siprec: make timeout handling more robust

Make sure we are not trying to access the RTP context that has been
destroyed along with the dialog moving in state 5.

Author: razvancrainea

modules/siprec/siprec_logic.c

@@ -398,7 +398,7 @@ static int srec_b2b_notify(struct sip_msg *msg, str *key, int type,
 		goto no_recording;
 	}
 
-	if (ss->ctx->dlg->state > DLG_STATE_DELETED) {
+	if (ss->ctx->dlg->state >= DLG_STATE_DELETED) {
 		LM_ERR("dialog already in deleted state!\n");
 		goto no_recording;
 	}
@@ -429,7 +429,11 @@ static int srec_b2b_notify(struct sip_msg *msg, str *key, int type,
 			LM_ERR("Cannot send bye for recording session with key %.*s\n",
 					req.b2b_key->len, req.b2b_key->s);
 	}
-	srec_rtp.copy_delete(ss->ctx->rtp, &ss->instance, &ss->media);
+	if (ss->ctx->dlg->state >= DLG_STATE_DELETED)
+		LM_DBG("rtp context already destroyed!\n");
+	else
+		srec_rtp.copy_delete(ss->ctx->rtp, &ss->instance, &ss->media);
+
 	if (ss->flags & SIPREC_STARTED)
 		raise_siprec_stop_event(ss);
 	srec_logic_destroy(ss, 0);