[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>
diff --git a/drivers/media/rc/ene_ir.c b/drivers/media/rc/ene_ir.c
index 647dd95..d05ac15 100644
--- a/drivers/media/rc/ene_ir.c
+++ b/drivers/media/rc/ene_ir.c
@@ -881,10 +881,13 @@
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)) {
diff --git a/drivers/media/rc/nuvoton-cir.c b/drivers/media/rc/nuvoton-cir.c
index 699eef3..2ea913a 100644
--- a/drivers/media/rc/nuvoton-cir.c
+++ b/drivers/media/rc/nuvoton-cir.c
@@ -517,6 +517,9 @@
struct nvt_dev *nvt = dev->priv;
u16 val;
+ if (carrier == 0)
+ return -EINVAL;
+
nvt_cir_reg_write(nvt, 1, CIR_CP);
val = 3000000 / (carrier) - 1;
nvt_cir_reg_write(nvt, val & 0xff, CIR_CC);
diff --git a/drivers/media/rc/redrat3.c b/drivers/media/rc/redrat3.c
index 49731b1..9f5a17b 100644
--- a/drivers/media/rc/redrat3.c
+++ b/drivers/media/rc/redrat3.c
@@ -890,6 +890,9 @@
struct device *dev = rr3->dev;
rr3_dbg(dev, "Setting modulation frequency to %u", carrier);
+ if (carrier == 0)
+ return -EINVAL;
+
rr3->carrier = carrier;
return carrier;