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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/3055/">https://reviewboard.asterisk.org/r/3055/</a>
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<a href="https://reviewboard.asterisk.org/r/3055/diff/2/?file=49178#file49178line825" style="color: black; font-weight: bold; text-decoration: underline;">/branches/1.8/main/pbx.c</a>
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(Diff revision 2)
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<td colspan="4"><pre style="font-size: 8pt; line-height: 140%; margin: 0; ">struct ast_app;</pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; ">int pbx_rdlock_extens(void);</pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; ">int pbx_wrlock_extens(void);</pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; ">int pbx_unlock_extens(void);</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;">Since these functions are local to pbx.c, declare them static. Also use "static" on the function definitions.
Since the new lock is a mutex, why do you have read and write lock functions? </pre>
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<a href="https://reviewboard.asterisk.org/r/3055/diff/2/?file=49178#file49178line7804" style="color: black; font-weight: bold; text-decoration: underline;">/branches/1.8/main/pbx.c</a>
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(Diff revision 2)
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<td colspan="4"><pre style="font-size: 8pt; line-height: 140%; margin: 0; ">void ast_merge_contexts_and_delete(struct ast_context **extcontexts, struct ast_hashtab *exttable, const char *registrar)</pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span>pbx_wrlock_extens();</pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span>pbx_unlock_extens();</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;">I don't understand what this is supposed to be doing. This lock doesn't actually protect anything. I suspect this may narrow the window of the race condition but it seems like whatever dangerous operation was occurring can still occur since that dangerous operation is not surrounded by the lock.</pre>
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<p>- Mark Michelson</p>
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<p>On December 6th, 2013, 9:41 p.m. UTC, Scott Griepentrog wrote:</p>
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<div>Review request for Asterisk Developers and Matt Jordan.</div>
<div>By Scott Griepentrog.</div>
<p style="color: grey;"><i>Updated Dec. 6, 2013, 9:41 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/AST-1179">AST-1179</a>,
<a href="https://issues.asterisk.org/jira/browse/AST-1246">AST-1246</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;">During dialplan execution in pbx_extension_helper(), the contexts global read lock is used prevent changes to the dialplan. This patch adds a lock between that point and until after the extension previously found is no longer being referenced -- after variable substitution, but before app execution. This new lock prevents the extension's allocation from being released by module reload when it is still being used in an expression evaluation.
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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;">Testsuite test 'dialplan_stress' (https://reviewboard.asterisk.org/r/3056/) created to isolate this problem and test this fix.</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/main/pbx.c <span style="color: grey">(403430)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/3055/diff/" style="margin-left: 3em;">View Diff</a></p>
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