From 30bfce0b63fa68c14ae1613eb9d259fa18644074 Mon Sep 17 00:00:00 2001
From: Xinming Hu <huxm@marvell.com>
Date: Fri, 18 May 2018 15:38:54 +0800
Subject: [PATCH] mwifiex: correct histogram data with appropriate index
Git-commit: 30bfce0b63fa68c14ae1613eb9d259fa18644074
Patch-mainline: v4.18-rc1
References: bsc#1051510

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

Signed-off-by: Xinming Hu <huxm@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/wireless/marvell/mwifiex/util.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/util.c b/drivers/net/wireless/marvell/mwifiex/util.c
index 0cd68ffc2c74..51ccf10f4413 100644
--- 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 mwifiex_private *priv, u8 rx_rate, s8 snr,
 			   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 */
-- 
2.18.0