From: "Matthieu Baerts (NGI0)" <matttbe@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
[ Conflicts in subflow.c, because the context has changed in commit
4cf86ae84c71 ("mptcp: strict local address ID selection"), and in
commit 967d3c27127e ("mptcp: fix data races on remote_id"), which are
not in this version. These commits are unrelated to this
modification. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mptcp/options.c | 2 +-
net/mptcp/protocol.h | 1 +
net/mptcp/subflow.c | 1 +
3 files changed, 3 insertions(+), 1 deletion(-)
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -877,7 +877,7 @@ bool mptcp_synack_options(const struct r
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;
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -370,6 +370,7 @@ 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;
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1766,6 +1766,7 @@ static void subflow_ulp_clone(const stru
new_ctx->mp_join = 1;
new_ctx->fully_established = 1;
new_ctx->backup = subflow_req->backup;
+ new_ctx->request_bkup = subflow_req->request_bkup;
new_ctx->local_id = subflow_req->local_id;
new_ctx->remote_id = subflow_req->remote_id;
new_ctx->token = subflow_req->token;
Patches currently in stable-queue which might be from kroah.com@xxxxxxxxxxxxxxx are
queue-5.15/mptcp-fix-nl-pm-announced-address-accounting.patch
queue-5.15/mptcp-distinguish-rcv-vs-sent-backup-flag-in-requests.patch
queue-5.15/mptcp-pm-fix-backup-support-in-signal-endpoints.patch
queue-5.15/mptcp-mib-count-mpj-with-backup-flag.patch
queue-5.15/selftests-mptcp-join-validate-backup-in-mpj.patch
queue-5.15/mptcp-export-local_address.patch
queue-5.15/mptcp-pm-only-set-request_bkup-flag-when-sending-mp_prio.patch
queue-5.15/mptcp-fix-bad-rcvpruned-mib-accounting.patch
