ethtool: Validate master slave configuration before rtnl_lock()

Create a new function for input validations to be called before
rtnl_lock() and move the master slave validation to that function.

This would be a cleanup for next patch that would add another validation
to the new function.

Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ethtool/linkmodes.c b/net/ethtool/linkmodes.c
index c5bcb9a..bb8a335 100644 (file)
--- a/net/ethtool/linkmodes.c
+++ b/net/ethtool/linkmodes.c
@@ -325,6 +325,21 @@ static bool ethnl_validate_master_slave_cfg(u8 cfg)
        return false;
 }
 
+static int ethnl_check_linkmodes(struct genl_info *info, struct nlattr **tb)
+{
+       const struct nlattr *master_slave_cfg;
+
+       master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
+       if (master_slave_cfg &&
+           !ethnl_validate_master_slave_cfg(nla_get_u8(master_slave_cfg))) {
+               NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
+                                   "master/slave value is invalid");
+               return -EOPNOTSUPP;
+       }
+
+       return 0;
+}
+
 static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb,
                                  struct ethtool_link_ksettings *ksettings,
                                  bool *mod)
@@ -336,19 +351,11 @@ static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb,
 
        master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
        if (master_slave_cfg) {
-               u8 cfg = nla_get_u8(master_slave_cfg);
-
                if (lsettings->master_slave_cfg == MASTER_SLAVE_CFG_UNSUPPORTED) {
                        NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
                                            "master/slave configuration not supported by device");
                        return -EOPNOTSUPP;
                }
-
-               if (!ethnl_validate_master_slave_cfg(cfg)) {
-                       NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
-                                           "master/slave value is invalid");
-                       return -EOPNOTSUPP;
-               }
        }
 
        *mod = false;
@@ -386,6 +393,10 @@ int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info)
        bool mod = false;
        int ret;
 
+       ret = ethnl_check_linkmodes(info, tb);
+       if (ret < 0)
+               return ret;
+
        ret = ethnl_parse_header_dev_get(&req_info,
                                         tb[ETHTOOL_A_LINKMODES_HEADER],
                                         genl_info_net(info), info->extack,