From patchwork Thu Dec 16 09:44:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiasheng Jiang X-Patchwork-Id: 524894 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 E7021C433FE for ; Thu, 16 Dec 2021 09:44:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235500AbhLPJoa (ORCPT ); Thu, 16 Dec 2021 04:44:30 -0500 Received: from smtp23.cstnet.cn ([159.226.251.23]:34984 "EHLO cstnet.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S232987AbhLPJo3 (ORCPT ); Thu, 16 Dec 2021 04:44:29 -0500 Received: from localhost.localdomain (unknown [124.16.138.126]) by APP-03 (Coremail) with SMTP id rQCowADX31tpCrth2UZAAw--.30274S2; Thu, 16 Dec 2021 17:44:10 +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] serial: pch_uart: potential dereference of null pointer Date: Thu, 16 Dec 2021 17:44:08 +0800 Message-Id: <20211216094408.352500-1-jiasheng@iscas.ac.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: rQCowADX31tpCrth2UZAAw--.30274S2 X-Coremail-Antispam: 1UD129KBjvdXoWrKry5XFW8Gr4xJw4ftrWDJwb_yoWfurg_Cw n7XwnxAr1j9FZYyFnrJry5CryavayxZFn5uFnag3s3XFWUXFs7Jryqqr9xJw47Gr4DJrZx JwnrGryayr4DujkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbcAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j 6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY02Avz4vE14v_GFWl 42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJV WUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAK I48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r 4UMIIF0xvE42xK8VAvwI8IcIk0rVWrJr0_WFyUJwCI42IY6I8E87Iv67AKxVWUJVW8JwCI 42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfU0VyxDUUUU X-Originating-IP: [124.16.138.126] X-CM-SenderInfo: pmld2xxhqjqxpvfd2hldfou0/ Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org The return value of dma_alloc_coherent() needs to be checked. To avoid dereference of null pointer in case of the failure of alloc. Fixes: ab4382d27412 ("tty: move drivers/serial/ to drivers/tty/serial/") Signed-off-by: Jiasheng Jiang --- drivers/tty/serial/pch_uart.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index f0351e6f0ef6..2ee1c4d6f177 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -745,6 +745,12 @@ static void pch_request_dma(struct uart_port *port) /* Get Consistent memory for DMA */ priv->rx_buf_virt = dma_alloc_coherent(port->dev, port->fifosize, &priv->rx_buf_dma, GFP_KERNEL); + if (!priv->rx_buf_virt) { + dma_release_channel(priv->chan_tx); + priv->chan_tx = NULL; + return; + } + priv->chan_rx = chan; }