Messages in this thread | | | Date | Tue, 20 May 2008 13:27:57 -0500 | From | Michael Halcrow <> | Subject | Re: [Q] eCryptFS race window? |
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On Tue, May 20, 2008 at 09:03:21PM +0400, Cyrill Gorcunov wrote: > it seems there is a few potential race window in eCryptFS which I > was trying to fix but it requires more deeper eCrypFS knowledge that > have (at least only by understanding eCryptFS in big picture it is > possible to fix this problem by elegant path). So what is the > problem - the procedures > > ecryptfs_miscdev_poll > ecryptfs_miscdev_read > > does take ecryptfs_daemon_hash_mux mutex and then daemon->mux _but_ > releases them not in exactly backward order as it should. My patches > (not in mainline but you saw them) was screwed up 'cause > mutex_is_locked could release mutex acquired by another process and > that is wrong. But I've a hope that I'm simply *wrong* about this > possible races ;) Take a look please.
I cannot find an execution path whereby one of the two must re-acquire ecryptfs_daemon_hash_mux in order to release daemon->mux, so I do not think we will ever have deadlock between those two functions.
Mike
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