Commit Graph

74 Commits

Author SHA1 Message Date
Jason Gunthorpe 299ee123e1 sctp: Fixup v4mapped behaviour to comply with Sock API
The SCTP socket extensions API document describes the v4mapping option as
follows:

8.1.15.  Set/Clear IPv4 Mapped Addresses (SCTP_I_WANT_MAPPED_V4_ADDR)

   This socket option is a Boolean flag which turns on or off the
   mapping of IPv4 addresses.  If this option is turned on, then IPv4
   addresses will be mapped to V6 representation.  If this option is
   turned off, then no mapping will be done of V4 addresses and a user
   will receive both PF_INET6 and PF_INET type addresses on the socket.
   See [RFC3542] for more details on mapped V6 addresses.

This description isn't really in line with what the code does though.

Introduce addr_to_user (renamed addr_v4map), which should be called
before any sockaddr is passed back to user space. The new function
places the sockaddr into the correct format depending on the
SCTP_I_WANT_MAPPED_V4_ADDR option.

Audit all places that touched v4mapped and either sanely construct
a v4 or v6 address then call addr_to_user, or drop the
unnecessary v4mapped check entirely.

Audit all places that call addr_to_user and verify they are on a sycall
return path.

Add a custom getname that formats the address properly.

Several bugs are addressed:
 - SCTP_I_WANT_MAPPED_V4_ADDR=0 often returned garbage for
   addresses to user space
 - The addr_len returned from recvmsg was not correct when
   returning AF_INET on a v6 socket
 - flowlabel and scope_id were not zerod when promoting
   a v4 to v6
 - Some syscalls like bind and connect behaved differently
   depending on v4mapped

Tested bind, getpeername, getsockname, connect, and recvmsg for proper
behaviour in v4mapped = 1 and 0 cases.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-31 21:49:06 -07:00
Daniel Borkmann 8f61059a96 net: sctp: improve timer slack calculation for transport HBs
RFC4960, section 8.3 says:

  On an idle destination address that is allowed to heartbeat,
  it is recommended that a HEARTBEAT chunk is sent once per RTO
  of that destination address plus the protocol parameter
  'HB.interval', with jittering of +/- 50% of the RTO value,
  and exponential backoff of the RTO if the previous HEARTBEAT
  is unanswered.

Currently, we calculate jitter via sctp_jitter() function first,
and then add its result to the current RTO for the new timeout:

  TMO = RTO + (RAND() % RTO) - (RTO / 2)
              `------------------------^-=> sctp_jitter()

Instead, we can just simplify all this by directly calculating:

  TMO = (RTO / 2) + (RAND() % RTO)

With the help of prandom_u32_max(), we don't need to open code
our own global PRNG, but can instead just make use of the per
CPU implementation of prandom with better quality numbers. Also,
we can now spare us the conditional for divide by zero check
since no div or mod operation needs to be used. Note that
prandom_u32_max() won't emit the same result as a mod operation,
but we really don't care here as we only want to have a random
number scaled into RTO interval.

Note, exponential RTO backoff is handeled elsewhere, namely in
sctp_do_8_2_transport_strike().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-02 18:44:07 -07:00
Daniel Borkmann e575235fc6 net: sctp: migrate most recently used transport to ktime
Be more precise in transport path selection and use ktime
helpers instead of jiffies to compare and pick the better
primary and secondary recently used transports. This also
avoids any side-effects during a possible roll-over, and
could lead to better path decision-making.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-11 12:23:17 -07:00
stephen hemminger 2045ceaed4 net: remove unnecessary return's
One of my pet coding style peeves is the practice of
adding extra return; at the end of function.
Kill several instances of this in network code.

