[NETFILTER]: Fix oops in conntrack event cache

ip_ct_refresh_acct() can be called without a valid "skb" pointer.
This used to work, since ct_add_counters() deals with that fact.
However, the recently-added event cache doesn't handle this at all.

This patch is a quick fix that is supposed to be replaced soon by a cleaner
solution during the pending redesign of the event cache.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 1 deletions

diff --git a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c
index 19cba16e6e1e..f8cd8e42961e 100644
--- a/net/ipv4/netfilter/ip_conntrack_core.c
+++ b/net/ipv4/netfilter/ip_conntrack_core.c
@@ -1143,7 +1143,10 @@ void ip_ct_refresh_acct(struct ip_conntrack *ct,
                 if (del_timer(&ct->timeout)) {
                         ct->timeout.expires = jiffies + extra_jiffies;
                         add_timer(&ct->timeout);
-                        ip_conntrack_event_cache(IPCT_REFRESH, skb);
+                        /* FIXME: We loose some REFRESH events if this function
+                         * is called without an skb.  I'll fix this later -HW */
+                        if (skb)
+                                ip_conntrack_event_cache(IPCT_REFRESH, skb);
                 }
                 ct_add_counters(ct, ctinfo, skb);
                 write_unlock_bh(&ip_conntrack_lock);