kernel/linux.git/net/sctp/outqueue.c, branch v6.12.80

sctp: delete the nested flexible array variable

2023-04-21T07:19:29+00:00

This patch deletes the flexible-array variable[] from the structure sctp_sackhdr and sctp_errhdr to avoid some sparse warnings: # make C=2 CF="-Wflexible-array-nested" M=./net/sctp/ net/sctp/sm_statefuns.c: note: in included file (through include/net/sctp/structs.h, include/net/sctp/sctp.h): ./include/linux/sctp.h:451:28: warning: nested flexible array ./include/linux/sctp.h:393:29: warning: nested flexible array Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: clear out_curr if all frag chunks of current msg are pruned

2022-11-08T03:59:01+00:00

A crash was reported by Zhen Chen: list_del corruption, ffffa035ddf01c18->next is NULL WARNING: CPU: 1 PID: 250682 at lib/list_debug.c:49 __list_del_entry_valid+0x59/0xe0 RIP: 0010:__list_del_entry_valid+0x59/0xe0 Call Trace: sctp_sched_dequeue_common+0x17/0x70 [sctp] sctp_sched_fcfs_dequeue+0x37/0x50 [sctp] sctp_outq_flush_data+0x85/0x360 [sctp] sctp_outq_uncork+0x77/0xa0 [sctp] sctp_cmd_interpreter.constprop.0+0x164/0x1450 [sctp] sctp_side_effects+0x37/0xe0 [sctp] sctp_do_sm+0xd0/0x230 [sctp] sctp_primitive_SEND+0x2f/0x40 [sctp] sctp_sendmsg_to_asoc+0x3fa/0x5c0 [sctp] sctp_sendmsg+0x3d5/0x440 [sctp] sock_sendmsg+0x5b/0x70 and in sctp_sched_fcfs_dequeue() it dequeued a chunk from stream out_curr outq while this outq was empty. Normally stream->out_curr must be set to NULL once all frag chunks of current msg are dequeued, as we can see in sctp_sched_dequeue_done(). However, in sctp_prsctp_prune_unsent() as it is not a proper dequeue, sctp_sched_dequeue_done() is not called to do this. This patch is to fix it by simply setting out_curr to NULL when the last frag chunk of current msg is dequeued from out_curr stream in sctp_prsctp_prune_unsent(). Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Reported-by: Zhen Chen Tested-by: Caowangbao Signed-off-by: Xin Long Signed-off-by: Jakub Kicinski

sctp: remove the unnecessary sinfo_stream check in sctp_prsctp_prune_unsent

2022-11-08T03:59:01+00:00

Since commit 5bbbbe32a431 ("sctp: introduce stream scheduler foundations"), sctp_stream_outq_migrate() has been called in sctp_stream_init/update to removes those chunks to streams higher than the new max. There is no longer need to do such check in sctp_prsctp_prune_unsent(). Signed-off-by: Xin Long Signed-off-by: Jakub Kicinski

sctp: count singleton chunks in assoc user stats

2022-04-05T07:51:12+00:00

Singleton chunks (INIT, HEARTBEAT PMTU probes, and SHUTDOWN- COMPLETE) are not counted in SCTP_GET_ASOC_STATS "sas_octrlchunks" counter available to the assoc owner. These are all control chunks so they should be counted as such. Add counting of singleton chunks so they are properly accounted for. Fixes: 196d67593439 ("sctp: Add support to per-association statistics via a new SCTP_GET_ASSOC_STATS call") Signed-off-by: Jamie Bainbridge Acked-by: Marcelo Ricardo Leitner Link: https://lore.kernel.org/r/c9ba8785789880cf07923b8a5051e174442ea9ee.1649029663.git.jamie.bainbridge@gmail.com Signed-off-by: Paolo Abeni

sctp: make the raise timer more simple and accurate

2021-11-26T05:00:45+00:00

Currently, the probe timer is reused as the raise timer when PLPMTUD is in the Search Complete state. raise_count was introduced to count how many times the probe timer has timed out. When raise_count reaches to 30, the raise timer handler will be triggered. During the whole processing above, the timer keeps timing out every probe_ interval. It is a waste for the Search Complete state, as the raise timer only needs to time out after 30 * probe_interval. Since the raise timer and probe timer are never used at the same time, it is no need to keep probe timer 'alive' in the Search Complete state. This patch to introduce sctp_transport_reset_raise_timer() to start the timer as the raise timer when entering the Search Complete state. When entering the other states, sctp_transport_reset_probe_timer() will still be called to reset the timer to the probe timer. raise_count can be removed from sctp_transport as no need to count probe timer timeout for raise timer timeout. last_rtx_chunks can be removed as sctp_transport_reset_probe_timer() can be called in the place where asoc rtx_data_chunks is changed. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Link: https://lore.kernel.org/r/edb0e48988ea85997488478b705b11ddc1ba724a.1637781974.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski

sctp: do the basic send and recv for PLPMTUD probe

2021-06-22T18:28:52+00:00

This patch does exactly what rfc8899#section-6.2.1.2 says: The SCTP sender needs to be able to determine the total size of a probe packet. The HEARTBEAT chunk could carry a Heartbeat Information parameter that includes, besides the information suggested in [RFC4960], the probe size to help an implementation associate a HEARTBEAT ACK with the size of probe that was sent. The sender could also use other methods, such as sending a nonce and verifying the information returned also contains the corresponding nonce. The length of the PAD chunk is computed by reducing the probing size by the size of the SCTP common header and the HEARTBEAT chunk. Note that HB ACK chunk will carry back whatever HB chunk carried, including the probe_size we put it in; We also check hbinfo->probe_size in the HB ACK against link->pl.probe_size to validate this HB ACK chunk. v1->v2: - Remove the unused 'sp' and add static for sctp_packet_bundle_pad(). Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: move sk_route_caps check and set into sctp_outq_flush_transports

2021-03-19T18:34:49+00:00

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

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

sctp: add enabled check for path tracepoint loop.

