[PATCH] regulator: fan53555: Check pdata->slew_rate setting

From: Axel Lin
Date: Sat Feb 23 2019 - 23:10:10 EST


Current code does not really avoid array access out of bounds,
fix it by add checking for pdata->slew_rate.
If pdata->slew_rate is too big, it's a bug in pdata that needs fix.

Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
---
drivers/regulator/fan53555.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/fan53555.c b/drivers/regulator/fan53555.c
index d7142352f6bc..771a06d1900d 100644
--- a/drivers/regulator/fan53555.c
+++ b/drivers/regulator/fan53555.c
@@ -490,11 +490,13 @@ static int fan53555_regulator_probe(struct i2c_client *client,
} else {
/* if no ramp constraint set, get the pdata ramp_delay */
if (!di->regulator->constraints.ramp_delay) {
- int slew_idx = (pdata->slew_rate & 0x7)
- ? pdata->slew_rate : 0;
+ if (pdata->slew_rate >= ARRAY_SIZE(slew_rates)) {
+ dev_err(&client->dev, "Invalid slew_rate\n");
+ return -EINVAL;
+ }

di->regulator->constraints.ramp_delay
- = slew_rates[slew_idx];
+ = slew_rates[pdata->slew_rate];
}

di->vendor = id->driver_data;
--
2.17.1