[PATCH net-next v1 0/3] net: Avoid ehash lookup races

[xuanqiang.luo@linux.dev]

From: Xuanqiang Luo <luoxuanqiang@kylinos.cn>

After replacing R/W locks with RCU in commit 3ab5aee7fe84 ("net: Convert
TCP & DCCP hash tables to use RCU / hlist_nulls"), a race window emerged
during the switch from reqsk/sk to sk/tw.

Now that both timewait sock (tw) and full sock (sk) reside on the same ehash
chain, it is appropriate to introduce hlist_nulls replace operations, to
eliminate the race conditions caused by this window.

Xuanqiang Luo (3):
  rculist: Add __hlist_nulls_replace_rcu() and
    hlist_nulls_replace_init_rcu()
  inet: Avoid ehash lookup race in inet_ehash_insert()
  inet: Avoid ehash lookup race in inet_twsk_hashdance_schedule()

 include/linux/rculist_nulls.h | 62 +++++++++++++++++++++++++++++++++++
 include/net/sock.h            | 23 +++++++++++++
 net/ipv4/inet_hashtables.c    |  7 ++++
 net/ipv4/inet_timewait_sock.c | 20 ++++++-----
 4 files changed, 103 insertions(+), 9 deletions(-)

-- 
2.27.0