From: Arnd Bergmann <arnd@xxxxxxxx>
After -Wstringop-overflow got enabled, the rtw89 driver produced
two odd warnings with gcc-13:
drivers/net/wireless/realtek/rtw89/coex.c: In function 'rtw89_btc_ntfy_scan_start':
drivers/net/wireless/realtek/rtw89/coex.c:5362:50: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
5362 | wl->dbcc_info.scan_band[phy_idx] = band;
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
In file included from drivers/net/wireless/realtek/rtw89/coex.h:8,
from drivers/net/wireless/realtek/rtw89/coex.c:5:
drivers/net/wireless/realtek/rtw89/core.h:1441:12: note: at offset [64, 255] into destination object 'scan_band' of size 2
1441 | u8 scan_band[RTW89_PHY_MAX]; /* scan band in each phy */
| ^~~~~~~~~
drivers/net/wireless/realtek/rtw89/coex.c: In function 'rtw89_btc_ntfy_switch_band':
drivers/net/wireless/realtek/rtw89/coex.c:5406:50: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
5406 | wl->dbcc_info.scan_band[phy_idx] = band;
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
drivers/net/wireless/realtek/rtw89/core.h:1441:12: note: at offset [64, 255] into destination object 'scan_band' of size 2
1441 | u8 scan_band[RTW89_PHY_MAX]; /* scan band in each phy */
| ^~~~~~~~~
I don't know what happened here, but adding an explicit range check
shuts up the output.
Fixes: 89741e7e42f6 ("Makefile: Enable -Wstringop-overflow globally")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/net/wireless/realtek/rtw89/coex.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/net/wireless/realtek/rtw89/coex.c b/drivers/net/wireless/realtek/rtw89/coex.c
index b842cd9a86f8..9c0db35d3e13 100644
--- a/drivers/net/wireless/realtek/rtw89/coex.c
+++ b/drivers/net/wireless/realtek/rtw89/coex.c
@@ -5352,6 +5352,10 @@ void rtw89_btc_ntfy_scan_start(struct rtw89_dev *rtwdev, u8 phy_idx, u8 band)
rtw89_debug(rtwdev, RTW89_DBG_BTC,
"[BTC], %s(): phy_idx=%d, band=%d\n",
__func__, phy_idx, band);
+
+ if (phy_idx >= RTW89_PHY_MAX)
+ return;
+
btc->dm.cnt_notify[BTC_NCNT_SCAN_START]++;
wl->status.map.scan = true;
wl->scan_info.band[phy_idx] = band;
@@ -5396,6 +5400,10 @@ void rtw89_btc_ntfy_switch_band(struct rtw89_dev *rtwdev, u8 phy_idx, u8 band)
rtw89_debug(rtwdev, RTW89_DBG_BTC,
"[BTC], %s(): phy_idx=%d, band=%d\n",
__func__, phy_idx, band);
+
+ if (phy_idx >= RTW89_PHY_MAX)
+ return;
+
btc->dm.cnt_notify[BTC_NCNT_SWITCH_BAND]++;
wl->scan_info.band[phy_idx] = band;
--
2.39.2
