Merge tag 'linux-can-fixes-for-5.15-20211017' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2021-10-17

this is a pull request of 11 patches for net/master.

The first 4 patches are by Ziyang Xuan and Zhang Changzhong and fix 1
use after free and 3 standard conformance problems in the j1939 CAN
stack.

The next 2 patches are by Ziyang Xuan and fix 2 concurrency problems
in the ISOTP CAN stack.

Yoshihiro Shimoda's patch for the rcar_can fix suspend/resume on not
running CAN interfaces.

Aswath Govindraju's patch for the m_can driver fixes access for MMIO
devices.

Zheyu Ma contributes a patch for the peak_pci driver to fix a use
after free.

Stephane Grosjean's 2 patches fix CAN error state handling in the
peak_usb driver.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 79 insertions, 42 deletions

diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
index 308d4f2fff00..eee47bad0592 100644
--- a/drivers/net/can/m_can/m_can_platform.c
+++ b/drivers/net/can/m_can/m_can_platform.c
@@ -32,8 +32,13 @@ static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
 static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
 {
 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
+	void __iomem *src = priv->mram_base + offset;
 
-	ioread32_rep(priv->mram_base + offset, val, val_count);
+	while (val_count--) {
+		*(unsigned int *)val = ioread32(src);
+		val += 4;
+		src += 4;
+	}
 
 	return 0;
 }
@@ -51,8 +56,13 @@ static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
 			    const void *val, size_t val_count)
 {
 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
+	void __iomem *dst = priv->mram_base + offset;
 
-	iowrite32_rep(priv->base + offset, val, val_count);
+	while (val_count--) {
+		iowrite32(*(unsigned int *)val, dst);
+		val += 4;
+		dst += 4;
+	}
 
 	return 0;
 }
diff --git a/drivers/net/can/rcar/rcar_can.c b/drivers/net/can/rcar/rcar_can.c
index 00e4533c8bdd..8999ec9455ec 100644
--- a/drivers/net/can/rcar/rcar_can.c
+++ b/drivers/net/can/rcar/rcar_can.c
@@ -846,10 +846,12 @@ static int __maybe_unused rcar_can_suspend(struct device *dev)
 	struct rcar_can_priv *priv = netdev_priv(ndev);
 	u16 ctlr;
 
-	if (netif_running(ndev)) {
-		netif_stop_queue(ndev);
-		netif_device_detach(ndev);
-	}
+	if (!netif_running(ndev))
+		return 0;
+
+	netif_stop_queue(ndev);
+	netif_device_detach(ndev);
+
 	ctlr = readw(&priv->regs->ctlr);
 	ctlr |= RCAR_CAN_CTLR_CANM_HALT;
 	writew(ctlr, &priv->regs->ctlr);
@@ -868,6 +870,9 @@ static int __maybe_unused rcar_can_resume(struct device *dev)
 	u16 ctlr;
 	int err;
 
+	if (!netif_running(ndev))
+		return 0;
+
 	err = clk_enable(priv->clk);
 	if (err) {
 		netdev_err(ndev, "clk_enable() failed, error %d\n", err);
@@ -881,10 +886,9 @@ static int __maybe_unused rcar_can_resume(struct device *dev)
 	writew(ctlr, &priv->regs->ctlr);
 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 
-	if (netif_running(ndev)) {
-		netif_device_attach(ndev);
-		netif_start_queue(ndev);
-	}
+	netif_device_attach(ndev);
+	netif_start_queue(ndev);
+
 	return 0;
 }
 
diff --git a/drivers/net/can/sja1000/peak_pci.c b/drivers/net/can/sja1000/peak_pci.c
index 6db90dc4bc9d..84f34020aafb 100644
--- a/drivers/net/can/sja1000/peak_pci.c
+++ b/drivers/net/can/sja1000/peak_pci.c
@@ -752,16 +752,15 @@ static void peak_pci_remove(struct pci_dev *pdev)
 		struct net_device *prev_dev = chan->prev_dev;
 
 		dev_info(&pdev->dev, "removing device %s\n", dev->name);
+		/* do that only for first channel */
+		if (!prev_dev && chan->pciec_card)
+			peak_pciec_remove(chan->pciec_card);
 		unregister_sja1000dev(dev);
 		free_sja1000dev(dev);
 		dev = prev_dev;
 
