Re: Problem using AF_PACKET with SOCK_RAW on ieee802514 devices

[Josef Filzmaier <j.filzmaier@gmx.at>]

On Donnerstag, 14. Juni 2018 16:20:36 CEST you wrote:
> On Thu, Jun 14, 2018 at 12:35:40AM +0200, Josef Filzmaier wrote:
> > Hello everyone (again)!
> > 
> > I am using the linux-wpan stack with the atusb and at86rf230 drivers
> > (rf212). Moreover i am using raw sockets to test some userspace
> > implemenation of a custom protocol. In userspace i am using (attention,
> > golang ahead)> 
> > > protocol = htons(syscall.ETH_P_IEEE802154)
> > > syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, int(protocol))
> > 
> > to create a raw socket. This has been working as desired up until commit
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/
> > ?
> > id=b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba
> > 
> > After this commit the kernel mistakenly attaches two uninitialized bytes
> > at
> > the end of my raw data. I am currently using a patched kernel which uses
> > the following code in af_packet.c (Modified the else if over Willem de
> > Brujin's patch)
> > 
> > > } else if (sock->type != SOCK_RAW && reserve {
> > > 
> > > 	skb_push(skb, reserve);
> > > 
> > > }
> 
> Check commit 9aad13b087ab ("packet: fix reserve calculation").
> 
> Push is definitely wrong here and breaks things. dev_hard_header_len is
> the minimum size what we allow to the driver level.
> 
> This should be 3 (can you please check that if it's 2 or 3 I think there
> was some off-by one fix lately and I had it on the list).
> 
> It's because drivers parse FC and SEQ, this is what I have in the
> architecture yet. There exists drivers which doing more but this is a
> whole other big issue.
> 
> - Alex

Yes, applying 9aad13b087ab also fixes my problem. 

> This should be 3 (can you please check that if it's 2 or 3 I think there
> was some off-by one fix lately and I had it on the list).

I just tested, dev->hard_header_len = 2

When is this patch going to be applied to the mainline kernel? Is there any 
way in which i can know that it will be applied to the 4.16.x series?

Thanks,
Josef

-- 
Filzmaier Josef