[PATCH net-next v2 0/7] net: ip: add drop reasons to input route

[Menglong Dong]

In this series, we mainly add some skb drop reasons to the input path of
ip routing.

The errno from fib_validate_source() is -EINVAL or -EXDEV, and -EXDEV is
used in ip_rcv_finish_core() to increase the LINUX_MIB_IPRPFILTER. For
this case, we can check it by
"drop_reason == SKB_DROP_REASON_IP_RPFILTER" instead. Therefore, we can
make fib_validate_source() return -reason.

Meanwhile, we make the following functions return drop reasons too:

  ip_route_input_mc()
  ip_mc_validate_source()
  ip_route_input_slow()
  ip_route_input_rcu()
  ip_route_input_noref()
  ip_route_input()

And following new skb drop reasons are added:

  SKB_DROP_REASON_IP_LOCAL_SOURCE
  SKB_DROP_REASON_IP_INVALID_SOURCE
  SKB_DROP_REASON_IP_LOCALNET
  SKB_DROP_REASON_IP_INVALID_DEST

Changes since v1:
- make ip_route_input_noref/ip_route_input_rcu/ip_route_input_slow return
  drop reasons, instead of passing a local variable to their function
  arguments.

Menglong Dong (7):
  net: ip: make fib_validate_source() return drop reason
  net: ip: make ip_route_input_mc() return drop reason
  net: ip: make ip_mc_validate_source() return drop reason
  net: ip: make ip_route_input_slow() return drop reasons
  net: ip: make ip_route_input_rcu() return drop reasons
  net: ip: make ip_route_input_noref() return drop reasons
  net: ip: make ip_route_input() return drop reasons

 include/net/dropreason-core.h   |  19 +++++
 include/net/route.h             |  27 ++++---
 net/bridge/br_netfilter_hooks.c |  11 +--
 net/core/lwt_bpf.c              |   1 +
 net/ipv4/fib_frontend.c         |  19 +++--
 net/ipv4/icmp.c                 |   1 +
 net/ipv4/ip_fragment.c          |  12 +--
 net/ipv4/ip_input.c             |  11 ++-
 net/ipv4/route.c                | 131 +++++++++++++++++++-------------
 9 files changed, 145 insertions(+), 87 deletions(-)

-- 
2.39.5