Re: [PATCH] Change judgment len position

From: Fengguang Wu
Date: Wed Oct 24 2018 - 21:11:17 EST

CC Philip and LKP team.

On Wed, Oct 24, 2018 at 04:46:18PM -0700, Joe Perches wrote:
(adding Fengguang Wu and lkp)

On Wed, 2018-10-24 at 22:48 +0200, Willy Tarreau wrote:
When you read this patch from an apparent first-time contributor (no
trace in either LKML, netdev or even google), the level of assurance
in the commit message is pretty good, showing that he's not at all a
beginner, which doesn't match at all the type of error seen in the
code, which doesn't even need to be compiled to see that it will emit
a warning and not work as advertised.

Which to me is more of an indication of beginner-ness.

When you factor in the fact that the code opens a big but very discrete
vulnerability, I tend to think that in fact we're not facing a newbie
at all but someone deliberately trying to inject a subtle backdoor into
the kernel and disguise it as a vague bug fix,

That seems unlikely as it introduces a compilation warning.

A real intentional backdoor from a nefarious source would
likely be completely correct about compilation and use the
typical commit subject style.

Anyway, who know for certain right now.

I would have suggested David reply with only his second sentence
and maybe a pointer to kernelnewbies or staging.

Just something like:

nack: 'len' has no value before the get_user() call.

Please try to make your first patch in drivers/staging
to get familiar with submitting patches to the kernel.

Maybe there's utility in creating a filtering and auto-reply
tool for first time patch submitters for all the vger mailing
lists using some combination of previously known submitters
and the 0-day robot to point those first time submitters of
defective patches to kernelnewbies and staging.

Yeah good idea. That feature can be broken into 2 parts:

- an email script, which could be added to Linux scripts/ dir - maintain records for telling whether someone is first-time patch submitters