[PATCH net v3 0/2] net: gro: add flush/flush_id checks and fix wrong offset in udp

[Richard Gobert <richardbgobert@gmail.com>]

This series fixes a bug in the complete phase of UDP in GRO, in which
socket lookup fails due to using network_header when parsing encapsulated
packets. The fix is to add network_offset and inner_network_offset to
napi_gro_cb and use these offsets for socket lookup.

In addition, p->flush/flush_id should be checked in all UDP flows. The 
same logic from tcp_gro_receive is applied for all flows in
udp_gro_receive_segment. This prevents packets with mismatching network
headers (flush/flush_id turned on) from merging in UDP GRO.

The original series includes a change to vxlan test which adds the local
parameter to prevent similar future bugs. I plan to submit it separately to
net-next.

This series is part of a previously submitted series to net-next:
https://lore.kernel.org/all/20240408141720.98832-1-richardbgobert@gmail.com/

v2 -> v3:
 - Add network_offsets and fix udp bug in a single commit to make backporting easier
 - Write to inner_network_offset in {inet,ipv6}_gro_receive
 - Use network_offsets union in tcp[46]_gro_complete as well
 - v2:
 https://lore.kernel.org/netdev/20240419153542.121087-1-richardbgobert@gmail.com/

v1 -> v2:
 - Use network_offsets instead of p_poff param as suggested by Willem
 - Check flush before postpull, and for all UDP GRO flows
 - v1:
 https://lore.kernel.org/netdev/20240412152120.115067-1-richardbgobert@gmail.com/

Richard Gobert (2):
  net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb
  net: gro: add flush check in udp_gro_receive_segment

 include/net/gro.h        | 18 ++++++++++++++++--
 net/8021q/vlan_core.c    |  2 ++
 net/core/gro.c           |  1 +
 net/ipv4/af_inet.c       |  5 +----
 net/ipv4/tcp_offload.c   |  3 ++-
 net/ipv4/udp.c           |  3 ++-
 net/ipv4/udp_offload.c   | 15 +++++++++++++--
 net/ipv6/ip6_offload.c   |  6 +++---
 net/ipv6/tcpv6_offload.c |  3 ++-
 net/ipv6/udp.c           |  3 ++-
 net/ipv6/udp_offload.c   |  3 ++-
 11 files changed, 46 insertions(+), 16 deletions(-)

-- 
2.36.1