From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arvind Yadav Subject: [PATCH v1] tty: serial: 8250: 8250_gsc:- Handle return NULL error from ioremap_nocache Date: Thu, 19 Jan 2017 13:30:44 +0530 Message-ID: <1484812844-10598-1-git-send-email-arvind.yadav.cs@gmail.com> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: jejb@parisc-linux.org, deller@gmx.de, gregkh@linuxfoundation.org Cc: jslaby@suse.com, linux-parisc@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-serial@vger.kernel.org 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 --- 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