[PATCH 4.17 141/336] mwifiex: correct histogram data with appropriate index

From: Greg Kroah-Hartman
Date: Wed Aug 01 2018 - 14:25:43 EST


4.17-stable review patch. If anyone has any objections, please let me know.

------------------

From: Xinming Hu <huxm@xxxxxxxxxxx>

[ Upstream commit 30bfce0b63fa68c14ae1613eb9d259fa18644074 ]

Correct snr/nr/rssi data index to avoid possible buffer underflow.

Signed-off-by: Xinming Hu <huxm@xxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/wireless/marvell/mwifiex/util.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

--- a/drivers/net/wireless/marvell/mwifiex/util.c
+++ b/drivers/net/wireless/marvell/mwifiex/util.c
@@ -708,12 +708,14 @@ void mwifiex_hist_data_set(struct mwifie
s8 nflr)
{
struct mwifiex_histogram_data *phist_data = priv->hist_data;
+ s8 nf = -nflr;
+ s8 rssi = snr - nflr;

atomic_inc(&phist_data->num_samples);
atomic_inc(&phist_data->rx_rate[rx_rate]);
- atomic_inc(&phist_data->snr[snr]);
- atomic_inc(&phist_data->noise_flr[128 + nflr]);
- atomic_inc(&phist_data->sig_str[nflr - snr]);
+ atomic_inc(&phist_data->snr[snr + 128]);
+ atomic_inc(&phist_data->noise_flr[nf + 128]);
+ atomic_inc(&phist_data->sig_str[rssi + 128]);
}

/* function to reset histogram data during init/reset */