From patchwork Thu Jan 6 09:06:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiasheng Jiang X-Patchwork-Id: 530908 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2441C433EF for ; Thu, 6 Jan 2022 09:06:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237141AbiAFJGz (ORCPT ); Thu, 6 Jan 2022 04:06:55 -0500 Received: from smtp25.cstnet.cn ([159.226.251.25]:39792 "EHLO cstnet.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S236715AbiAFJGz (ORCPT ); Thu, 6 Jan 2022 04:06:55 -0500 Received: from localhost.localdomain (unknown [124.16.138.126]) by APP-05 (Coremail) with SMTP id zQCowAA3GRYYsdZhSWS1BQ--.58555S2; Thu, 06 Jan 2022 17:06:32 +0800 (CST) From: Jiasheng Jiang To: gregkh@linuxfoundation.org, jirislaby@kernel.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Jiasheng Jiang Subject: [PATCH] tty/serial: Check for null pointer after calling devm_ioremap Date: Thu, 6 Jan 2022 17:06:31 +0800 Message-Id: <20220106090631.2714586-1-jiasheng@iscas.ac.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: zQCowAA3GRYYsdZhSWS1BQ--.58555S2 X-Coremail-Antispam: 1UD129KBjvdXoW7JFWruF4UZrWxZw1fKF48WFg_yoWDCrX_C3 Z5ua1kAr18CF10va17JryfuFW0q398Zay8Wr1Igr9aq3s5AFs7XFZrWrnIvw4UW3yqvF1U G39rur47Ar409jkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbckFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_ Cr1l84ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s 0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xII jxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVW8JVWxJwAm72CE4IkC6x0Yz7v_Jr0_Gr 1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkIecxEwVAFwVW8uwCF 04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r 18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vI r41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Jr0_Gr 1lIxAIcVCF04k26cxKx2IYs7xG6rWUJVWrZr1UMIIF0xvEx4A2jsIE14v26r4j6F4UMIIF 0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUOo7ZUUUUU= X-Originating-IP: [124.16.138.126] X-CM-SenderInfo: pmld2xxhqjqxpvfd2hldfou0/ Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org As the possible failure of the allocation, the devm_ioremap() may return NULL pointer. And the 'port->membase' will be directly used in mlb_usio_startup(). Therefore, in order to avoid the dereference of the NULL pointer, it should be better to add the sanity check. Fixes: ba44dc043004 ("serial: Add Milbeaut serial control") Signed-off-by: Jiasheng Jiang --- drivers/tty/serial/milbeaut_usio.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/tty/serial/milbeaut_usio.c b/drivers/tty/serial/milbeaut_usio.c index 8f2cab7f66ad..1ecbf6d0dc79 100644 --- a/drivers/tty/serial/milbeaut_usio.c +++ b/drivers/tty/serial/milbeaut_usio.c @@ -523,6 +523,10 @@ static int mlb_usio_probe(struct platform_device *pdev) } port->membase = devm_ioremap(&pdev->dev, res->start, resource_size(res)); + if (!port->membase) { + ret = -ENOMEM; + goto failed; + } ret = platform_get_irq_byname(pdev, "rx"); mlb_usio_irq[index][RX] = ret;