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author | Sean Young <sean@mess.org> | 2021-01-19 14:53:50 +0100 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2021-01-27 08:28:36 +0100 |
commit | 9dec0f48a75e0dadca498002d25ef4e143e60194 (patch) | |
tree | 36ae132a069acc1d012b566b18fadbdc9b06451b | |
parent | media: sunxi-cir: Implement suspend/resume/shutdown callbacks (diff) | |
download | linux-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.c | 9 |
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; |