From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailsrv.cs.umass.edu (mailsrv.cs.umass.edu [128.119.240.136]) by sourceware.org (Postfix) with ESMTPS id 6E864385ED4A for ; Tue, 25 Aug 2020 14:34:33 +0000 (GMT) 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 Received: from [10.198.31.77] (199.sub-174-255-64.myvzw.com [174.255.64.199]) by mailsrv.cs.umass.edu (Postfix) with ESMTPSA id EB3BD401DC92; Tue, 25 Aug 2020 10:34:32 -0400 (EDT) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable 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: Cc: cygwin@cygwin.com 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 Precedence: list List-Id: General Cygwin discussions and problem reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Aug 2020 14:34:34 -0000 It=E2=80=99s intentional; too long to explain in detail on phone, but fork r= equires each dll to load in the child at the same address as in the parent, a= nd ASLR interferes with achieving that. Sent from my iPhone > On Aug 25, 2020, at 10:17 AM, Alexandria Cortez wr= ote: >=20 > =EF=BB=BFI was experimenting with security settings this morning on window= s, 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 unavailabl= e > and could not fork. Rebasell, bash, you name it crashed and would not star= t. > After some investigation, turning off that setting allows Cygwin to work. >=20 >=20 >=20 > Now the next question: why does this not work? Is this intended behavior o= r > a bug? Having that setting turned on seems like a good idea from a securit= y > standpoint, and who knows it may eventually become default. >=20 >=20 >=20 > Regards, >=20 > Alexandria C. >=20 > > -- > 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