Re: wifi: rtw89: avoid stringop-overflow warning

[Kalle Valo]

Arnd Bergmann <arnd@xxxxxxxxxx> wrote:

> 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.
> 
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Patch applied to wireless-next.git, thanks.

595b1280e2c9 wifi: rtw89: avoid stringop-overflow warning

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20231204073020.1105416-1-arnd@xxxxxxxxxx/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches