udp: prevent bugcheck if filter truncates packet too much
If socket filter truncates an udp packet below the length of UDP header in udpv6_queue_rcv_skb() or udp_queue_rcv_skb(), it will trigger a BUG_ON in skb_pull_rcsum(). This BUG_ON (and therefore a system crash if kernel is configured that way) can be easily enforced by an unprivileged user which was reported as CVE-2016-6162. For a reproducer, see http://seclists.org/oss-sec/2016/q3/8 Fixes: e6afc8ac ("udp: remove headers from UDP packets before queueing") Reported-by:Marco Grassi <marco.gra@gmail.com> Signed-off-by:
Michal Kubecek <mkubecek@suse.cz> Acked-by:
Eric Dumazet <edumazet@google.com> Acked-by:
Willem de Bruijn <willemb@google.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
Showing
Please register or sign in to comment