X-Recipient: archive-cygwin@delorie.com X-Original-To: cygwin@cygwin.com Delivered-To: cygwin@cygwin.com DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 6E864385ED4A Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=roc.cs.umass.edu Authentication-Results: sourceware.org; spf=none smtp.mailfrom=moss@roc.cs.umass.edu From: Eliot Moss Mime-Version: 1.0 (1.0) Subject: Re: Mandatory ASLR breaks Cygwin - Windows 10 Date: Tue, 25 Aug 2020 10:34:31 -0400 Message-Id: <4AA035EB-1325-4C1B-B399-28FC9176F203@roc.cs.umass.edu> References: In-Reply-To: To: Alexandria Cortez X-Mailer: iPhone Mail (17G68) X-Spam-Status: No, score=1.5 required=5.0 tests=BAYES_20, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, KAM_NUMSUBJECT, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=no autolearn_force=no version=3.4.2 X-Spam-Level: * X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: cygwin@cygwin.com X-Mailman-Version: 2.1.29 List-Id: General Cygwin discussions and problem reports List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cygwin@cygwin.com Content-Type: text/plain; charset="utf-8" Sender: "Cygwin" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by delorie.com id 07PEZ5xf001141 It’s intentional; too long to explain in detail on phone, but fork requires each dll to load in the child at the same address as in the parent, and ASLR interferes with achieving that. Sent from my iPhone > On Aug 25, 2020, at 10:17 AM, Alexandria Cortez wrote: > > I was experimenting with security settings this morning on windows, and > after changing Mandatory ASLR (Windows Security -> App and Browser Control > -> Exploit Protection) to default on, no Cygwin programs that rely on the > Cygwin dll would start, stating that a resource was temporarily unavailable > and could not fork. Rebasell, bash, you name it crashed and would not start. > After some investigation, turning off that setting allows Cygwin to work. > > > > Now the next question: why does this not work? Is this intended behavior or > a bug? Having that setting turned on seems like a good idea from a security > standpoint, and who knows it may eventually become default. > > > > Regards, > > Alexandria C. > > > -- > Problem reports: https://cygwin.com/problems.html > FAQ: https://cygwin.com/faq/ > Documentation: https://cygwin.com/docs.html > Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple