Messages in this thread Patch in this message |  | | From | Jason Wang <> | Subject | [PATCH net] net: flow_dissector: fail on evil iph->ihl | Date | Fri, 1 Nov 2013 15:01:10 +0800 |
| |
We don't validate iph->ihl which may lead a dead loop if we meet a IPIP skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl is evil (less than 5).
This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae (rps: support IPIP encapsulation).
Cc: Eric Dumazet <edumazet@google.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> --- This patch is needed for stable. --- net/core/flow_dissector.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 8d7d0dd..143b6fd 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -40,7 +40,7 @@ again: struct iphdr _iph; ip: iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); - if (!iph) + if (!iph || iph->ihl < 5) return false; if (ip_is_fragment(iph)) -- 1.8.1.2
|  |