Re: [PATCH] sock filter: fix copy of filter from userspace

On Sat, 13 Oct 2012 21:19:49 +0200
Jiri Pirko [off-list ref] wrote:

Sat, Oct 13, 2012 at 08:40:32PM CEST, shemminger@vyatta.com wrote:

quoted

The sk_unattached_filter_create function is passed a socket
filter structure and the copies the contents of the filter from
userspace. Sparse detected that this code was incorrectly using
memcpy when it needed to use copy_from_user instead.

Hmm. fprog->filter is in this case allocated and filled in kernel.
So memcpy is good.

Not sure how to handle this correctly. Either we remove "__user" or we
redefine "struct sock_fprog" for sk_unattached_filter_create() use.

Any thoughts?

Or define a different structure for kernel usage versus userspace API.