kernel/net/sctp/input.c, branch linux-5.1.y

sctp: add sock_reuseport for the sock in __sctp_hash_endpoint

2018-11-12T17:09:51Z

This is a part of sk_reuseport support for sctp. It defines a helper sctp_bind_addrs_check() to check if the bind_addrs in two socks are matched. It will add sock_reuseport if they are completely matched, and return err if they are partly matched, and alloc sock_reuseport if all socks are not matched at all. It will work until sk_reuseport support is added in sctp_get_port_local() in the next patch. v1->v2: - use 'laddr->valid && laddr2->valid' check instead as Marcelo pointed in sctp_bind_addrs_check(). Acked-by: Neil Horman Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: do reuseport_select_sock in __sctp_rcv_lookup_endpoint

2018-11-12T17:09:51Z

This is a part of sk_reuseport support for sctp, and it selects a sock by the hashkey of lport, paddr and dport by default. It will work until sk_reuseport support is added in sctp_get_port_local() in the next patch. v1->v2: - define lport as __be16 instead of __be32 as Marcelo pointed in __sctp_rcv_lookup_endpoint(). Acked-by: Neil Horman Signed-off-by: Xin Long Signed-off-by: David S. Miller

net: Convert protocol error handlers from void to int

2018-11-09T01:13:08Z

We'll need this to handle ICMP errors for tunnels without a sending socket (i.e. FoU and GUE). There, we might have to look up different types of IP tunnels, registered as network protocols, before we get a match, so we want this for the error handlers of IPPROTO_IPIP and IPPROTO_IPV6 in both inet_protos and inet6_protos. These error codes will be used in the next patch. For consistency, return sensible error codes in protocol error handlers whenever handlers can't handle errors because, even if valid, they don't match a protocol or any of its states. This has no effect on existing error handling paths. Signed-off-by: Stefano Brivio Reviewed-by: Sabrina Dubroca Signed-off-by: David S. Miller

sctp: use the pmtu from the icmp packet to update transport pathmtu

2018-10-16T05:54:20Z

Other than asoc pmtu sync from all transports, sctp_assoc_sync_pmtu is also processing transport pmtu_pending by icmp packets. But it's meaningless to use sctp_dst_mtu(t->dst) as new pmtu for a transport. The right pmtu value should come from the icmp packet, and it would be saved into transport->mtu_info in this patch and used later when the pmtu sync happens in sctp_sendmsg_to_asoc or sctp_packet_config. Besides, without this patch, as pmtu can only be updated correctly when receiving a icmp packet and no place is holding sock lock, it will take long time if the sock is busy with sending packets. Note that it doesn't process transport->mtu_info in .release_cb(), as there is no enough information for pmtu update, like for which asoc or transport. It is not worth traversing all asocs to check pmtu_pending. So unlike tcp, sctp does this in tx path, for which mtu_info needs to be atomic_t. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

rhashtable: split rhashtable.h

2018-06-22T04:43:27Z

Due to the use of rhashtables in net namespaces, rhashtable.h is included in lots of the kernel, so a small changes can required a large recompilation. This makes development painful. This patch splits out rhashtable-types.h which just includes the major type declarations, and does not include (non-trivial) inline code. rhashtable.h is no longer included by anything in the include/ directory. Common include files only include rhashtable-types.h so a large recompilation is only triggered when that changes. Acked-by: Herbert Xu Signed-off-by: NeilBrown Signed-off-by: David S. Miller

sctp: remove unnecessary asoc in sctp_has_association

2018-03-27T14:22:11Z

After Commit dae399d7fdee ("sctp: hold transport instead of assoc when lookup assoc in rx path"), it put transport instead of asoc in sctp_has_association. Variable 'asoc' is not used any more. So this patch is to remove it, while at it, it also changes the return type of sctp_has_association to bool, and does the same for it's caller sctp_endpoint_is_peeled_off. Signed-off-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller

net: use skb_is_gso_sctp() instead of open-coding

2018-03-09T16:41:47Z

As well as the basic conversion, I noticed that a lot of the SCTP code checks gso_type without first checking skb_is_gso() so I have added that where appropriate. Also, document the helper. Cc: Daniel Borkmann Cc: Marcelo Ricardo Leitner Signed-off-by: Daniel Axtens Signed-off-by: David S. Miller

sctp: do not pr_err for the duplicated node in transport rhlist

2018-02-12T16:39:32Z

The pr_err in sctp_hash_transport was supposed to report a sctp bug for using rhashtable/rhlist. The err '-EEXIST' introduced in Commit cd2b70875058 ("sctp: check duplicate node before inserting a new transport") doesn't belong to that case. So just return -EEXIST back without pr_err any kmsg. Fixes: cd2b70875058 ("sctp: check duplicate node before inserting a new transport") Reported-by: Wei Chen Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller

sctp: fix the handling of ICMP Frag Needed for too small MTUs

2018-01-08T19:19:13Z

syzbot reported a hang involving SCTP, on which it kept flooding dmesg with the message: [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 That happened because whenever SCTP hits an ICMP Frag Needed, it tries to adjust to the new MTU and triggers an immediate retransmission. But it didn't consider the fact that MTUs smaller than the SCTP minimum MTU allowed (512) would not cause the PMTU to change, and issued the retransmission anyway (thus leading to another ICMP Frag Needed, and so on). As IPv4 (ip_rt_min_pmtu=556) and IPv6 (IPV6_MIN_MTU=1280) minimum MTU are higher than that, sctp_transport_update_pmtu() is changed to re-fetch the PMTU that got set after our request, and with that, detect if there was an actual change or not. The fix, thus, skips the immediate retransmission if the received ICMP resulted in no change, in the hope that SCTP will select another path. Note: The value being used for the minimum MTU (512, SCTP_DEFAULT_MINSEGMENT) is not right and instead it should be (576, SCTP_MIN_PMTU), but such change belongs to another patch. Changes from v1: - do not disable PMTU discovery, in the light of commit 06ad391919b2 ("[SCTP] Don't disable PMTU discovery when mtu is small") and as suggested by Xin Long. - changed the way to break the rtx loop by detecting if the icmp resulted in a change or not Changes from v2: none See-also: https://lkml.org/lkml/2017/12/22/811 Reported-by: syzbot Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: do not retransmit upon FragNeeded if PMTU discovery is disabled

2018-01-08T19:19:13Z

Currently, if PMTU discovery is disabled on a given transport, but the configured value is higher than the actual PMTU, it is likely that we will get some icmp Frag Needed. The issue is, if PMTU discovery is disabled, we won't update the information and will issue a retransmission immediately, which may very well trigger another ICMP, and another retransmission, leading to a loop. The fix is to simply not trigger immediate retransmissions if PMTU discovery is disabled on the given transport. Changes from v2: - updated stale comment, noticed by Xin Long Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller