cvs commit: src/sys/dev/fxp if_fxp.c

[Kris Kennaway]

On Wed, Mar 16, 2005 at 07:40:56PM +0100, Maxime Henrion wrote:
> Kris Kennaway wrote:
> > On Wed, Mar 16, 2005 at 04:39:04PM +0000, Maxime Henrion wrote:
> > > mux         2005-03-16 16:39:04 UTC
> > > 
> > >   FreeBSD src repository
> > > 
> > >   Modified files:
> > >     sys/dev/fxp          if_fxp.c 
> > >   Log:
> > >   Unload and destroy the TX DMA maps before destroying the DMA tag
> > >   they're attached to, not after.
> > >   
> > >   Spotted by:     Coverity via sam
> > 
> > Is this likely to have caused panics at runtime?  A few people
> > (including me) have seen dma-related or use-after-free panics from
> > fxp.
> 
> This won't fix any use-after-free panics at runtime, since the faulty
> code is in fxp_release() which will only get called from fxp_attach() in
> error scenarios and from fxp_detach().
> 
> I've never seen reports about use-after-free from fxp(4), I'd like to
> know about those, even if the odds of those not being false positives is
> small...

I think I mailed current about it a few months ago (but can't access
my email archive until the weekend), and a few other people have
reported similar-looking panics too.  I've only seen it 2-3 times in
total.

Kris

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