Re: [PATCH] mlxsw: core_env: Fix stack info leak in mlxsw_env_linecard_modules_power_mode_apply

[Ido Schimmel <idosch@nvidia.com>]

On Sat, Aug 30, 2025 at 04:11:22PM +0800, Miaoqian Lin wrote:
> The extack was declared on the stack without initialization.
> If mlxsw_env_set_module_power_mode_apply() fails to set extack,
> accessing extack._msg could leak information.

Unless I'm missing something, I don't see a case where
mlxsw_env_set_module_power_mode_apply() returns an error without setting
extack. IOW, I don't see how this info leak can happen with existing
code.

> 
> Fixes: 06a0fc43bb10 ("mlxsw: core_env: Add interfaces for line card initialization and de-initialization")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>  drivers/net/ethernet/mellanox/mlxsw/core_env.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_env.c b/drivers/net/ethernet/mellanox/mlxsw/core_env.c
> index 294e758f1067..38941c1c35d3 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/core_env.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/core_env.c
> @@ -1332,7 +1332,7 @@ mlxsw_env_linecard_modules_power_mode_apply(struct mlxsw_core *mlxsw_core,
>  	for (i = 0; i < env->line_cards[slot_index]->module_count; i++) {
>  		enum ethtool_module_power_mode_policy policy;
>  		struct mlxsw_env_module_info *module_info;
> -		struct netlink_ext_ack extack;
> +		struct netlink_ext_ack extack = {};
>  		int err;
>  
>  		module_info = &env->line_cards[slot_index]->module_info[i];
> -- 
> 2.39.5 (Apple Git-154)
>