Re: Xenomai 4 / oob_sendmsg crashes kernel from tidbits/oob-net-icmp

[Philippe Gerum <rpm@xenomai.org>]

Sri Subramanian <sridhar.subramanian@gmail.com> writes:

> Hello,
>
> I am trying to optimize sending ethernet raw packets (for an Ethercat
> fieldbus application) on a RaspberryPi/CM4 environment.
>
> Before implementing the application, I thought I'd try getting an ICMP
> echo using the "tidbits" sample program oob-net-icmp.
>
> I am using eth0 from a RaspberryPI (used to ping) connected to another
> PI device (CM4 on an IO board) also on eth0, which is echoing back the
> pings using oob-net-icmp. I set up vlan 42 as documented in the
> program, for both the devices. (I verify the network connection is
> good  prior to this by sending pings and verifying the echo responses,
> through the standard Linux stack on eth0).
>
> I also set up the ping-receiving device so the Xenomai kernel can
> route the packets up the Xenomai mini stack, setting:
>
> echo 1> /sys/class/net/eth0.42/oob_port
> echo 42 > /sys/class/evl/control/net_vlans
>
> On the first ping, the kernel crashes with the stack as below. I've
> tested on both versions 5.15 and 5.17 (both with CONFIG_NET_OOB=y).
> Thanks for any help or guidance.
>

Thanks for reporting, I can reproduce this as well. Maybe a problem with
the prep/recycling of socket buffers. Investigating this bug is on my
todo list.

-- 
Philippe.