I suppose some coccinelle wizardy could do this automatically.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 18:33:38 -05:00
David S. Miller 34f9f43710 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge 'net' into 'net-next' to get the AF_PACKET bug fix that
Daniel's direct transmit changes depend upon.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:20:14 -05:00
Jeff Kirsher 4b2f13a251 sctp: Fix FSF address in file headers
Several files refer to an old address for the Free Software Foundation
in the file header comment.  Resolve by replacing the address with
the URL <http://www.gnu.org/licenses/> so that we do not have to keep
updating the header comments anytime the address changes.

CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 12:37:56 -05:00
wangweidong 78ac814f12 sctp: disable max_burst when the max_burst is 0
As Michael pointed out that when max_burst is 0, it just disable
max_burst. It declared in rfc6458#section-8.1.24. so add the check
in sctp_transport_burst_limited, when it 0, just do nothing.

Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Suggested-by: Vlad Yasevich <vyasevich@gmail.com>
Suggested-by: Michael Tuexen <Michael.Tuexen@lurchi.franken.de>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 20:55:54 -05:00
David S. Miller 2ff1cf12c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-08-16 15:37:26 -07:00
Daniel Borkmann 771085d6bf net: sctp: sctp_transport_destroy{, _rcu}: fix potential pointer corruption
Probably this one is quite unlikely to be triggered, but it's more safe
to do the call_rcu() at the end after we have dropped the reference on
the asoc and freed sctp packet chunks. The reason why is because in
sctp_transport_destroy_rcu() the transport is being kfree()'d, and if
we're unlucky enough we could run into corrupted pointers. Probably
that's more of theoretical nature, but it's safer to have this simple fix.

Introduced by commit 8c98653f ("sctp: sctp_close: fix release of bindings
for deferred call_rcu's"). I also did the 8c98653f regression test and
it's fine that way.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-12 22:13:47 -07:00
Daniel Borkmann 477143e3fe net: sctp: trivial: update bug report in header comment
With the restructuring of the lksctp.org site, we only allow bug
reports through the SCTP mailing list linux-sctp@vger.kernel.org,
not via SF, as SF is only used for web hosting and nothing more.
While at it, also remove the obvious statement that bugs will be
fixed and incooperated into the kernel.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09 11:33:02 -07:00
Daniel Borkmann 91705c61b5 net: sctp: trivial: update mailing list address
The SCTP mailing list address to send patches or questions
to is linux-sctp@vger.kernel.org and not
lksctp-developers@lists.sourceforge.net anymore. Therefore,
update all occurences.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-24 17:53:38 -07:00
Daniel Borkmann bb33381d0c net: sctp: rework debugging framework to use pr_debug and friends
We should get rid of all own SCTP debug printk macros and use the ones
that the kernel offers anyway instead. This makes the code more readable
and conform to the kernel code, and offers all the features of dynamic
debbuging that pr_debug() et al has, such as only turning on/off portions
of debug messages at runtime through debugfs. The runtime cost of having
CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing,
is negligible [1]. If kernel debugging is completly turned off, then these
statements will also compile into "empty" functions.

While we're at it, we also need to change the Kconfig option as it /now/
only refers to the ifdef'ed code portions in outqueue.c that enable further
debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code
was enabled with this Kconfig option and has now been removed, we
transform those code parts into WARNs resp. where appropriate BUG_ONs so
that those bugs can be more easily detected as probably not many people
have SCTP debugging permanently turned on.

To turn on all SCTP debugging, the following steps are needed:

 # mount -t debugfs none /sys/kernel/debug
 # echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control

This can be done more fine-grained on a per file, per line basis and others
as described in [2].

