Files
Shardul Bankar 3420c0fd7e mptcp: add per-event MIB counters for MPTCP_RST_EMPTCP resets
MPTCP_RST_EMPTCP (reset reason 1) is used as a catch-all for several
distinct error conditions across subflow setup, authentication, and
data-path validation.  The existing MPRstTx/MPRstRx counters only
track aggregate reset volume, making it difficult to diagnose which
code path is triggering subflow resets in production.

Add per-event MIB counters covering each MPTCP_RST_EMPTCP use site
that is not already covered by an existing counter, named after the
underlying event or condition rather than the reset action:

  MD5SigReset           MD5SIG enabled on listener (incompatible)
  MPJoinSynAckNoMPJoin  SYN/ACK missing MP_JOIN option
  MPJoinAckNoMPJoin     server-side ACK missing MP_JOIN option
                          (fallback path, MPJoin required)
  MPJoinAckNoCtx        server-side ACK with no subflow context
  MPJoinNoIdFound       MP_JOIN with a valid token but no PM local ID
  DssReset              data mapping invalid (also fires on
                          MAPPING_NODSS / EMIDDLEBOX path)
  MPJoinNotEstablished  JOIN attempted on a not-fully-established msk

MPJoinNoIdFound covers the second half of the no-msk MP_JOIN reset:
the existing MPJoinNoTokenFound (MPTCP_MIB_JOINNOTOKEN) only counts the
missing-token case in subflow_token_join_request(), while a JOIN that
carries a valid token but for which the path manager returns no local
id reaches the same MPTCP_RST_EMPTCP in subflow_check_req() uncounted.

The aggregate MPRstTx/MPRstRx counters are unchanged.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/511
Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260812-net-next-mptcp-misc-feat-7-3-v1-5-1905a818f6cb@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-17 17:25:49 -07:00

