[PATCH v1] tty: serial: 8250: 8250_gsc:- Handle return NULL error from ioremap_nocache

[Arvind Yadav]

Here, If ioremap_nocache will fail. It will return NULL.
Kernel can run into a NULL-pointer dereference.
This error check will avoid NULL pointer dereference.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
---
 drivers/tty/serial/8250/8250_gsc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/8250/8250_gsc.c b/drivers/tty/serial/8250/8250_gsc.c
index b1e6ae9..63306de 100644
--- a/drivers/tty/serial/8250/8250_gsc.c
+++ b/drivers/tty/serial/8250/8250_gsc.c
@@ -60,6 +60,10 @@ static int __init serial_init_chip(struct parisc_device *dev)
 					7272727 : 1843200;
 	uart.port.mapbase	= address;
 	uart.port.membase	= ioremap_nocache(address, 16);
+	if (!uart.port.membase) {
+		dev_warn(&dev->dev, "Failed to map memory\n");
+		return -ENOMEM;
+	}
 	uart.port.irq	= dev->irq;
 	uart.port.flags	= UPF_BOOT_AUTOCONF;
 	uart.port.dev	= &dev->dev;
-- 
1.9.1