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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/2434/">https://reviewboard.asterisk.org/r/2434/</a>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Hmm. Looking at the source, there are more functions that assume that the PVT just exist. sip_transfer() follows sip_senddigit_end and propably needs the very same check. It won't hurt.</pre>
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<p>- Olle E</p>
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<p>On April 9th, 2013, 7:35 p.m. CEST, Matt Jordan wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By Matt Jordan.</div>
<p style="color: grey;"><i>Updated April 9, 2013, 7:35 p.m.</i></p>
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<b style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Bugs: </b>
<a href="https://issues.asterisk.org/jira/browse/ASTERISK-20225">ASTERISK-20225</a>
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<b style="color: #575012; font-size: 10pt;">Repository: </b>
Asterisk
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">A race condition can occur between a channel that has a DTMF played back on it from AMI and the underlying SIP dialog receiving a BYE request. The DTMF will be queued up for action on the channel and - while the frames are queued up - a BYE request will be received. The SIP pvt will be removed from the channel and the tech_pvt pointer set to NULL. When the channel lock is released, the frames get processed. This will call either sip_senddigit_begin/sip_senddigit_end and - since the pvt is NULL - the dreaded FRACK error will occur.
(Or you just crash)
This patch does the really simple thing and bails if the pvt pointer is NULL. It's actually valid - there isn't any way for AMI to know that the pvt just got nuked, and chan_sip is locking the channel while it removes the pvt. Sometimes, you just have to check that something isn't NULL before you use it.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">A test I was writing stops crashing. Yay!</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>/branches/1.8/channels/chan_sip.c <span style="color: grey">(384779)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/2434/diff/" style="margin-left: 3em;">View Diff</a></p>
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