was limited to one segment under the faulty assumption of a retransmit.
Due to this the opportunity to initialize the increased congestion window
according to RFC3390 was missed.
Support for RFC3465 introduced in r187289 uncovered the bug as the ACK
to SYN/ACK no longer caused snd_cwnd increase by MSS (actually, this
increase shouldn't happen as it's explicitly forbidden by RFC3390, but
it's another issue). Snd_cwnd remains really small (1*MSS + 1) and this
causes really bad interaction with delayed acks on other side.
The variable name sc_rxmits is a bit misleading as it counts all transmits,
not just retransmits.
Submitted by: Maxim Dounin <mdounin-at-mdounin-dot-ru>
MFC after: 10 days
PR SCTP FWD-TSN's would not be sent and thus
cause a stalled connection. Also the rwnd
Calculation was also off on the receiver side for
PR-SCTP.
MFC after: 1 month
retransmission queue to validate the retran count, we
need to include the chunks in the control send queue
too. Otherwise the count will not match and you will get
the invarient warning if invarients are on.
MFC after: 2 weeks
a separate inline function. This further reduces duplicate code that didn't
have a good reason to stay as it was.
- Reorder the malloc of a pkt_node struct in the hook functions such that it
only occurs if we managed to find a usable tcpcb associated with the packet.
- Make the inp_locally_locked variable's type consistent with the prototype of
siftr_siftdata().
Sponsored by: FreeBSD Foundation
large number of packets queued to a crashing process.
In a specific case you may get 2 ABORT's back (from
say two packets in flight). If the aborts happened to
be processed at the same time its possible to have
one free the association while the other is trying
to report all the outbound packets. When this occured
it could lead to a crash.
MFC after: 3 days
FreeBSD. SIFTR logs a range of statistics on active TCP connections to a log
file, providing the ability to make highly granular measurements of TCP
connection state. The tool is aimed at system administrators, developers and
researchers alike. Please take it for a spin and test it out - the man page
should have all the information required to get you going.
Many thanks go to the Cisco University Research Program Fund at Community
Foundation Silicon Valley and the FreeBSD Foundation. Their support of our work
at the Centre for Advanced Internet Architectures, Swinburne University of
Technology is greatly appreciated.
Sponsored by: Cisco URP, FreeBSD Foundation
Reviewed by: dwmalone, gnn, rpaulo
Tested by: Many on freebsd-current@ and elsewhere over the years
MFC after: 1 month
a read-lock is being called to check the vtag-timewait cache.
Then in two cases (where a vtag is bad i.e. in the time-wait
state) the write-unlock is called NOT the read-unlock. Under
conditions where lots of associations are coming and going
this will cause the system to panic at some point.
MFC after: 3 days
"match" processing at the end of inner loop would look ahead into the next
rule, which is incorrect. Particularly, in the case when the next rule
started with F_NOT opcode it was skipped blindly.
To fix this, exit the inner loop with the continue operator forcibly and
explicitly.
PR: kern/147798
wrong side into account.
* sctp_findassociation_ep_addr() must check the local address if available.
This fixes a bug where ABORT chunks were accepted even in the case where
the local was not owned by the endpoint.
Thanks to brucec for pointing out a bug in my first version of the fix.
MFC after: 3 days
to using an uninitialized variable.
* Fix a bug where a NULL pointer was dereferenced when interfaces
come and go at a high rate.
* Fix a bug where inps where not deregistered from iterators.
* Fix a race condition in freeing an association.
* Fix a refcount problem related to the iterator.
Each of the above bug results in a panic. It shows up when
interfaces come and go at a high rate.
Obtained from: rrs (partly)
MFC after: 3 days
a) There was a case where a ICMP message could cause
us to return leaving a stuck lock on an stcb.
b) The iterator needed some tweaks to fix its lock
ordering.
c) The ITERATOR_LOCK is no longer needed in the freeing
of a stcb. Now that the timer based one is gone we don't
have a multiple resume situation. Add to that that there
was somewhere a path out of the freeing of an assoc that
did NOT release the iterator_lock.. it was time to clean
this old code up and in the process fix the lock bug.
