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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/1752/">https://reviewboard.asterisk.org/r/1752/</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;">I don't like it.
Correct me if I'm wrong, but you're removing it there, so it won't show up in this bit:
AST_LIST_TRAVERSE_SAFE_BEGIN(&module_list, mod, entry) {
if (!final && mod->usecount) {
continue;
}
AST_LIST_REMOVE_CURRENT(entry);
if (mod->flags.running && !mod->flags.declined && mod->info->unload) {
mod->info->unload();
}
AST_LIST_HEAD_DESTROY(&mod->users);
free(mod);
somethingchanged = 1;
}
AST_LIST_TRAVERSE_SAFE_END;
But who does the free'ing of mod then? (As an aside, shouldn't that be ast_free() instead of free()?)</pre>
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<p>- wdoekes</p>
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<p>On February 18th, 2012, 1:31 p.m., Terry Wilson wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By Terry Wilson.</div>
<p style="color: grey;"><i>Updated Feb. 18, 2012, 1:31 p.m.</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;">res_calendar calls ast_unload_resource for the related tech modules when it is unloaded. If this happens through a 'core stop gracefully', then it will be unloading the tech modules that are already in the list that is being traversed (supposedly safely) for unloading, eventually causing a double free. The problem seems to be that ast_unload_resource, while it calls the unload() callback function for the module, does not actually unlink the module from the list of modules. So the AST_LIST_TRAVERSE_SAFE_BEGIN {} still iterates over the unloaded module.
This patch causes ast_unload_resource to call AST_LIST_REMOVE on successfully unloaded modules.</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;">Scenario: Start Asterisk with res_calendar and assorted calendar tech modules loaded. Run 'core stop gracefully'.
Before patch: Crash.
After patch: No crash.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>/trunk/main/loader.c <span style="color: grey">(355783)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/1752/diff/" style="margin-left: 3em;">View Diff</a></p>
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