redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

USB: mos7840: fix DMA to stack

Browse source 
Fix regression introduced by commit 0eafe4de1a ("USB: serial: mos7840:
add support for MCS7810 devices") which used stack-allocated buffers for
control messages.

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2013-05-27 14:44:40 +02:00 committed by Greg Kroah-Hartman
parent 72ea18a558
commit 15ee89c334
1 changed files with 27 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

35
drivers/usb/serial/mos7840.c
View file

@ -2142,13 +2142,21 @@ static int mos7840_ioctl(struct tty_struct *tty,
static int mos7810_check(struct usb_serial *serial)
{
int i, pass_count = 0;
u8 *buf;
__u16 data = 0, mcr_data = 0;
__u16 test_pattern = 0x55AA;
int res;
buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
if (!buf)
return 0; /* failed to identify 7810 */
/* Store MCR setting */
usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
MCS_RDREQ, MCS_RD_RTYPE, 0x0300, MODEM_CONTROL_REGISTER,
&mcr_data, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
if (res == VENDOR_READ_LENGTH)
mcr_data = *buf;
for (i = 0; i < 16; i++) {
/* Send the 1-bit test pattern out to MCS7810 test pin */
@ -2158,9 +2166,12 @@ static int mos7810_check(struct usb_serial *serial)
MODEM_CONTROL_REGISTER, NULL, 0, MOS_WDR_TIMEOUT);
/* Read the test pattern back */
usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, &data,
VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
res = usb_control_msg(serial->dev,
usb_rcvctrlpipe(serial->dev, 0), MCS_RDREQ,
MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
if (res == VENDOR_READ_LENGTH)
data = *buf;
/* If this is a MCS7810 device, both test patterns must match */
if (((test_pattern >> i) ^ (~data >> 1)) & 0x0001)
@ -2174,6 +2185,8 @@ static int mos7810_check(struct usb_serial *serial)
MCS_WR_RTYPE, 0x0300 | mcr_data, MODEM_CONTROL_REGISTER, NULL,
0, MOS_WDR_TIMEOUT);
kfree(buf);
if (pass_count == 16)
return 1;
@ -2183,11 +2196,17 @@ static int mos7810_check(struct usb_serial *serial)
static int mos7840_calc_num_ports(struct usb_serial *serial)
{
__u16 data = 0x00;
u8 *buf;
int mos7840_num_ports;
usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, &data,
VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
buf = kzalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
if (buf) {
usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
data = *buf;
kfree(buf);
}
if (serial->dev->descriptor.idProduct == MOSCHIP_DEVICE_ID_7810 ||
serial->dev->descriptor.idProduct == MOSCHIP_DEVICE_ID_7820) {