 [1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf
 [2] Documentation/dynamic-debug-howto.txt

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01 23:22:13 -07:00
Daniel Borkmann 939cfa75a0 net: sctp: get rid of t_new macro for kzalloc
t_new rather obfuscates things where everyone else is using actual
function names instead of that macro, so replace it with kzalloc,
which is the function t_new wraps.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 17:08:04 -07:00
Daniel Borkmann 8fa5df6d21 net: sctp: sctp_transport: remove unused variable
sctp_transport's member 'malloced' is set to 1, never evaluated
and the structure is kfreed anyway. So just remove it.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17 14:13:02 -04:00
Ying Xue 25cc4ae913 net: remove redundant check for timer pending state before del_timer
As in del_timer() there has already placed a timer_pending() function
to check whether the timer to be deleted is pending or not, it's
unnecessary to check timer pending state again before del_timer() is
called.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04 13:26:49 -05:00
Daniel Borkmann 8c98653f05 sctp: sctp_close: fix release of bindings for deferred call_rcu's
It seems due to RCU usage, i.e. within SCTP's address binding list,
a, say, ``behavioral change'' was introduced which does actually
not conform to the RFC anymore. In particular consider the following
(fictional) scenario to demonstrate this:

  do:
    Two SOCK_SEQPACKET-style sockets are opened (S1, S2)
    S1 is bound to 127.0.0.1, port 1024 [server]
    S2 is bound to 127.0.0.1, port 1025 [client]
    listen(2) is invoked on S1
    From S2 we call one sendmsg(2) with msg.msg_name and
       msg.msg_namelen parameters set to the server's
       address
    S1, S2 are closed
    goto do

The first pass of this loop passes successful, while the second round
fails during binding of S1 (address still in use). What is happening?
In the first round, the initial handshake is being done, and, at the
time close(2) is called on S1, a non-graceful shutdown is performed via
ABORT since in S1's receive queue an unprocessed packet is present,
thus stating an error condition. This can be considered as a correct
behavior.

During close also all bound addresses are freed, thus nothing *must*
be active anymore. In reference to RFC2960:

  After checking the Verification Tag, the receiving endpoint shall
  remove the association from its record, and shall report the
  termination to its upper layer. (9.1 Abort of an Association)

Also, no half-open states are supported, thus after an ungraceful
shutdown, we leave nothing behind. However, this seems not to be
happening though. In a real-world scenario, this is exactly where
it breaks the lksctp-tools functional test suite, *for instance*:

  ./test_sockopt
  test_sockopt.c  1 PASS : getsockopt(SCTP_STATUS) on a socket with no assoc
  test_sockopt.c  2 PASS : getsockopt(SCTP_STATUS)
  test_sockopt.c  3 PASS : getsockopt(SCTP_STATUS) with invalid associd
  test_sockopt.c  4 PASS : getsockopt(SCTP_STATUS) with NULL associd
  test_sockopt.c  5 BROK : bind: Address already in use

The underlying problem is that sctp_endpoint_destroy() hasn't been
triggered yet while the next bind attempt is being done. It will be
triggered eventually (but too late) by sctp_transport_destroy_rcu()
after one RCU grace period:

  sctp_transport_destroy()
    sctp_transport_destroy_rcu() ----.
      sctp_association_put() [*]  <--+--> sctp_packet_free()
        sctp_association_destroy()          [...]
          sctp_endpoint_put()                 skb->destructor
            sctp_endpoint_destroy()             sctp_wfree()
              sctp_bind_addr_free()               sctp_association_put() [*]

Thus, we move out the condition with sctp_association_put() as well as
the sctp_packet_free() invocation and the issue can be solved. We also
better free the SCTP chunks first before putting the ref of the association.

With this patch, the example above (which simulates a similar scenario
as in the implementation of this test case) and therefore also the test
suite run successfully through. Tested by myself.

Cc: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04 13:22:33 -05:00
Thomas Graf 45122ca26c sctp: Add RCU protection to assoc->transport_addr_list
peer.transport_addr_list is currently only protected by sk_sock
which is inpractical to acquire for procfs dumping purposes.

This patch adds RCU protection allowing for the procfs readers to
enter RCU read-side critical sections.

Modification of the list continues to be serialized via sk_lock.

