From: "zhili.liu" <zhili.liu@xxxxxxxxxxx>
Recently, we encounter kernel crash in function rm3100_common_probe
caused by out of bound access of array rm3100_samp_rates (because of
underlying hardware failures). Add boundary check to prevent out of
bound access.
Fixes: 121354b2eceb ("iio: magnetometer: Add driver support for PNI RM3100")
Suggested-by: Zhouyi Zhou <zhouzhouyi@xxxxxxxxx>
Signed-off-by: zhili.liu <zhili.liu@xxxxxxxxxxx>
---
drivers/iio/magnetometer/rm3100-core.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/iio/magnetometer/rm3100-core.c b/drivers/iio/magnetometer/rm3100-core.c
index 69938204456f..12c2e3b0aeb6 100644
--- a/drivers/iio/magnetometer/rm3100-core.c
+++ b/drivers/iio/magnetometer/rm3100-core.c
@@ -530,6 +530,7 @@ int rm3100_common_probe(struct device *dev, struct regmap *regmap, int irq)
struct rm3100_data *data;
unsigned int tmp;
int ret;
+ int samp_rate_index;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
@@ -586,8 +587,14 @@ int rm3100_common_probe(struct device *dev, struct regmap *regmap, int irq)
ret = regmap_read(regmap, RM3100_REG_TMRC, &tmp);
if (ret < 0)
return ret;
+
+ samp_rate_index = tmp - RM3100_TMRC_OFFSET;
+ if (samp_rate_index < 0 || samp_rate_index >= RM3100_SAMP_NUM) {
+ dev_err(dev, "The value read from RM3100_REG_TMRC is invalid!\n");
+ return -EINVAL;
+ }
/* Initializing max wait time, which is double conversion time. */
- data->conversion_time = rm3100_samp_rates[tmp - RM3100_TMRC_OFFSET][2]
+ data->conversion_time = rm3100_samp_rates[samp_rate_index][2]
* 2;
/* Cycle count values may not be what we want. */
--
2.34.1
