On Tue, Aug 13, 2024 at 11:06:07AM +0200, Matthieu Baerts (NGI0) wrote: > commit d67c5649c1541dc93f202eeffc6f49220a4ed71d upstream. > > Before this patch, receiving an ADD_ADDR echo on the just connected > MP_JOIN subflow -- initiator side, after the MP_JOIN 3WHS -- was > resulting in an MP_RESET. That's because only ACKs with a DSS or > ADD_ADDRs without the echo bit were allowed. > > Not allowing the ADD_ADDR echo after an MP_CAPABLE 3WHS makes sense, as > we are not supposed to send an ADD_ADDR before because it requires to be > in full established mode first. For the MP_JOIN 3WHS, that's different: > the ADD_ADDR can be sent on a previous subflow, and the ADD_ADDR echo > can be received on the recently created one. The other peer will already > be in fully established, so it is allowed to send that. > > We can then relax the conditions here to accept the ADD_ADDR echo for > MPJ subflows. > > Fixes: 67b12f792d5e ("mptcp: full fully established support after ADD_ADDR") > Cc: stable@xxxxxxxxxxxxxxx > Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx> > Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> > Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-1-c8a9b036493b@xxxxxxxxxx > Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> > [ Conflicts in options.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@xxxxxxxxxx> > --- > net/mptcp/options.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) Now queued up, thanks. greg k-h