[NETFILTER]: nf_conntrack_netbios_ns: fix uninitialized member in expectation

->helper is uninitialized in the expectation registered by the netbios_ns
helper and it later copied to the expected connection, which causes invalid
memory dereferences when trying to call the helper.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/net/netfilter/nf_conntrack_netbios_ns.c b/net/netfilter/nf_conntrack_netbios_ns.c
index a5b234e444dc..2a48efdf0d67 100644
--- a/net/netfilter/nf_conntrack_netbios_ns.c
+++ b/net/netfilter/nf_conntrack_netbios_ns.c
@@ -89,6 +89,7 @@ static int help(struct sk_buff **pskb, unsigned int protoff,
 
         exp->expectfn             = NULL;
         exp->flags                = NF_CT_EXPECT_PERMANENT;
+        exp->helper               = NULL;
 
         nf_conntrack_expect_related(exp);
         nf_conntrack_expect_put(exp);