Commit f9d690b6 authored by satya priya's avatar satya priya Committed by Greg Kroah-Hartman
Browse files

tty: serial: qcom_geni_serial: Allocate port->rx_fifo buffer in probe 



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: default avatarsatya priya <skakit@codeaurora.org>
Reported-by: default avatarStephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1583477228-32231-2-git-send-email-skakit@codeaurora.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 9a8da608

drivers/tty/serial/qcom_geni_serial.c

+9 −10
Original line number Original line Diff line number Diff line
@@ -120,7 +120,7 @@ struct qcom_geni_serial_port { 
	unsigned int baud;

	unsigned int baud;

	unsigned int tx_bytes_pw;

	unsigned int tx_bytes_pw;

	unsigned int rx_bytes_pw;

	unsigned int rx_bytes_pw;

	u32 *rx_fifo;

	void *rx_fifo;

	u32 loopback;

	u32 loopback;

	bool brk;

	bool brk;
@@ -514,7 +514,6 @@ 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)

static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop)

{

{

	unsigned char *buf;

	struct tty_port *tport;

	struct tty_port *tport;

	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);

	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);

	u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE;

	u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE;
@@ -526,8 +525,7 @@ static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop) 
	if (drop)

	if (drop)

		return 0;

		return 0;





	buf = (unsigned char *)port->rx_fifo;

	ret = tty_insert_flip_string(tport, port->rx_fifo, bytes);

	ret = tty_insert_flip_string(tport, buf, bytes);

	if (ret != bytes) {

	if (ret != bytes) {

		dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n",

		dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n",

				__func__, ret, bytes);

				__func__, ret, bytes);
@@ -892,12 +890,6 @@ static int qcom_geni_serial_port_setup(struct uart_port *uport) 
						false, false, true);

						false, false, true);

	geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);

	geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);

	geni_se_select_mode(&port->se, GENI_SE_FIFO);

	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;

	port->setup = true;





	return 0;

	return 0;
@@ -1308,6 +1300,13 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) 
	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;

	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;

	port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;

	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,

	port->name = devm_kasprintf(uport->dev, GFP_KERNEL,

			"qcom_geni_serial_%s%d",

			"qcom_geni_serial_%s%d",

			uart_console(uport) ? "console" : "uart", uport->line);

			uart_console(uport) ? "console" : "uart", uport->line);

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