[libvirt] [PATCH 1/9] Fix crash when aborting a stream from a I/O callback

[Daniel P. Berrange]

On Tue, Jun 28, 2011 at 11:39:41AM -0600, Eric Blake wrote:
> On 06/28/2011 11:01 AM, Daniel P. Berrange wrote:
> > If a callback being invoked from a stream issues a virStreamAbort
> > operation, the stream data will be free'd but the callback will
> > then stil try to use this. Delay free'ing of the stream data when
> 
> s/stil/still/
> 
> > a callback is dispatching
> > 
> > * src/fdstream.c: Delay stream free when callback is active
> > ---
> >  src/fdstream.c |   33 +++++++++++++++++++++++----------
> >  1 files changed, 23 insertions(+), 10 deletions(-)
> > 
> 
> >      cb(stream, events, cbopaque);
> >  
> >      virMutexLock(&fdst->lock);
> > -    fdst->dispatching = 0;
> > +    fdst->dispatching = false;
> >      if (fdst->cbRemoved && ff)
> >          (ff)(cbopaque);
> 
> cb is called without locks, while ff is still under the lock.  No change
> from previous status quo, but I wonder if ff should ever be moved
> outside the lock.

For the way the free callback is used, I dont think it matters

Daniel
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