From f561b4230cec90137baeba1b1c9302461939b870 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Thu, 6 Mar 2014 10:31:16 +0100 Subject: gpio: max732x: Fix possible NULL pointer dereference on i2c_new_dummy error In max732x_probe() driver allocates dummy I2C device (if number of ports is greater than 8) with i2c_new_dummy() but it does not check the return value of this call. In case of error (i2c_new_device(): memory allocation failure or I2C address cannot be used) this function returns NULL which is later dereferenced by i2c_smbus_read_byte() (called from max732x_readb()). Signed-off-by: Krzysztof Kozlowski Signed-off-by: Linus Walleij --- drivers/gpio/gpio-max732x.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c index 74432da..7c36f2b 100644 --- a/drivers/gpio/gpio-max732x.c +++ b/drivers/gpio/gpio-max732x.c @@ -622,6 +622,13 @@ static int max732x_probe(struct i2c_client *client, goto out_failed; } + if (nr_port > 8 && !chip->client_dummy) { + dev_err(&client->dev, + "Failed to allocate second group I2C device\n"); + ret = -ENODEV; + goto out_failed; + } + mutex_init(&chip->lock); max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]); -- cgit v1.1