[ 15/24] USB: mos7840: fix port-data memory leak

Greg Kroah-Hartman
2012-11-02T17:08:13Z

From: Johan Hovold <jhovold@gmail.com>

commit 80c00750f0c9867a65b30a17880939b6bc660a77 upstream.

Fix port-data memory leak by moving port data allocation and
deallocation to port_probe and port_remove.

Since commit 0998d0631001288 (device-core: Ensure drvdata = NULL when no
driver is bound) the port private data is no longer freed at release as
it is no longer accessible.

Note that the indentation was kept intact using a do-while(0) in order
to facilitate review. A follow-up patch will remove it.

Compile-only tested.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

This a backport of 80c00750f0c9867 from v3.7-rc to v3.6.5 as requested.

Thanks,
Johan

drivers/usb/serial/mos7840.c | 198 +++++++++++++++----------------------------
1 file changed, 71 insertions(+), 127 deletions(-)

--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -2405,52 +2405,43 @@ static int mos7840_calc_num_ports(struct
return mos7840_num_ports;
}

-/****************************************************************************
- * mos7840_startup
- ****************************************************************************/
-
-static int mos7840_startup(struct usb_serial *serial)
+static int mos7840_port_probe(struct usb_serial_port *port)
{
+ struct usb_serial *serial = port->serial;
struct moschip_port *mos7840_port;
- struct usb_device *dev;
- int i, status;
+ int status;
+ int pnum;
__u16 Data;

- if (!serial) {
- dbg("%s", "Invalid Handler");
- return -1;
- }
-
- dev = serial->dev;
-
/* we set up the pointers to the endpoints in the mos7840_open *
* function, as the structures aren't created yet. */

- /* set up port private structures */
- for (i = 0; i < serial->num_ports; ++i) {
- dbg ("mos7840_startup: configuring port %d............", i);
+ pnum = port->number - serial->minor;
+
+ /* FIXME: remove do-while(0) loop used to keep stable patch minimal.
+ */
+ do {
+ dbg("mos7840_startup: configuring port %d............", pnum);
mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
if (mos7840_port == NULL) {
- dev_err(&dev->dev, "%s - Out of memory\n", __func__);
- status = -ENOMEM;
- i--; /* don't follow NULL pointer cleaning up */
- goto error;
+ dev_err(&port->dev, "%s - Out of memory\n", __func__);
+ return -ENOMEM;
}

/* Initialize all port interrupt end point to port 0 int
* endpoint. Our device has only one interrupt end point
* common to all port */

- mos7840_port->port = serial->port[i];
- mos7840_set_port_private(serial->port[i], mos7840_port);
+ mos7840_port->port = port;
+ mos7840_set_port_private(port, mos7840_port);
spin_lock_init(&mos7840_port->pool_lock);

/* minor is not initialised until later by
* usb-serial.c:get_free_serial() and cannot therefore be used
* to index device instances */
- mos7840_port->port_num = i + 1;
- dbg ("serial->port[i]->number = %d", serial->port[i]->number);
- dbg ("serial->port[i]->serial->minor = %d", serial->port[i]->serial->minor);
+ mos7840_port->port_num = pnum + 1;
+ dbg("port->number = %d", port->number);
+ dbg("port->serial->minor = %d", port->serial->minor);
dbg ("mos7840_port->port_num = %d", mos7840_port->port_num);
dbg ("serial->minor = %d", serial->minor);

@@ -2480,10 +2471,10 @@ static int mos7840_startup(struct usb_se
mos7840_port->DcrRegOffset = 0x1c;
}
mos7840_dump_serial_port(mos7840_port);
- mos7840_set_port_private(serial->port[i], mos7840_port);
+ mos7840_set_port_private(port, mos7840_port);

/* enable rx_disable bit in control register */
- status = mos7840_get_reg_sync(serial->port[i],
+ status = mos7840_get_reg_sync(port,
mos7840_port->ControlRegOffset, &Data);
if (status < 0) {
dbg("Reading ControlReg failed status-0x%x", status);
@@ -2491,12 +2482,13 @@ static int mos7840_startup(struct usb_se
} else
dbg("ControlReg Reading success val is %x, status%d",
Data, status);
+
Data |= 0x08; /* setting driver done bit */
Data |= 0x04; /* sp1_bit to have cts change reflect in
modem status reg */

