Fix reference leaks involving SIP Replaces transfers

The reference held for SIP blind transfers using the Replaces header in an
INVITE was never freed on success and also failed to be freed in some error
conditions.  This caused a file descriptor leak since the RTP structures in use
at the time of the transfer were never freed.  This reference leak and another
relating to subscriptions in the same code path have now been corrected.

(Closes issue ASTERISK-19579)
Reported by: Maciej Krajewski
Tested by: Maciej Karjewski
........

Merged revisions 363986 from http://svn.asterisk.org/svn/asterisk/branches/1.8

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@363987 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 46fc831faf63db2140558c61ec7db2265d7aa9dc..27ee0752123eb3ece4135059e2b6736cc6d5ef3f 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -5841,8 +5841,12 @@ void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist)
        }
        if (p->udptl)
                ast_udptl_destroy(p->udptl);
-       if (p->refer)
+       if (p->refer) {
+               if (p->refer->refer_call) {
+                       p->refer->refer_call = dialog_unref(p->refer->refer_call, "unref dialog p->refer->refer_call");
+               }
                ast_free(p->refer);
+       }
        if (p->route) {
                free_old_route(p->route);
                p->route = NULL;
@@ -23096,6 +23100,7 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
                                if (subscription->owner) {
                                        ast_channel_unlock(subscription->owner);
                                }
+                               subscription = dialog_unref(subscription, "unref dialog subscription");
                        }
                }
 
@@ -23114,7 +23119,6 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 
                if (p->refer->refer_call == p) {
                        ast_log(LOG_NOTICE, "INVITE with replaces into it's own call id (%s == %s)!\n", replace_id, p->callid);
-                       p->refer->refer_call = dialog_unref(p->refer->refer_call, "unref dialog p->refer->refer_call");
                        transmit_response_reliable(p, "400 Bad request", req);  /* The best way to not not accept the transfer */
                        error = 1;
                }
@@ -23142,6 +23146,7 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
                                if (p->refer->refer_call->owner) {
                                        ast_channel_unlock(p->refer->refer_call->owner);
                                }
+                               p->refer->refer_call = dialog_unref(p->refer->refer_call, "unref dialog p->refer->refer_call");
                        }
                        refer_locked = 0;
                        p->invitestate = INV_COMPLETED;