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 972E5C4332F for ; Sun, 18 Dec 2022 16:25:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230453AbiLRQZg (ORCPT ); Sun, 18 Dec 2022 11:25:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231974AbiLRQYV (ORCPT ); Sun, 18 Dec 2022 11:24:21 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7ED9213E94; Sun, 18 Dec 2022 08:09:43 -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 556B2B80BE6; Sun, 18 Dec 2022 16:09:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0C33C433D2; Sun, 18 Dec 2022 16:08:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1671379741; bh=CwJ34qd6UTI9A6IbPwAliuNehPs83ziqfQ//1dcSAEA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qZVjk8WnwvKhK2HAl9nS5L8Cy3FsrT+ZTzvtEEv/+jTdI6iGZ6WrzohSQDlDKyJ9U lOdD1aofvTN7y4f46fAtueYGe48OLK+xAGkoKrX7QcXR5+0OKY2rPCCnjSUTrYPBof Hua9UdQdjRUjVj7zWreBCt4UXAomfZNwhvAAURVB2ylj5pTHvJORZK+/qBoQJUpMFM X41M+9rzf5suo1+k3U8Mm1u+buorPCe8EbF7ex7fVj2ZgzG0jaD5JuAA0jJewnDw12 x26o911Zsi1FgWEfGBclXAI6zOcIlDcIbLo0LDtZ9r/mGIS1UgAc8GlBakuHdd7Vr9 Wnt78QyJ6PAKw== 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, wintera@linux.ibm.com, colin.i.king@gmail.com, netdev@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH AUTOSEL 6.0 21/73] net: ethernet: ti: Fix return type of netcp_ndo_start_xmit() Date: Sun, 18 Dec 2022 11:06:49 -0500 Message-Id: <20221218160741.927862-21-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221218160741.927862-1-sashal@kernel.org> References: <20221218160741.927862-1-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: linux-kernel@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 b15d44261e76..267252560942 100644 --- a/drivers/net/ethernet/ti/netcp_core.c +++ b/drivers/net/ethernet/ti/netcp_core.c @@ -1261,7 +1261,7 @@ 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