mfd: max8925: Fix possible NULL pointer dereference on i2c_new_dummy error
During probe the driver allocates dummy I2C devices for RTC and ADC
with i2c_new_dummy() but it does not check the return value of this
calls.
In case of error (i2c_new_device(): memory allocation failure or I2C
address cannot be used) this function returns NULL which is later used
by i2c_unregister_device().
If i2c_new_dummy() fails for RTC or ADC devices, fail also the probe
for main MFD driver.
Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/max8925-i2c.c b/drivers/mfd/max8925-i2c.c
index 176aa26..a83eed5 100644
--- a/drivers/mfd/max8925-i2c.c
+++ b/drivers/mfd/max8925-i2c.c
@@ -181,9 +181,18 @@
mutex_init(&chip->io_lock);
chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR);
+ if (!chip->rtc) {
+ dev_err(chip->dev, "Failed to allocate I2C device for RTC\n");
+ return -ENODEV;
+ }
i2c_set_clientdata(chip->rtc, chip);
chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR);
+ if (!chip->adc) {
+ dev_err(chip->dev, "Failed to allocate I2C device for ADC\n");
+ i2c_unregister_device(chip->rtc);
+ return -ENODEV;
+ }
i2c_set_clientdata(chip->adc, chip);
device_init_wakeup(&client->dev, 1);