netfilter: log: netns NULL ptr bug when calling from conntrack

Since (69b34fb netfilter: xt_LOG: add net namespace support
for xt_LOG), we hit this:

[ 4224.708977] BUG: unable to handle kernel NULL pointer dereference at 0000000000000388
[ 4224.709074] IP: [<ffffffff8147f699>] ipt_log_packet+0x29/0x270

when callling log functions from conntrack both in and out
are NULL i.e. the net pointer is invalid.

Adding struct net *net in call to nf_logfn() will secure that
there always is a vaild net ptr.

Reported as netfilter's bugzilla bug 818:
https://bugzilla.netfilter.org/show_bug.cgi?id=818

Reported-by: Ronald <ronald645@gmail.com>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 4 insertions, 2 deletions

diff --git a/include/net/netfilter/nf_log.h b/include/net/netfilter/nf_log.h
index 31f1fb9eb784..99eac12d040b 100644
--- a/include/net/netfilter/nf_log.h
+++ b/include/net/netfilter/nf_log.h
@@ -30,7 +30,8 @@ struct nf_loginfo {
         } u;
 };
 
-typedef void nf_logfn(u_int8_t pf,
+typedef void nf_logfn(struct net *net,
+                      u_int8_t pf,
                       unsigned int hooknum,
                       const struct sk_buff *skb,
                       const struct net_device *in,
diff --git a/include/net/netfilter/nfnetlink_log.h b/include/net/netfilter/nfnetlink_log.h
index e2dec42c2db2..5ca3f14f0998 100644
--- a/include/net/netfilter/nfnetlink_log.h
+++ b/include/net/netfilter/nfnetlink_log.h
@@ -2,7 +2,8 @@
 #define _KER_NFNETLINK_LOG_H
 
 void
-nfulnl_log_packet(u_int8_t pf,
+nfulnl_log_packet(struct net *net,
+                  u_int8_t pf,
                   unsigned int hooknum,
                   const struct sk_buff *skb,
                   const struct net_device *in,