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Diffstat (limited to 'net/can/j1939/socket.c')
-rw-r--r--net/can/j1939/socket.c103
1 files changed, 81 insertions, 22 deletions
diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c
index 37c1040bcb9c..de09b0a65791 100644
--- a/net/can/j1939/socket.c
+++ b/net/can/j1939/socket.c
@@ -78,7 +78,6 @@ static void j1939_jsk_add(struct j1939_priv *priv, struct j1939_sock *jsk)
{
jsk->state |= J1939_SOCK_BOUND;
j1939_priv_get(priv);
- jsk->priv = priv;
spin_lock_bh(&priv->j1939_socks_lock);
list_add_tail(&jsk->list, &priv->j1939_socks);
@@ -91,7 +90,6 @@ static void j1939_jsk_del(struct j1939_priv *priv, struct j1939_sock *jsk)
list_del_init(&jsk->list);
spin_unlock_bh(&priv->j1939_socks_lock);
- jsk->priv = NULL;
j1939_priv_put(priv);
jsk->state &= ~J1939_SOCK_BOUND;
}
@@ -349,6 +347,34 @@ void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb)
spin_unlock_bh(&priv->j1939_socks_lock);
}
+static void j1939_sk_sock_destruct(struct sock *sk)
+{
+ struct j1939_sock *jsk = j1939_sk(sk);
+
+ /* This function will be call by the generic networking code, when then
+ * the socket is ultimately closed (sk->sk_destruct).
+ *
+ * The race between
+ * - processing a received CAN frame
+ * (can_receive -> j1939_can_recv)
+ * and accessing j1939_priv
+ * ... and ...
+ * - closing a socket
+ * (j1939_can_rx_unregister -> can_rx_unregister)
+ * and calling the final j1939_priv_put()
+ *
+ * is avoided by calling the final j1939_priv_put() from this
+ * RCU deferred cleanup call.
+ */
+ if (jsk->priv) {
+ j1939_priv_put(jsk->priv);
+ jsk->priv = NULL;
+ }
+
+ /* call generic CAN sock destruct */
+ can_sock_destruct(sk);
+}
+
static int j1939_sk_init(struct sock *sk)
{
struct j1939_sock *jsk = j1939_sk(sk);
@@ -371,6 +397,7 @@ static int j1939_sk_init(struct sock *sk)
atomic_set(&jsk->skb_pending, 0);
spin_lock_init(&jsk->sk_session_queue_lock);
INIT_LIST_HEAD(&jsk->sk_session_queue);
+ sk->sk_destruct = j1939_sk_sock_destruct;
return 0;
}
@@ -443,6 +470,12 @@ static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
}
jsk->ifindex = addr->can_ifindex;
+
+ /* the corresponding j1939_priv_put() is called via
+ * sk->sk_destruct, which points to j1939_sk_sock_destruct()
+ */
+ j1939_priv_get(priv);
+ jsk->priv = priv;
}
/* set default transmit pgn */
@@ -560,8 +593,8 @@ static int j1939_sk_release(struct socket *sock)
if (!sk)
return 0;
- jsk = j1939_sk(sk);
lock_sock(sk);
+ jsk = j1939_sk(sk);
if (jsk->state & J1939_SOCK_BOUND) {
struct j1939_priv *priv = jsk->priv;
@@ -580,6 +613,7 @@ static int j1939_sk_release(struct socket *sock)
j1939_netdev_stop(priv);
}
+ kfree(jsk->filters);
sock_orphan(sk);
sock->sk = NULL;
@@ -909,8 +943,10 @@ void j1939_sk_errqueue(struct j1939_session *session,
memset(serr, 0, sizeof(*serr));
switch (type) {
case J1939_ERRQUEUE_ACK:
- if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK))
+ if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)) {
+ kfree_skb(skb);
return;
+ }
serr->ee.ee_errno = ENOMSG;
serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
@@ -918,8 +954,10 @@ void j1939_sk_errqueue(struct j1939_session *session,
state = "ACK";
break;
case J1939_ERRQUEUE_SCHED:
- if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED))
+ if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)) {
+ kfree_skb(skb);
return;
+ }
serr->ee.ee_errno = ENOMSG;
serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
@@ -1054,51 +1092,72 @@ static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg,
{
struct sock *sk = sock->sk;
struct j1939_sock *jsk = j1939_sk(sk);
- struct j1939_priv *priv = jsk->priv;
+ struct j1939_priv *priv;
int ifindex;
int ret;
+ lock_sock(sock->sk);
/* various socket state tests */
- if (!(jsk->state & J1939_SOCK_BOUND))
- return -EBADFD;
+ if (!(jsk->state & J1939_SOCK_BOUND)) {
+ ret = -EBADFD;
+ goto sendmsg_done;
+ }
+ priv = jsk->priv;
ifindex = jsk->ifindex;
- if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR)
+ if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) {
/* no source address assigned yet */
- return -EBADFD;
+ ret = -EBADFD;
+ goto sendmsg_done;
+ }
/* deal with provided destination address info */
if (msg->msg_name) {
struct sockaddr_can *addr = msg->msg_name;
- if (msg->msg_namelen < J1939_MIN_NAMELEN)
- return -EINVAL;
+ if (msg->msg_namelen < J1939_MIN_NAMELEN) {
+ ret = -EINVAL;
+ goto sendmsg_done;
+ }
- if (addr->can_family != AF_CAN)
- return -EINVAL;
+ if (addr->can_family != AF_CAN) {
+ ret = -EINVAL;
+ goto sendmsg_done;
+ }
- if (addr->can_ifindex && addr->can_ifindex != ifindex)
- return -EBADFD;
+ if (addr->can_ifindex && addr->can_ifindex != ifindex) {
+ ret = -EBADFD;
+ goto sendmsg_done;
+ }
if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
- !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn))
- return -EINVAL;
+ !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) {
+ ret = -EINVAL;
+ goto sendmsg_done;
+ }
if (!addr->can_addr.j1939.name &&
addr->can_addr.j1939.addr == J1939_NO_ADDR &&
- !sock_flag(sk, SOCK_BROADCAST))
+ !sock_flag(sk, SOCK_BROADCAST)) {
/* broadcast, but SO_BROADCAST not set */
- return -EACCES;
+ ret = -EACCES;
+ goto sendmsg_done;
+ }
} else {
if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR &&
- !sock_flag(sk, SOCK_BROADCAST))
+ !sock_flag(sk, SOCK_BROADCAST)) {
/* broadcast, but SO_BROADCAST not set */
- return -EACCES;
+ ret = -EACCES;
+ goto sendmsg_done;
+ }
}
ret = j1939_sk_send_loop(priv, sk, msg, size);
+sendmsg_done:
+ release_sock(sock->sk);
+
return ret;
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.