Re: [PATCH v2 net-next 0/9] neighbour: Add IPv4/IPv6-specific wrappers for neigh_lookup() and friends.

On 10/3/26 11:23 PM, Kuniyuki Iwashima wrote:

syzbot reported that ip6_finish_output2() could pass tbl and dev
from different netns to neigh_create().

When namespacifying neigh_table, I chose to resolve neigh_table
in callers to minimise changes, but it turned out to be error-prone.

This series adds IPv4/IPv6-specific helpers for neigh_lookup()
and neigh_create() that always fetch the netns from dev to fix
the problem.

Along the way, the confusing and now mostly redundant helpers
__neigh_lookup() and __neigh_lookup_errno() are converted and
removed.

Reviewed-by: Fernando Fernandez Mancera <redacted>

Thanks!

Changes:
   v2:
     * Add Patch 9
     * Patch 6 & 7: Convert __teql_resolve()

   v1: https://lore.kernel.org/netdev/20260930200326.718459-1-kuniyu@google.com/ (local)


Kuniyuki Iwashima (9):
   ipv4: Rename ipv4_neigh_lookup() to ipv4_dst_neigh_lookup().
   ipv6: Rename ip6_neigh_lookup() to __ip6_dst_neigh_lookup().
   ipv4: Add wrappers for neigh_lookup() and neigh_create().
   ipv6: Add wrappers for neigh_lookup() and (__)?neigh_create().
   mlxsw: spectrum: Resolve neigh_table right before neigh_lookup().
   ipv6: Use ipv6_neigh_lookup() and friends.
   ipv4: Use ipv4_neigh_lookup() and friends.
   neighbour: Remove __neigh_lookup() and __neigh_lookup_errno().
   neighbour: Check n->parms->tbl under tbl->lock in ___neigh_create().

  .../marvell/prestera/prestera_router.c        | 14 ++--
  .../mellanox/mlx5/core/en/tc_tun_encap.c      | 14 ++--
  .../mellanox/mlx5/core/en_accel/ipsec.c       |  6 +-
  .../ethernet/mellanox/mlxsw/spectrum_router.c | 77 +++++++++++--------
  .../ethernet/mellanox/mlxsw/spectrum_span.c   | 42 ++++++----
  .../netronome/nfp/flower/tunnel_conf.c        |  8 +-
  drivers/net/ethernet/rocker/rocker_ofdpa.c    |  2 +-
  drivers/net/ethernet/sfc/tc_counters.c        | 11 +--
  drivers/net/vrf.c                             |  4 +-
  drivers/net/vxlan/vxlan_core.c                | 14 +---
  include/net/arp.h                             | 16 ++++
  include/net/ip6_route.h                       |  6 +-
  include/net/ndisc.h                           | 31 ++++++--
  include/net/neighbour.h                       | 24 ------
  net/bridge/br_arp_nd_proxy.c                  |  4 +-
  net/core/neighbour.c                          | 11 ++-
  net/ieee802154/6lowpan/tx.c                   |  3 +-
  net/ipv4/arp.c                                | 26 ++++---
  net/ipv4/fib_semantics.c                      |  5 +-
  net/ipv4/route.c                              | 18 ++---
  net/ipv6/ip6_output.c                         |  2 +-
  net/ipv6/ndisc.c                              | 48 +++++++-----
  net/ipv6/route.c                              | 23 +++---
  net/sched/sch_teql.c                          | 15 +++-
  24 files changed, 234 insertions(+), 190 deletions(-)