kernel.git/net/sctp/outqueue.c, branch linux-3.11.y

net: sctp: confirm route during forward progress

2013-07-09T19:49:56Z

This fix has been proposed originally by Vlad Yasevich. He says: When SCTP makes forward progress (receives a SACK that acks new chunks, renegs, or answeres 0-window probes) or when HB-ACK arrives, mark the route as confirmed so we don't unnecessarily send NUD probes. Having a simple SCTP client/server that exchange data chunks every 1sec, without this patch ARP requests are sent periodically every 40-60sec. With this fix applied, an ARP request is only done once right at the "session" beginning. Also, when clearing the related ARP cache entry manually during the session, a new request is correctly done. I have only "backported" this to net-next and tested that it works, so full credit goes to Vlad. Signed-off-by: Vlad Yasevich Signed-off-by: Daniel Borkmann Acked-by: Neil Horman Signed-off-by: David S. Miller

net: sctp: get rid of SCTP_DBG_TSNS entirely

2013-07-02T07:08:03Z

After having reworked the debugging framework, Neil and Vlad agreed to get rid of the leftover SCTP_DBG_TSNS code for a couple of reasons: We can use systemtap scripts to investigate these things, we now have pr_debug() helpers that make life easier, and if we really need anything else besides those tools, we will be forced to come up with something better than we have there. Therefore, get rid of this ifdef debugging code entirely for now. Signed-off-by: Daniel Borkmann CC: Vlad Yasevich CC: Neil Horman Acked-by: Neil Horman Acked-by: Vlad Yasevich Signed-off-by: David S. Miller

net: sctp: rework debugging framework to use pr_debug and friends

2013-07-02T06:22:13Z

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 Signed-off-by: David S. Miller

sctp: fully initialize sctp_outq in sctp_outq_init

2013-06-14T01:05:24Z

In commit 2f94aabd9f6c925d77aecb3ff020f1cc12ed8f86 (refactor sctp_outq_teardown to insure proper re-initalization) we modified sctp_outq_teardown to use sctp_outq_init to fully re-initalize the outq structure. Steve West recently asked me why I removed the q->error = 0 initalization from sctp_outq_teardown. I did so because I was operating under the impression that sctp_outq_init would properly initalize that value for us, but it doesn't. sctp_outq_init operates under the assumption that the outq struct is all 0's (as it is when called from sctp_association_init), but using it in __sctp_outq_teardown violates that assumption. We should do a memset in sctp_outq_init to ensure that the entire structure is in a known state there instead. Signed-off-by: Neil Horman Reported-by: "West, Steve (NSN - US/Fort Worth)" CC: Vlad Yasevich CC: netdev@vger.kernel.org CC: davem@davemloft.net Acked-by: Vlad Yasevich Signed-off-by: David S. Miller

net: sctp: outqueue: simplify sctp_outq_uncork function

2013-04-17T18:13:02Z

Just a minor edit to simplify the function. No need for this error variable here. Signed-off-by: Daniel Borkmann Acked-by: Neil Horman Signed-off-by: David S. Miller

net: sctp: sctp_outq: remove 'malloced' from its struct

2013-04-17T18:13:02Z

sctp_outq is embedded into sctp_association, and thus never kmalloced in any way. Also, malloced is always 0, thus kfree() is never called. Therefore, remove that dead piece of code. Signed-off-by: Daniel Borkmann Acked-by: Neil Horman Signed-off-by: David S. Miller

net: remove redundant check for timer pending state before del_timer

2013-02-04T18:26:49Z

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 Cc: Eric Dumazet Signed-off-by: David S. Miller

sctp: refactor sctp_outq_teardown to insure proper re-initalization

2013-01-17T23:39:56Z

Jamie Parsons reported a problem recently, in which the re-initalization of an association (The duplicate init case), resulted in a loss of receive window space. He tracked down the root cause to sctp_outq_teardown, which discarded all the data on an outq during a re-initalization of the corresponding association, but never reset the outq->outstanding_data field to zero. I wrote, and he tested this fix, which does a proper full re-initalization of the outq, fixing this problem, and hopefully future proofing us from simmilar issues down the road. Signed-off-by: Neil Horman Reported-by: Jamie Parsons Tested-by: Jamie Parsons CC: Jamie Parsons CC: Vlad Yasevich CC: "David S. Miller" CC: netdev@vger.kernel.org Acked-by: Vlad Yasevich Signed-off-by: David S. Miller

sctp: Add support to per-association statistics via a new SCTP_GET_ASSOC_STATS call

2012-12-03T18:32:15Z

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 Acked-by: Vlad Yasevich Signed-off-by: David S. Miller

sctp: check src addr when processing SACK to update transport state

2012-10-04T19:53:48Z

Suppose we have an SCTP connection with two paths. After connection is established, path1 is not available, thus this path is marked as inactive. Then traffic goes through path2, but for some reasons packets are delayed (after rto.max). Because packets are delayed, the retransmit mechanism will switch again to path1. At this time, we receive a delayed SACK from path2. When we update the state of the path in sctp_check_transmitted(), we do not take into account the source address of the SACK, hence we update the wrong path. Signed-off-by: Nicolas Dichtel Acked-by: Vlad Yasevich Signed-off-by: David S. Miller