V2: Use list_del_rcu() in sctp_association_free() to be safe
    Skip transports marked dead when dumping for procfs

Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-07 14:15:04 -05:00
Michele Baldessari 196d675934 sctp: Add support to per-association statistics via a new SCTP_GET_ASSOC_STATS call
The current SCTP stack is lacking a mechanism to have per association
statistics. This is an implementation modeled after OpenSolaris'
SCTP_GET_ASSOC_STATS.

Userspace part will follow on lksctp if/when there is a general ACK on
this.
V4:
- Move ipackets++ before q->immediate.func() for consistency reasons
- Move sctp_max_rto() at the end of sctp_transport_update_rto() to avoid
  returning bogus RTO values
- return asoc->rto_min when max_obs_rto value has not changed

V3:
- Increase ictrlchunks in sctp_assoc_bh_rcv() as well
- Move ipackets++ to sctp_inq_push()
- return 0 when no rto updates took place since the last call

V2:
- Implement partial retrieval of stat struct to cope for future expansion
- Kill the rtxpackets counter as it cannot be precise anyway
- Rename outseqtsns to outofseqtsns to make it clearer that these are out
  of sequence unexpected TSNs
- Move asoc->ipackets++ under a lock to avoid potential miscounts
- Fold asoc->opackets++ into the already existing asoc check
- Kill unneeded (q->asoc) test when increasing rtxchunks
- Do not count octrlchunks if sending failed (SCTP_XMIT_OK != 0)
- Don't count SHUTDOWNs as SACKs
- Move SCTP_GET_ASSOC_STATS to the private space API
- Adjust the len check in sctp_getsockopt_assoc_stats() to allow for
  future struct growth
- Move association statistics in their own struct
- Update idupchunks when we send a SACK with dup TSNs
- return min_rto in max_rto when RTO has not changed. Also return the
  transport when max_rto last changed.

Signed-off: Michele Baldessari <michele@acksyn.org>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 13:32:15 -05:00
Schoch Christian 92d64c261e sctp: Error in calculation of RTTvar
The calculation of RTTVAR involves the subtraction of two unsigned
numbers which
may causes rollover and results in very high values of RTTVAR when RTT > SRTT.
With this patch it is possible to set RTOmin = 1 to get the minimum of RTO at
4 times the clock granularity.

Change Notes:

v2)
        *Replaced abs() by abs64() and long by __s64, changed patch
description.

Signed-off-by: Christian Schoch <e0326715@student.tuwien.ac.at>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Sridhar Samudrala <sri@us.ibm.com>
CC: Neil Horman <nhorman@tuxdriver.com>
CC: linux-sctp@vger.kernel.org
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-28 11:13:40 -05:00
Eric W. Biederman e1fc3b14f9 sctp: Make sysctl tunables per net
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-14 23:32:16 -07:00
Eric W. Biederman 89bf3450cb sctp: Push struct net down into sctp_transport_init
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-14 23:30:37 -07:00
David S. Miller 5e9965c15b Merge branch 'kill_rtcache'
The ipv4 routing cache is non-deterministic, performance wise, and is
subject to reasonably easy to launch denial of service attacks.

The routing cache works great for well behaved traffic, and the world
was a much friendlier place when the tradeoffs that led to the routing
cache's design were considered.

What it boils down to is that the performance of the routing cache is
a product of the traffic patterns seen by a system rather than being a
product of the contents of the routing tables.  The former of which is
controllable by external entitites.

Even for "well behaved" legitimate traffic, high volume sites can see
hit rates in the routing cache of only ~%10.

The general flow of this patch series is that first the routing cache
is removed.  We build a completely new rtable entry every lookup
request.

Next we make some simplifications due to the fact that removing the
routing cache causes several members of struct rtable to become no
longer necessary.

Then we need to make some amends such that we can legally cache
pre-constructed routes in the FIB nexthops.  Firstly, we need to
invalidate routes which are hit with nexthop exceptions.  Secondly we
have to change the semantics of rt->rt_gateway such that zero means
that the destination is on-link and non-zero otherwise.

