Re: [PATCH 5.15] usb: gadget: u_ether: fix regression in setting fixed MAC address

From: Greg Kroah-Hartman
Date: Thu Jun 23 2022 - 11:53:09 EST


On Wed, Jun 22, 2022 at 11:18:04PM +0300, Marian Postevca wrote:
> commit b337af3a4d6147000b7ca6b3438bf5c820849b37 upstream.
>
> In systemd systems setting a fixed MAC address through
> the "dev_addr" module argument fails systematically.
> When checking the MAC address after the interface is created
> it always has the same but different MAC address to the one
> supplied as argument.
>
> This is partially caused by systemd which by default will
> set an internally generated permanent MAC address for interfaces
> that are marked as having a randomly generated address.
>
> Commit 890d5b40908bfd1a ("usb: gadget: u_ether: fix race in
> setting MAC address in setup phase") didn't take into account
> the fact that the interface must be marked as having a set
> MAC address when it's set as module argument.
>
> Fixed by marking the interface with NET_ADDR_SET when
> the "dev_addr" module argument is supplied.
>
> Reported-by: Maximilian Senftleben <kernel@xxxxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 890d5b40908bfd1a ("usb: gadget: u_ether: fix race in setting MAC address in setup phase")
> Signed-off-by: Marian Postevca <posteuca@xxxxxxxxx>
> ---
> drivers/usb/gadget/function/u_ether.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)

All now queued up, thanks.

greg k-h