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Michael K. Edwards commented on ZOOKEEPER-2320: ----------------------------------------------- Reproducible in current branch-3.5? > C-client crashes when removing watcher asynchronously in "local" mode > --------------------------------------------------------------------- > > Key: ZOOKEEPER-2320 > URL: https://issues.apache.org/jira/browse/ZOOKEEPER-2320 > Project: ZooKeeper > Issue Type: Bug > Components: c client > Affects Versions: 3.5.1 > Reporter: Hadriel Kaplan > Assignee: Abraham Fine > Priority: Major > Labels: pull-request-available > Attachments: ZOOKEEPER-2320.patch, ZOOKEEPER-2320.patch > > Time Spent: 1h 10m > Remaining Estimate: 0h > > The C-client library will crash when invoking the asynchronous > {{zoo_aremove_watchers()}} API function with the '{{local}}' argument set to > 1. > The reason is: if the local argument is 1/true, then the code does > '{{notify_sync_completion((struct sync_completion *)data);}}' But casting the > '{{data}}' variable to a {{sync_completion}} struct pointer is bogus/invalid, > and when it's later handles as that struct pointer it's accessing invalid > memory. > As a side note: it will work ok when called _synchronously_ through > {{zoo_remove_watchers()}}, because that function creates a > {{sync_completion}} struct and passes it to the asynch > {{zoo_aremove_watchers()}}, but it will not work ok when the asynch function > is used directly for the reason stated perviously. > Another side note: the docs state that setting the 'local' flag makes the > C-client remove the watcher "even if there is no server connection" - but > really it makes the C-client remove the watcher without notifying the server > at *all*, even if the connection to a server is up. (well... that's what it > would do if it didn't just crash instead ;) -- This message was sent by Atlassian JIRA (v7.6.3#76005)