net/asterisk-16.x/patches/160-AST-2019-004-16.patch

   1 From 69ed619a6d9b64a297d3099b6455756912e21d0b Mon Sep 17 00:00:00 2001
   2 From: Kevin Harwell <kharwell@digium.com>
   3 Date: Tue, 20 Aug 2019 15:05:45 -0500
   4 Subject: [PATCH] AST-2019-004 - res_pjsip_t38.c: Add NULL checks before using session media
   5
   6 After receiving a 200 OK with a declined stream in response to a T.38
   7 initiated re-invite Asterisk would crash when attempting to dereference
   8 a NULL session media object.
   9
  10 This patch checks to make sure the session media object is not NULL before
  11 attempting to use it.
  12
  13 ASTERISK-28495
  14 patches:
  15   ast-2019-004.patch submitted by Alexei Gradinari (license 5691)
  16
  17 Change-Id: I168f45f4da29cfe739acf87e597baa2aae7aa572
  18 ---
  19
  20 diff --git a/res/res_pjsip_t38.c b/res/res_pjsip_t38.c
  21 index 11804e2..e5c6090 100644
  22 --- a/res/res_pjsip_t38.c
  23 +++ b/res/res_pjsip_t38.c
  24 @@ -203,7 +203,6 @@
  25  {
  26         RAII_VAR(struct ast_sip_session *, session, obj, ao2_cleanup);
  27         RAII_VAR(struct ast_datastore *, datastore, ast_sip_session_get_datastore(session, "t38"), ao2_cleanup);
  28 -       struct ast_sip_session_media *session_media;
  29
  30         if (!datastore) {
  31                 return 0;
  32 @@ -212,8 +211,7 @@
  33         ast_debug(2, "Automatically rejecting T.38 request on channel '%s'\n",
  34                 session->channel ? ast_channel_name(session->channel) : "<gone>");
  35
  36 -       session_media = session->pending_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
  37 -       t38_change_state(session, session_media, datastore->data, T38_REJECTED);
  38 +       t38_change_state(session, NULL, datastore->data, T38_REJECTED);
  39         ast_sip_session_resume_reinvite(session);
  40
  41         return 0;
  42 @@ -322,28 +320,37 @@
  43                 int index;
  44
  45                 session_media = session->active_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
  46 -               t38_change_state(session, session_media, state, T38_ENABLED);
  47 +               if (!session_media) {
  48 +                       ast_log(LOG_WARNING, "Received %d response to T.38 re-invite on '%s' but no active session media\n",
  49 +                                       status.code, session->channel ? ast_channel_name(session->channel) : "unknown channel");
  50 +               } else {
  51 +                       t38_change_state(session, session_media, state, T38_ENABLED);
  52
  53 -               /* Stop all the streams in the stored away active state, they'll go back to being active once
  54 -                * we reinvite back.
  55 -                */
  56 -               for (index = 0; index < AST_VECTOR_SIZE(&state->media_state->sessions); ++index) {
  57 -                       struct ast_sip_session_media *session_media = AST_VECTOR_GET(&state->media_state->sessions, index);
  58 +                       /* Stop all the streams in the stored away active state, they'll go back to being active once
  59 +                        * we reinvite back.
  60 +                        */
  61 +                       for (index = 0; index < AST_VECTOR_SIZE(&state->media_state->sessions); ++index) {
  62 +                               struct ast_sip_session_media *session_media = AST_VECTOR_GET(&state->media_state->sessions, index);
  63
  64 -                       if (session_media && session_media->handler && session_media->handler->stream_stop) {
  65 -                               session_media->handler->stream_stop(session_media);
  66 +                               if (session_media && session_media->handler && session_media->handler->stream_stop) {
  67 +                                       session_media->handler->stream_stop(session_media);
  68 +                               }
  69                         }
  70 +
  71 +                       return 0;
  72                 }
  73         } else {
  74                 session_media = session->pending_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
  75 -               t38_change_state(session, session_media, state, T38_REJECTED);
  76 -
  77 -               /* Abort this attempt at switching to T.38 by resetting the pending state and freeing our stored away active state */
  78 -               ast_sip_session_media_state_free(state->media_state);
  79 -               state->media_state = NULL;
  80 -               ast_sip_session_media_state_reset(session->pending_media_state);
  81         }
  82
  83 +       /* If no session_media then response contained a declined stream, so disable */
  84 +       t38_change_state(session, NULL, state, session_media ? T38_REJECTED : T38_DISABLED);
  85 +
  86 +       /* Abort this attempt at switching to T.38 by resetting the pending state and freeing our stored away active state */
  87 +       ast_sip_session_media_state_free(state->media_state);
  88 +       state->media_state = NULL;
  89 +       ast_sip_session_media_state_reset(session->pending_media_state);
  90 +
  91         return 0;
  92  }
  93
  94 @@ -426,12 +433,10 @@
  95                 /* Negotiation can not take place without a valid max_ifp value. */
  96                 if (!parameters->max_ifp) {
  97                         if (data->session->t38state == T38_PEER_REINVITE) {
  98 -                               session_media = data->session->pending_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
  99 -                               t38_change_state(data->session, session_media, state, T38_REJECTED);