141 lines
6.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/seq_file.h>
#include <net/ip.h>
#include <net/mptcp.h>
#include <net/snmp.h>
#include <net/net_namespace.h>
#include "mib.h"
static const struct snmp_mib mptcp_snmp_list[] = {
SNMP_MIB_ITEM("MPCapableSYNRX", MPTCP_MIB_MPCAPABLEPASSIVE),
SNMP_MIB_ITEM("MPCapableSYNTX", MPTCP_MIB_MPCAPABLEACTIVE),
SNMP_MIB_ITEM("MPCapableSYNACKRX", MPTCP_MIB_MPCAPABLEACTIVEACK),
SNMP_MIB_ITEM("MPCapableACKRX", MPTCP_MIB_MPCAPABLEPASSIVEACK),
SNMP_MIB_ITEM("MPCapableFallbackACK", MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK),
SNMP_MIB_ITEM("MPCapableFallbackSYNACK", MPTCP_MIB_MPCAPABLEACTIVEFALLBACK),
SNMP_MIB_ITEM("MPCapableSYNTXDrop", MPTCP_MIB_MPCAPABLEACTIVEDROP),
SNMP_MIB_ITEM("MPCapableSYNTXDisabled", MPTCP_MIB_MPCAPABLEACTIVEDISABLED),
SNMP_MIB_ITEM("MPCapableEndpAttempt", MPTCP_MIB_MPCAPABLEENDPATTEMPT),
SNMP_MIB_ITEM("MPFallbackTokenInit", MPTCP_MIB_TOKENFALLBACKINIT),
SNMP_MIB_ITEM("MPTCPRetrans", MPTCP_MIB_RETRANSSEGS),
SNMP_MIB_ITEM("MPJoinNoTokenFound", MPTCP_MIB_JOINNOTOKEN),
SNMP_MIB_ITEM("MPJoinNoIdFound", MPTCP_MIB_MPJOINNOIDFOUND),
SNMP_MIB_ITEM("MPJoinSynRx", MPTCP_MIB_JOINSYNRX),
SNMP_MIB_ITEM("MPJoinSynBackupRx", MPTCP_MIB_JOINSYNBACKUPRX),
SNMP_MIB_ITEM("MPJoinSynAckRx", MPTCP_MIB_JOINSYNACKRX),
SNMP_MIB_ITEM("MPJoinSynAckBackupRx", MPTCP_MIB_JOINSYNACKBACKUPRX),
SNMP_MIB_ITEM("MPJoinSynAckHMacFailure", MPTCP_MIB_JOINSYNACKMAC),
SNMP_MIB_ITEM("MPJoinSynAckNoMPJoin", MPTCP_MIB_MPJOINSYNACKNOMPJOIN),
SNMP_MIB_ITEM("MPJoinAckRx", MPTCP_MIB_JOINACKRX),
SNMP_MIB_ITEM("MPJoinAckHMacFailure", MPTCP_MIB_JOINACKMAC),
SNMP_MIB_ITEM("MPJoinAckNoMPJoin", MPTCP_MIB_MPJOINACKNOMPJOIN),
SNMP_MIB_ITEM("MPJoinAckNoCtx", MPTCP_MIB_MPJOINACKNOCTX),
SNMP_MIB_ITEM("MPJoinRejected", MPTCP_MIB_JOINREJECTED),
SNMP_MIB_ITEM("MPJoinNotEstablished", MPTCP_MIB_MPJOINNOTESTABLISHED),
SNMP_MIB_ITEM("MPJoinSynTx", MPTCP_MIB_JOINSYNTX),
SNMP_MIB_ITEM("MPJoinSynTxCreatSkErr", MPTCP_MIB_JOINSYNTXCREATSKERR),
SNMP_MIB_ITEM("MPJoinSynTxBindErr", MPTCP_MIB_JOINSYNTXBINDERR),
SNMP_MIB_ITEM("MPJoinSynTxConnectErr", MPTCP_MIB_JOINSYNTXCONNECTERR),
SNMP_MIB_ITEM("DSSNotMatching", MPTCP_MIB_DSSNOMATCH),
SNMP_MIB_ITEM("DSSCorruptionFallback", MPTCP_MIB_DSSCORRUPTIONFALLBACK),
SNMP_MIB_ITEM("DSSCorruptionReset", MPTCP_MIB_DSSCORRUPTIONRESET),
SNMP_MIB_ITEM("InfiniteMapTx", MPTCP_MIB_INFINITEMAPTX),
SNMP_MIB_ITEM("InfiniteMapRx", MPTCP_MIB_INFINITEMAPRX),
SNMP_MIB_ITEM("DSSNoMatchTCP", MPTCP_MIB_DSSTCPMISMATCH),
SNMP_MIB_ITEM("DataCsumErr", MPTCP_MIB_DATACSUMERR),
SNMP_MIB_ITEM("OFOQueueTail", MPTCP_MIB_OFOQUEUETAIL),
SNMP_MIB_ITEM("OFOQueue", MPTCP_MIB_OFOQUEUE),
SNMP_MIB_ITEM("OFOMerge", MPTCP_MIB_OFOMERGE),
SNMP_MIB_ITEM("NoDSSInWindow", MPTCP_MIB_NODSSWINDOW),
SNMP_MIB_ITEM("DuplicateData", MPTCP_MIB_DUPDATA),
SNMP_MIB_ITEM("AddAddr", MPTCP_MIB_ADDADDR),
SNMP_MIB_ITEM("AddAddrTx", MPTCP_MIB_ADDADDRTX),
SNMP_MIB_ITEM("AddAddrTxDrop", MPTCP_MIB_ADDADDRTXDROP),
SNMP_MIB_ITEM("EchoAdd", MPTCP_MIB_ECHOADD),
SNMP_MIB_ITEM("EchoAddTx", MPTCP_MIB_ECHOADDTX),
