Date: Sun, 08 Jun 2014 21:12:56 -0500 From: Pedro Giffuni <pfg@FreeBSD.org> To: Bryan Drewery <bdrewery@FreeBSD.org>, Alfred Perlstein <bright@mu.org>, Konstantin Belousov <kostikbel@gmail.com> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r267233 - in head: . bin/rmail gnu/usr.bin/binutils/addr2line gnu/usr.bin/binutils/nm gnu/usr.bin/binutils/objcopy gnu/usr.bin/binutils/objdump gnu/usr.bin/binutils/readelf gnu/usr.bin/... Message-ID: <53951828.6030200@FreeBSD.org> In-Reply-To: <5394D823.60106@FreeBSD.org> References: <201406081729.s58HTWkc006213@svn.freebsd.org> <74512A27-DD5F-4D43-BFA1-0AC04E0D08B4@FreeBSD.org> <20140608182728.GX3991@kib.kiev.ua> <5394ABD2.5040009@mu.org> <20140608184451.GZ3991@kib.kiev.ua> <5394B607.1000109@mu.org> <5394C3D8.7040800@FreeBSD.org> <5394D823.60106@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
El 6/8/2014 4:39 PM, Bryan Drewery escribió: > On 6/8/2014 3:13 PM, Pedro Giffuni wrote: >> Hello; >> >> El 6/8/2014 2:14 PM, Alfred Perlstein escribió: >>> On 6/8/14 11:44 AM, Konstantin Belousov wrote: >>>> On Sun, Jun 08, 2014 at 11:30:42AM -0700, Alfred Perlstein wrote: >>>>> On 6/8/14 11:27 AM, Konstantin Belousov wrote: >>>>>> On Sun, Jun 08, 2014 at 05:38:49PM +0000, Bjoern A. Zeeb wrote: >>>>>>> On 08 Jun 2014, at 17:29 , Bryan Drewery <bdrewery@FreeBSD.org> >>>>>>> wrote: >>>>>>> >>>>>>>> Author: bdrewery >>>>>>>> Date: Sun Jun 8 17:29:31 2014 >>>>>>>> New Revision: 267233 >>>>>>>> URL: http://svnweb.freebsd.org/changeset/base/267233 >>>>>>>> >>>>>>>> Log: >>>>>>>> In preparation for ASLR [1] support add WITH_PIE to support >>>>>>>> building with -fPIE. >>>>>>>> >>>>>>>> This is currently an opt-in build flag. Once ASLR support is >>>>>>>> ready and stable >>>>>>>> it should changed to opt-out and be enabled by default along >>>>>>>> with ASLR. >>>>>>>> >>>>>>>> Each application Makefile uses opt-out to ensure that ASLR will >>>>>>>> be enabled by >>>>>>>> default in new directories when the system is compiled with >>>>>>>> PIE/ASLR. [2] >>>>>>>> >>>>>>>> Mark known build failures as NO_PIE for now. >>>>>>> No, no, no, no more NOs! >>>>>>> >>>>>>> I?ll leave it to others who understand the current build system in >>>>>>> days when it?s not broken to fix this entire splattering across all >>>>>>> these Makefiles; we really need a better way for this. >>>>>> I have no words to express my dissatisfaction with this commit. >>>>>> If change to the build of _some_ usermode binaries require patching >>>>>> of loader', csu and rtld Makefiles, obviously it is done wrong. >>>>>> >>>>>> Why almost half of the binaries require opt-out ? >>>>>> >>>>>> PLEASE REVERT THIS. >>>>> Wait. Does this not serve as a useful stake in the ground for >>>>> people to >>>>> come in and update things? Instead of asking to back out, shouldn't we >>>>> be doing an announcement "ok folks, it's now time to fix this!" and >>>>> move >>>>> forward? Otherwise we may never get any pie. >>>> Let me reformulate. >>>> >>>> Somebody commits broken change, despite it was pointed out by many >>>> before the commit. From the changes it is obvious that people which >>>> proposed it do not understand what they hack on. And then, somebody else >>>> must run and 'fix' previously non-broken code. >>>> >>>> Sure, you get the pie. >>> Sure, but hasn't the default stayed unchanged? >>> >>> It seems like you have to enable ASLR first before you see all the >>> breakage. Right now it seems like goal was to document what even >>> compiles versus doesn't compile with ASLR. Afaik there is not setting >>> of ASLR on by default. >>> >> >> FWIW, and with huge respect to the people working on it, I have come to >> the conclusion that ASLR is useless. The fact that MS and Apple enable >> it now by default is not really a point in favor of the technology as >> the workarounds became popular and finer randomization won't help[1]. >> >> I am also worried about the performance: Redhat created PIE but >> backpedaled when they noticed the performance impact and AFAICT only use >> PIE in a restricted set of binaries. >> >> I would like to see these as an option but I don't think it should ever >> be made the default. Yes, I am aware these patches don't turn anything >> by default but I (and probably others) am suspecting such a switch may >> be thrown upon us without much discussion. >> >> >>> There has to be a way to call out what works and what doesn't work and >>> form a transition from a world with no ASLR to one with some ASLR and >>> eventually one with almost entirely ASLR coverage. I'm not sure it can >>> be done in one fell swoop. Hooks like this in -current allow for this >>> to be done as a group effort. >>> >>> It would be very unlikely that we retain the semantics all the way until >>> a -stable release. >>> >> >> I am not (yet) criticizing the patches to the build system as I want to >> preserve my innocence ;) ... but perhaps if the semantics are not >> finalized this should be done in a branch. It is my opinion that in >> general we are not using SVN branches as much as we should. >> >> Pedro. >> >> For reference: >> >> [1] http://youtu.be/dkZ9zdSRQYM > > Yes there are performance implications. No, the default of PIE and ASLR > won't be done without discussion. > Sounds fair enough for me, thanks! For the record, despite my general disagreement around making it default, I do appreciate the enthusiasm with which Shawn and Oliver are taking these security enhancement projects and Bryan's willingness to wear the asbestos pants here. Pedro.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?53951828.6030200>