[media] rc: divide by zero bugs in s_tx_carrier()

"carrier" comes from a get_user() in ir_lirc_ioctl().  We need to test
that it's not zero before using it as a divisor.  It might have been
nice to test for this ir_lirc_ioctl() but the mceusb driver uses zero to
disable carrier modulation.
The bug in redrat3 is a little more subtle.  The ->carrier is passed to
mod_freq_to_val() which uses it as a divisor.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Dan Carpenter
2012-09-11 07:11:24 -03:00
committed by Mauro Carvalho Chehab
parent a52eb6c02f
commit 48cafec9a9
3 changed files with 10 additions and 1 deletions

View File

@@ -881,10 +881,13 @@ static int ene_set_tx_mask(struct rc_dev *rdev, u32 tx_mask)
static int ene_set_tx_carrier(struct rc_dev *rdev, u32 carrier)
{
struct ene_device *dev = rdev->priv;
u32 period = 2000000 / carrier;
u32 period;
dbg("TX: attempt to set tx carrier to %d kHz", carrier);
if (carrier == 0)
return -EINVAL;
period = 2000000 / carrier;
if (period && (period > ENE_CIRMOD_PRD_MAX ||
period < ENE_CIRMOD_PRD_MIN)) {