Merge branch 'per-route-dctcp-receive-side'
Daniel Borkmann says:
====================
tcp: receive-side per route dctcp handling
Original cover letter:
Currently, the following case doesn't use DCTCP, even if it should:
- responder has f.e. cubic as system wide default
- 'ip route congctl dctcp $src' was set
Then, DCTCP is NOT used if a DCTCP sender attempts to connect from a
host in the $src range: ECT(0) is set, but listen_sk is not dctcp, so
we fail the INET_ECN_is_not_ect sanity check.
We also have to examine the dst used for the SYN/ACK reply to make
this case work.
In order to minimize additional cost, store the 'ecn is must have'
information is the dst_features field.
The set targets -next instead of -net since this doesn't seem to be a
serious bug and to give the change more soak time until it hits linus
tree.
v1 -> v2:
- Addressed Dave's feedback, not exposing any bits to user space
- Added patch 3 to reject incorrect configurations
- Rest as is, rebased and retested
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
