diff options
| author | Florian Westphal <fw@strlen.de> | 2017-04-14 20:22:43 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-04-17 15:09:23 -0400 |
| commit | 0aa8c13eb512823bc4d60397d666a6b6260bb965 (patch) | |
| tree | cb0a1a2dd8d48965f34613646c4d5b3a52c59e03 /net | |
| parent | 71947f0f91ad9c995e11c671d24bd4da5d11c0cb (diff) | |
| download | linux-0aa8c13eb512823bc4d60397d666a6b6260bb965.tar.gz | |
ipv6: drop non loopback packets claiming to originate from ::1
We lack a saddr check for ::1. This causes security issues e.g. with acls permitting connections from ::1 because of assumption that these originate from local machine. Assuming a source address of ::1 is local seems reasonable. RFC4291 doesn't allow such a source address either, so drop such packets. Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/ip6_input.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index aacfb4bce153..c45b12b4431c 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -122,11 +122,14 @@ int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); /* * RFC4291 2.5.3 + * The loopback address must not be used as the source address in IPv6 + * packets that are sent outside of a single node. [..] * A packet received on an interface with a destination address * of loopback must be dropped. */ - if (!(dev->flags & IFF_LOOPBACK) && - ipv6_addr_loopback(&hdr->daddr)) + if ((ipv6_addr_loopback(&hdr->saddr) || + ipv6_addr_loopback(&hdr->daddr)) && + !(dev->flags & IFF_LOOPBACK)) goto err; /* RFC4291 Errata ID: 3480 |