summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSean Young <sean@mess.org>2021-01-19 14:53:50 +0100
committerMauro Carvalho Chehab <mchehab+huawei@kernel.org>2021-01-27 08:28:36 +0100
commit9dec0f48a75e0dadca498002d25ef4e143e60194 (patch)
tree36ae132a069acc1d012b566b18fadbdc9b06451b
parentmedia: sunxi-cir: Implement suspend/resume/shutdown callbacks (diff)
downloadlinux-9dec0f48a75e0dadca498002d25ef4e143e60194.tar.xz
linux-9dec0f48a75e0dadca498002d25ef4e143e60194.zip
media: mceusb: sanity check for prescaler value
prescaler larger than 8 would mean the carrier is at most 152Hz, which does not make sense for IR carriers. Reported-by: syzbot+6d31bf169a8265204b8d@syzkaller.appspotmail.com Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
-rw-r--r--drivers/media/rc/mceusb.c9
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c
index c8d63673e131..5642595a057e 100644
--- a/drivers/media/rc/mceusb.c
+++ b/drivers/media/rc/mceusb.c
@@ -701,11 +701,18 @@ static void mceusb_dev_printdata(struct mceusb_dev *ir, u8 *buf, int buf_len,
data[0], data[1]);
break;
case MCE_RSP_EQIRCFS:
+ if (!data[0] && !data[1]) {
+ dev_dbg(dev, "%s: no carrier", inout);
+ break;
+ }
+ // prescaler should make sense
+ if (data[0] > 8)
+ break;
period = DIV_ROUND_CLOSEST((1U << data[0] * 2) *
(data[1] + 1), 10);
if (!period)
break;
- carrier = (1000 * 1000) / period;
+ carrier = USEC_PER_SEC / period;
dev_dbg(dev, "%s carrier of %u Hz (period %uus)",
inout, carrier, period);
break;