diff options
| author | Dan Carpenter <dan.carpenter@oracle.com> | 2012-09-11 07:11:24 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2012-10-06 09:24:39 -0300 |
| commit | 48cafec9a941c2dfe94d76642662bc20bf87fe08 (patch) | |
| tree | 135943901bfccdb6a8e260fed60c6583fcc8021b | |
| parent | a52eb6c02fa27efb5f8980312785fce1f77377e2 (diff) | |
[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>
| -rw-r--r-- | drivers/media/rc/ene_ir.c | 5 | ||||
| -rw-r--r-- | drivers/media/rc/nuvoton-cir.c | 3 | ||||
| -rw-r--r-- | drivers/media/rc/redrat3.c | 3 |
3 files changed, 10 insertions, 1 deletions
diff --git a/drivers/media/rc/ene_ir.c b/drivers/media/rc/ene_ir.c index 647dd951b0e8..d05ac15b5de4 100644 --- a/drivers/media/rc/ene_ir.c +++ b/drivers/media/rc/ene_ir.c @@ -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)) { diff --git a/drivers/media/rc/nuvoton-cir.c b/drivers/media/rc/nuvoton-cir.c index 699eef39128b..2ea913a44ae8 100644 --- a/drivers/media/rc/nuvoton-cir.c +++ b/drivers/media/rc/nuvoton-cir.c @@ -517,6 +517,9 @@ static int nvt_set_tx_carrier(struct rc_dev *dev, u32 carrier) 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 49731b1a9c57..9f5a17bb5ef5 100644 --- a/drivers/media/rc/redrat3.c +++ b/drivers/media/rc/redrat3.c @@ -890,6 +890,9 @@ static int redrat3_set_tx_carrier(struct rc_dev *rcdev, u32 carrier) struct device *dev = rr3->dev; rr3_dbg(dev, "Setting modulation frequency to %u", carrier); + if (carrier == 0) + return -EINVAL; + rr3->carrier = carrier; return carrier; |