2019-12-31T04:33:05+00:00

sctp_outq_sack is the main function handles SACK, it is called very frequently. As the commit "move trace_sctp_probe_path into sctp_outq_sack" added below code to this function, sctp tracepoint is disabled most of time, but the loop of transport list will be always called even though the tracepoint is disabled, this is unnecessary. + /* SCTP path tracepoint for congestion control debugging. */ + list_for_each_entry(transport, transport_list, transports) { + trace_sctp_probe_path(transport, asoc); + } This patch is to add tracepoint enabled check at outside of the loop of transport list, and avoid traversing the loop when trace is disabled, it is a small optimization. Signed-off-by: Kevin Kou Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: move trace_sctp_probe_path into sctp_outq_sack

2019-12-26T21:06:45+00:00

The original patch bringed in the "SCTP ACK tracking trace event" feature was committed at Dec.20, 2017, it replaced jprobe usage with trace events, and bringed in two trace events, one is TRACE_EVENT(sctp_probe), another one is TRACE_EVENT(sctp_probe_path). The original patch intended to trigger the trace_sctp_probe_path in TRACE_EVENT(sctp_probe) as below code, +TRACE_EVENT(sctp_probe, + + TP_PROTO(const struct sctp_endpoint *ep, + const struct sctp_association *asoc, + struct sctp_chunk *chunk), + + TP_ARGS(ep, asoc, chunk), + + TP_STRUCT__entry( + __field(__u64, asoc) + __field(__u32, mark) + __field(__u16, bind_port) + __field(__u16, peer_port) + __field(__u32, pathmtu) + __field(__u32, rwnd) + __field(__u16, unack_data) + ), + + TP_fast_assign( + struct sk_buff *skb = chunk->skb; + + __entry->asoc = (unsigned long)asoc; + __entry->mark = skb->mark; + __entry->bind_port = ep->base.bind_addr.port; + __entry->peer_port = asoc->peer.port; + __entry->pathmtu = asoc->pathmtu; + __entry->rwnd = asoc->peer.rwnd; + __entry->unack_data = asoc->unack_data; + + if (trace_sctp_probe_path_enabled()) { + struct sctp_transport *sp; + + list_for_each_entry(sp, &asoc->peer.transport_addr_list, + transports) { + trace_sctp_probe_path(sp, asoc); + } + } + ), But I found it did not work when I did testing, and trace_sctp_probe_path had no output, I finally found that there is trace buffer lock operation(trace_event_buffer_reserve) in include/trace/trace_events.h: static notrace void \ trace_event_raw_event_##call(void *__data, proto) \ { \ struct trace_event_file *trace_file = __data; \ struct trace_event_data_offsets_##call __maybe_unused __data_offsets;\ struct trace_event_buffer fbuffer; \ struct trace_event_raw_##call *entry; \ int __data_size; \ \ if (trace_trigger_soft_disabled(trace_file)) \ return; \ \ __data_size = trace_event_get_offsets_##call(&__data_offsets, args); \ \ entry = trace_event_buffer_reserve(&fbuffer, trace_file, \ sizeof(*entry) + __data_size); \ \ if (!entry) \ return; \ \ tstruct \ \ { assign; } \ \ trace_event_buffer_commit(&fbuffer); \ } The reason caused no output of trace_sctp_probe_path is that trace_sctp_probe_path written in TP_fast_assign part of TRACE_EVENT(sctp_probe), and it will be placed( { assign; } ) after the trace_event_buffer_reserve() when compiler expands Macro, entry = trace_event_buffer_reserve(&fbuffer, trace_file, \ sizeof(*entry) + __data_size); \ \ if (!entry) \ return; \ \ tstruct \ \ { assign; } \ so trace_sctp_probe_path finally can not acquire trace_event_buffer and return no output, that is to say the nest of tracepoint entry function is not allowed. The function call flow is: trace_sctp_probe() -> trace_event_raw_event_sctp_probe() -> lock buffer -> trace_sctp_probe_path() -> trace_event_raw_event_sctp_probe_path() --nested -> buffer has been locked and return no output. This patch is to remove trace_sctp_probe_path from the TP_fast_assign part of TRACE_EVENT(sctp_probe) to avoid the nest of entry function, and trigger sctp_probe_path_trace in sctp_outq_sack. After this patch, you can enable both events individually, # cd /sys/kernel/debug/tracing # echo 1 > events/sctp/sctp_probe/enable # echo 1 > events/sctp/sctp_probe_path/enable Or, you can enable all the events under sctp. # echo 1 > events/sctp/enable Signed-off-by: Kevin Kou Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller