Re: [PATCH] thermal/drivers/tsens: fix usage of unititialized value

From: Thara Gopinath
Date: Fri Jun 11 2021 - 07:51:27 EST

On 6/8/21 5:41 AM, Yang Li wrote:
When "tsens_version(priv) > VER_0_1" is false,
"regmap_field_read(priv->rf[VER_MINOR], &ver_minor)" can't execute.
So, ver_minor has no initialization and assignment before it is
used, and we initialize it to 0.

Hi Yang,

Thanks for the patch. I have a few questions though.

1. Where do you see ver_minor being used uninitialized? AFAICT , ver_minor is used like below and will never be referenced if version <= VER_0_1
if (tsens_version(priv) > VER_1_X && ver_minor > 2) {

2. Do you know whether minor versions can be read or not on tsens ips with verions < 0_1?

Warm Regards
Thara (She/Her/Hers)

Clean up smatch warning:
drivers/thermal/qcom/tsens.c:896 init_common() error: uninitialized
symbol 'ver_minor'.

Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
Signed-off-by: Yang Li <yang.lee@xxxxxxxxxxxxxxxxx>
drivers/thermal/qcom/tsens.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
index 4c7ebd1..a36c43d 100644
--- a/drivers/thermal/qcom/tsens.c
+++ b/drivers/thermal/qcom/tsens.c
@@ -743,8 +743,8 @@ int __init init_common(struct tsens_priv *priv)
void __iomem *tm_base, *srot_base;
struct device *dev = priv->dev;
- u32 ver_minor;
struct resource *res;
+ u32 ver_minor = 0;
u32 enabled;
int ret, i, j;
struct platform_device *op = of_find_device_by_node(priv->dev->of_node);