Received-SPF: pass (google.com: best guess record for domain of linux-wireless-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 3 May 2019 13:53:33 +0200
From:   Stanislaw Gruszka <sgruszka@redhat.com>
To:     Tony Chuang <yhchuang@realtek.com>
Cc:     linux-wireless@vger.kernel.org
Subject: [RFC] rtw88: fix subscript above array bounds compiler warning
Message-ID: <20190503115333.GA23109@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-wireless-owner@vger.kernel.org
Precedence: bulk

My compiler complain about:

drivers/net/wireless/realtek/rtw88/phy.c: In function ‘rtw_phy_rf_power_2_rssi’:
drivers/net/wireless/realtek/rtw88/phy.c:430:26: warning: array subscript is above array bounds [-Warray-bounds]
  linear = db_invert_table[i][j];

According to comment power_db should be in range 1 ~ 96 .
Correct rtw_phy_power_2_db() to make max power 96 db
(still min is 0). This make the warning gone.

However power >= 20 check still looks somewhat suspicious to me.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
---
 drivers/net/wireless/realtek/rtw88/phy.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/phy.c b/drivers/net/wireless/realtek/rtw88/phy.c
index 35a35dbca85f..a716a44d78b0 100644
--- a/drivers/net/wireless/realtek/rtw88/phy.c
+++ b/drivers/net/wireless/realtek/rtw88/phy.c
@@ -410,12 +410,12 @@ void rtw_phy_dynamic_mechanism(struct rtw_dev *rtwdev)
 
 static u8 rtw_phy_power_2_db(s8 power)
 {
-	if (power <= -100 || power >= 20)
+	if (power <= -96 || power >= 20)
 		return 0;
 	else if (power >= 0)
-		return 100;
+		return 96;
 	else
-		return 100 + power;
+		return 96 + power;
 }
 
 static u64 rtw_phy_db_2_linear(u8 power_db)
-- 
1.9.3