In this series, we mainly add some skb drop reasons to the input path of
ip routing, and we make the following functions return drop reasons:

  fib_validate_source()
  ip_route_input_mc()
  ip_mc_validate_source()
  ip_route_input_slow()
  ip_route_input_rcu()
  ip_route_input_noref()
  ip_route_input()
  ip_mkroute_input()
  __mkroute_input()
  ip_route_use_hint()

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 v4:
- in the 6th patch: remove the unneeded "else" in ip_expire()
- in the 8th patch: delete the unneeded comment in __mkroute_input()
- in the 9th patch: replace "return 0" with "return SKB_NOT_DROPPED_YET"
  in ip_route_use_hint()

Changes since v3:
- don't refactor fib_validate_source/__fib_validate_source, and introduce
  a wrapper for fib_validate_source() instead in the 1st patch.
- some small adjustment in the 4-7 patches

Changes since v2:
- refactor fib_validate_source and __fib_validate_source to make
  fib_validate_source return drop reasons
- add the 9th and 10th patches to make this series cover the input route
  code path

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 (9):
  net: ip: make fib_validate_source() support drop reasons
  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
  net: ip: make ip_mkroute_input/__mkroute_input return drop reasons
  net: ip: make ip_route_use_hint() return drop reasons

 include/net/dropreason-core.h   |  26 ++++
 include/net/ip_fib.h            |  12 ++
 include/net/route.h             |  34 ++---
 net/bridge/br_netfilter_hooks.c |  11 +-
 net/core/lwt_bpf.c              |   6 +-
 net/ipv4/fib_frontend.c         |  17 ++-
 net/ipv4/icmp.c                 |   2 +-
 net/ipv4/ip_fragment.c          |  11 +-
 net/ipv4/ip_input.c             |  20 ++-
 net/ipv4/ip_options.c           |   2 +-
 net/ipv4/route.c                | 211 ++++++++++++++++++--------------
 net/ipv6/seg6_local.c           |  14 +--
 12 files changed, 225 insertions(+), 141 deletions(-)

-- 
2.39.5