ipv6: fix crash on ICMPv6 redirects with prohibited/blackholed source

There are other error values besides ip6_null_entry that can be returned by
ip6_route_redirect(): fib6_rule_action() can also result in
ip6_blk_hole_entry and ip6_prohibit_entry if such ip rules are installed.

Only checking for ip6_null_entry in rt6_do_redirect() causes ip6_ins_rt()
to be called with rt->rt6i_table == NULL in these cases, making the kernel
crash.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Matthias Schiffer 2015-11-02 01:24:38 +01:00 committed by David S. Miller
parent 4ab42d78e3
commit ec13ad1d70

View File

@ -2099,7 +2099,6 @@ static int ip6_route_del(struct fib6_config *cfg)
static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
{
struct net *net = dev_net(skb->dev);
struct netevent_redirect netevent;
struct rt6_info *rt, *nrt = NULL;
struct ndisc_options ndopts;
@ -2160,7 +2159,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu
}
rt = (struct rt6_info *) dst;
if (rt == net->ipv6.ip6_null_entry) {
if (rt->rt6i_flags & RTF_REJECT) {
net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
return;
}