res_pjsip_session: Ensure reused streams have correct bundle group

When a bundled stream is removed, its bundle_group is reset to -1.
If that stream is later reused, the bundle parameters on session
media need to be reset correctly it could mistakenly be rebundled
with a stream that was removed and never reused.  Since the removed
stream has no rtp instance, a crash will result.

Change-Id: Ie2b792220f9291587ab5f9fd123145559dba96d7

diff --git a/res/res_pjsip_session.c b/res/res_pjsip_session.c
index 980a1e99d16bb83bfcb5d136904262e6add368fa..9ad5577c3cff8429d4ccc24260ae797629876e10 100644 (file)
--- a/res/res_pjsip_session.c
+++ b/res/res_pjsip_session.c
@@ -487,6 +487,20 @@ struct ast_sip_session_media *ast_sip_session_media_state_add(struct ast_sip_ses
                /* A stream can never exist without an accompanying media session */
                if (session_media->type == type) {
                        ao2_ref(session_media, +1);
+                       /*
+                        * If this session_media was previously removed, its bundle group was probably reset
+                        * to -1 so if bundling is enabled on the endpoint, we need to reset it to 0, set
+                        * the bundled flag and reset its mid.
+                        */
+                       if (session->endpoint->media.bundle && session_media->bundle_group == -1) {
+                               session_media->bundled = session->endpoint->media.webrtc;
+                               session_media->bundle_group = 0;
+                               ast_free(session_media->mid);
+                               if (ast_asprintf(&session_media->mid, "%s-%d", ast_codec_media_type2str(type), position) < 0) {
+                                       ao2_ref(session_media, -1);
+                                       return NULL;
+                               }
+                       }
                } else {
                        session_media = NULL;
                }