diff options
-rw-r--r-- | include/linux/netdevice.h | 2 | ||||
-rw-r--r-- | net/core/dev.c | 29 | ||||
-rw-r--r-- | net/core/rtnetlink.c | 13 |
3 files changed, 32 insertions, 12 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 13f09706033a..f8fde9fa479c 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3666,6 +3666,8 @@ int dev_set_alias(struct net_device *, const char *, size_t); int dev_get_alias(const struct net_device *, char *, size_t); int dev_change_net_namespace(struct net_device *, struct net *, const char *); int __dev_set_mtu(struct net_device *, int); +int dev_validate_mtu(struct net_device *dev, int mtu, + struct netlink_ext_ack *extack); int dev_set_mtu_ext(struct net_device *dev, int mtu, struct netlink_ext_ack *extack); int dev_set_mtu(struct net_device *, int); diff --git a/net/core/dev.c b/net/core/dev.c index 3098c90d60e2..3a94ec2610ea 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7973,6 +7973,22 @@ int __dev_set_mtu(struct net_device *dev, int new_mtu) } EXPORT_SYMBOL(__dev_set_mtu); +int dev_validate_mtu(struct net_device *dev, int new_mtu, + struct netlink_ext_ack *extack) +{ + /* MTU must be positive, and in range */ + if (new_mtu < 0 || new_mtu < dev->min_mtu) { + NL_SET_ERR_MSG(extack, "mtu less than device minimum"); + return -EINVAL; + } + + if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { + NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); + return -EINVAL; + } + return 0; +} + /** * dev_set_mtu_ext - Change maximum transfer unit * @dev: device @@ -7989,16 +8005,9 @@ int dev_set_mtu_ext(struct net_device *dev, int new_mtu, if (new_mtu == dev->mtu) return 0; - /* MTU must be positive, and in range */ - if (new_mtu < 0 || new_mtu < dev->min_mtu) { - NL_SET_ERR_MSG(extack, "mtu less than device minimum"); - return -EINVAL; - } - - if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { - NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); - return -EINVAL; - } + err = dev_validate_mtu(dev, new_mtu, extack); + if (err) + return err; if (!netif_device_present(dev)) return -ENODEV; diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index e4ec575c1fba..944acb1a9f29 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2959,8 +2959,17 @@ struct net_device *rtnl_create_link(struct net *net, const char *ifname, dev->rtnl_link_ops = ops; dev->rtnl_link_state = RTNL_LINK_INITIALIZING; - if (tb[IFLA_MTU]) - dev->mtu = nla_get_u32(tb[IFLA_MTU]); + if (tb[IFLA_MTU]) { + u32 mtu = nla_get_u32(tb[IFLA_MTU]); + int err; + + err = dev_validate_mtu(dev, mtu, extack); + if (err) { + free_netdev(dev); + return ERR_PTR(err); + } + dev->mtu = mtu; + } if (tb[IFLA_ADDRESS]) { memcpy(dev->dev_addr, nla_data(tb[IFLA_ADDRESS]), nla_len(tb[IFLA_ADDRESS])); |