fixes crash in chan_console

There is a race condition between console_hangup()
and start_stream().  It is possible for console_hangup()
to be called and then the stream thread to begin after the hangup.
To avoid this a check in start_stream() to make sure the pvt-owner
still exists while the pvt lock is held is made.  If the owner
is gone that means the channel hung up and start_stream should
be aborted.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@262236 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_console.c b/channels/chan_console.c
index 93a51ae..6c566e9 100644 (file)
--- a/channels/chan_console.c
+++ b/channels/chan_console.c
@@ -277,6 +277,10 @@ static void *stream_monitor(void *data)
                res = Pa_ReadStream(pvt->stream, buf, sizeof(buf) / sizeof(int16_t));
                pthread_testcancel();
 
+               if (!pvt->owner) {
+                       return NULL;
+               }
+
                if (res == paNoError)
                        ast_queue_frame(pvt->owner, &f);
        }
@@ -352,7 +356,10 @@ static int start_stream(struct console_pvt *pvt)
 
        console_pvt_lock(pvt);
 
-       if (pvt->streamstate)
+       /* It is possible for console_hangup to be called before the
+        * stream is started, if this is the case pvt->owner will be NULL
+        * and start_stream should be aborted. */
+       if (pvt->streamstate || !pvt->owner)
                goto return_unlock;
 
        pvt->streamstate = 1;