Now that the preparations are ready, we start caching precomputed
routes in the FIB nexthops.  Output and input routes need different
kinds of care when determining if we can legally do such caching or
not.  The details are in the commit log messages for those changes.

The patch series then winds down with some more struct rtable
simplifications and other tidy ups that remove unnecessary overhead.

On a SPARC-T3 output route lookups are ~876 cycles.  Input route
lookups are ~1169 cycles with rpfilter disabled, and about ~1468
cycles with rpfilter enabled.

These measurements were taken with the kbench_mod test module in the
net_test_tools GIT tree:

git://git.kernel.org/pub/scm/linux/kernel/git/davem/net_test_tools.git

That GIT tree also includes a udpflood tester tool and stresses
route lookups on packet output.

For example, on the same SPARC-T3 system we can run:

	time ./udpflood -l 10000000 10.2.2.11

with routing cache:
real    1m21.955s       user    0m6.530s        sys     1m15.390s

without routing cache:
real    1m31.678s       user    0m6.520s        sys     1m25.140s

Performance undoubtedly can easily be improved further.

For example fib_table_lookup() performs a lot of excessive
computations with all the masking and shifting, some of it
conditionalized to deal with edge cases.

Also, Eric's no-ref optimization for input route lookups can be
re-instated for the FIB nexthop caching code path.  I would be really
pleased if someone would work on that.

In fact anyone suitable motivated can just fire up perf on the loading
of the test net_test_tools benchmark kernel module.  I spend much of
my time going:

bash# perf record insmod ./kbench_mod.ko dst=172.30.42.22 src=74.128.0.1 iif=2
bash# perf report

Thanks to helpful feedback from Joe Perches, Eric Dumazet, Ben
Hutchings, and others.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22 17:04:15 -07:00
Neil Horman 5aa93bcf66 sctp: Implement quick failover draft from tsvwg
I've seen several attempts recently made to do quick failover of sctp transports
by reducing various retransmit timers and counters.  While its possible to
implement a faster failover on multihomed sctp associations, its not
particularly robust, in that it can lead to unneeded retransmits, as well as
false connection failures due to intermittent latency on a network.

Instead, lets implement the new ietf quick failover draft found here:
http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05

This will let the sctp stack identify transports that have had a small number of
errors, and avoid using them quickly until their reliability can be
re-established.  I've tested this out on two virt guests connected via multiple
isolated virt networks and believe its in compliance with the above draft and
works well.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Sridhar Samudrala <sri@us.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
CC: joe@perches.com
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22 12:13:46 -07:00
David S. Miller f5b0a87436 net: Document dst->obsolete better.
Add a big comment explaining how the field works, and use defines
instead of magic constants for the values assigned to it.

Suggested by Joe Perches.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:31:21 -07:00
David S. Miller 6700c2709c net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()
This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17 03:29:28 -07:00
David S. Miller 02f3d4ce9e sctp: Adjust PMTU updates to accomodate route invalidation.
This adjusts the call to dst_ops->update_pmtu() so that we can
transparently handle the fact that, in the future, the dst itself can
be invalidated by the PMTU update (when we have non-host routes cached
in sockets).

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-16 03:57:14 -07:00
Neil Horman 4244854d22 sctp: be more restrictive in transport selection on bundled sacks
It was noticed recently that when we send data on a transport, its possible that
we might bundle a sack that arrived on a different transport.  While this isn't
a major problem, it does go against the SHOULD requirement in section 6.4 of RFC
2960:

 An endpoint SHOULD transmit reply chunks (e.g., SACK, HEARTBEAT ACK,
   etc.) to the same destination transport address from which it
   received the DATA or control chunk to which it is replying.  This
   rule should also be followed if the endpoint is bundling DATA chunks
   together with the reply chunk.

