From patchwork Fri Mar 6 06:47:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Satya Priya X-Patchwork-Id: 214218 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, 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 DABBCC3F2D5 for ; Fri, 6 Mar 2020 06:47:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB3A82084E for ; Fri, 6 Mar 2020 06:47:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726026AbgCFGrk (ORCPT ); Fri, 6 Mar 2020 01:47:40 -0500 Received: from alexa-out-blr-01.qualcomm.com ([103.229.18.197]:8534 "EHLO alexa-out-blr-01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726025AbgCFGrk (ORCPT ); Fri, 6 Mar 2020 01:47:40 -0500 Received: from ironmsg01-blr.qualcomm.com ([10.86.208.130]) by alexa-out-blr-01.qualcomm.com with ESMTP/TLS/AES256-SHA; 06 Mar 2020 12:17:33 +0530 Received: from c-skakit-linux.qualcomm.com ([10.242.50.210]) by ironmsg01-blr.qualcomm.com with ESMTP; 06 Mar 2020 12:17:17 +0530 Received: by c-skakit-linux.qualcomm.com (Postfix, from userid 2344709) id 4E2CA3A24; Fri, 6 Mar 2020 12:17:16 +0530 (IST) From: satya priya To: gregkh@linuxfoundation.org Cc: swboyd@chromium.org, mgautam@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, akashast@codeaurora.org, rojay@codeaurora.org, msavaliy@qti.qualcomm.com, satya priya Subject: [PATCH V3 1/2] tty: serial: qcom_geni_serial: Allocate port->rx_fifo buffer in probe Date: Fri, 6 Mar 2020 12:17:07 +0530 Message-Id: <1583477228-32231-2-git-send-email-skakit@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1583477228-32231-1-git-send-email-skakit@codeaurora.org> References: <1583477228-32231-1-git-send-email-skakit@codeaurora.org> Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org To fix the RX cancel command failure, rx_fifo buffer needs to be flushed in stop_rx() by calling handle_rx().In handle_rx() the data in rx_fifo buffer is read and then dropped, not sent to upper layers. If set_termios is called before startup, by this time memory is not allocated to port->rx_fifo buffer, which leads to a NULL pointer dereference. To avoid this NULL pointer dereference allocate memory to port->rx_fifo in probe itself. Signed-off-by: satya priya Reported-by: Stephen Boyd --- Changes in V3: - As per Stephen's comment, change the declaration of rx_fifo pointer to void pointer. drivers/tty/serial/qcom_geni_serial.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 191abb1..f74f8a8 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -113,7 +113,7 @@ struct qcom_geni_serial_port { unsigned int baud; unsigned int tx_bytes_pw; unsigned int rx_bytes_pw; - u32 *rx_fifo; + void *rx_fifo; u32 loopback; bool brk; @@ -504,7 +504,6 @@ static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop) static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop) { - unsigned char *buf; struct tty_port *tport; struct qcom_geni_serial_port *port = to_dev_port(uport, uport); u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE; @@ -516,8 +515,7 @@ static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop) if (drop) return 0; - buf = (unsigned char *)port->rx_fifo; - ret = tty_insert_flip_string(tport, buf, bytes); + ret = tty_insert_flip_string(tport, port->rx_fifo, bytes); if (ret != bytes) { dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n", __func__, ret, bytes); @@ -858,12 +856,6 @@ static int qcom_geni_serial_port_setup(struct uart_port *uport) false, false, true); geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2); geni_se_select_mode(&port->se, GENI_SE_FIFO); - if (!uart_console(uport)) { - port->rx_fifo = devm_kcalloc(uport->dev, - port->rx_fifo_depth, sizeof(u32), GFP_KERNEL); - if (!port->rx_fifo) - return -ENOMEM; - } port->setup = true; return 0; @@ -1274,6 +1266,13 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS; port->tx_fifo_width = DEF_FIFO_WIDTH_BITS; + if (!console) { + port->rx_fifo = devm_kcalloc(uport->dev, + port->rx_fifo_depth, sizeof(u32), GFP_KERNEL); + if (!port->rx_fifo) + return -ENOMEM; + } + port->name = devm_kasprintf(uport->dev, GFP_KERNEL, "qcom_geni_serial_%s%d", uart_console(uport) ? "console" : "uart", uport->line);