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, for now, move the
sctp_put_port() into the sk if body. At a later point in time we
can still determine if there's an option of placing this into
unhash() or sctp_endpoint_free() without any races. For now, leave
it in sctp_endpoint_destroy() though.
Signed-off-by: Daniel Borkmann <dborkman@xxxxxxxxxx>
---
net/sctp/endpointola.c | 18 +++++++++---------
net/sctp/socket.c | 16 +++++++++++++++-
2 files changed, 24 insertions(+), 10 deletions(-)
diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c
index a8b2674..8ad7781 100644
--- a/net/sctp/endpointola.c
+++ b/net/sctp/endpointola.c
@@ -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 +270,14 @@ 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);
+ if ((sk = ep->base.sk)) {
+ /* 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);
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 4c47e55..ba9359c 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -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;
--
1.7.11.7
--
To unsubscribe from this list: send the line "unsubscribe linux-sctp" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
