The local variable 'bi' comes from userspace. If userspace passed a large number to 'bi.data.calibrate', there would be an integer overflow in the following line: s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
Signed-off-by: Wenliang Fan <fanwle...@gmail.com> --- drivers/net/hamradio/hdlcdrv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/hamradio/hdlcdrv.c b/drivers/net/hamradio/hdlcdrv.c index 3169252..5d78c1d 100644 --- a/drivers/net/hamradio/hdlcdrv.c +++ b/drivers/net/hamradio/hdlcdrv.c @@ -571,6 +571,8 @@ static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) case HDLCDRVCTL_CALIBRATE: if(!capable(CAP_SYS_RAWIO)) return -EPERM; + if (bi.data.calibrate > INT_MAX / s->par.bitrate) + return -EINVAL; s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16; return 0; -- 1.8.5.rc1.28.g7061504 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/