[PATCH 5.16 0510/1039] iio: chemical: sunrise_co2: set val parameter only on success

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 18:57:49 EST


From: Tom Rix <trix@xxxxxxxxxx>

[ Upstream commit 38ac2f038666521f94d4fa37b5a9441cef832ccf ]

Clang static analysis reports this representative warning

sunrise_co2.c:410:9: warning: Assigned value is garbage or undefined
*val = value;
^ ~~~~~

The ealier call to sunrise_read_word can fail without setting
value. So defer setting val until we know the read was successful.

Fixes: c397894e24f1 ("iio: chemical: Add Senseair Sunrise 006-0-007 driver")
Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211224150833.3278236-1-trix@xxxxxxxxxx
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/chemical/sunrise_co2.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/chemical/sunrise_co2.c b/drivers/iio/chemical/sunrise_co2.c
index 233bd0f379c93..8440dc0c77cfe 100644
--- a/drivers/iio/chemical/sunrise_co2.c
+++ b/drivers/iio/chemical/sunrise_co2.c
@@ -407,24 +407,24 @@ static int sunrise_read_raw(struct iio_dev *iio_dev,
mutex_lock(&sunrise->lock);
ret = sunrise_read_word(sunrise, SUNRISE_CO2_FILTERED_COMP_REG,
&value);
- *val = value;
mutex_unlock(&sunrise->lock);

if (ret)
return ret;

+ *val = value;
return IIO_VAL_INT;

case IIO_TEMP:
mutex_lock(&sunrise->lock);
ret = sunrise_read_word(sunrise, SUNRISE_CHIP_TEMPERATURE_REG,
&value);
- *val = value;
mutex_unlock(&sunrise->lock);

if (ret)
return ret;

+ *val = value;
return IIO_VAL_INT;

default:
--
2.34.1