,
but current way to get this information is to use netlink.

Like TCP_INFO, let's add TCP_CC_INFO so that applications can
issue a getsockopt() if they have a socket file descriptor,
instead of playing complex netlink games.

Sample usage would be :

  union tcp_cc_info info;
  socklen_t len = sizeof(info);

  if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29 17:10:38 -04:00
Eric Dumazet 64f40ff5bb tcp: prepare CC get_info() access from getsockopt()
We would like that optional info provided by Congestion Control
modules using netlink can also be read using getsockopt()

This patch changes get_info() to put this information in a buffer,
instead of skb, like tcp_get_info(), so that following patch
can reuse this common infrastructure.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29 17:10:38 -04:00
Eric Dumazet bdd1f9edac tcp: add tcpi_bytes_received to tcp_info
This patch tracks total number of payload bytes received on a TCP socket.
This is the sum of all changes done to tp->rcv_nxt

RFC4898 named this : tcpEStatsAppHCThruOctetsReceived

This is a 64bit field, and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->bytes_received was placed near tp->rcv_nxt for
best data locality and minimal performance impact.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Eric Salo <salo@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29 17:10:37 -04:00
Eric Dumazet 0df48c26d8 tcp: add tcpi_bytes_acked to tcp_info
This patch tracks total number of bytes acked for a TCP socket.
This is the sum of all changes done to tp->snd_una, and allows
for precise tracking of delivered data.

RFC4898 named this : tcpEStatsAppHCThruOctetsAcked

This is a 64bit field, and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->bytes_acked was placed near tp->snd_una for
best data locality and minimal performance impact.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Eric Salo <salo@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29 17:10:37 -04:00
Herbert Xu cb6ccf09d6 route: Use ipv4_mtu instead of raw rt_pmtu
The commit 3cdaa5be9e ("ipv4: Don't
increase PMTU with Datagram Too Big message") broke PMTU in cases
where the rt_pmtu value has expired but is smaller than the new
PMTU value.

This obsolete rt_pmtu then prevents the new PMTU value from being
installed.

Fixes: 3cdaa5be9e ("ipv4: Don't increase PMTU with Datagram Too Big message")
Reported-by: Gerd v. Egidy <gerd.von.egidy@intra2net.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29 14:43:22 -04:00
Eric Dumazet b357a364c5 inet: fix possible panic in reqsk_queue_unlink()
[ 3897.923145] BUG: unable to handle kernel NULL pointer dereference at
 0000000000000080
[ 3897.931025] IP: [<ffffffffa9f27686>] reqsk_timer_handler+0x1a6/0x243

There is a race when reqsk_timer_handler() and tcp_check_req() call
inet_csk_reqsk_queue_unlink() on the same req at the same time.

Before commit fa76ce7328 ("inet: get rid of central tcp/dccp listener
timer"), listener spinlock was held and race could not happen.

To solve this bug, we change reqsk_queue_unlink() to not assume req
must be found, and we return a status, to conditionally release a
refcount on the request sock.

This also means tcp_check_req() in non fastopen case might or not
consume req refcount, so tcp_v6_hnd_req() & tcp_v4_hnd_req() have
to properly handle this.

(Same remark for dccp_check_req() and its callers)

inet_csk_reqsk_queue_drop() is now too big to be inlined, as it is
called 4 times in tcp and 3 times in dccp.

Fixes: fa76ce7328 ("inet: get rid of central tcp/dccp listener timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-24 11:39:15 -04:00
Eric Dumazet 845704a535 tcp: avoid looping in tcp_send_fin()
Presence of an unbound loop in tcp_send_fin() had always been hard
to explain when analyzing crash dumps involving gigantic dying processes
with millions of sockets.

Lets try a different strategy :

In case of memory pressure, try to add the FIN flag to last packet
in write queue, even if packet was already sent. TCP stack will
be able to deliver this FIN after a timeout event. Note that this
FIN being delivered by a retransmit, it also carries a Push flag
given our current implementation.

By checking sk_under_memory_pressure(), we anticipate that cooking
many FIN packets might deplete tcp memory.

In the case we could not allocate a packet, even with __GFP_WAIT
allocation, then not sending a FIN seems quite reasonable if it allows
to get rid of this socket, free memory, and not block the process from
eventually doing other useful work.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-24 11:06:48 -04:00