diff options
author | David Ahern <dsahern@gmail.com> | 2018-10-07 20:16:43 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-10-08 10:39:05 -0700 |
commit | 8dfbda19a21b30475b7e6dcf2141a98ed2a19af5 (patch) | |
tree | 534fb338375a56f3dfeb3066a6e7f85c3017866e /net/core/rtnetlink.c | |
parent | c77b93641e7dc88ef4919d8126949e3ec3ffe407 (diff) |
rtnetlink: Move input checking for rtnl_fdb_dump to helper
Move the existing input checking for rtnl_fdb_dump into a helper,
valid_fdb_dump_legacy. This function will retain the current
logic that works around the 2 headers that userspace has been
allowed to send up to this point.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/rtnetlink.c')
-rw-r--r-- | net/core/rtnetlink.c | 53 |
1 files changed, 33 insertions, 20 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index f6d2609cfa9f..c7509c789fb6 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3799,22 +3799,13 @@ out: } EXPORT_SYMBOL(ndo_dflt_fdb_dump); -static int rtnl_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb) +static int valid_fdb_dump_legacy(const struct nlmsghdr *nlh, + int *br_idx, int *brport_idx, + struct netlink_ext_ack *extack) { - struct net_device *dev; + struct ifinfomsg *ifm = nlmsg_data(nlh); struct nlattr *tb[IFLA_MAX+1]; - struct net_device *br_dev = NULL; - const struct net_device_ops *ops = NULL; - const struct net_device_ops *cops = NULL; - struct ifinfomsg *ifm = nlmsg_data(cb->nlh); - struct net *net = sock_net(skb->sk); - struct hlist_head *head; - int brport_idx = 0; - int br_idx = 0; - int h, s_h; - int idx = 0, s_idx; - int err = 0; - int fidx = 0; + int err; /* A hack to preserve kernel<->userspace interface. * Before Linux v4.12 this code accepted ndmsg since iproute2 v3.3.0. @@ -3823,20 +3814,42 @@ static int rtnl_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb) * Fortunately these sizes don't conflict with the size of ifinfomsg * with an optional attribute. */ - if (nlmsg_len(cb->nlh) != sizeof(struct ndmsg) && - (nlmsg_len(cb->nlh) != sizeof(struct ndmsg) + + if (nlmsg_len(nlh) != sizeof(struct ndmsg) && + (nlmsg_len(nlh) != sizeof(struct ndmsg) + nla_attr_size(sizeof(u32)))) { - err = nlmsg_parse(cb->nlh, sizeof(struct ifinfomsg), tb, - IFLA_MAX, ifla_policy, cb->extack); + err = nlmsg_parse(nlh, sizeof(struct ifinfomsg), tb, IFLA_MAX, + ifla_policy, extack); if (err < 0) { return -EINVAL; } else if (err == 0) { if (tb[IFLA_MASTER]) - br_idx = nla_get_u32(tb[IFLA_MASTER]); + *br_idx = nla_get_u32(tb[IFLA_MASTER]); } - brport_idx = ifm->ifi_index; + *brport_idx = ifm->ifi_index; } + return 0; +} + +static int rtnl_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct net_device *dev; + struct net_device *br_dev = NULL; + const struct net_device_ops *ops = NULL; + const struct net_device_ops *cops = NULL; + struct net *net = sock_net(skb->sk); + struct hlist_head *head; + int brport_idx = 0; + int br_idx = 0; + int h, s_h; + int idx = 0, s_idx; + int err = 0; + int fidx = 0; + + err = valid_fdb_dump_legacy(cb->nlh, &br_idx, &brport_idx, + cb->extack); + if (err < 0) + return err; if (br_idx) { br_dev = __dev_get_by_index(net, br_idx); |