diff --git a/channels/chan_pjsip.c b/channels/chan_pjsip.c index b6bfeb5b4d704ae014abaeb3e55b34b7f2de950f..cad0a7c5f5744dff772f7d51451955339b960929 100644 --- a/channels/chan_pjsip.c +++ b/channels/chan_pjsip.c @@ -490,7 +490,6 @@ static int answer(void *data) struct ast_sip_session *session = data; if (session->inv_session->state == PJSIP_INV_STATE_DISCONNECTED) { - ao2_ref(session, -1); return 0; } @@ -507,8 +506,6 @@ static int answer(void *data) ast_sip_session_send_response(session, packet); } - ao2_ref(session, -1); - return (status == PJ_SUCCESS) ? 0 : -1; } @@ -516,19 +513,27 @@ static int answer(void *data) static int chan_pjsip_answer(struct ast_channel *ast) { struct ast_sip_channel_pvt *channel = ast_channel_tech_pvt(ast); + struct ast_sip_session *session; if (ast_channel_state(ast) == AST_STATE_UP) { return 0; } ast_setstate(ast, AST_STATE_UP); + session = ao2_bump(channel->session); - ao2_ref(channel->session, +1); - if (ast_sip_push_task(channel->session->serializer, answer, channel->session)) { + /* the answer task needs to be pushed synchronously otherwise a race condition + can occur between this thread and bridging (specifically when native bridging + attempts to do direct media) */ + ast_channel_unlock(ast); + if (ast_sip_push_task_synchronous(session->serializer, answer, session)) { ast_log(LOG_WARNING, "Unable to push answer task to the threadpool. Cannot answer call\n"); - ao2_cleanup(channel->session); + ao2_ref(session, -1); + ast_channel_lock(ast); return -1; } + ao2_ref(session, -1); + ast_channel_lock(ast); return 0; }