From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Sat, 18 Aug 2012 15:58:50 +0000 Subject: [patch] [media] rc: divide by zero bugs in s_tx_carrier() Message-Id: <20120818155850.GA11819@elgon.mountain> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Mauro Carvalho Chehab Cc: Jarod Wilson , Ben Hutchings , Luis Henriques , linux-media@vger.kernel.org, kernel-janitors@vger.kernel.org "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. Signed-off-by: Dan Carpenter 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_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 699eef3..2ea913a 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);