If per_time_scales[i] or per_time_gains[i] kcalloc fails in the for loop
of iio_gts_build_avail_scale_table(), the err_free_out will fail to call
kfree() each time when i is reduced to 0, so all the per_time_scales[0]
and per_time_gains[0] will not be freed, which will cause memory leaks.

Fix it by checking if i >= 0.

Cc: stable@vger.kernel.org
Fixes: 38416c28e168 ("iio: light: Add gain-time-scale helpers")
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
---
v2:
- Update the commit message.
- Add Reviewed-by.
---
 drivers/iio/industrialio-gts-helper.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/industrialio-gts-helper.c b/drivers/iio/industrialio-gts-helper.c
index 7326c7949244..5f131bc1a01e 100644
--- a/drivers/iio/industrialio-gts-helper.c
+++ b/drivers/iio/industrialio-gts-helper.c
@@ -315,7 +315,7 @@ static int iio_gts_build_avail_scale_table(struct iio_gts *gts)
 	return 0;
 
 err_free_out:
-	for (i--; i; i--) {
+	for (i--; i >= 0; i--) {
 		kfree(per_time_scales[i]);
 		kfree(per_time_gains[i]);
 	}
-- 
2.34.1

On Wed, 16 Oct 2024 09:24:53 +0800
Jinjie Ruan <ruanjinjie@huawei.com> wrote:

> If per_time_scales[i] or per_time_gains[i] kcalloc fails in the for loop
> of iio_gts_build_avail_scale_table(), the err_free_out will fail to call
> kfree() each time when i is reduced to 0, so all the per_time_scales[0]
> and per_time_gains[0] will not be freed, which will cause memory leaks.
> 
> Fix it by checking if i >= 0.
> 
> Cc: stable@vger.kernel.org
> Fixes: 38416c28e168 ("iio: light: Add gain-time-scale helpers")
> Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Applied.
> ---
> v2:
> - Update the commit message.
> - Add Reviewed-by.
> ---
>  drivers/iio/industrialio-gts-helper.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/industrialio-gts-helper.c b/drivers/iio/industrialio-gts-helper.c
> index 7326c7949244..5f131bc1a01e 100644
> --- a/drivers/iio/industrialio-gts-helper.c
> +++ b/drivers/iio/industrialio-gts-helper.c
> @@ -315,7 +315,7 @@ static int iio_gts_build_avail_scale_table(struct iio_gts *gts)
>  	return 0;
>  
>  err_free_out:
> -	for (i--; i; i--) {
> +	for (i--; i >= 0; i--) {
>  		kfree(per_time_scales[i]);
>  		kfree(per_time_gains[i]);
>  	}