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 88232C433DF for ; Tue, 9 Jun 2020 00:34:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DFE1207ED for ; Tue, 9 Jun 2020 00:34:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591662848; bh=rrjn21lIwbVsYMAky8QjM0Drt8vWHEafCQYkuckifaw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=w58wzVQza+5HpGbG9DG8ox+3k3mpczgHLHAxmmBlyCP0LGvU0h8hVxYgQPO2NqE6y Sv9YnpepTMa331+AH1NaOFkmJ9jx3oStkXPB+rpMUQhO+q/kL2pOGWjba8Nd2UVjeN ob3PZAIUpVFgEswrDJ5FI4N2RsZAftGBarYDMxzg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733183AbgFIAeH (ORCPT ); Mon, 8 Jun 2020 20:34:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:35110 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729860AbgFHXOk (ORCPT ); Mon, 8 Jun 2020 19:14:40 -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 240F220B80; Mon, 8 Jun 2020 23:14:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591658080; bh=rrjn21lIwbVsYMAky8QjM0Drt8vWHEafCQYkuckifaw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zb7FJYs55fFUxCLo+hv1nZucmhoVxk8NW8oChDs23eKIKvetgoKaNsbbHjZOUNcSA LN4yunzAQjmko5/beefzUZJpYwuVcmnG+JTpY+qCIZVkt6OOXnM934DbhYM+zc7yS9 wJSroqLDXNWWs5nFPCLPnppCUhHd30Ym0DVgzTPw= 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 5.6 124/606] stmmac: fix pointer check after utilization in stmmac_interrupt Date: Mon, 8 Jun 2020 19:04:09 -0400 Message-Id: <20200608231211.3363633-124-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608231211.3363633-1-sashal@kernel.org> References: <20200608231211.3363633-1-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 7da18c9afa01..d564459290ce 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; -- 2.25.1