5.15-stable review patch. If anyone has any objections, please let me know.
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From: "Matthieu Baerts (NGI0)" matttbe@kernel.org
commit 4dde0d72ccec500c60c798e036b852e013d6e124 upstream.
Without such counters, it is difficult to easily debug issues with MPJ not having the backup flags on production servers.
This is not strictly a fix, but it eases to validate the following patches without requiring to take packet traces, to query ongoing connections with Netlink with admin permissions, or to guess by looking at the behaviour of the packet scheduler. Also, the modification is self contained, isolated, well controlled, and the increments are done just after others, there from the beginning. It looks then safe, and helpful to backport this.
Fixes: 4596a2c1b7f5 ("mptcp: allow creating non-backup subflows") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Signed-off-by: Paolo Abeni pabeni@redhat.com [ Conflicts in subflow.c because the context has changed in commit b3ea6b272d79 ("mptcp: consolidate initial ack seq generation") which is not in this version. This commit is unrelated to this modification. ] Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/mib.c | 2 ++ net/mptcp/mib.h | 2 ++ net/mptcp/subflow.c | 6 ++++++ 3 files changed, 10 insertions(+)
--- a/net/mptcp/mib.c +++ b/net/mptcp/mib.c @@ -19,7 +19,9 @@ static const struct snmp_mib mptcp_snmp_ SNMP_MIB_ITEM("MPTCPRetrans", MPTCP_MIB_RETRANSSEGS), SNMP_MIB_ITEM("MPJoinNoTokenFound", MPTCP_MIB_JOINNOTOKEN), 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("MPJoinAckRx", MPTCP_MIB_JOINACKRX), SNMP_MIB_ITEM("MPJoinAckHMacFailure", MPTCP_MIB_JOINACKMAC), --- a/net/mptcp/mib.h +++ b/net/mptcp/mib.h @@ -12,7 +12,9 @@ enum linux_mptcp_mib_field { MPTCP_MIB_RETRANSSEGS, /* Segments retransmitted at the MPTCP-level */ MPTCP_MIB_JOINNOTOKEN, /* Received MP_JOIN but the token was not found */ MPTCP_MIB_JOINSYNRX, /* Received a SYN + MP_JOIN */ + MPTCP_MIB_JOINSYNBACKUPRX, /* Received a SYN + MP_JOIN + backup flag */ MPTCP_MIB_JOINSYNACKRX, /* Received a SYN/ACK + MP_JOIN */ + MPTCP_MIB_JOINSYNACKBACKUPRX, /* Received a SYN/ACK + MP_JOIN + backup flag */ MPTCP_MIB_JOINSYNACKMAC, /* HMAC was wrong on SYN/ACK + MP_JOIN */ MPTCP_MIB_JOINACKRX, /* Received an ACK + MP_JOIN */ MPTCP_MIB_JOINACKMAC, /* HMAC was wrong on ACK + MP_JOIN */ --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -163,6 +163,9 @@ static int subflow_check_req(struct requ return 0; } else if (opt_mp_join) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNRX); + + if (mp_opt.backup) + SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNBACKUPRX); }
if (opt_mp_capable && listener->request_mptcp) { @@ -462,6 +465,9 @@ static void subflow_finish_connect(struc subflow->mp_join = 1; MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX);
+ if (subflow->backup) + MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKBACKUPRX); + if (subflow_use_different_dport(mptcp_sk(parent), sk)) { pr_debug("synack inet_dport=%d %d", ntohs(inet_sk(sk)->inet_dport),