linux/drivers/tty/serial/8250/8250_gsc.c
Arvind Yadav 2cc32b18d1 tty: serial: 8250: 8250_gsc:- Handle return NULL error from ioremap_nocache
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@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00

135 lines
3.9 KiB
C

/*
* Serial Device Initialisation for Lasi/Asp/Wax/Dino
*
* (c) Copyright Matthew Wilcox <willy@debian.org> 2001-2002
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/serial_core.h>
#include <linux/signal.h>
#include <linux/types.h>
#include <asm/hardware.h>
#include <asm/parisc-device.h>
#include <asm/io.h>
#include "8250.h"
static int __init serial_init_chip(struct parisc_device *dev)
{
struct uart_8250_port uart;
unsigned long address;
int err;
#ifdef CONFIG_64BIT
if (!dev->irq && (dev->id.sversion == 0xad))
dev->irq = iosapic_serial_irq(dev);
#endif
if (!dev->irq) {
/* We find some unattached serial ports by walking native
* busses. These should be silently ignored. Otherwise,
* what we have here is a missing parent device, so tell
* the user what they're missing.
*/
if (parisc_parent(dev)->id.hw_type != HPHW_IOA)
dev_info(&dev->dev,
"Serial: device 0x%llx not configured.\n"
"Enable support for Wax, Lasi, Asp or Dino.\n",
(unsigned long long)dev->hpa.start);
return -ENODEV;
}
address = dev->hpa.start;
if (dev->id.sversion != 0x8d)
address += 0x800;
memset(&uart, 0, sizeof(uart));
uart.port.iotype = UPIO_MEM;
/* 7.272727MHz on Lasi. Assumed the same for Dino, Wax and Timi. */
uart.port.uartclk = (dev->id.sversion != 0xad) ?
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;
err = serial8250_register_8250_port(&uart);
if (err < 0) {
dev_warn(&dev->dev,
"serial8250_register_8250_port returned error %d\n",
err);
iounmap(uart.port.membase);
return err;
}
return 0;
}
static struct parisc_device_id serial_tbl[] = {
{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00075 },
{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0008c },
{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0008d },
{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x000ad },
{ 0 }
};
/* Hack. Some machines have SERIAL_0 attached to Lasi and SERIAL_1
* attached to Dino. Unfortunately, Dino appears before Lasi in the device
* tree. To ensure that ttyS0 == SERIAL_0, we register two drivers; one
* which only knows about Lasi and then a second which will find all the
* other serial ports. HPUX ignores this problem.
*/
static struct parisc_device_id lasi_tbl[] = {
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x03B, 0x0008C }, /* C1xx/C1xxL */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x03C, 0x0008C }, /* B132L */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x03D, 0x0008C }, /* B160L */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x03E, 0x0008C }, /* B132L+ */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x03F, 0x0008C }, /* B180L+ */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x046, 0x0008C }, /* Rocky2 120 */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x047, 0x0008C }, /* Rocky2 150 */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x04E, 0x0008C }, /* Kiji L2 132 */
{ HPHW_FIO, HVERSION_REV_ANY_ID, 0x056, 0x0008C }, /* Raven+ */
{ 0 }
};
MODULE_DEVICE_TABLE(parisc, serial_tbl);
static struct parisc_driver lasi_driver = {
.name = "serial_1",
.id_table = lasi_tbl,
.probe = serial_init_chip,
};
static struct parisc_driver serial_driver = {
.name = "serial",
.id_table = serial_tbl,
.probe = serial_init_chip,
};
static int __init probe_serial_gsc(void)
{
register_parisc_driver(&lasi_driver);
register_parisc_driver(&serial_driver);
return 0;
}
module_init(probe_serial_gsc);
MODULE_LICENSE("GPL");