serial/arc-uart: Don't index with -ve platform_device->id
probe routine could index into port[] with -ve index. The check in
arc_uart_init_one() was too late.
This came to light when trying to port driver to CONFIG_OF, where
bydefault of-core code sets -ve platform dev id and in absence of
DT serial aliases, driver would use the -ve index.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 3e0b3fa..8089dc3 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -526,15 +526,11 @@
};
static int
-arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
+arc_uart_init_one(struct platform_device *pdev, int dev_id)
{
struct resource *res, *res2;
unsigned long *plat_data;
-
- if (pdev->id < 0 || pdev->id >= CONFIG_SERIAL_ARC_NR_PORTS) {
- dev_err(&pdev->dev, "Wrong uart platform device id.\n");
- return -ENOENT;
- }
+ struct arc_uart_port *uart = &arc_uart_ports[dev_id];
plat_data = ((unsigned long *)(pdev->dev.platform_data));
uart->baud = plat_data[0];
@@ -557,7 +553,7 @@
uart->port.dev = &pdev->dev;
uart->port.iotype = UPIO_MEM;
uart->port.flags = UPF_BOOT_AUTOCONF;
- uart->port.line = pdev->id;
+ uart->port.line = dev_id;
uart->port.ops = &arc_serial_pops;
uart->port.uartclk = plat_data[1];
@@ -657,9 +653,14 @@
static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
{
- arc_early_serial_console.index = pdev->id;
+ int dev_id = pdev->id < 0 ? 0 : pdev->id;
+ int rc;
- arc_uart_init_one(pdev, &arc_uart_ports[pdev->id]);
+ arc_early_serial_console.index = dev_id;
+
+ rc = arc_uart_init_one(pdev, dev_id);
+ if (rc)
+ panic("early console init failed\n");
arc_serial_console_setup(&arc_early_serial_console, NULL);
@@ -675,18 +676,18 @@
static int arc_serial_probe(struct platform_device *pdev)
{
- struct arc_uart_port *uart;
- int rc;
+ int rc, dev_id;
if (is_early_platform_device(pdev))
return arc_serial_probe_earlyprintk(pdev);
- uart = &arc_uart_ports[pdev->id];
- rc = arc_uart_init_one(pdev, uart);
+ dev_id = pdev->id < 0 ? 0 : pdev->id;
+ rc = arc_uart_init_one(pdev, dev_id);
if (rc)
return rc;
- return uart_add_one_port(&arc_uart_driver, &uart->port);
+ rc = uart_add_one_port(&arc_uart_driver, &arc_uart_ports[dev_id].port);
+ return rc;
}
static int arc_serial_remove(struct platform_device *pdev)