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>
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>
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>
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>
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>
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>
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>
valgrind reports uninizialized memory accesses when running
sctp inside the network simulation cradle simulator:
Conditional jump or move depends on uninitialised value(s)
at 0x570E34A: sctp_assoc_sync_pmtu (associola.c:1324)
by 0x57427DA: sctp_packet_transmit (output.c:403)
by 0x5710EFF: sctp_outq_flush (outqueue.c:824)
by 0x5710B88: sctp_outq_uncork (outqueue.c:701)
by 0x5745262: sctp_cmd_interpreter (sm_sideeffect.c:1548)
by 0x57444B7: sctp_side_effects (sm_sideeffect.c:976)
by 0x5744460: sctp_do_sm (sm_sideeffect.c:945)
by 0x572157D: sctp_primitive_ASSOCIATE (primitive.c:94)
by 0x5725C04: __sctp_connect (socket.c:1094)
by 0x57297DC: sctp_connect (socket.c:3297)
Conditional jump or move depends on uninitialised value(s)
at 0x575D3A5: mod_timer (timer.c:630)
by 0x5752B78: sctp_cmd_hb_timers_start (sm_sideeffect.c:555)
by 0x5754133: sctp_cmd_interpreter (sm_sideeffect.c:1448)
by 0x5753607: sctp_side_effects (sm_sideeffect.c:976)
by 0x57535B0: sctp_do_sm (sm_sideeffect.c:945)
by 0x571E9AE: sctp_endpoint_bh_rcv (endpointola.c:474)
by 0x573347F: sctp_inq_push (inqueue.c:104)
by 0x572EF93: sctp_rcv (input.c:256)
by 0x5689623: ip_local_deliver_finish (ip_input.c:230)
by 0x5689759: ip_local_deliver (ip_input.c:268)
by 0x5689CAC: ip_rcv_finish (dst.h:246)
#1 is due to "if (t->pmtu_pending)".
8a4794914f "[SCTP] Flag a pmtu change request"
suggests it should be initialized to 0.
#2 is the heartbeat timer 'expires' value, which is uninizialised, but
test by mod_timer().
T3_rtx_timer seems to be affected by the same problem, so initialize it, too.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we are trying to fast retransmit the lowest outstanding TSN, we
need to restart the T3-RTX timer, so that subsequent timeouts will
correctly tag all the packets necessary for retransmissions.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Tested-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correctly keep track of Fast Recovery state and do not reduce
congestion window multiple times during sucht state.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Tested-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 7cbca67c07 ("[IPV6]: Support
Source Address Selection API (RFC5014)") introduced NULL dereference
of asoc to sctp_v6_get_saddr in net/sctp/ipv6.c.
Pointed out by Johann Felix Soden <johfel@users.sourceforge.net>.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I was notified by Randy Stewart that lksctp claims to be
"the reference implementation". First of all, "the
refrence implementation" was the original implementation
of SCTP in usersapce written ty Randy and a few others.
Second, after looking at the definiton of 'reference implementation',
we don't really meet the requirements.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Many-many code in the kernel initialized the timer->function
and timer->data together with calling init_timer(timer). There
is already a helper for this. Use it for networking code.
The patch is HUGE, but makes the code 130 lines shorter
(98 insertions(+), 228 deletions(-)).
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit d0ce92910b broke several retransmit
cases including fast retransmit. The reason is that we should
only delay by rto while doing retranmists as a result of a timeout.
Retransmit as a result of path mtu discover, fast retransmit, or
other evernts that should trigger immidiate retransmissions got broken.
Also, since rto is doubled prior to marking of packets elegable for
retransmission, we never marked correct chunks anyway.
The fix is provide a reason for a given retransmission so that we
can mark chunks appropriately and to save the old rto value to do
comparisons against.
All regressions tests passed with this code.
Spotted by Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Right now, when we receive a mtu estimate smaller then minim
threshold in the ICMP message, we disable the path mtu discovery
on the transport. This leads to the never increasing sctp fragmentation
point even when the real path mtu has increased.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Introduce new function sctp_transport_update_pmtu that updates
the transports and destination caches view of the path mtu.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
Spring cleaning time...
There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals. Most commonly is a
bogus semicolon after: switch() { }
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reset ssthresh to the correct value (peer's a_rwnd) when restarting
association.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the association has been restarted, we need to reset the
transport congestion variables as well as accumulated error
counts and CACC variables. If we do not, the association
will use the wrong values and may terminate prematurely.
This was found with a scenario where the peer restarted
the association when lksctp was in the last HB timeout for
its association. The restart happened, but the error counts
have not been reset and when the timeout occurred, a newly
restarted association was terminated due to excessive
retransmits.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SCTP sysctl entries are displayed in milliseconds, but stored
internally in jiffies. This results in multiple levels of msecs to
jiffies conversion and as a result produces a truncation error. This
patch makes things consistent in that we store and display defaults
in milliseconds and only convert once for use by association.
This patch also adds some sane min/max values so that we don't go off
the deep end.
Signed-off-by: Vladislav Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements Path Initialization procedure as described in
Sec 2.36 of RFC4460.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change all the structure members that hold jiffies to be of type
unsigned long. This also corrects bad sysctl formating on 64 bit
architectures.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
This patch adds support to set/get heartbeat interval, maximum number of
retransmissions, pathmtu, sackdelay time for a particular transport/
association/socket as per the latest SCTP sockets api draft11.
Signed-off-by: Frank Filz <ffilz@us.ibm.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
an ipv4 socket.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- added typedef unsigned int __nocast gfp_t;
- replaced __nocast uses for gfp flags with gfp_t - it gives exactly
the same warnings as far as sparse is concerned, doesn't change
generated code (from gcc point of view we replaced unsigned int with
typedef) and documents what's going on far better.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implements sctp_connectx() as defined in the SCTP sockets API draft by
tunneling the request through a setsockopt().
Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
David S. Miller