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Re: Bug in SMB when multiple scripts are connecting to same host
From: Chris Woodbury <woodbusy () gmail com>
Date: Thu, 31 Mar 2011 13:54:39 -0500


Sorry for the delay in getting back to you. You make a good point about the
maintainability of all those unlocks. Fortunately, those two functions are
already wrapped by another one, start_session(), so I've attached a patch
that moves the mutex to that function. For good measure, I also threw in
some comments warning users away from calling start_session_basic() and
start_session_extended() directly.


On Tue, Mar 15, 2011 at 1:45 AM, David Fifield <david () bamsoftware com>wrote:

On Mon, Feb 28, 2011 at 01:44:34PM -0600, Chris Woodbury wrote:

Thanks for the response. Don't worry about the delay - 'better late than
never' is my motto ;). I hadn't thought of the lockout implications of
separate account lists; so, yes, you certainly wouldn't want to go that
route. With that in mind, I put some more thought into it, and it seems
me that mutexes are the best approach.

I made a patch that adds mutexes to start_session_basic() and
start_session_extended(). My thinking was that the first script to get
would be responsible for finding the right account (or exhausting the
possibilities), and that, once that was done, the other scripts could
along and already have that account waiting for their get_account() call.
had to put in an "unlock" before each of the short-circuit returns; so,
not exactly pretty, but it gets the job done.

Could you rewrite this with wrapper functions to handle the mutexes, so
as to get rid of the need to unlock at every single return? I'm afraid
the way it's written now will be too hard to maintain.

Ron, what do you think of Chris's solution?

David Fifield

Attachment: smb_auth_mutex2.patch

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