af-packet: fix oops when socket is not present
Due to a NULL dereference, the following patch is causing oops
in normal trafic condition:
commit c0de08d04215031d68fa13af36f347a6cfa252ca
Author: Eric Leblond <eric@regit.org>
Date: Thu Aug 16 22:02:58 2012 +0000
af_packet: don't emit packet on orig fanout group
This buggy patch was a feature fix and has reached most stable
branches.
When skb->sk is NULL and when packet fanout is used, there is a
crash in match_fanout_group where skb->sk is accessed.
This patch fixes the issue by returning false as soon as the
socket is NULL: this correspond to the wanted behavior because
the kernel as to resend the skb to all the listening socket in
this case.
Signed-off-by: Eric Leblond <eric@regit.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index 09cb3f6..bda6d00 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1666,7 +1666,7 @@
static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
{
- if (ptype->af_packet_priv == NULL)
+ if (!ptype->af_packet_priv || !skb->sk)
return false;
if (ptype->id_match)