Re: [RFC] Bluetooth: Fix compile warning in l2cap_core.c

[Andrei Emeltchenko <andrei.emeltchenko.news@gmail.com>]

On Wed, Jun 06, 2012 at 01:38:59AM -0300, Gustavo Padovan wrote:
> Hi Andre,
> 
> * Andre Guedes <andre.guedes@openbossa.org> [2012-06-05 16:01:42 -0300]:
> 
> > Hi Gustavo,
> > 
> > On Mon, Jun 4, 2012 at 4:17 AM, Szymon Janc <szymon.janc@tieto.com> wrote:
> > > Hi,
> > >
> > >> * Andre Guedes <andre.guedes@openbossa.org> [2012-05-31 20:39:16 -0300]:
> > >>
> > >> > This patch fixes the following warning reported by gcc 4.7.0:
> > >> >
> > >> > net/bluetooth/l2cap_core.c: In function 'l2cap_config_rsp':
> > >> > net/bluetooth/l2cap_core.c:3302:13: warning: 'rfc.max_pdu_size' may be used uninitialized in this function [-Wmaybe-uninitialized]
> > >> > net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.max_pdu_size' was declared here
> > >> > net/bluetooth/l2cap_core.c:3298:25: warning: 'rfc.monitor_timeout' may be used uninitialized in this function [-Wmaybe-uninitialized]
> > >> > net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.monitor_timeout' was declared here
> > >> > net/bluetooth/l2cap_core.c:3297:25: warning: 'rfc.retrans_timeout' may be used uninitialized in this function [-Wmaybe-uninitialized]
> > >> > net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.retrans_timeout' was declared here
> > >> > net/bluetooth/l2cap_core.c:3295:2: warning: 'rfc.mode' may be used uninitialized in this function [-Wmaybe-uninitialized]
> > >> > net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.mode' was declared here
> > >>
> > >> So I think this is a false positive, I've seen this warning here for more than
> > >> a month, since I updated to fedora 17.
> > >> At some people will disable this warning in the kernel compile process if this
> > >> appear in others places in the kernel as false positive too.
> > >
> > > What if remote device misbehaves and sends bogus L2CAP_CONF_RFC i.e. with wrong length?
> > 
> > I'm not sure this is a false positive. If remote device misbehaves and
> > sends bogus L2CAP_CONF_RFC with wrong length (as Szymon said) we go to
> > "done" label and 'rfc' is used uninitialized.

what is not OK is that double conversion.

Best regards 
Andrei Emeltchenko