kernel.git/net/sctp/output.c, branch linux-4.10.y

sctp: clean up sctp_packet_transmit

2016-11-02T19:03:13Z

After adding sctp gso, sctp_packet_transmit is a quite big function now. This patch is to extract the codes for packing packet to sctp_packet_pack from sctp_packet_transmit, and add some comments, simplify the err path by freeing auth chunk when freeing packet chunk_list in out path and freeing head skb early if it fails to pack packet. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-10-30T16:42:58Z

Mostly simple overlapping changes. For example, David Ahern's adjacency list revamp in 'net-next' conflicted with an adjacency list traversal bug fix in 'net'. Signed-off-by: David S. Miller

sctp: fix the panic caused by route update

2016-10-26T21:32:19Z

Commit 7303a1475008 ("sctp: identify chunks that need to be fragmented at IP level") made the chunk be fragmented at IP level in the next round if it's size exceed PMTU. But there still is another case, PMTU can be updated if transport's dst expires and transport's pmtu_pending is set in sctp_packet_transmit. If the new PMTU is less than the chunk, the same issue with that commit can be triggered. So we should drop this packet and let it retransmit in another round where it would be fragmented at IP level. This patch is to fix it by checking the chunk size after PMTU may be updated and dropping this packet if it's size exceed PMTU. Fixes: 90017accff61 ("sctp: Add GSO support") Signed-off-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller

sctp: remove the old ttl expires policy

2016-10-13T13:44:14Z

The prsctp polices include ttl expires policy already, we should remove the old ttl expires codes, and just adjust the new polices' codes to be compatible with the old one for users. This patch is to remove all the old expires codes, and if prsctp polices are not set, it will still set msg's expires_at and check the expires in sctp_check_abandoned. Note that asoc->prsctp_enable is set by default, so users can't feel any difference even if they use the old expires api in userspace. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: reuse sent_count to avoid retransmitted chunks for RTT measurements

2016-10-13T13:44:13Z

Now sctp uses chunk->resent to record if a chunk is retransmitted, for RTT measurements with retransmitted DATA chunks. chunk->sent_count was introduced to record how many times one chunk has been sent for prsctp RTX policy before. We actually can know if one chunk is retransmitted by checking chunk->sent_count is greater than 1. This patch is to remove resent from sctp_chunk and reuse sent_count to avoid retransmitted chunks for RTT measurements. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: rename WORD_TRUNC/ROUND macros

2016-09-22T07:13:26Z

To something more meaningful these days, specially because this is working on packet headers or lengths and which are not tied to any CPU arch but to the protocol itself. So, WORD_TRUNC becomes SCTP_TRUNC4 and WORD_ROUND becomes SCTP_PAD4. Reported-by: David Laight Reported-by: David Miller Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: not return ENOMEM err back in sctp_packet_transmit

2016-09-19T02:02:33Z

As David and Marcelo's suggestion, ENOMEM err shouldn't return back to user in transmit path. Instead, sctp's retransmit would take care of the chunks that fail to send because of ENOMEM. This patch is only to do some release job when alloc_skb fails, not to return ENOMEM back any more. Besides, it also cleans up sctp_packet_transmit's err path, and fixes some issues in err path: - It didn't free the head skb in nomem: path. - No need to check nskb in no_route: path. - It should goto err: path if alloc_skb fails for head. - Not all the NOMEMs should free nskb. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: save transmit error to sk_err in sctp_outq_flush

2016-09-19T02:02:32Z

Every time when sctp calls sctp_outq_flush, it sends out the chunks of control queue, retransmit queue and data queue. Even if some trunks are failed to transmit, it still has to flush all the transports, as it's the only chance to clean that transmit_list. So the latest transmit error here should be returned back. This transmit error is an internal error of sctp stack. I checked all the places where it uses the transmit error (the return value of sctp_outq_flush), most of them are actually just save it to sk_err. Except for sctp_assoc/endpoint_bh_rcv, they will drop the chunk if it's failed to send a REPLY, which is actually incorrect, as we can't be sure the error that sctp_outq_flush returns is from sending that REPLY. So it's meaningless for sctp_outq_flush to return error back. This patch is to save transmit error to sk_err in sctp_outq_flush, the new error can update the old value. Eventually, sctp_wait_for_* would check for it. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: identify chunks that need to be fragmented at IP level

2016-09-10T02:18:33Z

Previously, without GSO, it was easy to identify it: if the chunk didn't fit and there was no data chunk in the packet yet, we could fragment at IP level. So if there was an auth chunk and we were bundling a big data chunk, it would fragment regardless of the size of the auth chunk. This also works for the context of PMTU reductions. But with GSO, we cannot distinguish such PMTU events anymore, as the packet is allowed to exceed PMTU. So we need another check: to ensure that the chunk that we are adding, actually fits the current PMTU. If it doesn't, trigger a flush and let it be fragmented at IP level in the next round. Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: fix the issue sctp requeue auth chunk incorrectly

2016-07-31T05:06:22Z

sctp needs to queue auth chunk back when we know that we are going to generate another segment. But commit f1533cce60d1 ("sctp: fix panic when sending auth chunks") requeues the last chunk processed which is probably not the auth chunk. It causes panic when calculating the MAC in sctp_auth_calculate_hmac(), as the incorrect offset of the auth chunk in skb->data. This fix is to requeue it by using packet->auth. Fixes: f1533cce60d1 ("sctp: fix panic when sending auth chunks") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller