[NETFILTER]: nf_conntrack_sip: flush expectations on call termination

Flush the RTP expectations we've created when a call is hung up or
terminated otherwise.

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

1 files changed, 48 insertions, 4 deletions

diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
index 71f744ad7653..8e7e5b465ffb 100644
--- a/net/netfilter/nf_conntrack_sip.c
+++ b/net/netfilter/nf_conntrack_sip.c
@@ -17,6 +17,7 @@
 #include <linux/netfilter.h>
 
 #include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_core.h>
 #include <net/netfilter/nf_conntrack_expect.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <linux/netfilter/nf_conntrack_sip.h>
@@ -533,6 +534,22 @@ int ct_sip_get_sdp_header(const struct nf_conn *ct, const char *dptr,
 }
 EXPORT_SYMBOL_GPL(ct_sip_get_sdp_header);
 
+static void flush_expectations(struct nf_conn *ct)
+{
+        struct nf_conn_help *help = nfct_help(ct);
+        struct nf_conntrack_expect *exp;
+        struct hlist_node *n, *next;
+
+        spin_lock_bh(&nf_conntrack_lock);
+        hlist_for_each_entry_safe(exp, n, next, &help->expectations, lnode) {
+                if (!del_timer(&exp->timeout))
+                        continue;
+                nf_ct_unlink_expect(exp);
+                nf_ct_expect_put(exp);
+        }
+        spin_unlock_bh(&nf_conntrack_lock);
+}
+
 static int set_expected_rtp(struct sk_buff *skb,
                             const char **dptr, unsigned int *datalen,
                             union nf_inet_addr *addr, __be16 port)
@@ -606,32 +623,58 @@ static int process_invite_response(struct sk_buff *skb,
                                    const char **dptr, unsigned int *datalen,
                                    unsigned int cseq, unsigned int code)
 {
+        enum ip_conntrack_info ctinfo;
+        struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
+
         if ((code >= 100 && code <= 199) ||
             (code >= 200 && code <= 299))
                 return process_sdp(skb, dptr, datalen, cseq);
-
-        return NF_ACCEPT;
+        else {
+                flush_expectations(ct);
+                return NF_ACCEPT;
+        }
 }
 
 static int process_update_response(struct sk_buff *skb,
                                    const char **dptr, unsigned int *datalen,
                                    unsigned int cseq, unsigned int code)
 {
+        enum ip_conntrack_info ctinfo;
+        struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
+
         if ((code >= 100 && code <= 199) ||
             (code >= 200 && code <= 299))
                 return process_sdp(skb, dptr, datalen, cseq);
-
-        return NF_ACCEPT;
+        else {
+                flush_expectations(ct);
+                return NF_ACCEPT;
+        }
 }
 
 static int process_prack_response(struct sk_buff *skb,
                                   const char **dptr, unsigned int *datalen,
                                   unsigned int cseq, unsigned int code)
 {
+        enum ip_conntrack_info ctinfo;
+        struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
+
         if ((code >= 100 && code <= 199) ||
             (code >= 200 && code <= 299))
                 return process_sdp(skb, dptr, datalen, cseq);
+        else {
+                flush_expectations(ct);
+                return NF_ACCEPT;
+        }
+}
+
+static int process_bye_request(struct sk_buff *skb,
+                               const char **dptr, unsigned int *datalen,
+                               unsigned int cseq)
+{
+        enum ip_conntrack_info ctinfo;
+        struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 
+        flush_expectations(ct);
         return NF_ACCEPT;
 }
 
@@ -640,6 +683,7 @@ static const struct sip_handler sip_handlers[] = {
         SIP_HANDLER("UPDATE", process_sdp, process_update_response),
         SIP_HANDLER("ACK", process_sdp, NULL),
         SIP_HANDLER("PRACK", process_sdp, process_prack_response),
+        SIP_HANDLER("BYE", process_bye_request, NULL),
 };
 
 static int process_sip_response(struct sk_buff *skb,