/* Data |= 0x20; //rx_disable bit */
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
mos7840_port->ControlRegOffset, Data);
if (status < 0) {
dbg("Writing ControlReg failed(rx_disable) status-0x%x", status);
@@ -2508,7 +2500,7 @@ static int mos7840_startup(struct usb_se
/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
and 0x24 in DCR3 */
Data = 0x01;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
(__u16) (mos7840_port->DcrRegOffset + 0), Data);
if (status < 0) {
dbg("Writing DCR0 failed status-0x%x", status);
@@ -2517,7 +2509,7 @@ static int mos7840_startup(struct usb_se
dbg("DCR0 Writing success status%d", status);

Data = 0x05;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
(__u16) (mos7840_port->DcrRegOffset + 1), Data);
if (status < 0) {
dbg("Writing DCR1 failed status-0x%x", status);
@@ -2526,7 +2518,7 @@ static int mos7840_startup(struct usb_se
dbg("DCR1 Writing success status%d", status);

Data = 0x24;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
(__u16) (mos7840_port->DcrRegOffset + 2), Data);
if (status < 0) {
dbg("Writing DCR2 failed status-0x%x", status);
@@ -2536,7 +2528,7 @@ static int mos7840_startup(struct usb_se

/* write values in clkstart0x0 and clkmulti 0x20 */
Data = 0x0;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
CLK_START_VALUE_REGISTER, Data);
if (status < 0) {
dbg("Writing CLK_START_VALUE_REGISTER failed status-0x%x", status);
@@ -2545,7 +2537,7 @@ static int mos7840_startup(struct usb_se
dbg("CLK_START_VALUE_REGISTER Writing success status%d", status);

Data = 0x20;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
CLK_MULTI_REGISTER, Data);
if (status < 0) {
dbg("Writing CLK_MULTI_REGISTER failed status-0x%x",
@@ -2557,7 +2549,7 @@ static int mos7840_startup(struct usb_se

/* write value 0x0 to scratchpad register */
Data = 0x00;
- status = mos7840_set_uart_reg(serial->port[i],
+ status = mos7840_set_uart_reg(port,
SCRATCH_PAD_REGISTER, Data);
if (status < 0) {
dbg("Writing SCRATCH_PAD_REGISTER failed status-0x%x",
@@ -2572,7 +2564,7 @@ static int mos7840_startup(struct usb_se
&& (serial->num_ports == 2)) {

Data = 0xff;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
(__u16) (ZLP_REG1 +
((__u16)mos7840_port->port_num)), Data);
dbg("ZLIP offset %x",
@@ -2580,14 +2572,14 @@ static int mos7840_startup(struct usb_se
((__u16) mos7840_port->port_num)));
if (status < 0) {
dbg("Writing ZLP_REG%d failed status-0x%x",
- i + 2, status);
+ pnum + 2, status);
break;
} else
dbg("ZLP_REG%d Writing success status%d",
- i + 2, status);
+ pnum + 2, status);
} else {
Data = 0xff;
- status = mos7840_set_reg_sync(serial->port[i],
+ status = mos7840_set_reg_sync(port,
(__u16) (ZLP_REG1 +
((__u16)mos7840_port->port_num) - 0x1), Data);
dbg("ZLIP offset %x",
@@ -2595,11 +2587,11 @@ static int mos7840_startup(struct usb_se
((__u16) mos7840_port->port_num) - 0x1));
if (status < 0) {
dbg("Writing ZLP_REG%d failed status-0x%x",
- i + 1, status);
+ pnum + 1, status);
break;
} else
dbg("ZLP_REG%d Writing success status%d",
- i + 1, status);
+ pnum + 1, status);

}
mos7840_port->control_urb = usb_alloc_urb(0, GFP_KERNEL);
@@ -2636,105 +2628,58 @@ static int mos7840_startup(struct usb_se
mos7840_port->led_flag = false;

/* Turn off LED */
- mos7840_set_led_sync(serial->port[i],
+ mos7840_set_led_sync(port,
MODEM_CONTROL_REGISTER, 0x0300);
}
- }
- dbg ("mos7840_startup: all ports configured...........");
+ } while (0);

