1 files changed, 34 insertions, 25 deletions

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 9ad44a96dfe3..871cdccf3a5f 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -2480,12 +2480,12 @@ static int ftdi_prepare_write_buffer(struct usb_serial_port *port,
 #define FTDI_RS_ERR_MASK (FTDI_RS_BI | FTDI_RS_PE | FTDI_RS_FE | FTDI_RS_OE)
 
 static int ftdi_process_packet(struct usb_serial_port *port,
-		struct ftdi_private *priv, char *packet, int len)
+		struct ftdi_private *priv, unsigned char *buf, int len)
 {
+	unsigned char status;
+	bool brkint = false;
 	int i;
-	char status;
 	char flag;
-	char *ch;
 
 	if (len < 2) {
 		dev_dbg(&port->dev, "malformed packet\n");
@@ -2495,7 +2495,7 @@ static int ftdi_process_packet(struct usb_serial_port *port,
 	/* Compare new line status to the old one, signal if different/
 	   N.B. packet may be processed more than once, but differences
 	   are only processed once.  */
-	status = packet[0] & FTDI_STATUS_B0_MASK;
+	status = buf[0] & FTDI_STATUS_B0_MASK;
 	if (status != priv->prev_status) {
 		char diff_status = status ^ priv->prev_status;
 
@@ -2521,13 +2521,12 @@ static int ftdi_process_packet(struct usb_serial_port *port,
 	}
 
 	/* save if the transmitter is empty or not */
-	if (packet[1] & FTDI_RS_TEMT)
+	if (buf[1] & FTDI_RS_TEMT)
 		priv->transmit_empty = 1;
 	else
 		priv->transmit_empty = 0;
 
-	len -= 2;
-	if (!len)
+	if (len == 2)
 		return 0;	/* status only */
 
 	/*
@@ -2535,47 +2534,57 @@ static int ftdi_process_packet(struct usb_serial_port *port,
 	 * data payload to avoid over-reporting.
 	 */
 	flag = TTY_NORMAL;
-	if (packet[1] & FTDI_RS_ERR_MASK) {
-		/* Break takes precedence over parity, which takes precedence
-		 * over framing errors */
-		if (packet[1] & FTDI_RS_BI) {
-			flag = TTY_BREAK;
+	if (buf[1] & FTDI_RS_ERR_MASK) {
+		/*
+		 * Break takes precedence over parity, which takes precedence
+		 * over framing errors. Note that break is only associated
+		 * with the last character in the buffer and only when it's a
+		 * NUL.
+		 */
+		if (buf[1] & FTDI_RS_BI && buf[len - 1] == '\0') {
 			port->icount.brk++;
-			usb_serial_handle_break(port);
-		} else if (packet[1] & FTDI_RS_PE) {
+			brkint = true;
+		}
+		if (buf[1] & FTDI_RS_PE) {
 			flag = TTY_PARITY;
 			port->icount.parity++;
-		} else if (packet[1] & FTDI_RS_FE) {
+		} else if (buf[1] & FTDI_RS_FE) {
 			flag = TTY_FRAME;
 			port->icount.frame++;
 		}
 		/* Overrun is special, not associated with a char */
-		if (packet[1] & FTDI_RS_OE) {
+		if (buf[1] & FTDI_RS_OE) {
 			port->icount.overrun++;
 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
 		}
 	}
 
-	port->icount.rx += len;
-	ch = packet + 2;
+	port->icount.rx += len - 2;
 
-	if (port->port.console && port->sysrq) {
-		for (i = 0; i < len; i++, ch++) {
-			if (!usb_serial_handle_sysrq_char(port, *ch))
-				tty_insert_flip_char(&port->port, *ch, flag);
+	if (brkint || port->sysrq) {
+		for (i = 2; i < len; i++) {
+			if (brkint && i == len - 1) {
+				if (usb_serial_handle_break(port))
+					return len - 3;
+				flag = TTY_BREAK;
+			}
+			if (usb_serial_handle_sysrq_char(port, buf[i]))
+				continue;
+			tty_insert_flip_char(&port->port, buf[i], flag);
 		}
 	} else {
-		tty_insert_flip_string_fixed_flag(&port->port, ch, flag, len);
+		tty_insert_flip_string_fixed_flag(&port->port, buf + 2, flag,
+				len - 2);
 	}
 
-	return len;
+	return len - 2;
 }
 
 static void ftdi_process_read_urb(struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
 	struct ftdi_private *priv = usb_get_serial_port_data(port);
-	char *data = (char *)urb->transfer_buffer;
+	char *data = urb->transfer_buffer;
 	int i;
 	int len;
 	int count = 0;