[PATCH 8/9] xfs: catch bad block numbers freeing extents.

Dave Chinner david at fromorbit.com
Wed Apr 6 19:18:22 CDT 2011


On Wed, Apr 06, 2011 at 09:59:51AM -0400, Christoph Hellwig wrote:
> > +	/* validate the extent size is legal now we have the agf locked */
> > +	if (!args.agbp) {
> > +		error = EFSCORRUPTED;
> > +		goto error0;
> > +	}
> 
> This is not a corruption case, but would require someone changing
> xfs_fix_freelist and messing up.  I think the check can be removed
> given that the potentially added bug would trivially trip up as
> a NULL pointer dereference.

Well, I figured the only way we wouldn't get the agbp is if it was
corrupted somehow (e.g. it gets re-read from disk), but that should
return an error from xfs_alloc_fix_freelist() anyway. So i think you
are right - the check can be dropped.

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com




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