Re: [PATCH] bonding: fix crash when no slave devices

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 2/23/2016 12:13 PM, Bernard Iremonger wrote:
> If a bonded device is created when there are no slave devices
> there is loop in bond_ethdev_promiscous_enable() which results
> in a segmentation fault.
> I have applied a similar fix to bond_ethdev_promiscous_disable()
> where a similar loop could occur.
> 
> Fixes: 2efb58cbab6e ("bond: new link bonding library")
> Signed-off-by: Bernard Iremonger <bernard.iremonger@intel.com>
> ---
>  drivers/net/bonding/rte_eth_bond_pmd.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/bonding/rte_eth_bond_pmd.c b/drivers/net/bonding/rte_eth_bond_pmd.c
> index b63c886..78972fc 100644
> --- a/drivers/net/bonding/rte_eth_bond_pmd.c
> +++ b/drivers/net/bonding/rte_eth_bond_pmd.c
> @@ -1870,7 +1870,8 @@ bond_ethdev_promiscuous_enable(struct rte_eth_dev *eth_dev)
>  	case BONDING_MODE_TLB:
>  	case BONDING_MODE_ALB:
>  	default:
> -		rte_eth_promiscuous_enable(internals->current_primary_port);
> +		if (internals->slave_count > 0)
> +			rte_eth_promiscuous_enable(internals->current_primary_port);
>  	}
>  }
>  
> @@ -1898,7 +1899,8 @@ bond_ethdev_promiscuous_disable(struct rte_eth_dev *dev)
>  	case BONDING_MODE_TLB:
>  	case BONDING_MODE_ALB:
>  	default:
> -		rte_eth_promiscuous_disable(internals->current_primary_port);
> +		if (internals->slave_count > 0)
> +			rte_eth_promiscuous_disable(internals->current_primary_port);
>  	}
>  }
>  
> 
Hi Bernard,

The reason of this crash is when there is no slave, the value of
current_primary_port is 0, which is valid port_id, is this correct?

Does it make sense, instead of slave_count check, to make default
current_primary_port value a non valid port_id, like -1, so
is_valid_port() check catches it to prevents crash? For this and any
other cases.

Thanks,
ferruh