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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, T_DKIMWL_WL_HIGH,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 5DFD3C43219 for ; Sat, 4 May 2019 10:29:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28C37206BB for ; Sat, 4 May 2019 10:29:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556965779; bh=Sem2o+BRdo2MN41/QrjREvOG/W8x17nS6VM0QFnHptg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=pJMh+26LfkGyHu1cYgis7DP7dQ2bGxOHOLlr8+MKtINl/LExypRQVVGNe9l6Re9Bd VaDmAb81CVRQGTbALownT5EN5vwpzLypY03K8AnPpKNYsMMLZxiGvi8pYSfZtl3ChJ LREvAWLoaR3Y9oSbYrOk5WIsKn0EC3+klN6DHnpw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728014AbfEDK3i (ORCPT ); Sat, 4 May 2019 06:29:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:36242 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727788AbfEDK0j (ORCPT ); Sat, 4 May 2019 06:26:39 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 000A020859; Sat, 4 May 2019 10:26:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556965598; bh=Sem2o+BRdo2MN41/QrjREvOG/W8x17nS6VM0QFnHptg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LTqL8DgNn3/zvrbD67ladwdlCG3GdVfrH4RKCrrHchVKc87GsfAMUpk7rtQPCdF0+ MxaXGVlp2UgtunQyMdYnPR6rn6//2HwiFjURvWQgs8bHrwEMqBgSXWtRzkz533/Fd+ 9DoQbr7ClSoH3oKIa9pwACrNdHMJIEREDB4QvKQM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Laura Abbott , Gabriel Ramirez , Johannes Berg , Emmanuel Grumbach , Luca Coelho , Intel Linux Wireless , Kalle Valo Subject: [PATCH 5.0 31/32] iwlwifi: mvm: properly check debugfs dentry before using it Date: Sat, 4 May 2019 12:25:16 +0200 Message-Id: <20190504102453.427675597@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190504102452.523724210@linuxfoundation.org> References: <20190504102452.523724210@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg Kroah-Hartman commit 154d4899e4111ae24e68d6ba955f46856cb046bc upstream. debugfs can now report an error code if something went wrong instead of just NULL. So if the return value is to be used as a "real" dentry, it needs to be checked if it is an error before dereferencing it. This is now happening because of ff9fb72bc077 ("debugfs: return error values, not NULL"). If multiple iwlwifi devices are in the system, this can cause problems when the driver attempts to create the main debugfs directory again. Later on in the code we fail horribly by trying to dereference a pointer that is an error value. Reported-by: Laura Abbott Reported-by: Gabriel Ramirez Cc: Johannes Berg Cc: Emmanuel Grumbach Cc: Luca Coelho Cc: Intel Linux Wireless Cc: Kalle Valo Cc: stable # 5.0 Signed-off-by: Luca Coelho Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c @@ -1482,6 +1482,11 @@ void iwl_mvm_vif_dbgfs_register(struct i return; mvmvif->dbgfs_dir = debugfs_create_dir("iwlmvm", dbgfs_dir); + if (IS_ERR_OR_NULL(mvmvif->dbgfs_dir)) { + IWL_ERR(mvm, "Failed to create debugfs directory under %pd\n", + dbgfs_dir); + return; + } if (!mvmvif->dbgfs_dir) { IWL_ERR(mvm, "Failed to create debugfs directory under %pd\n",