Re: [PATCH] net: bonding: fix error return code of bond_neigh_init()

[Roi Dayan]

On 2021-03-08 5:11 AM, Jia-Ju Bai wrote:
> When slave is NULL or slave_ops->ndo_neigh_setup is NULL, no error
> return code of bond_neigh_init() is assigned.
> To fix this bug, ret is assigned with -EINVAL in these cases.
>
> Fixes: 9e99bfefdbce ("bonding: fix bond_neigh_init()")
> Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
> ---
>   drivers/net/bonding/bond_main.c | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
> index 74cbbb22470b..456315bef3a8 100644
> --- a/drivers/net/bonding/bond_main.c
> +++ b/drivers/net/bonding/bond_main.c
> @@ -3978,11 +3978,15 @@ static int bond_neigh_init(struct neighbour *n)
>   
>   	rcu_read_lock();
>   	slave = bond_first_slave_rcu(bond);
> -	if (!slave)
> +	if (!slave) {
> +		ret = -EINVAL;
>   		goto out;
> +	}
>   	slave_ops = slave->dev->netdev_ops;
> -	if (!slave_ops->ndo_neigh_setup)
> +	if (!slave_ops->ndo_neigh_setup) {
> +		ret = -EINVAL;
>   		goto out;
> +	}
>   
>   	/* TODO: find another way [1] to implement this.
>   	 * Passing a zeroed structure is fragile,


Hi,

This breaks basic functionally that always worked. A slave doesn't need
to exists nor to implement ndo_neigh_setup.
Now trying to add a neigh entry because of that fails.
This commit needs to be reverted.

Thanks,
Roi