This is a note to let you know that I've just added the patch titled
hdlcdrv: Fix divide by zero in hdlcdrv_ioctl
to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: hdlcdrv-fix-divide-by-zero-in-hdlcdrv_ioctl.patch and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Tue Apr 10 10:31:53 CEST 2018
From: Firo Yang firogm@gmail.com Date: Fri, 26 May 2017 22:37:38 +0800 Subject: hdlcdrv: Fix divide by zero in hdlcdrv_ioctl
From: Firo Yang firogm@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 andreyknvl@google.com Signed-off-by: Firo Yang firogm@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@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 @@ -574,6 +574,8 @@ 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;
Patches currently in stable-queue which might be from firogm@gmail.com are
queue-4.4/hdlcdrv-fix-divide-by-zero-in-hdlcdrv_ioctl.patch