This patch seeks to correct that.  It restricts the bundling of sack operations
to only those transports which have moved the ctsn of the association forward
since the last sack.  By doing this we guarantee that we only bundle outbound
saks on a transport that has received a chunk since the last sack.  This brings
us into stricter compliance with the RFC.

Vlad had initially suggested that we strictly allow only sack bundling on the
transport that last moved the ctsn forward.  While this makes sense, I was
concerned that doing so prevented us from bundling in the case where we had
received chunks that moved the ctsn on multiple transports.  In those cases, the
RFC allows us to select any of the transports having received chunks to bundle
the sack on.  so I've modified the approach to allow for that, by adding a state
variable to each transport that tracks weather it has moved the ctsn since the
last sack.  This I think keeps our behavior (and performance), close enough to
our current profile that I think we can do this without a sysctl knob to
enable/disable it.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yaseivch <vyasevich@gmail.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
Reported-by: Michele Baldessari <michele@redhat.com>
Reported-by: sorin serban <sserban@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-30 22:44:35 -07:00
Nicolas Dichtel e0268868ba sctp: check cached dst before using it
dst_check() will take care of SA (and obsolete field), hence
IPsec rekeying scenario is taken into account.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Vlad Yaseivch <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-10 23:15:47 -04:00
Michio Honda ddc4bbee6e sctp: fasthandoff with ASCONF at mobile-node
Fast retransmission after changing the last address
with ASCONF negotiation

Signed-off-by: Michio Honda <micchie@sfc.wide.ad.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-08 15:11:29 -05:00
David S. Miller 8663c938ce sctp: Store a flowi in transports to provide persistent keying.
Several future simplifications are possible now because of this.

For example, the sctp_addr unions can simply refer directly to
the flowi information.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08 14:05:14 -07:00
Vlad Yasevich da0420bee2 sctp: clean up route lookup calls
Change the call to take the transport parameter and set the
cached 'dst' appropriately inside the get_dst() function calls.

This will allow us in the future  to clean up source address
storage as well.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-27 13:14:06 -07:00
Vlad Yasevich af1384703f sctp: remove useless arguments from get_saddr() call
There is no point in passing a destination address to
a get_saddr() call.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-27 13:14:06 -07:00
Vlad Yasevich 9914ae3ca7 sctp: cache the ipv6 source after route lookup
The ipv6 routing lookup does give us a source address,
but instead of filling it into the dst, it's stored in
the flowi.  We can use that instead of going through the
entire source address selection again.
Also the useless ->dst_saddr member of sctp_pf is removed.
And sctp_v6_dst_saddr() is removed, instead by introduce
sctp_v6_to_addr(), which can be reused to cleanup some dup
code.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-27 13:14:04 -07:00
Joe Perches 145ce502e4 net/sctp: Use pr_fmt and pr_<level>
Change SCTP_DEBUG_PRINTK and SCTP_DEBUG_PRINTK_IPADDR to
use do { print } while (0) guards.
Add SCTP_DEBUG_PRINTK_CONT to fix errors in log when
lines were continued.
Add #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
Add a missing newline in "Failed bind hash alloc"

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-26 14:11:48 -07:00
David S. Miller 6811d58fc1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	include/linux/if_link.h
2010-05-16 22:26:58 -07:00
Wei Yongjun 55fa0cfd7c sctp: delete active ICMP proto unreachable timer when free transport
transport may be free before ICMP proto unreachable timer expire, so
we should delete active ICMP proto unreachable timer when transport
is going away.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-16 00:46:22 -07:00
David S. Miller 278554bd65 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	Documentation/feature-removal-schedule.txt
	drivers/net/wireless/ath/ar9170/usb.c
	drivers/scsi/iscsi_tcp.c
	net/ipv4/ipmr.c
2010-05-12 00:05:35 -07:00
Vlad Yasevich 50b5d6ad63 sctp: Fix a race between ICMP protocol unreachable and connect()
ICMP protocol unreachable handling completely disregarded
the fact that the user may have locked the socket.  It proceeded
to destroy the association, even though the user may have
held the lock and had a ref on the association.  This resulted
in the following:

