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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF2C5C10F1E for ; Sun, 18 Dec 2022 17:01:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233169AbiLRRA6 (ORCPT ); Sun, 18 Dec 2022 12:00:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38280 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233166AbiLRQ7u (ORCPT ); Sun, 18 Dec 2022 11:59:50 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 03D9F1D306; Sun, 18 Dec 2022 08:20:35 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 8E0F7B80B43; Sun, 18 Dec 2022 16:20:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC718C433EF; Sun, 18 Dec 2022 16:20:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1671380433; bh=FpBev2TRlBot6nW8kIO6yuMp+zZp19D+9AzteDvmyig=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nDWZAdTdp42D/Df8koVT42kNXPnyVAKM2jQr38cr3ua/aj1AdBChwswOAv15JNrw0 pBbEHwa6eNpigN6wGINQWHIr2NVvXXuKzrb63AUaVu+GNzHsXmbfJRbYPQRXop7DEB k87mYVW9fa0+u9CZ4kvoiNx7TKpHxZ2zOE90HMOyNkDgkchA8Zkhc55650PlXHN8uK DIpFFvYpM77g+2KZcIqzKTtktbsPXzxH7lhSbiwGLDKWCJFQohbDedlTvz1c2StWqO 7+f/iJX7rGRxEnfoV8pLFTsIvnR1sFQv7GttFMuWMV72pd1WhzGFwoQzyutYlREx+/ VxDSY6RT7FoOw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nathan Chancellor , Kees Cook , Jakub Kicinski , Sasha Levin , davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, ndesaulniers@google.com, mkl@pengutronix.de, wintera@linux.ibm.com, mathew.j.martineau@linux.intel.com, elder@linaro.org, colin.i.king@gmail.com, netdev@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH AUTOSEL 4.19 06/26] net: ethernet: ti: Fix return type of netcp_ndo_start_xmit() Date: Sun, 18 Dec 2022 11:19:56 -0500 Message-Id: <20221218162016.934280-6-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221218162016.934280-1-sashal@kernel.org> References: <20221218162016.934280-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Nathan Chancellor [ Upstream commit 63fe6ff674a96cfcfc0fa8df1051a27aa31c70b4 ] 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 proposed warning in clang aims to catch these at compile time, which reveals: drivers/net/ethernet/ti/netcp_core.c:1944:21: 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] .ndo_start_xmit = netcp_ndo_start_xmit, ^~~~~~~~~~~~~~~~~~~~ 1 error generated. ->ndo_start_xmit() in 'struct net_device_ops' expects a return type of 'netdev_tx_t', not 'int'. Adjust the return type of netcp_ndo_start_xmit() to match the prototype's to resolve the warning and CFI failure. Link: https://github.com/ClangBuiltLinux/linux/issues/1750 Signed-off-by: Nathan Chancellor Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20221102160933.1601260-1-nathan@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/ti/netcp_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ti/netcp_core.c b/drivers/net/ethernet/ti/netcp_core.c index 6099865217f2..7fdbd2ff5573 100644 --- a/drivers/net/ethernet/ti/netcp_core.c +++ b/drivers/net/ethernet/ti/netcp_core.c @@ -1276,7 +1276,7 @@ static int netcp_tx_submit_skb(struct netcp_intf *netcp, } /* Submit the packet */ -static int netcp_ndo_start_xmit(struct sk_buff *skb, struct net_device *ndev) +static netdev_tx_t netcp_ndo_start_xmit(struct sk_buff *skb, struct net_device *ndev) { struct netcp_intf *netcp = netdev_priv(ndev); struct netcp_stats *tx_stats = &netcp->stats; -- 2.35.1