mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 11:19:37 +00:00
staging: comedi: addi_apci_1032: check INSN_CONFIG_DIGITAL_TRIG shift
The `INSN_CONFIG` comedi instruction with sub-instruction code
`INSN_CONFIG_DIGITAL_TRIG` includes a base channel in `data[3]`. This is
used as a right shift amount for other bitmask values without being
checked. Shift amounts greater than or equal to 32 will result in
undefined behavior. Add code to deal with this.
Fixes: 33cdce6293
("staging: comedi: addi_apci_1032: conform to new INSN_CONFIG_DIGITAL_TRIG")
Cc: <stable@vger.kernel.org> #3.8+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20200717145257.112660-3-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
f07804ec77
commit
0bd0db42a0
1 changed files with 14 additions and 6 deletions
|
@ -106,14 +106,22 @@ static int apci1032_cos_insn_config(struct comedi_device *dev,
|
|||
unsigned int *data)
|
||||
{
|
||||
struct apci1032_private *devpriv = dev->private;
|
||||
unsigned int shift, oldmask;
|
||||
unsigned int shift, oldmask, himask, lomask;
|
||||
|
||||
switch (data[0]) {
|
||||
case INSN_CONFIG_DIGITAL_TRIG:
|
||||
if (data[1] != 0)
|
||||
return -EINVAL;
|
||||
shift = data[3];
|
||||
oldmask = (1U << shift) - 1;
|
||||
if (shift < 32) {
|
||||
oldmask = (1U << shift) - 1;
|
||||
himask = data[4] << shift;
|
||||
lomask = data[5] << shift;
|
||||
} else {
|
||||
oldmask = 0xffffffffu;
|
||||
himask = 0;
|
||||
lomask = 0;
|
||||
}
|
||||
switch (data[2]) {
|
||||
case COMEDI_DIGITAL_TRIG_DISABLE:
|
||||
devpriv->ctrl = 0;
|
||||
|
@ -136,8 +144,8 @@ static int apci1032_cos_insn_config(struct comedi_device *dev,
|
|||
devpriv->mode2 &= oldmask;
|
||||
}
|
||||
/* configure specified channels */
|
||||
devpriv->mode1 |= data[4] << shift;
|
||||
devpriv->mode2 |= data[5] << shift;
|
||||
devpriv->mode1 |= himask;
|
||||
devpriv->mode2 |= lomask;
|
||||
break;
|
||||
case COMEDI_DIGITAL_TRIG_ENABLE_LEVELS:
|
||||
if (devpriv->ctrl != (APCI1032_CTRL_INT_ENA |
|
||||
|
@ -154,8 +162,8 @@ static int apci1032_cos_insn_config(struct comedi_device *dev,
|
|||
devpriv->mode2 &= oldmask;
|
||||
}
|
||||
/* configure specified channels */
|
||||
devpriv->mode1 |= data[4] << shift;
|
||||
devpriv->mode2 |= data[5] << shift;
|
||||
devpriv->mode1 |= himask;
|
||||
devpriv->mode2 |= lomask;
|
||||
break;
|
||||
default:
|
||||
return -EINVAL;
|
||||
|
|
Loading…
Reference in a new issue