Re: [PATCH] Fix starting security procedures when not needed

[Johan Hedberg <johan.hedberg@gmail.com>]

Hi Luiz & Vinicius,

> > In any case, while writing this email, I realized that only checking
> > all bt_io_set() calls wasn't enough, so this patch may be incomplete.
> > All bt_io_listen() users should be safe, but there are some callers
> > of bt_io_connect() that may depend on BtIO setting the default
> > security level to MEDIUM.
> 
> Exactly, so if you really want to use kernel default you will have to
> change all of those, but I don't thing we use any other security level
> more than medium, then it would better not to change it.

The problem is that the same function is used within btio.c for parsing
options, no matter if they're from _set, _connect or _listen. Having an
default to MEDIUM within btio.c means that we don't know when a
bt_io_set caller *doesn't* want to modify the existing security level.
(something the commit message should explain more clearly, btw). So I do
think we need to remove this default from btio.c and have all users set
it explicitly when needed (I could find 2 or 3 places missing it under
audio/ but there could be more). A simple "git grep BT_IO_OPT_" gives a
pretty good overview. Just look for places that give a PSM or RFCOMM
channel but no SEC_LEVEL.

Johan