1 files changed, 34 insertions, 19 deletions

diff --git a/net/can/bcm.c b/net/can/bcm.c
index 1e17778d5cee..5cb4b6129263 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -102,6 +102,7 @@ static inline u64 get_u64(const struct canfd_frame *cp, int offset)
 
 struct bcm_op {
 	struct list_head list;
+	struct rcu_head rcu;
 	int ifindex;
 	canid_t can_id;
 	u32 flags;
@@ -275,6 +276,7 @@ static void bcm_can_tx(struct bcm_op *op)
 	struct sk_buff *skb;
 	struct net_device *dev;
 	struct canfd_frame *cf = op->frames + op->cfsiz * op->currframe;
+	int err;
 
 	/* no target device? => exit */
 	if (!op->ifindex)
@@ -299,11 +301,11 @@ static void bcm_can_tx(struct bcm_op *op)
 	/* send with loopback */
 	skb->dev = dev;
 	can_skb_set_owner(skb, op->sk);
-	can_send(skb, 1);
+	err = can_send(skb, 1);
+	if (!err)
+		op->frames_abs++;
 
-	/* update statistics */
 	op->currframe++;
-	op->frames_abs++;
 
 	/* reached last frame? */
 	if (op->currframe >= op->nframes)
@@ -720,10 +722,9 @@ static struct bcm_op *bcm_find_op(struct list_head *ops,
 	return NULL;
 }
 
-static void bcm_remove_op(struct bcm_op *op)
+static void bcm_free_op_rcu(struct rcu_head *rcu_head)
 {
-	hrtimer_cancel(&op->timer);
-	hrtimer_cancel(&op->thrtimer);
+	struct bcm_op *op = container_of(rcu_head, struct bcm_op, rcu);
 
 	if ((op->frames) && (op->frames != &op->sframe))
 		kfree(op->frames);
@@ -734,6 +735,14 @@ static void bcm_remove_op(struct bcm_op *op)
 	kfree(op);
 }
 
+static void bcm_remove_op(struct bcm_op *op)
+{
+	hrtimer_cancel(&op->timer);
+	hrtimer_cancel(&op->thrtimer);
+
+	call_rcu(&op->rcu, bcm_free_op_rcu);
+}
+
 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
 {
 	if (op->rx_reg_dev == dev) {
@@ -759,6 +768,9 @@ static int bcm_delete_rx_op(struct list_head *ops, struct bcm_msg_head *mh,
 		if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) &&
 		    (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME)) {
 
+			/* disable automatic timer on frame reception */
+			op->flags |= RX_NO_AUTOTIMER;
+
 			/*
 			 * Don't care if we're bound or not (due to netdev
 			 * problems) can_rx_unregister() is always a save
@@ -787,7 +799,6 @@ static int bcm_delete_rx_op(struct list_head *ops, struct bcm_msg_head *mh,
 						  bcm_rx_handler, op);
 
 			list_del(&op->list);
-			synchronize_rcu();
 			bcm_remove_op(op);
 			return 1; /* done */
 		}
@@ -927,6 +938,8 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 
 			cf = op->frames + op->cfsiz * i;
 			err = memcpy_from_msg((u8 *)cf, msg, op->cfsiz);
+			if (err < 0)
+				goto free_op;
 
 			if (op->flags & CAN_FD_FRAME) {
 				if (cf->len > 64)
@@ -936,12 +949,8 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 					err = -EINVAL;
 			}
 
-			if (err < 0) {
-				if (op->frames != &op->sframe)
-					kfree(op->frames);
-				kfree(op);
-				return err;
-			}
+			if (err < 0)
+				goto free_op;
 
 			if (msg_head->flags & TX_CP_CAN_ID) {
 				/* copy can_id into frame */
@@ -1012,6 +1021,12 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 		bcm_tx_start_timer(op);
 
 	return msg_head->nframes * op->cfsiz + MHSIZ;
+
+free_op:
+	if (op->frames != &op->sframe)
+		kfree(op->frames);
+	kfree(op);
+	return err;
 }
 
 /*
@@ -1508,6 +1523,12 @@ static int bcm_release(struct socket *sock)
 
 	lock_sock(sk);
 
+#if IS_ENABLED(CONFIG_PROC_FS)
+	/* remove procfs entry */
+	if (net->can.bcmproc_dir && bo->bcm_proc_read)
+		remove_proc_entry(bo->procname, net->can.bcmproc_dir);
+#endif /* CONFIG_PROC_FS */
+
 	list_for_each_entry_safe(op, next, &bo->tx_ops, list)
 		bcm_remove_op(op);
 
@@ -1543,12 +1564,6 @@ static int bcm_release(struct socket *sock)
 	list_for_each_entry_safe(op, next, &bo->rx_ops, list)
 		bcm_remove_op(op);
 
-#if IS_ENABLED(CONFIG_PROC_FS)
-	/* remove procfs entry */
-	if (net->can.bcmproc_dir && bo->bcm_proc_read)
-		remove_proc_entry(bo->procname, net->can.bcmproc_dir);
-#endif /* CONFIG_PROC_FS */
-
 	/* remove device reference */
 	if (bo->bound) {
 		bo->bound   = 0;