rtnetlink: Update fib dumps for strict data checking
Add helper to check netlink message for route dumps. If the strict flag
is set the dump request is expected to have an rtmsg struct as the header.
All elements of the struct are expected to be 0 with the exception of
rtm_flags (which is used by both ipv4 and ipv6 dumps) and no attributes
can be appended. rtm_flags can only have RTM_F_CLONED and RTM_F_PREFIX
set.
Update inet_dump_fib, inet6_dump_fib, mpls_dump_routes, ipmr_rtm_dumproute,
and ip6mr_rtm_dumproute to call this helper if strict data checking is
enabled.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index cf709ea..e14d244 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -564,6 +564,7 @@ static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,
static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
{
+ const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
unsigned int h, s_h;
unsigned int e = 0, s_e;
@@ -573,6 +574,13 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
struct hlist_head *head;
int res = 0;
+ if (cb->strict_check) {
+ int err = ip_valid_fib_dump_req(nlh, cb->extack);
+
+ if (err < 0)
+ return err;
+ }
+
s_h = cb->args[0];
s_e = cb->args[1];