[pkg-gnupg-maint] Bug#841143: Bug#841143: Suspected race in gpg1 to gpg2 conversion or agent startup

[Ian Jackson]

Ian Jackson writes ("Re: Bug#841143: [pkg-gnupg-maint] Bug#841143: Suspected race in gpg1 to gpg2 conversion or agent startup"):
> The variable `active_connectionis' in gpg-agent.c seems to be updated
> by multiple threads without any locking.  If it were to get corrupted,
> I think gpg-agent might get stuck trying to exit, with clients which
> had successfully connected at the syscall level.

I fixed this but it didn't help.  I now have a gdb onto a stuck agent,
which has shutdown_pending but is stuck in select.  I think
shutdown_pending must have become 1 between the main loop test and the
entry to select.

This approach to programming is a quite a rich seam of opportunities
for threading bugs.

For example, I think the variables `check_own_socket_running' and
`shutdown_pending' are both accessed willy-nilly on multiple threads
without locking.

Ian.

-- 
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