cygwin build SEGV

Corinna Vinschen
Wed Sep 5 13:57:00 GMT 2001

On Thu, Sep 06, 2001 at 12:23:44AM +0400, egor duda wrote:
> Hi!
> Wednesday, 05 September, 2001 Christopher Faylor wrote:
> ok, i've reproduced something similar and i believe i know the reason.
> in my case set_nt_attribute is called with alloca()ed buffer of size
> 256, but actual security descriptor is 268 bytes long. Bang. Stack
> corrupted. This is a workaround, though i think alloc_sd should check
> buffer size, but i cannot produce a patch for this right now.
> hopefully, 4k is enough for any sd. And yes, i think it's a
> show-stopper.

Gosh! I was pretty sure that 256 is always enough in these cases.
In my own tests I got always _168_ byte SDs. Am I assuming right
that bigger SDs are caused by propagating additional user rights
from the parent dir?

Since other function are using 4K SD buffers as well I don't
think it's useful to develop something new here for now. The
4K should be enough for a while. I will keep that problem in
mind, though.

Thanks for tracking that down. Go ahead and check it in.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Developer                      
Red Hat, Inc.

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