diff options
| author |   Eric Dumazet <edumazet@google.com> | 2015-03-17 18:32:31 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2015-03-17 22:02:29 -0400 |
| commit | 0470c8ca1d57927f2cc3e1d5add1fb2834609447 (patch) | |
| tree | 798f475f48fbdff0eae359c3f345a1a0eaf83ca2 /include/net/request_sock.h | |
| parent | inet: avoid fastopen lock for regular accept() (diff) | |
| download | linux-dev-0470c8ca1d57927f2cc3e1d5add1fb2834609447.tar.xz linux-dev-0470c8ca1d57927f2cc3e1d5add1fb2834609447.zip | |
inet: fix request sock refcounting
While testing last patch series, I found req sock refcounting was wrong.
We must set skc_refcnt to 1 for all request socks added in hashes,
but also on request sockets created by FastOpen or syncookies.
It is tricky because we need to defer this initialization so that
future RCU lookups do not try to take a refcount on a not yet
fully initialized request socket.
Also get rid of ireq_refcnt alias.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 13854e5a6046 ("inet: add proper refcounting to request sock")
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/request_sock.h')
| -rw-r--r-- | include/net/request_sock.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/include/net/request_sock.h b/include/net/request_sock.h index 723d1cbdf20e..3fa4f824900a 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h @@ -77,6 +77,11 @@ reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener) req->rsk_ops = ops; sock_hold(sk_listener); req->rsk_listener = sk_listener; + + /* Following is temporary. It is coupled with debugging + * helpers in reqsk_put() & reqsk_free() + */ + atomic_set(&req->rsk_refcnt, 0); } return req; } @@ -292,6 +297,12 @@ static inline void reqsk_queue_hash_req(struct request_sock_queue *queue, req->sk = NULL; req->dl_next = lopt->syn_table[hash]; + /* before letting lookups find us, make sure all req fields + * are committed to memory and refcnt initialized. + */ + smp_wmb(); + atomic_set(&req->rsk_refcnt, 1); + write_lock(&queue->syn_wait_lock); lopt->syn_table[hash] = req; write_unlock(&queue->syn_wait_lock); |