Re: [PATCH mptcp-next] mptcp: return 0 instead of 'err' var

[Mat Martineau <mathew.j.martineau@linux.intel.com>]

On Mon, 5 Dec 2022, Matthieu Baerts wrote:

> When 'err' is 0, it looks clearer to return '0' instead of the variable
> called 'err'.
>
> The behaviour is then not modified, just a clearer code.
>
> By doing this, we can also avoid false positive smatch warnings like
> this one:
>
>  net/mptcp/pm_netlink.c:1169 mptcp_pm_parse_pm_addr_attr() warn: missing error code? 'err'
>
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <error27@gmail.com>
> Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>

Thanks for the cleanup Matthieu. Looks good to me.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>


> ---
> net/mptcp/pm_netlink.c | 4 ++--
> net/mptcp/sockopt.c    | 2 +-
> 2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
> index 39b0f054f39f..d20f1d969900 100644
> --- a/net/mptcp/pm_netlink.c
> +++ b/net/mptcp/pm_netlink.c
> @@ -1187,7 +1187,7 @@ static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[],
>
> 	if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) {
> 		if (!require_family)
> -			return err;
> +			return 0;
>
> 		NL_SET_ERR_MSG_ATTR(info->extack, attr,
> 				    "missing family");
> @@ -1221,7 +1221,7 @@ static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[],
> 	if (tb[MPTCP_PM_ADDR_ATTR_PORT])
> 		addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT]));
>
> -	return err;
> +	return 0;
> }
>
> int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
> diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
> index a47423ebb33a..d4b1e6ec1b36 100644
> --- a/net/mptcp/sockopt.c
> +++ b/net/mptcp/sockopt.c
> @@ -740,7 +740,7 @@ static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname,
> 	}
> 	release_sock(sk);
>
> -	return err;
> +	return 0;
> }
>
> static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname,
>
> base-commit: 9324c815f96dd77d23679e999edb875d9f4acd34
> -- 
> 2.37.2
>
>

--
Mat Martineau
Intel