2021-02-16 15:18:34

by Colin King

[permalink] [raw]
Subject: [PATCH][next] thermal: qcom: Fix comparison with uninitialized variable channels_available

From: Colin Ian King <[email protected]>

Currently the check of chip->channels[i].channel is against an the
uninitialized variable channels_available. I believe the variable
channels_available needs to be fetched first by the call to adc_tm5_read
before the channels check. Fix the issue swapping the order of the
channels check loop with the call to adc_tm5_read.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: ca66dca5eda6 ("thermal: qcom: add support for adc-tm5 PMIC thermal monitor")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/thermal/qcom/qcom-spmi-adc-tm5.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/thermal/qcom/qcom-spmi-adc-tm5.c b/drivers/thermal/qcom/qcom-spmi-adc-tm5.c
index a2014375587d..b460b56e981c 100644
--- a/drivers/thermal/qcom/qcom-spmi-adc-tm5.c
+++ b/drivers/thermal/qcom/qcom-spmi-adc-tm5.c
@@ -375,13 +375,6 @@ static int adc_tm5_init(struct adc_tm5_chip *chip)
int ret;
unsigned int i;

- for (i = 0; i < chip->nchannels; i++) {
- if (chip->channels[i].channel >= channels_available) {
- dev_err(chip->dev, "Invalid channel %d\n", chip->channels[i].channel);
- return -EINVAL;
- }
- }
-
ret = adc_tm5_read(chip, ADC_TM5_NUM_BTM,
&channels_available, sizeof(channels_available));
if (ret) {
@@ -389,6 +382,13 @@ static int adc_tm5_init(struct adc_tm5_chip *chip)
return ret;
}

+ for (i = 0; i < chip->nchannels; i++) {
+ if (chip->channels[i].channel >= channels_available) {
+ dev_err(chip->dev, "Invalid channel %d\n", chip->channels[i].channel);
+ return -EINVAL;
+ }
+ }
+
buf[0] = chip->decimation;
buf[1] = chip->avg_samples | ADC_TM5_FAST_AVG_EN;
buf[2] = ADC_TM5_TIMER1;
--
2.30.0