[v3,net,00/16] net: first round to use dev_net_rcu()

Message

Eric Dumazet Feb. 4, 2025, 1:23 p.m. UTC

dev_net(dev) should either be protected by RTNL or RCU.

There is no LOCKDEP support yet for this helper.

Adding it would trigger too many splats.

Instead, add dev_net_rcu() and start to use it
to either fix bugs or document points that were safely
using dev_net() in rcu_read_lock() sections.

v3: Rework patches 9 and 10 after Jakub feedback.
    Link: https://lore.kernel.org/netdev/[e-mail]/
    Added some missing Fixes tags.

v2: Resend (one patch missed v1 train), plus minor fixes.

Eric Dumazet (16):
  net: add dev_net_rcu() helper
  ipv4: add RCU protection to ip4_dst_hoplimit()
  ipv4: use RCU protection in ip_dst_mtu_maybe_forward()
  ipv4: use RCU protection in ipv4_default_advmss()
  ipv4: use RCU protection in rt_is_expired()
  tcp: convert to dev_net_rcu()
  net: gro: convert four dev_net() calls
  udp: convert to dev_net_rcu()
  ipv4: icmp: convert to dev_net_rcu()
  ipv6: icmp: convert to dev_net_rcu()
  ipv6: input: convert to dev_net_rcu()
  ipv6: output: convert to dev_net_rcu()
  ipv6: use RCU protection in ip6_default_advmss()
  net: filter: convert to dev_net_rcu()
  flow_dissector: use rcu protection to fetch dev_net()
  ipv4: use RCU protection in inet_select_addr()

 include/linux/netdevice.h      |  6 +++++
 include/net/inet6_hashtables.h |  2 +-
 include/net/inet_hashtables.h  |  2 +-
 include/net/ip.h               | 13 ++++++++---
 include/net/net_namespace.h    |  2 +-
 include/net/route.h            |  9 ++++++--
 net/core/filter.c              | 40 ++++++++++++++++----------------
 net/core/flow_dissector.c      | 21 +++++++++--------
 net/ipv4/devinet.c             |  3 ++-
 net/ipv4/icmp.c                | 31 +++++++++++++------------
 net/ipv4/route.c               | 19 +++++++++++----
 net/ipv4/tcp_ipv4.c            |  8 +++----
 net/ipv4/tcp_metrics.c         |  6 ++---
 net/ipv4/tcp_offload.c         |  2 +-
 net/ipv4/udp.c                 | 19 +++++++--------
 net/ipv4/udp_offload.c         |  2 +-
 net/ipv6/icmp.c                | 42 +++++++++++++++++++---------------
 net/ipv6/ip6_input.c           | 12 +++++-----
 net/ipv6/ip6_output.c          |  4 ++--
 net/ipv6/output_core.c         |  2 +-
 net/ipv6/route.c               |  7 +++++-
 net/ipv6/tcp_ipv6.c            | 10 ++++----
 net/ipv6/tcpv6_offload.c       |  2 +-
 net/ipv6/udp.c                 | 18 +++++++--------
 net/ipv6/udp_offload.c         |  2 +-
 25 files changed, 164 insertions(+), 120 deletions(-)