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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/1127/">https://reviewboard.asterisk.org/r/1127/</a>
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<a href="https://reviewboard.asterisk.org/r/1127/diff/1/?file=15743#file15743line23638" style="color: black; font-weight: bold; text-decoration: underline;">/tags/1.8.3-rc2/channels/chan_sip.c</a>
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(Diff revision 1)
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<td colspan="4"><pre style="font-size: 8pt; line-height: 140%; margin: 0; ">static int handle_incoming(struct sip_pvt *p, struct sip_request *req, struct ast_sockaddr *addr, int *recount, int *nounlock)</pre></td>
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<td bgcolor="#ffffff" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> *nounlock = 1;</pre></td>
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<td bgcolor="#ffffff" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> *nounlock = 1;</pre></td>
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<td bgcolor="#fdfebc" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> pbx_builtin_setvar_helper(owner, causevar, causeval);</pre></td>
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<td bgcolor="#fdfebc" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> mchan = ast_channel_get_by_name(linkedid);</pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> pbx_builtin_setvar_helper(mchan ? mchan : owner, causevar, causeval);</pre></td>
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<pre style="margin-left: 2em; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">You need to unref mchan after this.</pre>
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<p>- Russell</p>
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<p>On February 25th, 2011, 1:40 p.m., Brett Bryant wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By Brett Bryant.</div>
<p style="color: grey;"><i>Updated 2011-02-25 13:40:19</i></p>
<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;">Use of MASTER_CHANNEL in chan_sip causes pbx_setvar_helper to potentially lock a channel before iterating through the channel container to find the master channel. This violates locking order, and when two threads are doing this at the same time they can both end up in a deadlock holding the channel locks that the others are trying to acquire through the iterator.</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;">Tested functionality of code and accuracy before and after change which removed the use of the MASTER_CHANNEL function.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>/tags/1.8.3-rc2/channels/chan_sip.c <span style="color: grey">(308543)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/1127/diff/" style="margin-left: 3em;">View Diff</a></p>
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