From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E738F17E; Wed, 9 Nov 2022 00:28:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 792B9C433D6; Wed, 9 Nov 2022 00:28:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667953698; bh=HWHf8Rl0nBj9nc3udlptxTqUuonteTAfMEYPiSz8dG4=; h=From:To:Cc:Subject:Date:From; b=q8bHSIZ1IMWsPyMHLigT5XjNnubx5J5ByjfwIQ5gSqiABwFvXHEttHj6trfOiskpm ui6O2j06eX9wveGxOPWfzZ0EBY46uPdhEcPm6FKA0gw6jg2nrHBsBW4OeP9bGjB1DE 6mNDQRLI4oUheiSTHQBqwc9DcjrSb2Wc5crexZEqBJgacf56pvvKOJ9sKqaS3ilP98 LkwpUKpRxGq2JdccJ6uC6gDt221EVzEa0M35ZUmjvqVzuVjkBXG65cqsOON7qO2DQm polFPC/b5YciteDnmsWIuPYaZ0Buc4w9PP34R6jP26F6ny/NpdElarpxP1t4CVWjiF NMvYdsInyuJ4g== From: Nathan Chancellor To: "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Dexuan Cui , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: linux-hyperv@vger.kernel.org, netdev@vger.kernel.org, Nick Desaulniers , Tom Rix , Kees Cook , Sami Tolvanen , llvm@lists.linux.dev, linux-kernel@vger.kernel.org, patches@lists.linux.dev, Nathan Huckleberry , Dan Carpenter , Nathan Chancellor Subject: [PATCH v3] net: mana: Fix return type of mana_start_xmit() Date: Tue, 8 Nov 2022 17:26:30 -0700 Message-Id: <20221109002629.1446680-1-nathan@kernel.org> X-Mailer: git-send-email 2.38.1 Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Nathan Huckleberry The ndo_start_xmit field in net_device_ops is expected to be of type netdev_tx_t (*ndo_start_xmit)(struct sk_buff *skb, struct net_device *dev). The mismatched return type breaks forward edge kCFI since the underlying function definition does not match the function hook definition. A new warning in clang will catch this at compile time: drivers/net/ethernet/microsoft/mana/mana_en.c:382:21: 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 = mana_start_xmit, ^~~~~~~~~~~~~~~ 1 error generated. The return type of mana_start_xmit should be changed from int to netdev_tx_t. Reported-by: Dan Carpenter Link: https://github.com/ClangBuiltLinux/linux/issues/1703 Link: https://github.com/ClangBuiltLinux/linux/issues/1750 Signed-off-by: Nathan Huckleberry Reviewed-by: Dexuan Cui [nathan: Rebase on net-next and resolve conflicts Add note about new clang warning] Signed-off-by: Nathan Chancellor --- v3: - Take over for Nathan, as he is busy with other matters. - Rebase on net-next and resolve conflicts. - Add a note about new clang warning that will catch this issue at compile time. v2: https://lore.kernel.org/20220929181411.61331-1-nhuck@google.com/ drivers/net/ethernet/microsoft/mana/mana.h | 2 +- drivers/net/ethernet/microsoft/mana/mana_en.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/microsoft/mana/mana.h b/drivers/net/ethernet/microsoft/mana/mana.h index d58be64374c8..ffcd27cde17b 100644 --- a/drivers/net/ethernet/microsoft/mana/mana.h +++ b/drivers/net/ethernet/microsoft/mana/mana.h @@ -388,7 +388,7 @@ struct mana_port_context { struct mana_ethtool_stats eth_stats; }; -int mana_start_xmit(struct sk_buff *skb, struct net_device *ndev); +netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev); int mana_config_rss(struct mana_port_context *ac, enum TRI_STATE rx, bool update_hash, bool update_tab); diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index 318dbbb48279..91a8d3577c14 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -128,7 +128,7 @@ static int mana_map_skb(struct sk_buff *skb, struct mana_port_context *apc, return -ENOMEM; } -int mana_start_xmit(struct sk_buff *skb, struct net_device *ndev) +netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev) { enum mana_tx_pkt_format pkt_fmt = MANA_SHORT_PKT_FMT; struct mana_port_context *apc = netdev_priv(ndev); base-commit: 8e18be7610aebea50e9327c11afcd5eeaaa06644 -- 2.38.1