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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 373F7C31E5B for ; Tue, 18 Jun 2019 15:39:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1298F2147A for ; Tue, 18 Jun 2019 15:39:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729442AbfFRPj1 (ORCPT ); Tue, 18 Jun 2019 11:39:27 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:54249 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729189AbfFRPj1 (ORCPT ); Tue, 18 Jun 2019 11:39:27 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1hdGCj-000724-6L; Tue, 18 Jun 2019 15:39:25 +0000 From: Colin King To: Benson Leung , Enric Balletbo i Serra , Nick Crews Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH][next] platform/chrome: wilco_ec: fix null pointer dereference on failed kzalloc Date: Tue, 18 Jun 2019 16:39:24 +0100 Message-Id: <20190618153924.19491-1-colin.king@canonical.com> X-Mailer: git-send-email 2.20.1 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: Colin Ian King If the kzalloc of the entries queue q fails a null pointer dereference occurs when accessing q->capacity and q->lock. Add a kzalloc failure check and handle the null return case in the calling function event_device_add. Addresses-Coverity: ("Dereference null return") Fixes: 75589e37d1dc ("platform/chrome: wilco_ec: Add circular buffer as event queue") Signed-off-by: Colin Ian King --- drivers/platform/chrome/wilco_ec/event.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/platform/chrome/wilco_ec/event.c b/drivers/platform/chrome/wilco_ec/event.c index c975b76e6255..e251a989b152 100644 --- a/drivers/platform/chrome/wilco_ec/event.c +++ b/drivers/platform/chrome/wilco_ec/event.c @@ -112,8 +112,11 @@ module_param(queue_size, int, 0644); static struct ec_event_queue *event_queue_new(int capacity) { size_t entries_size = sizeof(struct ec_event *) * capacity; - struct ec_event_queue *q = kzalloc(sizeof(*q) + entries_size, - GFP_KERNEL); + struct ec_event_queue *q; + + q = kzalloc(sizeof(*q) + entries_size, GFP_KERNEL); + if (!q) + return NULL; q->capacity = capacity; spin_lock_init(&q->lock); @@ -474,6 +477,11 @@ static int event_device_add(struct acpi_device *adev) /* Initialize the device data. */ adev->driver_data = dev_data; dev_data->events = event_queue_new(queue_size); + if (!dev_data->events) { + kfree(dev_data); + error = -ENOMEM; + goto free_minor; + } init_waitqueue_head(&dev_data->wq); dev_data->exist = true; atomic_set(&dev_data->available, 1); -- 2.20.1