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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 600ADC433E1 for ; Wed, 24 Mar 2021 15:22:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26B6C619A4 for ; Wed, 24 Mar 2021 15:22:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236634AbhCXPVw (ORCPT ); Wed, 24 Mar 2021 11:21:52 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:46398 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236497AbhCXPVl (ORCPT ); Wed, 24 Mar 2021 11:21:41 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1lP5KB-0002zn-T7; Wed, 24 Mar 2021 15:21:35 +0000 From: Colin King To: Larry Finger , Greg Kroah-Hartman , Martin Kaiser , linux-staging@lists.linux.dev Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH][next] staging: rtl8188eu: Fix null pointer dereference on free_netdev call Date: Wed, 24 Mar 2021 15:21:35 +0000 Message-Id: <20210324152135.254152-1-colin.king@canonical.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Colin Ian King An unregister_netdev call checks if pnetdev is null, hence a later call to free_netdev can potentially be passing a null pointer, causing a null pointer dereference. Avoid this by adding a null pointer check on pnetdev before calling free_netdev. Fixes: 1665c8fdffbb ("staging: rtl8188eu: use netdev routines for private data") Signed-off-by: Colin Ian King --- drivers/staging/rtl8188eu/os_dep/usb_intf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/rtl8188eu/os_dep/usb_intf.c b/drivers/staging/rtl8188eu/os_dep/usb_intf.c index 518e9feb3f46..91a3d34a1050 100644 --- a/drivers/staging/rtl8188eu/os_dep/usb_intf.c +++ b/drivers/staging/rtl8188eu/os_dep/usb_intf.c @@ -446,7 +446,8 @@ static void rtw_usb_if1_deinit(struct adapter *if1) pr_debug("+r871xu_dev_remove, hw_init_completed=%d\n", if1->hw_init_completed); rtw_free_drv_sw(if1); - free_netdev(pnetdev); + if (pnetdev) + free_netdev(pnetdev); } static int rtw_drv_init(struct usb_interface *pusb_intf, const struct usb_device_id *pdid) -- 2.30.2