From: Matthieu Baerts (NGI0) Date: Sat, 27 Jul 2024 10:01:24 +0000 (+0200) Subject: mptcp: distinguish rcv vs sent backup flag in requests X-Git-Tag: v6.10.4~11 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=73e2baa301ee3f62ff971e68877adeb37f98cc67;p=thirdparty%2Fkernel%2Fstable.git mptcp: distinguish rcv vs sent backup flag in requests commit efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 upstream. When sending an MP_JOIN + SYN + ACK, it is possible to mark the subflow as 'backup' by setting the flag with the same name. Before this patch, the backup was set if the other peer set it in its MP_JOIN + SYN request. It is not correct: the backup flag should be set in the MPJ+SYN+ACK only if the host asks for it, and not mirroring what was done by the other peer. It is then required to have a dedicated bit for each direction, similar to what is done in the subflow context. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts (NGI0) Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 8e8dcfbc29938..8a68382a4fe91 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -909,7 +909,7 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size, return true; } else if (subflow_req->mp_join) { opts->suboptions = OPTION_MPTCP_MPJ_SYNACK; - opts->backup = subflow_req->backup; + opts->backup = subflow_req->request_bkup; opts->join_id = subflow_req->local_id; opts->thmac = subflow_req->thmac; opts->nonce = subflow_req->local_nonce; diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 7aa47e2dd52b1..bd7fe1db21a00 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -443,6 +443,7 @@ struct mptcp_subflow_request_sock { u16 mp_capable : 1, mp_join : 1, backup : 1, + request_bkup : 1, csum_reqd : 1, allow_join_id0 : 1; u8 local_id; diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 612c38570a642..616929fa29924 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -2005,6 +2005,7 @@ static void subflow_ulp_clone(const struct request_sock *req, new_ctx->fully_established = 1; new_ctx->remote_key_valid = 1; new_ctx->backup = subflow_req->backup; + new_ctx->request_bkup = subflow_req->request_bkup; WRITE_ONCE(new_ctx->remote_id, subflow_req->remote_id); new_ctx->token = subflow_req->token; new_ctx->thmac = subflow_req->thmac;