fix rare accidental null pointer deref

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@16838 d0543943-73ff-0310-b7d9-9358b9ac24b2

diff --git a/src/switch_core_codec.c b/src/switch_core_codec.c
index ae84d08c08d12ebdc23b61db9022bcf27ef23bbd..af9bf4e285835898b4b19a89ef1e98fe085370b8 100644 (file)
--- a/src/switch_core_codec.c
+++ b/src/switch_core_codec.c
@@ -113,13 +113,21 @@ SWITCH_DECLARE(switch_status_t) switch_core_session_set_read_codec(switch_core_s
        if (codec) {
                if (!session->real_read_codec) {
                        session->read_codec = session->real_read_codec = codec;
-                       session->read_impl = *codec->implementation;
+                       if (codec->implementation) {
+                               session->read_impl = *codec->implementation;
+                       } else {
+                               memset(&session->read_impl, 0, sizeof(session->read_impl));
+                       }
                } else {
                        switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "%s Push codec %s:%d\n",
                                                          switch_channel_get_name(session->channel), codec->implementation->iananame, codec->implementation->ianacode);
                        codec->next = session->read_codec;
                        session->read_codec = codec;
-                       session->read_impl = *codec->implementation;
+                       if (codec->implementation) {
+                               session->read_impl = *codec->implementation;
+                       } else {
+                               memset(&session->read_impl, 0, sizeof(session->read_impl));
+                       }
                }
        } else {
                if (session->read_codec == session->real_read_codec) {
@@ -129,7 +137,11 @@ SWITCH_DECLARE(switch_status_t) switch_core_session_set_read_codec(switch_core_s
                if (session->read_codec->next) {
                        switch_codec_t *old = session->read_codec;
                        session->read_codec = session->read_codec->next;
-                       session->read_impl = *session->read_codec->implementation;
+                       if (session->read_codec->implementation) {
+                               session->read_impl = *session->read_codec->implementation;
+                       } else {
+                               memset(&session->read_impl, 0, sizeof(session->read_impl));
+                       }
                        old->next = NULL;
                        switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "%s Restore previous codec %s:%d.\n",
                                                          switch_channel_get_name(session->channel),
@@ -137,7 +149,11 @@ SWITCH_DECLARE(switch_status_t) switch_core_session_set_read_codec(switch_core_s
 
                } else if (session->real_read_codec) {
                        session->read_codec = session->real_read_codec;
-                       session->read_impl = *session->real_read_codec->implementation;
+                       if (session->real_read_codec->implementation) {
+                               session->read_impl = *session->real_read_codec->implementation;
+                       } else {
+                               memset(&session->read_impl, 0, sizeof(session->read_impl));
+                       }
                        switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Restore original codec.\n");
                } else {
                        status = SWITCH_STATUS_FALSE;
@@ -374,7 +390,11 @@ SWITCH_DECLARE(switch_status_t) switch_core_session_set_video_read_codec(switch_
        switch_channel_set_variable(channel, "video_read_rate", tmp);
 
        session->video_read_codec = codec;
-       session->video_read_impl = *codec->implementation;
+       if (codec->implementation) {
+               session->video_read_impl = *codec->implementation;
+       } else {
+               memset(&session->video_read_impl, 0, sizeof(session->video_read_impl));
+       }
   end:
 
        return status;