USB: mos7840: fix memory leak in open

commit 5f8a2e68 upstream.

Allocated urbs and buffers were never freed on errors in open.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/mos7840.c

@@ -923,20 +923,20 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
 	if (status < 0) {
 		dbg("Reading Spreg failed");
-		return -1;
+		goto err;
 	}
 	Data |= 0x80;
 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
 	if (status < 0) {
 		dbg("writing Spreg failed");
-		return -1;
+		goto err;
 	}
 
 	Data &= ~0x80;
 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
 	if (status < 0) {
 		dbg("writing Spreg failed");
-		return -1;
+		goto err;
 	}
 	/* End of block to be checked */
 
@@ -945,7 +945,7 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 									&Data);
 	if (status < 0) {
 		dbg("Reading Controlreg failed");
-		return -1;
+		goto err;
 	}
 	Data |= 0x08;		/* Driver done bit */
 	Data |= 0x20;		/* rx_disable */
@@ -953,7 +953,7 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 				mos7840_port->ControlRegOffset, Data);
 	if (status < 0) {
 		dbg("writing Controlreg failed");
-		return -1;
+		goto err;
 	}
 	/* do register settings here */
 	/* Set all regs to the device default values. */
@@ -964,21 +964,21 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
 	if (status < 0) {
 		dbg("disabling interrupts failed");
-		return -1;
+		goto err;
 	}
 	/* Set FIFO_CONTROL_REGISTER to the default value */
 	Data = 0x00;
 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
 	if (status < 0) {
 		dbg("Writing FIFO_CONTROL_REGISTER  failed");
-		return -1;
+		goto err;
 	}
 
 	Data = 0xcf;
 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
 	if (status < 0) {
 		dbg("Writing FIFO_CONTROL_REGISTER  failed");
-		return -1;
+		goto err;
 	}
 
 	Data = 0x03;
@@ -1134,7 +1134,15 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 	dbg ("%s leave", __func__);
 
 	return 0;
-
+err:
+	for (j = 0; j < NUM_URBS; ++j) {
+		urb = mos7840_port->write_urb_pool[j];
+		if (!urb)
+			continue;
+		kfree(urb->transfer_buffer);
+		usb_free_urb(urb);
+	}
+	return status;
 }
 
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