USB: ums_realtek: do not use stack memory for DMA in __do_config_autodelink

__do_config_autodelink passes the data variable to the transport function.
If the calling functions pass a stack variable, this will eventually trigger
a DMA-API debug backtrace for mapping stack memory in the DMA buffer.  Fix
this by calling kmemdup for the passed data instead.

Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
jwboyer@redhat.com 2012-02-20 15:34:34 -05:00 committed by Greg Kroah-Hartman
parent 28c56ea143
commit 4898e07174

View File

@ -507,9 +507,14 @@ static int __do_config_autodelink(struct us_data *us, u8 *data, u16 len)
{
int retval;
u8 cmnd[12] = {0};
u8 *buf;
US_DEBUGP("%s, addr = 0xfe47, len = %d\n", __FUNCTION__, len);
buf = kmemdup(data, len, GFP_NOIO);
if (!buf)
return USB_STOR_TRANSPORT_ERROR;
cmnd[0] = 0xF0;
cmnd[1] = 0x0E;
cmnd[2] = 0xfe;
@ -517,7 +522,8 @@ static int __do_config_autodelink(struct us_data *us, u8 *data, u16 len)
cmnd[4] = (u8)(len >> 8);
cmnd[5] = (u8)len;
retval = rts51x_bulk_transport_special(us, 0, cmnd, 12, data, len, DMA_TO_DEVICE, NULL);
retval = rts51x_bulk_transport_special(us, 0, cmnd, 12, buf, len, DMA_TO_DEVICE, NULL);
kfree(buf);
if (retval != USB_STOR_TRANSPORT_GOOD) {
return -EIO;
}