3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Firo Yang <fir...@gmail.com>
[ Upstream commit fb3ce90b7d7761b6f7f28f0ff5c456ef6b5229a1 ]
syszkaller fuzzer triggered a divide by zero, when set calibration
through ioctl().
To fix it, test 'bitrate' if it is negative or 0, just return -EINVAL.
Reported-by: Andrey Konovalov <andreyk...@google.com>
Signed-off-by: Firo Yang <fir...@gmail.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/net/hamradio/hdlcdrv.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/net/hamradio/hdlcdrv.c
+++ b/drivers/net/hamradio/hdlcdrv.c
@@ -571,6 +571,8 @@ static int hdlcdrv_ioctl(struct net_devi
case HDLCDRVCTL_CALIBRATE:
if(!capable(CAP_SYS_RAWIO))
return -EPERM;
+ if (s->par.bitrate <= 0)
+ return -EINVAL;
if (bi.data.calibrate > INT_MAX / s->par.bitrate)
return -EINVAL;
s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
