[media] lirc: validate transmission ir data
The lirc interface allows 255 u32 spaces and pulses, which are usec. If
the driver can handle this (e.g. winbond-cir) you can produce hours of
meaningless IR data and there is no method of interrupting it.
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/drivers/media/rc/ir-lirc-codec.c b/drivers/media/rc/ir-lirc-codec.c
index e456126..e5be920 100644
--- a/drivers/media/rc/ir-lirc-codec.c
+++ b/drivers/media/rc/ir-lirc-codec.c
@@ -140,11 +140,20 @@
goto out;
}
+ for (i = 0; i < count; i++) {
+ if (txbuf[i] > IR_MAX_DURATION / 1000 - duration || !txbuf[i]) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ duration += txbuf[i];
+ }
+
ret = dev->tx_ir(dev, txbuf, count);
if (ret < 0)
goto out;
- for (i = 0; i < ret; i++)
+ for (duration = i = 0; i < ret; i++)
duration += txbuf[i];
ret *= sizeof(unsigned int);