ZOOKEEPER-4809: Fix do_completion use-after-free when log level is debug #2139
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fanyang89
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| @@ -479,8 +480,9 @@ void *do_completion(void *v) | |||
| pthread_mutex_unlock(&zh->completions_to_process.lock); | |||
| process_completions(zh); | |||
| } | |||
| api_epilog(zh, 0); | |||
| LOG_DEBUG(LOGCALLBACK(zh), "completion thread terminated"); | |||
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Is it more conventional to swap the two statements ? I saw several return api_epilog(zh, rc) patterns. Also, line 460 has same problem.
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Indeed, it would be conventional to log first and then api_epilog().
But api_epilog() does zookeeper_close() when the rc is zero, i.e. the completion thread is still running after the "terminated" output, which could lead to confusion?
…debug The log callback needs to be obtained from freed zhandle when the log level is debug, resulting in used-after-free.
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kezhuw
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@ztzg can you please take a look? |
ztzg
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Mar 18, 2024
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The log callback needs to be obtained from freed zh when the log level is debug, resulting in used-after-free.