Re: [PATCH] bcachefs: Fix NULL ptr dereference in btree_node_iter_and_journal_peek

[Kent Overstreet]

On Wed, Oct 23, 2024 at 03:33:22PM +0800, Alan Huang wrote:
> On Oct 23, 2024, at 15:21, Piotr Zalewski <pZ010001011111@xxxxxxxxx> wrote:
> > 
> > Add NULL check for key returned from bch2_btree_and_journal_iter_peek in
> > btree_node_iter_and_journal_peek to avoid NULL ptr dereference in
> > bch2_bkey_buf_reassemble.
> 
> It would be helpful if the commit message explained why k.k is null in this case

This code is only for iterating over interior btree nodes - k.k is only
null when we have a bad btree topology (gaps).

Piotr, could you add a comment to that effect?