MFC after: 1 week
sctp_inpcb:
1) Make sure not to remove the flag on the PCB until
after the close() caller is back in control with the
lock. Otherwise a quickly freeing assoc could kill the
inpcb and cause a panic.
2) Make sure all calls to log_closing have not released
the locks before calling the log function, we don't
want the logging function to crash us due to a freed
inpcb.
3) Make sure that when we get to the end, we release all
locks (after removing them from view) and as long as
we are NOT the inp-kill timer removing the inp, call
the callout_drain() function so a racing timer won't
later call in and cause a racing crash.
MFC after: 1 week
1) Only use both mapping arrays when NR sack is off. This
way we can hold off moving the cumack (not the best but
workable) when NR-sack is on.
2) We must make sure to just return on the move of the
bit to the NR array if the cum-ack as already went
past the TSN. This prevents marking a bit behind the
array and hitting the invariant code that panic's us.
MFC after: 1 week
We were only paying attention to the nr-mapping-array. Which
seems to make sense on the surface, by definition things
up to the cum-ack should be deliverable thus in the nr-mapping-array.
However (there is always a gotcha) thats not true when it
comes to large messages. The stack may hold the message
while re-assembling it not not deliver it based on several
thresholds. If that happens (which it would for smaller
large messages) then the cum-ack is figured wrong. We
now properly use both arrays in the cum-ack calculation.
MFC after: 1 week.
the timer. This is done by considering the locks
we will destroy and if they are contended we consider
it the same as a reference count being up. Fixing this
appears to cleanup another crash that was appearing with
all the timers where the socket buf lock got corrupted.
2) Fix the sysctl code to take a lot more care when looking
at INP's that are in the GONE or ALLGONE state.
MFC after: 1 week
of apitesters.. Basically we end up with attempting
to destroy a lock thats contended on. A cookie echo
arrives at the same time that the close is happening.
The close gets the lock but the cookie echo has already
passed the check for the gone flag and is then locked
waiting on the create lock.. when we go to destroy it
bam. For now we do the timer destroy for all calls
to close.. We can probably optimize this later so that
we check whats being contended on and if there is contention
then do the timer thing. but this is probably safest since
the inp has been removed from all lists and references and
only the timer can find it.. once the locks are released all
other places will instantly see the GONE flag and bail (thats
what the change in sctp_input is one place that was lacking
the bail code).
MFC after: 1 week
held by checking the create and inp locks as well.
2) Fix a bug in that when a socket is closed an INIT-ACK
is returned, we do NOT unlock the locked_tcb unless its
different (an unlikely scenario). If we blindly unlock as
we were doing before we can end up unlocking the actual
stcb thats about to be sent down to the free function which
requires the lock be held.
MFC after: 1 week
was setup to do an abortive close an association that was
in the accept_queue could get stuck and never freed. Now
we properly start the kill timer on the socket and turn
off the flag (same thing we do for the graceful close method).
MFC after: 1 week
1) Fix the alignment of a comment.
2) Fix a BUG where we were NOT paying attention
to the RESEND marking on retransmitting control
chunks.. and worse we were not decrementing the
retran count that could cause us to loop forever.
3) Add in the valdiate_no_lock function on invariants
so that we will really check all ways out to be sure
a lock does not slip out locked.
MFC after: 1 week.
1) Makes it so that the INVARIANT function validate nolocks is
available anywhere.
2) Fixes a BUG where a close has been done on a collision socket
and the cookie processing would return leaving a lock held.
MFC after: 1 week
code base. We now properly have ONE thread
that services all VNET's. Also we purge out
the old timer based iterator code which had
multiple LOR's and other issues.
MFC after: 3 days
- Make sure that when you kick the streams you add correctly
using a 16 bit unsigned.
- Make sure when sending out you allow FWD-TSN to skip over
and list the ACKED chunks in the stream/seq list (so the
rcv will kick the stream)
MFC after: 3 days
