Re: [PATCH] cfg80211: hold reg_mutex when updating regulatory

[Sven Neumann <s.neumann@raumfeld.com>]

Hi,

On Fri, 2011-07-15 at 13:32 -0400, John W. Linville wrote:
> Luis, any comment on this?
> 
> On Tue, Jul 12, 2011 at 09:52:39AM +0200, Sven Neumann wrote:
> > The function wiphy_update_regulatory() uses the static variable
> > last_request and thus needs to be called with reg_mutex held.
> > This is the case for all users in reg.c, but the function was
> > exported for use by wiphy_register(), from where it is called
> > without the lock being held.
> > 
> > Fix this by making wiphy_update_regulatory() private and introducing
> > regulatory_update() as a wrapper that acquires and holds the lock.
> > 
> > Signed-off-by: Sven Neumann <s.neumann@raumfeld.com>

I'd appreciate if someone would review this patch. But probably this is
not really an issue except that it's somewhat ugly to export a function
that should be called with a lock held and that lock is actually
private. But in this particular case it is not a problem, as far as I
can see, since the only user of wiphy_update_regulatory() outside
net/wireless/reg.c is initialization code. So there is not likely going
to be a race condition here.


Sven