kernel-janitors.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Jarod Wilson <jarod@redhat.com>,
	Ben Hutchings <ben@decadent.org.uk>,
	Luis Henriques <luis.henriques@canonical.com>,
	linux-media@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [patch] [media] rc: divide by zero bugs in s_tx_carrier()
Date: Sat, 18 Aug 2012 15:58:50 +0000	[thread overview]
Message-ID: <20120818155850.GA11819@elgon.mountain> (raw)

"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 <dan.carpenter@oracle.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_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);

             reply	other threads:[~2012-08-18 15:58 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-18 15:58 Dan Carpenter [this message]
2012-08-19 19:29 ` [patch] [media] rc: divide by zero bugs in s_tx_carrier() Ben Hutchings

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20120818155850.GA11819@elgon.mountain \
    --to=dan.carpenter@oracle.com \
    --cc=ben@decadent.org.uk \
    --cc=jarod@redhat.com \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=luis.henriques@canonical.com \
    --cc=mchehab@infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).