Re: [PATCH net-next v6 1/6] neighbour: Add hlist_node to struct neighbour

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Gilad Naaman <gnaaman@drivenets.com>
Date: Mon, 21 Oct 2024 19:36:22 +0000
> > > @@ -530,27 +532,47 @@ static void neigh_get_hash_rnd(u32 *x)
> > >  
> > >  static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
> > >  {
> > > +	size_t hash_heads_size = (1 << shift) * sizeof(struct hlist_head);
> > >  	size_t size = (1 << shift) * sizeof(struct neighbour *);
> > > -	struct neigh_hash_table *ret;
> > >  	struct neighbour __rcu **buckets;
> > > +	struct hlist_head *hash_heads;
> > > +	struct neigh_hash_table *ret;
> > >  	int i;
> > >  
> > > +	hash_heads = NULL;
> > 
> > nit: This init is not needed.
> 
> This is needed in order to prevent unitialized memory access if we failed to
> allocate `buckets`.

Ah, you are right.

> 
> If possible I'd prefer to leave this as-is, given that this is rewritten later,
> in commit 5.

Sounds good.  Let's remove that in patch 5.