From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kalle Valo Subject: Re: rsi: fix integer overflow warning Date: Fri, 13 Oct 2017 10:00:59 +0000 (UTC) Message-ID: <20171013100100.B7A2F605A5@smtp.codeaurora.org> References: <20171005120547.328687-1-arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Prameela Rani Garnepudi , Amitkumar Karwar , Arnd Bergmann , Pavani Muthyala , Karun Eagalapati , linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann Return-path: In-Reply-To: <20171005120547.328687-1-arnd-r2nGTMty4D4@public.gmane.org> Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org Arnd Bergmann wrote: > gcc produces a harmless warning about a recently introduced > signed integer overflow: > > drivers/net/wireless/rsi/rsi_91x_hal.c: In function 'rsi_prepare_mgmt_desc': > include/uapi/linux/swab.h:13:15: error: integer overflow in expression [-Werror=overflow] > (((__u16)(x) & (__u16)0x00ffU) << 8) | \ > ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~ > include/uapi/linux/swab.h:104:2: note: in expansion of macro '___constant_swab16' > ___constant_swab16(x) : \ > ^~~~~~~~~~~~~~~~~~ > include/uapi/linux/byteorder/big_endian.h:34:43: note: in expansion of macro '__swab16' > #define __cpu_to_le16(x) ((__force __le16)__swab16((x))) > ^~~~~~~~ > include/linux/byteorder/generic.h:89:21: note: in expansion of macro '__cpu_to_le16' > #define cpu_to_le16 __cpu_to_le16 > ^~~~~~~~~~~~~ > drivers/net/wireless/rsi/rsi_91x_hal.c:136:3: note: in expansion of macro 'cpu_to_le16' > cpu_to_le16((tx_params->vap_id << RSI_DESC_VAP_ID_OFST) & > ^~~~~~~~~~~ > > The problem is that the 'mask' value is a signed integer that gets > turned into a negative number when truncated to 16 bits. Making it > an unsigned constant avoids this. > > Fixes: eac4eed3224b ("rsi: tx and rx path enhancements for p2p mode") > Signed-off-by: Arnd Bergmann Patch applied to wireless-drivers-next.git, thanks. a39644b235c1 rsi: fix integer overflow warning -- https://patchwork.kernel.org/patch/9986961/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches