Re: [net-next 01/10] devlink: Fix param set handling for string type

[Jakub Kicinski <jakub.kicinski@netronome.com>]

On Wed,  1 Aug 2018 14:52:46 -0700, Saeed Mahameed wrote:
> From: Moshe Shemesh <moshe@mellanox.com>
> 
> In case devlink param type is string, it needs to copy the string value
> it got from the input to devlink_param_value.
> 
> Fixes: e3b7ca18ad7b ("devlink: Add param set command")
> Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
> Acked-by: Jiri Pirko <jiri@mellanox.com>
> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
> ---
>  include/net/devlink.h | 2 +-
>  net/core/devlink.c    | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/include/net/devlink.h b/include/net/devlink.h
> index b9b89d6604d4..b0e17c025fdc 100644
> --- a/include/net/devlink.h
> +++ b/include/net/devlink.h
> @@ -311,7 +311,7 @@ union devlink_param_value {
>  	u8 vu8;
>  	u16 vu16;
>  	u32 vu32;
> -	const char *vstr;
> +	char vstr[DEVLINK_PARAM_MAX_STRING_VALUE];
>  	bool vbool;
>  };
>  
> diff --git a/net/core/devlink.c b/net/core/devlink.c
> index 65fc366a78a4..61e126c28526 100644
> --- a/net/core/devlink.c
> +++ b/net/core/devlink.c
> @@ -3014,7 +3014,8 @@ devlink_param_value_get_from_info(const struct devlink_param *param,
>  		if (nla_len(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]) >
>  		    DEVLINK_PARAM_MAX_STRING_VALUE)
>  			return -EINVAL;
> -		value->vstr = nla_data(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
> +		strcpy(value->vstr,
> +		       nla_data(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]));

DEVLINK_ATTR_PARAM_VALUE_DATA is a type mux, I'm struggling to find in
the code where it's checked for being null-terminated for strings.

>  		break;
>  	case DEVLINK_PARAM_TYPE_BOOL:
>  		value->vbool = info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA] ?