net: sctp: decouple cleaning some socket data from endpoint

Rather instead of having the endpoint clean the garbage from the
socket, use a sk_destruct handler sctp_destruct_sock(), that does
the job for that when there are no more references on the socket.
At least do this for our crypto transform through crypto_free_hash()
that is allocated when in listening state.

Also, perform sctp_put_port() only when sk is valid. At a later
point in time we can still determine if there's an option of
placing this into sk_prot->unhash() or sctp_endpoint_free() without
any races. For now, leave it in sctp_endpoint_destroy() though.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Borkmann 2013-06-25 18:17:29 +02:00 committed by David S. Miller
parent b527fe6933
commit 0a2fbac197
2 changed files with 25 additions and 10 deletions

View File

@ -247,10 +247,9 @@ void sctp_endpoint_free(struct sctp_endpoint *ep)
/* Final destructor for endpoint. */
static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
{
SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
struct sock *sk;
/* Free up the HMAC transform. */
crypto_free_hash(sctp_sk(ep->base.sk)->hmac);
SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
/* Free the digest buffer */
kfree(ep->digest);
@ -271,13 +270,15 @@ static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
memset(ep->secret_key, 0, sizeof(ep->secret_key));
/* Remove and free the port */
if (sctp_sk(ep->base.sk)->bind_hash)
sctp_put_port(ep->base.sk);
/* Give up our hold on the sock. */
if (ep->base.sk)
sock_put(ep->base.sk);
sk = ep->base.sk;
if (sk != NULL) {
/* Remove and free the port */
if (sctp_sk(sk)->bind_hash)
sctp_put_port(sk);
sock_put(sk);
}
kfree(ep);
SCTP_DBG_OBJCNT_DEC(ep);

View File

@ -93,6 +93,7 @@ static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p);
static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
static int sctp_wait_for_accept(struct sock *sk, long timeo);
static void sctp_wait_for_close(struct sock *sk, long timeo);
static void sctp_destruct_sock(struct sock *sk);
static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
union sctp_addr *addr, int len);
static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
@ -3966,6 +3967,8 @@ static int sctp_init_sock(struct sock *sk)
sp->hmac = NULL;
sk->sk_destruct = sctp_destruct_sock;
SCTP_DBG_OBJCNT_INC(sock);
local_bh_disable();
@ -4008,6 +4011,17 @@ static void sctp_destroy_sock(struct sock *sk)
local_bh_enable();
}
/* Triggered when there are no references on the socket anymore */
static void sctp_destruct_sock(struct sock *sk)
{
struct sctp_sock *sp = sctp_sk(sk);
/* Free up the HMAC transform. */
crypto_free_hash(sp->hmac);
inet_sock_destruct(sk);
}
/* API 4.1.7 shutdown() - TCP Style Syntax
* int shutdown(int socket, int how);
*
@ -6848,7 +6862,7 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
newsk->sk_reuse = sk->sk_reuse;
newsk->sk_shutdown = sk->sk_shutdown;
newsk->sk_destruct = inet_sock_destruct;
newsk->sk_destruct = sctp_destruct_sock;
newsk->sk_family = sk->sk_family;
newsk->sk_protocol = IPPROTO_SCTP;
newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;