This is a note to let you know that I've just added the patch titled

net: cdc_ether: fix divide by 0 on bad descriptors

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: net-cdc_ether-fix-divide-by-0-on-bad-descriptors.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 Sun Nov 19 11:12:05 CET 2017

From: Bjørn Mork bjorn@mork.no Date: Mon, 6 Nov 2017 15:37:22 +0100 Subject: net: cdc_ether: fix divide by 0 on bad descriptors

From: Bjørn Mork bjorn@mork.no

commit 2cb80187ba065d7decad7c6614e35e07aec8a974 upstream.

Setting dev->hard_mtu to 0 will cause a divide error in usbnet_probe. Protect against devices with bogus CDC Ethernet functional descriptors by ignoring a zero wMaxSegmentSize.

Signed-off-by: Bjørn Mork bjorn@mork.no Acked-by: Oliver Neukum oneukum@suse.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/usb/cdc_ether.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/usb/cdc_ether.c +++ b/drivers/net/usb/cdc_ether.c @@ -221,7 +221,7 @@ skip: goto bad_desc; }

- if (header.usb_cdc_ether_desc) { + if (header.usb_cdc_ether_desc && info->ether->wMaxSegmentSize) { dev->hard_mtu = le16_to_cpu(info->ether->wMaxSegmentSize); /* because of Zaurus, we may be ignoring the host * side link address we were given.

Patches currently in stable-queue which might be from bjorn@mork.no are

queue-4.4/net-cdc_ether-fix-divide-by-0-on-bad-descriptors.patch queue-4.4/net-qmi_wwan-fix-divide-by-0-on-bad-descriptors.patch