Re: [[PATCH v1]] hdlcdrv: fix divide error bug if bitrate is 0
From: Andrey Konovalov <hidden>
Date: 2017-05-19 00:31:56
Also in:
linux-hams
On Thu, May 18, 2017 at 6:02 AM, Firo Yang [off-list ref] wrote:
The divisor s->par.bitrate will always be 0 until initialized by ndo_open() and hdlcdrv_open(). In order to fix this divide zero error, check whether the netdevice was opened by ndo_open() before performing divide.And we also check the the value of bitrate in case of bad setting of it. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Firo Yang <redacted>
Hi Firo, Please reply to the original report thread when you send a fix, so other people won't start working on the same patch. BTW, it was reported by me, but I don't think it's important. Thanks!
quoted hunk ↗ jump to hunk
--- v0->v1: Reviewed by walter harms [off-list ref]. Return ENODEV instead of EPERM if !netif_running(dev) Check if s->par.bitrate > 0. drivers/net/hamradio/hdlcdrv.c | 4 ++++ 1 file changed, 4 insertions(+)diff --git a/drivers/net/hamradio/hdlcdrv.c b/drivers/net/hamradio/hdlcdrv.c index 8c3633c..b0f417f 100644 --- a/drivers/net/hamradio/hdlcdrv.c +++ b/drivers/net/hamradio/hdlcdrv.c@@ -576,6 +576,10 @@ static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) case HDLCDRVCTL_CALIBRATE: if(!capable(CAP_SYS_RAWIO)) return -EPERM; + if (!netif_running(dev)) + return -ENODEV; + 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; --2.7.4 -- You received this message because you are subscribed to the Google Groups "syzkaller" group. To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller+unsubscribe@googlegroups.com. For more options, visit https://groups.google.com/d/optout.