-		if (!dev) {
-			/* do that only for first channel */
-			if (chan->pciec_card)
-				peak_pciec_remove(chan->pciec_card);
+		if (!dev)
 			break;
-		}
 		priv = netdev_priv(dev);
 		chan = priv->priv;
 	}
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c
index b11eabad575b..09029a3bad1a 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c
@@ -551,11 +551,10 @@ static int pcan_usb_fd_decode_status(struct pcan_usb_fd_if *usb_if,
 	} else if (sm->channel_p_w_b & PUCAN_BUS_WARNING) {
 		new_state = CAN_STATE_ERROR_WARNING;
 	} else {
-		/* no error bit (so, no error skb, back to active state) */
-		dev->can.state = CAN_STATE_ERROR_ACTIVE;
+		/* back to (or still in) ERROR_ACTIVE state */
+		new_state = CAN_STATE_ERROR_ACTIVE;
 		pdev->bec.txerr = 0;
 		pdev->bec.rxerr = 0;
-		return 0;
 	}
 
 	/* state hasn't changed */
@@ -568,8 +567,7 @@ static int pcan_usb_fd_decode_status(struct pcan_usb_fd_if *usb_if,
 
 	/* allocate an skb to store the error frame */
 	skb = alloc_can_err_skb(netdev, &cf);
-	if (skb)
-		can_change_state(netdev, cf, tx_state, rx_state);
+	can_change_state(netdev, cf, tx_state, rx_state);
 
 	/* things must be done even in case of OOM */
 	if (new_state == CAN_STATE_BUS_OFF)
diff --git a/net/can/isotp.c b/net/can/isotp.c
index caaa532ece94..d1f54273c0bb 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -121,7 +121,7 @@ enum {
 struct tpcon {
 	int idx;
 	int len;
-	u8 state;
+	u32 state;
 	u8 bs;
 	u8 sn;
 	u8 ll_dl;
@@ -848,6 +848,7 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 {
 	struct sock *sk = sock->sk;
 	struct isotp_sock *so = isotp_sk(sk);
+	u32 old_state = so->tx.state;
 	struct sk_buff *skb;
 	struct net_device *dev;
 	struct canfd_frame *cf;
@@ -860,45 +861,55 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 		return -EADDRNOTAVAIL;
 
 	/* we do not support multiple buffers - for now */
-	if (so->tx.state != ISOTP_IDLE || wq_has_sleeper(&so->wait)) {
-		if (msg->msg_flags & MSG_DONTWAIT)
-			return -EAGAIN;
+	if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE ||
+	    wq_has_sleeper(&so->wait)) {
+		if (msg->msg_flags & MSG_DONTWAIT) {
+			err = -EAGAIN;
+			goto err_out;
+		}
 
 		/* wait for complete transmission of current pdu */
-		wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+		err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+		if (err)
+			goto err_out;
 	}
 
-	if (!size || size > MAX_MSG_LENGTH)
-		return -EINVAL;
+	if (!size || size > MAX_MSG_LENGTH) {
+		err = -EINVAL;
+		goto err_out;
+	}
 
 	/* take care of a potential SF_DL ESC offset for TX_DL > 8 */
 	off = (so->tx.ll_dl > CAN_MAX_DLEN) ? 1 : 0;
 
 	/* does the given data fit into a single frame for SF_BROADCAST? */
 	if ((so->opt.flags & CAN_ISOTP_SF_BROADCAST) &&
-	    (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off))
-		return -EINVAL;
+	    (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off)) {
+		err = -EINVAL;
+		goto err_out;
+	}
 
 	err = memcpy_from_msg(so->tx.buf, msg, size);
 	if (err < 0)
-		return err;
+		goto err_out;
 
 	dev = dev_get_by_index(sock_net(sk), so->ifindex);
-	if (!dev)
-		return -ENXIO;
+	if (!dev) {
+		err = -ENXIO;
+		goto err_out;
+	}
 
 	skb = sock_alloc_send_skb(sk, so->ll.mtu + sizeof(struct can_skb_priv),
 				  msg->msg_flags & MSG_DONTWAIT, &err);
 	if (!skb) {
 		dev_put(dev);
-		return err;
+		goto err_out;
 	}
 
 	can_skb_reserve(skb);
 	can_skb_prv(skb)->ifindex = dev->ifindex;
 	can_skb_prv(skb)->skbcnt = 0;
 
-	so->tx.state = ISOTP_SENDING;
 	so->tx.len = size;
 	so->tx.idx = 0;
 
