Fix a race condition where the generator can go away

(closes issue #12175, reported by edantie, patched by me)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@107099 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/channel.c b/main/channel.c
index 2cb3b7be38573cdf27679f8085c4b1729b6c39d5..d148cd97d5d6c6883864ba79552c13544f9baac7 100644 (file)
--- a/main/channel.c
+++ b/main/channel.c
@@ -1560,9 +1560,13 @@ static int generator_force(const void *data)
        ast_channel_lock(chan);
        tmp = chan->generatordata;
        chan->generatordata = NULL;
-       generate = chan->generator->generate;
+       if (chan->generator)
+               generate = chan->generator->generate;
        ast_channel_unlock(chan);
 
+       if (!tmp || !generate)
+               return 0;
+
        res = generate(chan, tmp, 0, 160);
 
        chan->generatordata = tmp;