Merge tag 'tty-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some tty and serial driver fixes for 5.7-rc3.

  The "largest" in here are a number of reverts for previous changes to
  the uartps serial driver that turned out to not be a good idea at all.

  The others are just small fixes found by people and tools. Included in
  here is a much-reported symbol export needed by previous changes that
  happened in 5.7-rc1. All of these have been in linux-next for a while
  with no reported issues"

* tag 'tty-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: hvc: fix buffer overflow during hvc_alloc().
  tty: rocket, avoid OOB access
  tty: serial: bcm63xx: fix missing clk_put() in bcm63xx_uart
  vt: don't hardcode the mem allocation upper bound
  tty: serial: owl: add "much needed" clk_prepare_enable()
  vt: don't use kmalloc() for the unicode screen buffer
  tty/sysrq: Export sysrq_mask(), sysrq_toggle_support()
  serial: sh-sci: Make sure status register SCxSR is read in correct sequence
  serial: sunhv: Initialize lock for non-registered console
  Revert "serial: uartps: Register own uart console and driver structures"
  Revert "serial: uartps: Move Port ID to device data structure"
  Revert "serial: uartps: Change uart ID port allocation"
  Revert "serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES"
  Revert "serial: uartps: Fix error path when alloc failed"
  Revert "serial: uartps: Use the same dynamic major number for all ports"
  Revert "serial: uartps: Fix uartps_major handling"

Author: torvalds

drivers/tty/hvc/hvc_console.c

@@ -302,10 +302,6 @@ int hvc_instantiate(uint32_t vtermno, int index, const struct hv_ops *ops)
 	vtermnos[index] = vtermno;
 	cons_ops[index] = ops;
 
-	/* reserve all indices up to and including this index */
-	if (last_hvc < index)
-		last_hvc = index;
-
 	/* check if we need to re-register the kernel console */
 	hvc_check_console(index);
 
@@ -960,13 +956,22 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 		    cons_ops[i] == hp->ops)
 			break;
 
-	/* no matching slot, just use a counter */
-	if (i >= MAX_NR_HVC_CONSOLES)
-		i = ++last_hvc;
+	if (i >= MAX_NR_HVC_CONSOLES) {
+
+		/* find 'empty' slot for console */
+		for (i = 0; i < MAX_NR_HVC_CONSOLES && vtermnos[i] != -1; i++) {
+		}
+
+		/* no matching slot, just use a counter */
+		if (i == MAX_NR_HVC_CONSOLES)
+			i = ++last_hvc + MAX_NR_HVC_CONSOLES;
+	}
 
 	hp->index = i;
-	cons_ops[i] = ops;
-	vtermnos[i] = vtermno;
+	if (i < MAX_NR_HVC_CONSOLES) {
+		cons_ops[i] = ops;
+		vtermnos[i] = vtermno;
+	}
 
 	list_add_tail(&(hp->next), &hvc_structs);
 	mutex_unlock(&hvc_structs_mutex);

drivers/tty/rocket.c

@@ -632,18 +632,21 @@ init_r_port(int board, int aiop, int chan, struct pci_dev *pci_dev)
 	tty_port_init(&info->port);
 	info->port.ops = &rocket_port_ops;
 	info->flags &= ~ROCKET_MODE_MASK;
-	switch (pc104[board][line]) {
-	case 422:
-		info->flags |= ROCKET_MODE_RS422;
-		break;
-	case 485:
-		info->flags |= ROCKET_MODE_RS485;
-		break;
-	case 232:
-	default:
+	if (board < ARRAY_SIZE(pc104) && line < ARRAY_SIZE(pc104_1))
+		switch (pc104[board][line]) {
+		case 422:
+			info->flags |= ROCKET_MODE_RS422;
+			break;
+		case 485:
+			info->flags |= ROCKET_MODE_RS485;
+			break;
+		case 232:
+		default:
+			info->flags |= ROCKET_MODE_RS232;
+			break;
+		}
+	else
 		info->flags |= ROCKET_MODE_RS232;
-		break;
-	}
 
 	info->intmask = RXF_TRIG | TXFIFO_MT | SRC_INT | DELTA_CD | DELTA_CTS | DELTA_DSR;
 	if (sInitChan(ctlp, &info->channel, aiop, chan) == 0) {

drivers/tty/serial/bcm63xx_uart.c

@@ -843,8 +843,10 @@ static int bcm_uart_probe(struct platform_device *pdev)
 	if (IS_ERR(clk) && pdev->dev.of_node)
 		clk = of_clk_get(pdev->dev.of_node, 0);
 
-	if (IS_ERR(clk))
+	if (IS_ERR(clk)) {
+		clk_put(clk);
 		return -ENODEV;
+	}
 
 	port->iotype = UPIO_MEM;
 	port->irq = res_irq->start;

drivers/tty/serial/owl-uart.c

@@ -680,6 +680,12 @@ static int owl_uart_probe(struct platform_device *pdev)
 		return PTR_ERR(owl_port->clk);
 	}
 
+	ret = clk_prepare_enable(owl_port->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "could not enable clk\n");
+		return ret;
+	}
+
 	owl_port->port.dev = &pdev->dev;
 	owl_port->port.line = pdev->id;
 	owl_port->port.type = PORT_OWL;
@@ -712,6 +718,7 @@ static int owl_uart_remove(struct platform_device *pdev)
 
 	uart_remove_one_port(&owl_uart_driver, &owl_port->port);
 	owl_uart_ports[pdev->id] = NULL;
+	clk_disable_unprepare(owl_port->clk);
 
 	return 0;
 }

drivers/tty/serial/sh-sci.c

@@ -870,9 +870,16 @@ static void sci_receive_chars(struct uart_port *port)
 				tty_insert_flip_char(tport, c, TTY_NORMAL);
 		} else {
 			for (i = 0; i < count; i++) {
-				char c = serial_port_in(port, SCxRDR);
-
-				status = serial_port_in(port, SCxSR);
+				char c;
+
+				if (port->type == PORT_SCIF ||
+				    port->type == PORT_HSCIF) {
+					status = serial_port_in(port, SCxSR);
+					c = serial_port_in(port, SCxRDR);
+				} else {
+					c = serial_port_in(port, SCxRDR);
+					status = serial_port_in(port, SCxSR);
+				}
 				if (uart_handle_sysrq_char(port, c)) {
 					count--; i--;
 					continue;

drivers/tty/serial/sunhv.c

@@ -567,6 +567,9 @@ static int hv_probe(struct platform_device *op)
 	sunserial_console_match(&sunhv_console, op->dev.of_node,
 				&sunhv_reg, port->line, false);
 
+	/* We need to initialize lock even for non-registered console */
+	spin_lock_init(&port->lock);
+
 	err = uart_add_one_port(&sunhv_reg, port);
 	if (err)
 		goto out_unregister_driver;