[PATCH v5 0/2] Make neighbor eviction controllable by userspace

[James Prestwood <prestwoj@gmail.com>]

v1 -> v2:

 - It was suggested by Daniel Borkmann to extend the neighbor table settings
   rather than adding IPv4/IPv6 options for ARP/NDISC separately. I agree
   this way is much more concise since there is now only one place where the
   option is checked and defined.
 - Moved documentation/code into the same patch
 - Explained in more detail the test scenario and results

v2 -> v3:

 - Renamed 'skip_perm' to 'nocarrier'. The way this parameter is used
   matches this naming.
 - Changed logic to still flush if 'nocarrier' is false.

v3 -> v4:

 - Moved NDTPA_EVICT_NOCARRIER after NDTPA_PAD

v4 -> v5:

 - Went back to the original v1 patchset and changed:
 - Used ANDCONF for IN_DEV macro
 - Got RCU lock prior to __in_dev_get_rcu(). Do note that the logic
   here was extended to handle if __in_dev_get_rcu() fails. If this
   happens the existing behavior should be maintained and set the
   carrier down. I'm unsure if get_rcu() can fail in this context
   though. Similar logic was used for in6_dev_get.
 - Changed ndisc_evict_nocarrier to use a u8, proper handler, and
   set min/max values.


Cc: David S. Miller <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: Ido Schimmel <idosch@nvidia.com>
Cc: Nikolay Aleksandrov <nikolay@nvidia.com>
Cc: Chinmay Agarwal <chinagar@codeaurora.org>
Cc: Yajun Deng <yajun.deng@linux.dev>
Cc: Tong Zhu <zhutong@amazon.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jouni Malinen <jouni@codeaurora.org>

James Prestwood (2):
  net: arp: introduce arp_evict_nocarrier sysctl parameter
  net: ndisc: introduce ndisc_evict_nocarrier sysctl parameter

 Documentation/networking/ip-sysctl.rst | 18 ++++++++++++++++++
 include/linux/inetdevice.h             |  2 ++
 include/linux/ipv6.h                   |  1 +
 include/uapi/linux/ip.h                |  1 +
 include/uapi/linux/ipv6.h              |  1 +
 include/uapi/linux/sysctl.h            |  1 +
 net/ipv4/arp.c                         | 13 ++++++++++++-
 net/ipv4/devinet.c                     |  4 ++++
 net/ipv6/addrconf.c                    | 12 ++++++++++++
 net/ipv6/ndisc.c                       |  5 ++++-
 10 files changed, 56 insertions(+), 2 deletions(-)

-- 
2.31.1