6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zicheng Qu <quzicheng@xxxxxxxxxx>
commit 7452f8a0814bb73f739ee0dab60f099f3361b151 upstream.
In iio_gts_build_avail_time_table(), it is checked that gts->num_itime is
non-zero, but gts->num_itime is not checked in gain_to_scaletables(). The
variable time_idx is initialized as gts->num_itime - 1. This implies that
time_idx might initially be set to -1 (0 - 1 = -1). Consequently, using
while (time_idx--) could lead to an infinite loop.
Cc: stable@xxxxxxxxxxxxxxx # v6.6+
Fixes: 38416c28e168 ("iio: light: Add gain-time-scale helpers")
Signed-off-by: Zicheng Qu <quzicheng@xxxxxxxxxx>
Reviewed-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
Link: https://patch.msgid.link/20241031014626.2313077-1-quzicheng@xxxxxxxxxx
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iio/industrialio-gts-helper.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/iio/industrialio-gts-helper.c
+++ b/drivers/iio/industrialio-gts-helper.c
@@ -205,7 +205,7 @@ static int gain_to_scaletables(struct ii
memcpy(all_gains, gains[time_idx], gain_bytes);
new_idx = gts->num_hwgain;
- while (time_idx--) {
+ while (time_idx-- > 0) {
for (j = 0; j < gts->num_hwgain; j++) {
int candidate = gains[time_idx][j];
int chk;
