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 B1AA0611A for ; Sun, 28 May 2023 19:18:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D757C433EF; Sun, 28 May 2023 19:18:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685301491; bh=ENDo6/89J1yGoBlmK71uujreDBJABABZbczYgDdCfyA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0/jiUokcqvTlsLwf+fd23PjjHXvGGBnOpAadYiwaFXgT7xFh0BluMGK/Bg2GQrkIE h4DE0FwET1vCCdjiRbFiWD82WKWeIZN96C3MOIGQYfdXvNvj4f9HAXqD9rVYJ56T3y mpgEdEDBD9kW8y2Q/BPLCaP/duW11QasTIwTkxCg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nathan Chancellor , Horatiu Vultur , Paolo Abeni , Sasha Levin Subject: [PATCH 4.19 023/132] net: pasemi: Fix return type of pasemi_mac_start_tx() Date: Sun, 28 May 2023 20:09:22 +0100 Message-Id: <20230528190834.285720527@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230528190833.565872088@linuxfoundation.org> References: <20230528190833.565872088@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Nathan Chancellor [ Upstream commit c8384d4a51e7cb0e6587f3143f29099f202c5de1 ] 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/ethernet/pasemi/pasemi_mac.c:1665:21: 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 = pasemi_mac_start_tx, ^~~~~~~~~~~~~~~~~~~ 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 pasemi_mac_start_tx() to match the prototype's to resolve the warning. While PowerPC does not currently implement support for kCFI, it could in the future, which means this warning becomes a fatal CFI failure at run time. Link: https://github.com/ClangBuiltLinux/linux/issues/1750 Signed-off-by: Nathan Chancellor Reviewed-by: Horatiu Vultur Link: https://lore.kernel.org/r/20230319-pasemi-incompatible-pointer-types-strict-v1-1-1b9459d8aef0@kernel.org Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/ethernet/pasemi/pasemi_mac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/pasemi/pasemi_mac.c b/drivers/net/ethernet/pasemi/pasemi_mac.c index e2c280913fbbb..8238a70161599 100644 --- a/drivers/net/ethernet/pasemi/pasemi_mac.c +++ b/drivers/net/ethernet/pasemi/pasemi_mac.c @@ -1435,7 +1435,7 @@ static void pasemi_mac_queue_csdesc(const struct sk_buff *skb, write_dma_reg(PAS_DMA_TXCHAN_INCR(txring->chan.chno), 2); } -static int pasemi_mac_start_tx(struct sk_buff *skb, struct net_device *dev) +static netdev_tx_t pasemi_mac_start_tx(struct sk_buff *skb, struct net_device *dev) { struct pasemi_mac * const mac = netdev_priv(dev); struct pasemi_mac_txring * const txring = tx_ring(mac); -- 2.39.2