- /* Zero Length flag enable */
- Data = 0x0f;
- status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
- if (status < 0) {
- dbg("Writing ZLP_REG5 failed status-0x%x", status);
- goto error;
- } else
- dbg("ZLP_REG5 Writing success status%d", status);
-
- /* setting configuration feature to one */
- usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
- (__u8) 0x03, 0x00, 0x01, 0x00, NULL, 0x00, MOS_WDR_TIMEOUT);
+ if (pnum == serial->num_ports - 1) {
+ dbg("mos7840_startup: all ports configured...........");
+
+ /* Zero Length flag enable */
+ Data = 0x0f;
+ status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
+ if (status < 0) {
+ dbg("Writing ZLP_REG5 failed status-0x%x", status);
+ goto error;
+ } else
+ dbg("ZLP_REG5 Writing success status%d", status);
+
+ /* setting configuration feature to one */
+ usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+ 0x03, 0x00, 0x01, 0x00, NULL, 0x00,
+ MOS_WDR_TIMEOUT);
+ }
return 0;
error:
- for (/* nothing */; i >= 0; i--) {
- mos7840_port = mos7840_get_port_private(serial->port[i]);
+ kfree(mos7840_port->dr);
+ kfree(mos7840_port->ctrl_buf);
+ usb_free_urb(mos7840_port->control_urb);
+ kfree(mos7840_port);

- kfree(mos7840_port->dr);
- kfree(mos7840_port->ctrl_buf);
- usb_free_urb(mos7840_port->control_urb);
- kfree(mos7840_port);
- }
return status;
}

-/****************************************************************************
- * mos7840_disconnect
- * This function is called whenever the device is removed from the usb bus.
- ****************************************************************************/
-
-static void mos7840_disconnect(struct usb_serial *serial)
+static int mos7840_port_remove(struct usb_serial_port *port)
{
- int i;
- unsigned long flags;
struct moschip_port *mos7840_port;

- if (!serial) {
- dbg("%s", "Invalid Handler");
- return;
- }
-
- /* check for the ports to be closed,close the ports and disconnect */
+ mos7840_port = mos7840_get_port_private(port);

- /* free private structure allocated for serial port *
- * stop reads and writes on all ports */
+ if (mos7840_port->has_led) {
+ /* Turn off LED */
+ mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);

- for (i = 0; i < serial->num_ports; ++i) {
- mos7840_port = mos7840_get_port_private(serial->port[i]);
- dbg ("mos7840_port %d = %p", i, mos7840_port);
- if (mos7840_port) {
- usb_kill_urb(mos7840_port->control_urb);
- }
+ del_timer_sync(&mos7840_port->led_timer1);
+ del_timer_sync(&mos7840_port->led_timer2);
}
-}
-
-/****************************************************************************
- * mos7840_release
- * This function is called when the usb_serial structure is freed.
- ****************************************************************************/
+ usb_kill_urb(mos7840_port->control_urb);
+ usb_free_urb(mos7840_port->control_urb);
+ kfree(mos7840_port->ctrl_buf);
+ kfree(mos7840_port->dr);
+ kfree(mos7840_port);

-static void mos7840_release(struct usb_serial *serial)
-{
- int i;
- struct moschip_port *mos7840_port;
-
- if (!serial) {
- dbg("%s", "Invalid Handler");
- return;
- }
-
- /* check for the ports to be closed,close the ports and disconnect */
-
- /* free private structure allocated for serial port *
- * stop reads and writes on all ports */
-
- for (i = 0; i < serial->num_ports; ++i) {
- mos7840_port = mos7840_get_port_private(serial->port[i]);
- dbg("mos7840_port %d = %p", i, mos7840_port);
- if (mos7840_port) {
- if (mos7840_port->has_led) {
- /* Turn off LED */
- mos7840_set_led_sync(mos7840_port->port,
- MODEM_CONTROL_REGISTER, 0x0300);
-
- del_timer_sync(&mos7840_port->led_timer1);
- del_timer_sync(&mos7840_port->led_timer2);
- }
- usb_free_urb(mos7840_port->control_urb);
- kfree(mos7840_port->ctrl_buf);
- kfree(mos7840_port->dr);
- kfree(mos7840_port);
- }
- }
+ return 0;
}

static struct usb_serial_driver moschip7840_4port_device = {
@@ -2762,9 +2707,8 @@ static struct usb_serial_driver moschip7
.tiocmget = mos7840_tiocmget,
.tiocmset = mos7840_tiocmset,
.get_icount = mos7840_get_icount,
- .attach = mos7840_startup,
- .disconnect = mos7840_disconnect,
- .release = mos7840_release,
+ .port_probe = mos7840_port_probe,
+ .port_remove = mos7840_port_remove,
.read_bulk_callback = mos7840_bulk_in_callback,
.read_int_callback = mos7840_interrupt_callback,
};