search for: interposing

----- Original Message ----- > From: "Eric Christopher" <echristo at gmail.com> > To: "Reid Kleckner" <rnk at google.com>, "Hal Finkel" <hfinkel at anl.gov> > Cc: "llvm-dev" <llvm-dev at lists.llvm.org> > Sent: Tuesday, November 29, 2016 11:34:56 AM > Subject: Re: [llvm-dev] RFC: Add an "interposible" linkage

I think that all makes sense. You're just adding the missing non-ODR conterpart of 'external' linkage. I could imagine having "external / external_odr" linkage for example. That said, do you think we should take the opportunity to split out a bit for interposability so that we can kill off the *_odr linkage variants? Today's non-ODR weak functions would look more like

On Mon, Feb 22, 2016 at 11:18 PM, Chandler Carruth <chandlerc at gmail.com> wrote: >> # step A: Introduce an `interposable` function attribute >> >> We can bike shed on the name and the exact specification, but the >> general idea is that you cannot do IPA / IPO over callsites calling >> `interposable` functions without inlining them. This attribute will

...need be that may not be an enormous issue: You could specify a custom segment in your executable with zero file size and a vm size the blocks out the address range you need and then unmap it. There may be practical limits on it that prevent you from achieving what you want. You could use implicit interposing. This is a feature add so that ASAN binaries can avoid the the whole re-exec with DYLD_INSERT_LIBRARIES issue. It is not guaranteed to be stable, but in practice it is probably the most stable option short of using a hypervisor. The way it works: Define all the symbols in a dylib along with an int...

Hi everyone, Clang/LLVM's support for ELF interposition is in a confusing state, and I propose making a few (hopefully simple) adjustments in order to bring our model into a self-consistent state. The problem: On ELF systems, global symbols can be interposed. This means, for example, that calls to global functions in some (shared) library defined in that same library might end up being

Assuming everyone is on the same page, here's a rough high level agenda: # step A: Introduce an `interposable` function attribute We can bike shed on the name and the exact specification, but the general idea is that you cannot do IPA / IPO over callsites calling `interposable` functions without inlining them. This attribute will (usually) have to be used on function bodies that can

You present a good case for not using "protected" visibility in ELF, despite it being exactly what it is supposed to mean. >From what http://www.airs.com/blog/archives/307 says, it sounds like the *correctness* issue with protected visibility is because LLVM is doing it wrong -- not an intrinsic property of protected visibility in ELF, or even ELF/x86. The blog says that the compiler

On Tue, Feb 23, 2016 at 10:55 AM, Chandler Carruth <chandlerc at gmail.com> wrote: >> Part of the challenge here is to specify the attribute in a way that >> allows inlining, but not IPA without inlining. In fact, maybe it is >> best to not call it "interposable" at all? > > > Yea, this is something *very* different from interposable. GCC and other >

----- Original Message ----- > From: "James Y Knight" <jyknight at google.com> > To: "Hal Finkel" <hfinkel at anl.gov> > Cc: "Sanjoy Das" <sanjoy at playingwithpointers.com>, "llvm-dev" > <llvm-dev at lists.llvm.org> > Sent: Monday, February 29, 2016 9:31:24 AM > Subject: Re: [llvm-dev] Possible soundness issue with

Hi there was a mail a while back on this list about using the LD_PRELOAD feature on Solaris in order to override the location of nsswitch.conf for smbd so only it would use winbindd. I did some digging and came up with the code at the bottom of this mail ( I've overridden every file open call I could find, but I think it's only the _open() call which is actually necessary ). Initial

I''d like to see if we can use DTrace to as the kernel implementation of the BSD systrace security policy system (http://www.systrace.org). I don''t really want to port systrace to Solaris because I think with DTrace we already have all the necessary in kernel hooks to do this. With systrace you express things like: "httpd can bind to port 80 but not any other port, it

> On Mar 11, 2016, at 9:56 AM, Reid Kleckner <rnk at google.com> wrote: > > On Fri, Mar 11, 2016 at 9:41 AM, John McCall <rjmccall at apple.com <mailto:rjmccall at apple.com>> wrote: > Okay, so, it sounds to me like LLVM basically treats strong definitions as protected, then. Should we just formalize that? > > I guess the proposal here would be: > 1.

I want to create my own "[" function (for use on vectors, matrices, arrays, etc.), which calls the stock R "[", does some additional work, and then finally returns the modified result. But, how do I properly call the stock R "[" function? It takes a varying number of positional arguments, and its R-level closure is just: .Primitive("[") It's

+kledzik at apple.com The dynamic runtime is using dylib interposition (google for "__DATA,__interpose). If I'm understanding correctly (Nick, can you please confirm this?) this allows to interpose the function regardless of the two-level namespace. The support for dynamic runtime in ASan is almost there. But the new interposition method has revealed some issues with the allocator which

> On Jun 6, 2017, at 4:08 PM, Michael Clark via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > Hi Folks, > > I’m working on a port of musl libc to macos (arch triple is “x86_64-xnu-musl”) to solve some irreconcilable issues I’m having with libSystem.dylib. I don’t want to use glibc for various reasons, mainly because I want to static link. I have static PIE + ASLR working

> On Mar 11, 2016, at 8:33 AM, Reid Kleckner <rnk at google.com> wrote: > On Thu, Mar 10, 2016 at 10:32 PM, John McCall via llvm-dev <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote: > I mean, I’ve never really liked ELF’s stance on symbol interposition, but taking it as given, I’m not sure I agree that it’s reasonable to carve out virtual functions

Hi- I am running Samba 2.2.5 on Solaris 8 with winbind and pam configured. I have the following in my nsswitch.conf: passwd: files winbind group: files winbind Now local users on the Solaris 8 machine cannot change there password using the passwd command: Here is the sample output: # passwd michasp1 Enter new password: Enter new password again: Supported configurations for passwd

On Tue, Dec 04, 2012 at 09:46:09AM -0800, Alexander Potapenko wrote: > +kledzik at apple.com > The dynamic runtime is using dylib interposition (google for > "__DATA,__interpose). > If I'm understanding correctly (Nick, can you please confirm this?) > this allows to interpose the function regardless of the two-level > namespace. > The support for dynamic runtime in

On Feb 26, 2016 8:50 PM, "Hal Finkel" <hfinkel at anl.gov> wrote: > *From: *"James Y Knight via llvm-dev" <llvm-dev at lists.llvm.org> > *To: *"Sanjoy Das" <sanjoy at playingwithpointers.com> > *Cc: *"llvm-dev" <llvm-dev at lists.llvm.org> > *Sent: *Thursday, February 25, 2016 1:41:43 PM > *Subject: *Re: [llvm-dev]

Howdy. I have a application I'm developing where I need to encrypt the data inside an OGG stream. I will be using a regular block cypher (AES, or others... configurable); and I would like to encrypt the pages in an OGG stream. I'm thinking that if I sit my decrypter in between the reading application and the encrypted file, you should be able to use all the normal seeking