From: Liran Alon <LIRAN.ALON@xxxxxxxxxx>
Date: Tue, 20 Mar 2018 17:34:38 +0200
I personally don't understand why we should maintain
backwards-comparability to this behaviour.
The reason is because not breaking things is a cornerstone of Linux
kernel development.
This feature is not documented to user-mode and I don't see why it
is legit for the user to rely on it.
Whether it is documented or not is irrelevant. A lot of our
interfaces and behaviors are not documented or poorly documented
at best.
In addition, even if we do want to maintain backwards-comparability to
this behaviour, I think it is enough to have an opt-in flag in
/proc/sys/net/core/ that when set to 1 will activate the fix in
dev_forward_skb() provided by this patch. That would also be a very
simple change to the patch provided here.
Making it opt-in makes it more palatable, that's for sure.