Attempt to release alive inet socket f6afcc00

=========================
[ BUG: held lock freed! ]
-------------------------
somenu/2672 is freeing memory f6afcc00-f6afcfff, with a lock still held
there!
 (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c
1 lock held by somenu/2672:
 #0:  (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c

stack backtrace:
Pid: 2672, comm: somenu Not tainted 2.6.32-telco #55
Call Trace:
 [<c1232266>] ? printk+0xf/0x11
 [<c1038553>] debug_check_no_locks_freed+0xce/0xff
 [<c10620b4>] kmem_cache_free+0x21/0x66
 [<c1185f25>] __sk_free+0x9d/0xab
 [<c1185f9c>] sk_free+0x1c/0x1e
 [<c1216e38>] sctp_association_put+0x32/0x89
 [<c1220865>] __sctp_connect+0x36d/0x3f4
 [<c122098a>] ? sctp_connect+0x13/0x4c
 [<c102d073>] ? autoremove_wake_function+0x0/0x33
 [<c12209a8>] sctp_connect+0x31/0x4c
 [<c11d1e80>] inet_dgram_connect+0x4b/0x55
 [<c11834fa>] sys_connect+0x54/0x71
 [<c103a3a2>] ? lock_release_non_nested+0x88/0x239
 [<c1054026>] ? might_fault+0x42/0x7c
 [<c1054026>] ? might_fault+0x42/0x7c
 [<c11847ab>] sys_socketcall+0x6d/0x178
 [<c10da994>] ? trace_hardirqs_on_thunk+0xc/0x10
 [<c1002959>] syscall_call+0x7/0xb

This was because the sctp_wait_for_connect() would aqcure the socket
lock and then proceed to release the last reference count on the
association, thus cause the fully destruction path to finish freeing
the socket.

The simplest solution is to start a very short timer in case the socket
is owned by user.  When the timer expires, we can do some verification
and be able to do the release properly.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-06 00:56:07 -07:00
Vlad Yasevich cf9b4812e1 sctp: fast recovery algorithm is per association.
SCTP fast recovery algorithm really applies per association
and impacts all transports.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2010-04-30 22:41:10 -04:00
Vlad Yasevich b2cf9b6bd9 sctp: update transport initializations
Right now, sctp transports are not fully initialized and when
adding any new fields, they have to be explicitely initialized.
This is prone to mistakes.  So we switch to calling kzalloc()
which makes things much simpler.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2010-04-30 22:41:10 -04:00
Vlad Yasevich d9efc2231b sctp: Do not force T3 timer on fast retransmissions.
We don't need to force the T3 timer any more and it's
actually wrong to do as it causes too long of a delay.
The timer will be started if one is not running, but if
one is running, we leave it alone.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2010-04-30 22:41:09 -04:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
David S. Miller 9b963e5d0e Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/ieee802154/fakehard.c
	drivers/net/e1000e/ich8lan.c
	drivers/net/e1000e/phy.c
	drivers/net/netxen/netxen_nic_init.c
	drivers/net/wireless/ath/ath9k/main.c
2009-11-29 00:57:15 -08:00
Andrei Pelinescu-Onciul 5fdd4baef6 sctp: on T3_RTX retransmit all the in-flight chunks
When retransmitting due to T3 timeout, retransmit all the
in-flight chunks for the corresponding  transport/path, including
chunks sent less then 1 rto ago.
This is the correct behaviour according to rfc4960 section 6.3.3
E3 and
"Note: Any DATA chunks that were sent to the address for which the
 T3-rtx timer expired but did not fit in one MTU (rule E3 above)
 should be marked for retransmission and sent as soon as cwnd
 allows (normally, when a SACK arrives). ".

