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 <k.kozlowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index 74432daa..7c36f2b 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -622,6 +622,13 @@
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]);