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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E984FC433E2 for ; Thu, 14 May 2020 19:10:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA66720575 for ; Thu, 14 May 2020 19:10:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589483414; bh=veUa5lPzb2f+GGa/q/g1p26zaED/KCLS87AS6qy4gaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=JuxrBOa1JeCKkHa1tSm8OdR2f2BjIAO47RtV25aVWc7IbDkH1I+OYWsbAThjGfomL HWEN/KH5anVjzkixHZVyEmh3vqpW+TWdNBramX9ZBms66RHloTO6oymWtZEH7WhvNV LaJ0s+YPmZ/f391vE3nLZeJfr/YdvJ82RkQ6L7fs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730276AbgENTKN (ORCPT ); Thu, 14 May 2020 15:10:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:50912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728386AbgENSwg (ORCPT ); Thu, 14 May 2020 14:52:36 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9273B20722; Thu, 14 May 2020 18:52:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589482355; bh=veUa5lPzb2f+GGa/q/g1p26zaED/KCLS87AS6qy4gaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QhGiMmiTji4wIUGm4nE5aWGX226zIicha9iLgmYnFgEIZFmffpGqYdCZMPtvox4O8 yXjaLD/y+c9i+nbr8fI0PLN9mDPATWT+HlaFn/tehxlN5p6PjRX97Nq2DAZsaC+deu CwT7Qom53lDvUXYrFeG7ecrwr3d9wO514dwFSKiE= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Maxim Petrov , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 5.6 36/62] stmmac: fix pointer check after utilization in stmmac_interrupt Date: Thu, 14 May 2020 14:51:21 -0400 Message-Id: <20200514185147.19716-36-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200514185147.19716-1-sashal@kernel.org> References: <20200514185147.19716-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Maxim Petrov [ Upstream commit f42234ffd531ca6b13d9da02faa60b72eccf8334 ] The paranoidal pointer check in IRQ handler looks very strange - it really protects us only against bogus drivers which request IRQ line with null pointer dev_id. However, the code fragment is incorrect because the dev pointer is used before the actual check which leads to undefined behavior. Remove the check to avoid confusing people with incorrect code. Signed-off-by: Maxim Petrov Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 7da18c9afa01d..d564459290ce1 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3988,7 +3988,7 @@ static int stmmac_set_features(struct net_device *netdev, /** * stmmac_interrupt - main ISR * @irq: interrupt number. - * @dev_id: to pass the net device pointer. + * @dev_id: to pass the net device pointer (must be valid). * Description: this is the main driver interrupt service routine. * It can call: * o DMA service routine (to manage incoming frame reception and transmission @@ -4012,11 +4012,6 @@ static irqreturn_t stmmac_interrupt(int irq, void *dev_id) if (priv->irq_wake) pm_wakeup_event(priv->device, 0); - if (unlikely(!dev)) { - netdev_err(priv->dev, "%s: invalid dev pointer\n", __func__); - return IRQ_NONE; - } - /* Check if adapter is up */ if (test_bit(STMMAC_DOWN, &priv->state)) return IRQ_HANDLED; -- 2.20.1