diff options
| author | Davide Caratti <dcaratti@redhat.com> | 2020-10-06 18:26:17 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-10-09 08:25:48 -0700 |
| commit | 37198e93ced70733f0b993dff28b7c33857e254f (patch) | |
| tree | 5efe9e0415abf424ed26afd3563052862864ebe4 /net/mptcp/options.c | |
| parent | 0da1ccbbefb662915228bc17e1c7d4ad28b3ddab (diff) | |
net: mptcp: make DACK4/DACK8 usage consistent among all subflows
using packetdrill it's possible to observe the same MPTCP DSN being acked
by different subflows with DACK4 and DACK8. This is in contrast with what
specified in RFC8684 ยง3.3.2: if an MPTCP endpoint transmits a 64-bit wide
DSN, it MUST be acknowledged with a 64-bit wide DACK. Fix 'use_64bit_ack'
variable to make it a property of MPTCP sockets, not TCP subflows.
Fixes: a0c1d0eafd1e ("mptcp: Use 32-bit DATA_ACK when possible")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/options.c')
| -rw-r--r-- | net/mptcp/options.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 888bbbbb3e8a..9d7fa93fe0cf 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -516,7 +516,7 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb, return ret; } - if (subflow->use_64bit_ack) { + if (READ_ONCE(msk->use_64bit_ack)) { ack_size = TCPOLEN_MPTCP_DSS_ACK64; opts->ext_copy.data_ack = READ_ONCE(msk->ack_seq); opts->ext_copy.ack64 = 1; |