On Mon, Sep 13, 2021 at 07:41:08AM +0200, Christoph Hellwig wrote:

Hi all,

Al pointed out multiple times that seq_get_buf is highly dangerous as
it opens up the tight seq_file abstractions to buffer overflows.  The
last such caller now is sysfs.

This series allows attributes to implement a seq_show method and switch
the block and XFS code as users that I'm most familiar with to use
seq_files directly after a few preparatory cleanups.  With this series
"leaf" users of sysfs_ops can be converted one at at a time, after that
we can move the seq_get_buf into the multiplexers (e.g. kobj, device,
class attributes) and remove the show method in sysfs_ops and repeat the
process until all attributes are converted.  This will probably take a
fair amount of time.

The whole series looks good to me. With Greg's sysfs_emit argument aside on
which I don't have any opinion,

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun