Re: [PATCH] xfs: fix NULL ptr in xfs_attr_leaf_get

[Christoph Hellwig <hch@infradead.org>]

On Tue, Jan 06, 2026 at 07:40:26AM -0800, Darrick J. Wong wrote:
> > > Fixes v5.8-rc4-95-g07120f1abdff ("xfs: Add xfs_has_attr and subroutines")
> > > No reproducer.
> > 
> > Eww, what a mess.  I think we're better off to always leave releasing
> > bp to the caller.  Something like the patch below.  Only compile tested
> > for now, but I'll kick off an xfstests run.
> > 
> > Or maybe we might just kill off xfs_attr_leaf_hasname entirely and open
> > code it in the three callers, which might end up being more readable?
> 
> ...unless this is yet another case of the block layer returning ENODATA,
> which is then mistaken for returning ENOATTR-but-here's-your-buffer by
> the xfs_attr code?

Not really and unless.  This patch (and the full removal that I've
prepared in the meantime) still fix the missing buffer release in that
case and make the code easier to follow.  But yes, they would not fix
the underlying issue, which is why I still think we should not blindly
propagate block layer errors into b_error.