 100 +                               t38_change_state(data->session, NULL, state, T38_REJECTED);
 101                                 ast_sip_session_resume_reinvite(data->session);
 102                         } else if (data->session->t38state == T38_ENABLED) {
 103 -                               session_media = data->session->active_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
 104 -                               t38_change_state(data->session, session_media, state, T38_DISABLED);
 105 +                               t38_change_state(data->session, NULL, state, T38_DISABLED);
 106                                 ast_sip_session_refresh(data->session, NULL, NULL, NULL,
 107                                         AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1, state->media_state);
 108                                 state->media_state = NULL;
 109 @@ -454,6 +459,11 @@
 110                         state->our_parms.version = MIN(state->our_parms.version, state->their_parms.version);
 111                         state->our_parms.rate_management = state->their_parms.rate_management;
 112                         session_media = data->session->pending_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
 113 +                       if (!session_media) {
 114 +                               ast_log(LOG_ERROR, "Failed to negotiate parameters for reinvite on channel '%s' (No pending session media).\n",
 115 +                                       data->session->channel ? ast_channel_name(data->session->channel) : "unknown channel");
 116 +                               break;
 117 +                       }
 118                         ast_udptl_set_local_max_ifp(session_media->udptl, state->our_parms.max_ifp);
 119                         t38_change_state(data->session, session_media, state, T38_ENABLED);
 120                         ast_sip_session_resume_reinvite(data->session);
 121 @@ -468,8 +478,13 @@
 122                         }
 123                         state->our_parms = *parameters;
 124                         session_media = media_state->default_session[AST_MEDIA_TYPE_IMAGE];
 125 +                       if (!session_media) {
 126 +                               ast_log(LOG_ERROR, "Failed to negotiate parameters on channel '%s' (No default session media).\n",
 127 +                                       data->session->channel ? ast_channel_name(data->session->channel) : "unknown channel");
 128 +                               break;
 129 +                       }
 130                         ast_udptl_set_local_max_ifp(session_media->udptl, state->our_parms.max_ifp);
 131 -                       t38_change_state(data->session, session_media, state, T38_LOCAL_REINVITE);
 132 +                       t38_change_state(data->session, NULL, state, T38_LOCAL_REINVITE);
 133                         ast_sip_session_refresh(data->session, NULL, t38_reinvite_sdp_cb, t38_reinvite_response_cb,
 134                                 AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1, media_state);
 135                 }
 136 @@ -478,12 +493,10 @@
 137         case AST_T38_REFUSED:
 138         case AST_T38_REQUEST_TERMINATE:         /* Shutdown T38 */
 139                 if (data->session->t38state == T38_PEER_REINVITE) {
 140 -                       session_media = data->session->pending_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
 141 -                       t38_change_state(data->session, session_media, state, T38_REJECTED);
 142 +                       t38_change_state(data->session, NULL, state, T38_REJECTED);
 143                         ast_sip_session_resume_reinvite(data->session);
 144                 } else if (data->session->t38state == T38_ENABLED) {
 145 -                       session_media = data->session->active_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
 146 -                       t38_change_state(data->session, session_media, state, T38_DISABLED);
 147 +                       t38_change_state(data->session, NULL, state, T38_DISABLED);
 148                         ast_sip_session_refresh(data->session, NULL, NULL, NULL, AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1, state->media_state);
 149                         state->media_state = NULL;
 150                 }
 151 @@ -493,6 +506,11 @@
 152
 153                 if (data->session->t38state == T38_PEER_REINVITE) {
 154                         session_media = data->session->pending_media_state->default_session[AST_MEDIA_TYPE_IMAGE];
 155 +                       if (!session_media) {
 156 +                               ast_log(LOG_ERROR, "Failed to request parameters for reinvite on channel '%s' (No pending session media).\n",
 157 +                                       data->session->channel ? ast_channel_name(data->session->channel) : "unknown channel");
 158 +                               break;
 159 +                       }
 160                         parameters.max_ifp = ast_udptl_get_far_max_ifp(session_media->udptl);
 161                         parameters.request_response = AST_T38_REQUEST_NEGOTIATE;
 162                         ast_queue_control_data(data->session->channel, AST_CONTROL_T38_PARAMETERS, &parameters, sizeof(parameters));
 163 @@ -788,7 +806,7 @@
 164
 165         if ((session->t38state == T38_REJECTED) || (session->t38state == T38_DISABLED)) {
 166                 ast_debug(3, "Declining; T.38 state is rejected or declined\n");
 167 -               t38_change_state(session, session_media, state, T38_DISABLED);
 168 +               t38_change_state(session, NULL, state, T38_DISABLED);
 169                 return 0;
 170         }
 171