kernel.git/net/sctp/output.c, branch linux-5.11.y

sctp: move sk_route_caps check and set into sctp_outq_flush_transports

2021-03-30T12:30:24Z

[ Upstream commit 8ff0b1f08ea73e5c08f5addd23481e76a60e741c ] The sk's sk_route_caps is set in sctp_packet_config, and later it only needs to change when traversing the transport_list in a loop, as the dst might be changed in the tx path. So move sk_route_caps check and set into sctp_outq_flush_transports from sctp_packet_transmit. This also fixes a dst leak reported by Chen Yi: https://bugzilla.kernel.org/show_bug.cgi?id=212227 As calling sk_setup_caps() in sctp_packet_transmit may also set the sk_route_caps for the ctrl sock in a netns. When the netns is being deleted, the ctrl sock's releasing is later than dst dev's deleting, which will cause this dev's deleting to hang and dmesg error occurs: unregister_netdevice: waiting for xxx to become free. Usage count = 1 Reported-by: Chen Yi Fixes: bcd623d8e9fa ("sctp: call sk_setup_caps in sctp_packet_transmit instead") Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

sctp: support for sending packet over udp4 sock

2020-10-30T22:24:30Z

This patch does what the rfc6951#section-5.3 says for ipv4: "Within the UDP header, the source port MUST be the local UDP encapsulation port number of the SCTP stack, and the destination port MUST be the remote UDP encapsulation port number maintained for the association and the destination address to which the packet is sent (see Section 5.1). Because the SCTP packet is the UDP payload, the length of the UDP packet MUST be the length of the SCTP packet plus the size of the UDP header. The SCTP checksum MUST be computed for IPv4 and IPv6, and the UDP checksum SHOULD be computed for IPv4 and IPv6." Some places need to be adjusted in sctp_packet_transmit(): 1. For non-gso packets, when transport's encap_port is set, sctp checksum has to be done in sctp_packet_pack(), as the outer udp will use ip_summed = CHECKSUM_PARTIAL to do the offload setting for checksum. 2. Delay calling dst_clone() and skb_dst_set() for non-udp packets until sctp_v4_xmit(), as for udp packets, skb_dst_set() is not needed before calling udp_tunnel_xmit_skb(). then in sctp_v4_xmit(): 1. Go to udp_tunnel_xmit_skb() only when transport->encap_port and net->sctp.udp_port both are set, as these are one for dst port and another for src port. 2. For gso packet, SKB_GSO_UDP_TUNNEL_CSUM is set for gso_type, and with this udp checksum can be done in __skb_udp_tunnel_segment() for each segments after the sctp gso. 3. inner_mac_header and inner_transport_header are set, as these will be needed in __skb_udp_tunnel_segment() to find the right headers. 4. df and ttl are calculated, as these are the required params by udp_tunnel_xmit_skb(). 5. nocheck param has to be false, as "the UDP checksum SHOULD be computed for IPv4 and IPv6", says in rfc6951#section-5.3. v1->v2: - Use sp->udp_port instead in sctp_v4_xmit(), which is more safe. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski

sctp: call sk_setup_caps in sctp_packet_transmit instead

2020-10-30T22:24:25Z

sk_setup_caps() was originally called in Commit 90017accff61 ("sctp: Add GSO support"), as: "We have to refresh this in case we are xmiting to more than one transport at a time" This actually happens in the loop of sctp_outq_flush_transports(), and it shouldn't be tied to gso, so move it out of gso part and before sctp_packet_pack(). Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski

sctp: get netns from asoc and ep base

2019-12-10T04:14:01Z

Commit 312434617cb1 ("sctp: cache netns in sctp_ep_common") set netns in asoc and ep base since they're created, and it will never change. It's a better way to get netns from asoc and ep base, comparing to calling sock_net(). This patch is to replace them. v1->v2: - no change. Suggested-by: Marcelo Ricardo Leitner Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: count data bundling sack chunk for outctrlchunks

2019-07-03T18:41:24Z

Now all ctrl chunks are counted for asoc stats.octrlchunks and net SCTP_MIB_OUTCTRLCHUNKS either after queuing up or bundling, other than the chunk maked and bundled in sctp_packet_bundle_sack, which caused 'outctrlchunks' not consistent with 'inctrlchunks' in peer. This issue exists since very beginning, here to fix it by increasing both net SCTP_MIB_OUTCTRLCHUNKS and asoc stats.octrlchunks when sack chunk is maked and bundled in sctp_packet_bundle_sack. Reported-by: Ja Ram Jeon Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104

2019-05-24T15:39:00Z

Based on 1 normalized pattern(s): this sctp implementation is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version this sctp implementation is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with gnu cc see the file copying if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 42 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Kate Stewart Reviewed-by: Richard Fontana Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091649.683323110@linutronix.de Signed-off-by: Greg Kroah-Hartman

sctp: increase sk_wmem_alloc when head->truesize is increased

2018-11-27T23:42:31Z

I changed to count sk_wmem_alloc by skb truesize instead of 1 to fix the sk_wmem_alloc leak caused by later truesize's change in xfrm in Commit 02968ccf0125 ("sctp: count sk_wmem_alloc by skb truesize in sctp_packet_transmit"). But I should have also increased sk_wmem_alloc when head->truesize is increased in sctp_packet_gso_append() as xfrm does. Otherwise, sctp gso packet will cause sk_wmem_alloc underflow. Fixes: 02968ccf0125 ("sctp: count sk_wmem_alloc by skb truesize in sctp_packet_transmit") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

Revert "sctp: remove sctp_transport_pmtu_check"

2018-11-19T20:42:47Z

This reverts commit 22d7be267eaa8114dcc28d66c1c347f667d7878a. The dst's mtu in transport can be updated by a non sctp place like in xfrm where the MTU information didn't get synced between asoc, transport and dst, so it is still needed to do the pmtu check in sctp_packet_config. Acked-by: Neil Horman Signed-off-by: David S. Miller

sctp: count sk_wmem_alloc by skb truesize in sctp_packet_transmit

2018-11-19T20:39:05Z

Now sctp increases sk_wmem_alloc by 1 when doing set_owner_w for the skb allocked in sctp_packet_transmit and decreases by 1 when freeing this skb. But when this skb goes through networking stack, some subcomponents might change skb->truesize and add the same amount on sk_wmem_alloc. However sctp doesn't know the amount to decrease by, it would cause a leak on sk->sk_wmem_alloc and the sock can never be freed. Xiumei found this issue when it hit esp_output_head() by using sctp over ipsec, where skb->truesize is added and so is sk->sk_wmem_alloc. Since sctp has used sk_wmem_queued to count for writable space since Commit cd305c74b0f8 ("sctp: use sk_wmem_queued to check for writable space"), it's ok to fix it by counting sk_wmem_alloc by skb truesize in sctp_packet_transmit. Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Reported-by: Xiumei Mu Signed-off-by: Xin Long 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