SNMP_MIB_ITEM("EchoAddTxDrop", MPTCP_MIB_ECHOADDTXDROP),
SNMP_MIB_ITEM("PortAdd", MPTCP_MIB_PORTADD),
SNMP_MIB_ITEM("AddAddrDrop", MPTCP_MIB_ADDADDRDROP),
SNMP_MIB_ITEM("MPJoinPortSynRx", MPTCP_MIB_JOINPORTSYNRX),
SNMP_MIB_ITEM("MPJoinPortSynAckRx", MPTCP_MIB_JOINPORTSYNACKRX),
SNMP_MIB_ITEM("MPJoinPortAckRx", MPTCP_MIB_JOINPORTACKRX),
SNMP_MIB_ITEM("MismatchPortSynRx", MPTCP_MIB_MISMATCHPORTSYNRX),
SNMP_MIB_ITEM("MismatchPortAckRx", MPTCP_MIB_MISMATCHPORTACKRX),
SNMP_MIB_ITEM("RmAddr", MPTCP_MIB_RMADDR),
SNMP_MIB_ITEM("RmAddrDrop", MPTCP_MIB_RMADDRDROP),
SNMP_MIB_ITEM("RmAddrTx", MPTCP_MIB_RMADDRTX),
SNMP_MIB_ITEM("RmAddrTxDrop", MPTCP_MIB_RMADDRTXDROP),
SNMP_MIB_ITEM("RmSubflow", MPTCP_MIB_RMSUBFLOW),
SNMP_MIB_ITEM("MPPrioTx", MPTCP_MIB_MPPRIOTX),
SNMP_MIB_ITEM("MPPrioRx", MPTCP_MIB_MPPRIORX),
SNMP_MIB_ITEM("MPFailTx", MPTCP_MIB_MPFAILTX),
SNMP_MIB_ITEM("MPFailRx", MPTCP_MIB_MPFAILRX),
SNMP_MIB_ITEM("MPFastcloseTx", MPTCP_MIB_MPFASTCLOSETX),
SNMP_MIB_ITEM("MPFastcloseRx", MPTCP_MIB_MPFASTCLOSERX),
SNMP_MIB_ITEM("MPRstTx", MPTCP_MIB_MPRSTTX),
SNMP_MIB_ITEM("MPRstRx", MPTCP_MIB_MPRSTRX),
SNMP_MIB_ITEM("SubflowStale", MPTCP_MIB_SUBFLOWSTALE),
SNMP_MIB_ITEM("SubflowRecover", MPTCP_MIB_SUBFLOWRECOVER),
SNMP_MIB_ITEM("SndWndShared", MPTCP_MIB_SNDWNDSHARED),
SNMP_MIB_ITEM("RcvWndShared", MPTCP_MIB_RCVWNDSHARED),
SNMP_MIB_ITEM("RcvWndConflictUpdate", MPTCP_MIB_RCVWNDCONFLICTUPDATE),
SNMP_MIB_ITEM("RcvWndConflict", MPTCP_MIB_RCVWNDCONFLICT),
SNMP_MIB_ITEM("MPCurrEstab", MPTCP_MIB_CURRESTAB),
SNMP_MIB_ITEM("Blackhole", MPTCP_MIB_BLACKHOLE),
SNMP_MIB_ITEM("MPCapableDataFallback", MPTCP_MIB_MPCAPABLEDATAFALLBACK),
SNMP_MIB_ITEM("MD5SigFallback", MPTCP_MIB_MD5SIGFALLBACK),
SNMP_MIB_ITEM("MD5SigReset", MPTCP_MIB_MD5SIGRESET),
SNMP_MIB_ITEM("DssFallback", MPTCP_MIB_DSSFALLBACK),
SNMP_MIB_ITEM("DssReset", MPTCP_MIB_DSSRESET),
SNMP_MIB_ITEM("SimultConnectFallback", MPTCP_MIB_SIMULTCONNFALLBACK),
SNMP_MIB_ITEM("FallbackFailed", MPTCP_MIB_FALLBACKFAILED),
SNMP_MIB_ITEM("WinProbe", MPTCP_MIB_WINPROBE),
SNMP_MIB_ITEM("BacklogDrop", MPTCP_MIB_BACKLOGDROP),
SNMP_MIB_ITEM("RcvPruned", MPTCP_MIB_RCVPRUNED),
SNMP_MIB_ITEM("OFOPruned", MPTCP_MIB_OFOPRUNED),
};
/* mptcp_mib_alloc - allocate percpu mib counters
*
* These are allocated when the first mptcp socket is created so
* we do not waste percpu memory if mptcp isn't in use.
*/
bool mptcp_mib_alloc(struct net *net)
{
struct mptcp_mib __percpu *mib = alloc_percpu(struct mptcp_mib);
if (!mib)
return false;
if (cmpxchg(&net->mib.mptcp_statistics, NULL, mib))
free_percpu(mib);
return true;
}
void mptcp_seq_show(struct seq_file *seq)
{
unsigned long sum[ARRAY_SIZE(mptcp_snmp_list)];
const int cnt = ARRAY_SIZE(mptcp_snmp_list);
struct net *net = seq->private;
int i;
seq_puts(seq, "MPTcpExt:");
for (i = 0; i < cnt; i++)
seq_printf(seq, " %s", mptcp_snmp_list[i].name);
seq_puts(seq, "\nMPTcpExt:");
memset(sum, 0, sizeof(sum));
if (net->mib.mptcp_statistics)
snmp_get_cpu_field_batch_cnt(sum, mptcp_snmp_list, cnt,
net->mib.mptcp_statistics);
for (i = 0; i < cnt; i++)
seq_printf(seq, " %lu", sum[i]);
seq_putc(seq, '\n');
}