On 09/07/2020 11:29, Dan Carpenter wrote:
This code reads from the array before verifying that "trig" is a valid index. If the index is wildly out of bounds then reading from an invalid address could lead to an Oops.Fixes: a8c66b684efa ("staging: comedi: addi_apci_1500: rewrite the subdevice support functions") Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com> --- drivers/staging/comedi/drivers/addi_apci_1500.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/staging/comedi/drivers/addi_apci_1500.c b/drivers/staging/comedi/drivers/addi_apci_1500.c index 45ad4ba92f94..689acd69a1b9 100644 --- a/drivers/staging/comedi/drivers/addi_apci_1500.c +++ b/drivers/staging/comedi/drivers/addi_apci_1500.c @@ -456,9 +456,9 @@ static int apci1500_di_cfg_trig(struct comedi_device *dev, unsigned int lo_mask = data[5] << shift; unsigned int chan_mask = hi_mask | lo_mask; unsigned int old_mask = (1 << shift) - 1; - unsigned int pm = devpriv->pm[trig] & old_mask; - unsigned int pt = devpriv->pt[trig] & old_mask; - unsigned int pp = devpriv->pp[trig] & old_mask; + unsigned int pm; + unsigned int pt; + unsigned int pp;if (trig > 1) {dev_dbg(dev->class_dev, @@ -471,6 +471,10 @@ static int apci1500_di_cfg_trig(struct comedi_device *dev, return -EINVAL; }+ pm = devpriv->pm[trig] & old_mask;+ pt = devpriv->pt[trig] & old_mask; + pp = devpriv->pp[trig] & old_mask; + switch (data[2]) { case COMEDI_DIGITAL_TRIG_DISABLE: /* clear trigger configuration */
Nice catch! Reviewed-by: Ian Abbott <abbo...@mev.co.uk> -- -=( Ian Abbott <abbo...@mev.co.uk> || Web: www.mev.co.uk )=- -=( MEV Ltd. is a company registered in England & Wales. )=- -=( Registered number: 02862268. Registered address: )=- -=( 15 West Park Road, Bramhall, STOCKPORT, SK7 3JZ, UK. )=- _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