@@ -954,7 +965,7 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	if (err) {
 		pr_notice_once("can-isotp: %s: can_send_ret %pe\n",
 			       __func__, ERR_PTR(err));
-		return err;
+		goto err_out;
 	}
 
 	if (wait_tx_done) {
@@ -963,6 +974,13 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	}
 
 	return size;
+
+err_out:
+	so->tx.state = old_state;
+	if (so->tx.state == ISOTP_IDLE)
+		wake_up_interruptible(&so->wait);
+
+	return err;
 }
 
 static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
diff --git a/net/can/j1939/j1939-priv.h b/net/can/j1939/j1939-priv.h
index f6df20808f5e..16af1a7f80f6 100644
--- a/net/can/j1939/j1939-priv.h
+++ b/net/can/j1939/j1939-priv.h
@@ -330,6 +330,7 @@ int j1939_session_activate(struct j1939_session *session);
 void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec);
 void j1939_session_timers_cancel(struct j1939_session *session);
 
+#define J1939_MIN_TP_PACKET_SIZE 9
 #define J1939_MAX_TP_PACKET_SIZE (7 * 0xff)
 #define J1939_MAX_ETP_PACKET_SIZE (7 * 0x00ffffff)
 
diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c
index 08c8606cfd9c..9bc55ecb37f9 100644
--- a/net/can/j1939/main.c
+++ b/net/can/j1939/main.c
@@ -249,11 +249,14 @@ struct j1939_priv *j1939_netdev_start(struct net_device *ndev)
 	struct j1939_priv *priv, *priv_new;
 	int ret;
 
-	priv = j1939_priv_get_by_ndev(ndev);
+	spin_lock(&j1939_netdev_lock);
+	priv = j1939_priv_get_by_ndev_locked(ndev);
 	if (priv) {
 		kref_get(&priv->rx_kref);
+		spin_unlock(&j1939_netdev_lock);
 		return priv;
 	}
+	spin_unlock(&j1939_netdev_lock);
 
 	priv = j1939_priv_create(ndev);
 	if (!priv)
@@ -269,10 +272,10 @@ struct j1939_priv *j1939_netdev_start(struct net_device *ndev)
 		/* Someone was faster than us, use their priv and roll
 		 * back our's.
 		 */
+		kref_get(&priv_new->rx_kref);
 		spin_unlock(&j1939_netdev_lock);
 		dev_put(ndev);
 		kfree(priv);
-		kref_get(&priv_new->rx_kref);
 		return priv_new;
 	}
 	j1939_priv_set(ndev, priv);
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index bb5c4b8979be..6c0a0ebdd024 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1237,12 +1237,11 @@ static enum hrtimer_restart j1939_tp_rxtimer(struct hrtimer *hrtimer)
 		session->err = -ETIME;
 		j1939_session_deactivate(session);
 	} else {
-		netdev_alert(priv->ndev, "%s: 0x%p: rx timeout, send abort\n",
-			     __func__, session);
-
 		j1939_session_list_lock(session->priv);
 		if (session->state >= J1939_SESSION_ACTIVE &&
 		    session->state < J1939_SESSION_ACTIVE_MAX) {
+			netdev_alert(priv->ndev, "%s: 0x%p: rx timeout, send abort\n",
+				     __func__, session);
 			j1939_session_get(session);
 			hrtimer_start(&session->rxtimer,
 				      ms_to_ktime(J1939_XTP_ABORT_TIMEOUT_MS),
@@ -1609,6 +1608,8 @@ j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv,
 			abort = J1939_XTP_ABORT_FAULT;
 		else if (len > priv->tp_max_packet_size)
 			abort = J1939_XTP_ABORT_RESOURCE;
+		else if (len < J1939_MIN_TP_PACKET_SIZE)
+			abort = J1939_XTP_ABORT_FAULT;
 	}
 
 	if (abort != J1939_XTP_NO_ABORT) {
@@ -1789,6 +1790,7 @@ static void j1939_xtp_rx_dpo(struct j1939_priv *priv, struct sk_buff *skb,
 static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 				 struct sk_buff *skb)
 {
+	enum j1939_xtp_abort abort = J1939_XTP_ABORT_FAULT;
 	struct j1939_priv *priv = session->priv;
 	struct j1939_sk_buff_cb *skcb, *se_skcb;
 	struct sk_buff *se_skb = NULL;
@@ -1803,9 +1805,11 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 
 	skcb = j1939_skb_to_cb(skb);
 	dat = skb->data;
-	if (skb->len <= 1)
+	if (skb->len != 8) {
 		/* makes no sense */
+		abort = J1939_XTP_ABORT_UNEXPECTED_DATA;
 		goto out_session_cancel;
+	}
 
 	switch (session->last_cmd) {
 	case 0xff:
@@ -1904,7 +1908,7 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
  out_session_cancel:
 	kfree_skb(se_skb);
 	j1939_session_timers_cancel(session);
-	j1939_session_cancel(session, J1939_XTP_ABORT_FAULT);
+	j1939_session_cancel(session, abort);
 	j1939_session_put(session);
 }