Re: [PATCH net v3] team: fix null-ptr-deref when team device type is changed

[Hangbin Liu <liuhangbin@gmail.com>]

On Tue, Sep 05, 2023 at 04:10:56PM +0800, Ziyang Xuan wrote:
> ---
>  drivers/net/team/team.c | 5 ++++-
>  net/ethernet/eth.c      | 1 +
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
> index d3dc22509ea5..12fb5f4cff06 100644
> --- a/drivers/net/team/team.c
> +++ b/drivers/net/team/team.c
> @@ -2127,7 +2127,10 @@ static const struct ethtool_ops team_ethtool_ops = {
>  static void team_setup_by_port(struct net_device *dev,
>  			       struct net_device *port_dev)
>  {
> -	dev->header_ops	= port_dev->header_ops;
> +	if (port_dev->type == ARPHRD_ETHER)
> +		dev->header_ops	= &eth_header_ops;
> +	else
> +		dev->header_ops	= port_dev->header_ops;
>  	dev->type = port_dev->type;
>  	dev->hard_header_len = port_dev->hard_header_len;
>  	dev->needed_headroom = port_dev->needed_headroom;
> diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
> index 2edc8b796a4e..157833509adb 100644
> --- a/net/ethernet/eth.c
> +++ b/net/ethernet/eth.c
> @@ -347,6 +347,7 @@ const struct header_ops eth_header_ops ____cacheline_aligned = {
>  	.cache_update	= eth_header_cache_update,
>  	.parse_protocol	= eth_header_parse_protocol,
>  };
> +EXPORT_SYMBOL(eth_header_ops);
>  
>  /**
>   * ether_setup - setup Ethernet network device
> -- 
> 2.25.1
> 

Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>