This fixes problems when more then one path is present and the T3
retransmission of the first chunk that timeouts stops the T3 timer
for the initial active path, leaving all the other in-flight
chunks waiting forever or until a new chunk is transmitted on the
same path and timeouts (and this will happen only if the cwnd
allows sending new chunks, but since cwnd was dropped to MTU by
the timeout => it will wait until the first heartbeat).

Example: 10 packets in flight, sent at 0.1 s intervals on the
primary path. The primary path is down and the first packet
timeouts. The first packet is retransmitted on another path, the
T3 timer for the primary path is stopped and cwnd is set to MTU.
All the other 9 in-flight packets will not be retransmitted
(unless more new packets are sent on the primary path which depend
on cwnd allowing it, and even in this case the 9 packets will be
retransmitted only after a new packet timeouts which even in the
best case would be more then RTO).

This commit reverts d0ce92910b and
also removes the now unused transport->last_rto, introduced in
 b6157d8e03.

p.s  The problem is not only when multiple paths are there.  It
can happen in a single homed environment.  If the application
stops sending data, it possible to have a hung association.

Signed-off-by: Andrei Pelinescu-Onciul <andrei@iptel.org>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-29 00:14:02 -08:00
Vlad Yasevich 46d5a80855 sctp: Update max.burst implementation
Current implementation of max.burst ends up limiting new
data during cwnd decay period.  The decay is happening becuase
the connection is idle and we are allowed to fill the congestion
window.  The point of max.burst is to limit micro-bursts in response
to large acks.  This still happens, as max.burst is still applied
to each transmit opportunity.  It will also apply if a very large
send is made (greater then allowed by burst).

Tested-by: Florian Niederbacher <florian.niederbacher@student.uibk.ac.at>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2009-11-23 15:54:00 -05:00
Vlad Yasevich 245cba7e55 sctp: Remove useless last_time_used variable
The transport last_time_used variable is rather useless.
It was only used when determining if CWND needs to be updated
due to idle transport.  However, idle transport detection was
based on a Heartbeat timer and last_time_used was not incremented
when sending Heartbeats.  As a result the check for cwnd reduction
was always true.  We can get rid of the variable and just base
our cwnd manipulation on the HB timer (like the code comment sais).
We also have to call into the cwnd manipulation function regardless
of whether HBs are enabled or not.  That way we will detect idle
transports if the user has disabled Heartbeats.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2009-11-23 15:53:58 -05:00
Vlad Yasevich a78102e74e sctp: Set socket source address when additing first transport
Recent commits
	sctp: Get rid of an extra routing lookup when adding a transport
and
	sctp: Set source addresses on the association before adding transports

changed when routes are added to the sctp transports.  As such,
we didn't set the socket source address correctly when adding the first
transport.  The first transport is always the primary/active one, so
when adding it, set the socket source address.  This was causing
regression failures in SCTP tests.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-13 19:56:52 -08:00
Vlad Yasevich 33ce828131 sctp: Clear fast_recovery on the transport when T3 timer expires.
If T3 timer expires, we are retransmitting data due to timeout any
any fast recovery is null and void.  We can clear the fast recovery
flag.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
2009-09-04 18:20:58 -04:00
Wei Yongjun f61f6f82c9 sctp: use time_before or time_after for comparing jiffies
The functions time_before or time_after are more robust
for comparing jiffies against other values.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-02 22:49:18 -08:00
Vlad Yasevich faee47cdbf sctp: Fix the RTO-doubling on idle-link heartbeats
SCTP incorrectly doubles rto ever time a Hearbeat chunk
is generated.   However RFC 4960 states:

   On an idle destination address that is allowed to heartbeat, it is
   recommended that a HEARTBEAT chunk is sent once per RTO of that
   destination address plus the protocol parameter 'HB.interval', with
   jittering of +/- 50% of the RTO value, and exponential backoff of the
   RTO if the previous HEARTBEAT is unanswered.

Essentially, of if the heartbean is unacknowledged, do we double the RTO.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-16 00:03:10 -08:00