| Message ID | 1448886887-17104-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index e6bd6df9e2a2..1f618bbce0ac 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1412,10 +1412,10 @@ static void __fanout_unlink(struct sock *sk, struct packet_sock *po) static bool match_fanout_group(struct packet_type *ptype, struct sock *sk) { - if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout) - return true; + if (sk->sk_family != PF_PACKET) + return false; - return false; + return ptype->af_packet_priv == pkt_sk(sk)->fanout; } static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
This is a note to let you know that I have just added a patch titled packet: fix match_fanout_group() to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt21. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From a0052d221e5ba1ee05221cbf5dc2280eb3d82a14 Mon Sep 17 00:00:00 2001 From: Eric Dumazet <edumazet@google.com> Date: Fri, 9 Oct 2015 11:29:32 -0700 Subject: packet: fix match_fanout_group() commit 161642e24fee40fba2c5bc2ceacc00d118a22d65 upstream. Recent TCP listener patches exposed a prior af_packet bug : match_fanout_group() blindly assumes it is always safe to cast sk to a packet socket to compare fanout with af_packet_priv But SYNACK packets can be sent while attached to request_sock, which are smaller than a "struct sock". We can read non existent memory and crash. Fixes: c0de08d04215 ("af_packet: don't emit packet on orig fanout group") Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Eric Leblond <eric@regit.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- net/packet/af_packet.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)