usx2y: don't bother with access_ok() in ->dsp_load()

memdup_user() checks it, so the only effect would be failing with
-EINVAL instead of -EFAULT in case when access_ok() is false.
However, the caller has already checked access_ok() itself (and
would have buggered off with -EFAULT), so the check is completely
pointless.  Removing it both simplifies the only instance
of ->dsp_load() and allows to get rid of the check in caller -
its sole effect used to be in preventing a bogus error value
from access_ok() in the instance.  Let memdup_user() do the
right thing instead...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2017-12-28 14:43:06 -05:00
parent 3d26759c09
commit fc1c428eb4

View File

@ -198,24 +198,22 @@ static int snd_usX2Y_hwdep_dsp_load(struct snd_hwdep *hw,
struct snd_hwdep_dsp_image *dsp)
{
struct usX2Ydev *priv = hw->private_data;
int lret, err = -EINVAL;
struct usb_device* dev = priv->dev;
int lret, err;
char *buf;
snd_printdd( "dsp_load %s\n", dsp->name);
if (access_ok(VERIFY_READ, dsp->image, dsp->length)) {
struct usb_device* dev = priv->dev;
char *buf;
buf = memdup_user(dsp->image, dsp->length);
if (IS_ERR(buf))
return PTR_ERR(buf);
buf = memdup_user(dsp->image, dsp->length);
if (IS_ERR(buf))
return PTR_ERR(buf);
err = usb_set_interface(dev, 0, 1);
if (err)
snd_printk(KERN_ERR "usb_set_interface error \n");
else
err = usb_bulk_msg(dev, usb_sndbulkpipe(dev, 2), buf, dsp->length, &lret, 6000);
kfree(buf);
}
err = usb_set_interface(dev, 0, 1);
if (err)
snd_printk(KERN_ERR "usb_set_interface error \n");
else
err = usb_bulk_msg(dev, usb_sndbulkpipe(dev, 2), buf, dsp->length, &lret, 6000);
kfree(buf);
if (err)
return err;
if (dsp->index == 1) {