mptcp: introduce MAPPING_BAD_CSUM

This allow moving a couple of conditional out of the fast path,
making the code more easy to follow and will simplify the next
patch.

Fixes: ae66fb2ba6 ("mptcp: Do TCP fallback on early DSS checksum failure")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paolo Abeni 2022-06-27 18:02:36 -07:00 committed by Jakub Kicinski
parent 0c1f78a49a
commit 31bf11de14

View File

@ -843,7 +843,8 @@ enum mapping_status {
MAPPING_INVALID,
MAPPING_EMPTY,
MAPPING_DATA_FIN,
MAPPING_DUMMY
MAPPING_DUMMY,
MAPPING_BAD_CSUM
};
static void dbg_bad_map(struct mptcp_subflow_context *subflow, u32 ssn)
@ -958,9 +959,7 @@ static enum mapping_status validate_data_csum(struct sock *ssk, struct sk_buff *
subflow->map_data_csum);
if (unlikely(csum)) {
MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DATACSUMERR);
if (subflow->mp_join || subflow->valid_csum_seen)
subflow->send_mp_fail = 1;
return subflow->mp_join ? MAPPING_INVALID : MAPPING_DUMMY;
return MAPPING_BAD_CSUM;
}
subflow->valid_csum_seen = 1;
@ -1182,10 +1181,8 @@ static bool subflow_check_data_avail(struct sock *ssk)
status = get_mapping_status(ssk, msk);
trace_subflow_check_data_avail(status, skb_peek(&ssk->sk_receive_queue));
if (unlikely(status == MAPPING_INVALID))
goto fallback;
if (unlikely(status == MAPPING_DUMMY))
if (unlikely(status == MAPPING_INVALID || status == MAPPING_DUMMY ||
status == MAPPING_BAD_CSUM))
goto fallback;
if (status != MAPPING_OK)
@ -1227,7 +1224,10 @@ no_data:
fallback:
if (!__mptcp_check_fallback(msk)) {
/* RFC 8684 section 3.7. */
if (subflow->send_mp_fail) {
if (status == MAPPING_BAD_CSUM &&
(subflow->mp_join || subflow->valid_csum_seen)) {
subflow->send_mp_fail = 1;
if (!READ_ONCE(msk->allow_infinite_fallback)) {
ssk->sk_err = EBADMSG;
tcp_set_state(ssk, TCP_CLOSE);