From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BC617ECE57B for ; Mon, 9 Sep 2024 08:54:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Bnk2hM3gPyCwS6xT8wGOoaIo0zZ5l4gVWe1MokTvqIM=; b=k5C+B/lqpW2lRIoke5HZeokDNh hv5I7YAKTjkDEtzAtTroQ7g1KdPj9J/iXo37kbhQmLcNLmTE6loIUuUcQYxGu3ZDOQYbmBeIlx6wT UInZK33Jc9TDwc1NDci79gYTjd4w2cNiD0atcn/4Eaeim8XphM6RzfXCOkK0ThaDxoM8N1cUth2KR I8WcDQ3V3EMxwsKrbPzW0CIDIRjlHtY/p59B+Caucxb1+e/LSVrE4eHGRF94W62lFYJyRpa8ioTqB cJAzWIhI/Vjf6oV0s3wIUV2aV7qETjjMDrRw/7JHcd1D2kJoi3N4b8TNWQPhACDb57iz+8cGA7TOH RmZhYzIw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sna9o-00000001C1h-3Ua1; Mon, 09 Sep 2024 08:54:00 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sna11-00000001AIA-2D9p; Mon, 09 Sep 2024 08:44:56 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id DF21EA428C2; Mon, 9 Sep 2024 08:44:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27DBDC4CEC5; Mon, 9 Sep 2024 08:44:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725871494; bh=pxwM3hSVCglKIf6EY3IGEl3ujf1W94/lMRDKTRO7k1Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=caX8MYpZb9kl5CtRpFChwjoo+mPfLkxCM4HtGqCmEm0QDaIhRoPIprkfXTtm+JAas LmNd9As91CDNi38gy9YLO++ILkd4S0cr7q1S424GVVGq4BoptWsrldGI3pGz+et2V8 qo6Z2VLIUCbTW+fQcZWYx6Bu3vOXTXEdr0yUm33/HMZaallcrdBwEE5B/hyJedujsl vMXHkUd36/2BzPM2fi33MeyJ8MoHEXK4h5TjjhcOfKHjFSmw8K4xNPWLZnjf8nlVqi iHXTe9OQbM5STDecrBzkNQA2XIMM21gDE0b27c27+p4LPDr02+RpIyS3UbkTEVE+j+ JFT7sSQOXZ2Sg== Date: Mon, 9 Sep 2024 09:44:48 +0100 From: Simon Horman To: Nathan Chancellor Cc: Marc Kleine-Budde , kernel@pengutronix.de, Vincent Mailhol , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Heiko Stuebner , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, llvm@lists.linux.dev, patches@lists.linux.dev Subject: Re: [PATCH] can: rockchip_canfd: fix return type of rkcanfd_start_xmit() Message-ID: <20240909084448.GU2097826@kernel.org> References: <20240906-rockchip-canfd-wifpts-v1-1-b1398da865b7@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240906-rockchip-canfd-wifpts-v1-1-b1398da865b7@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240909_014455_654784_79BDEBE3 X-CRM114-Status: GOOD ( 14.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Sep 06, 2024 at 01:26:41PM -0700, Nathan Chancellor wrote: > With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), > indirect call targets are validated against the expected function > pointer prototype to make sure the call target is valid to help mitigate > ROP attacks. If they are not identical, there is a failure at run time, > which manifests as either a kernel panic or thread getting killed. A > warning in clang aims to catch these at compile time, which reveals: > > drivers/net/can/rockchip/rockchip_canfd-core.c:770:20: error: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Werror,-Wincompatible-function-pointer-types-strict] > 770 | .ndo_start_xmit = rkcanfd_start_xmit, > | ^~~~~~~~~~~~~~~~~~ > > ->ndo_start_xmit() in 'struct net_device_ops' expects a return type of > 'netdev_tx_t', not 'int' (although the types are ABI compatible). Adjust > the return type of rkcanfd_start_xmit() to match the prototype's to > resolve the warning. > > Fixes: ff60bfbaf67f ("can: rockchip_canfd: add driver for Rockchip CAN-FD controller") > Signed-off-by: Nathan Chancellor Thanks, I was able to reproduce this problem at build time and that your patch addresses it. Reviewed-by: Simon Horman