iio: gts-helper: Fix memory leaks for the error path of iio_gts_build_avail_scale_table()

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>
Link: https://patch.msgid.link/20241016012453.2013302-1-ruanjinjie@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/industrialio-gts-helper.c b/drivers/iio/industrialio-gts-helper.c
index 7326c7949244df386e29307b982566231468fba2..5f131bc1a01e97100fa58174c379bb921753918a 100644 (file)
--- 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]);
        }