similar to: [RFC] Using segmentation to harden SafeStack

Hi, I previously posted about using 32-bit X86 segmentation to harden SafeStack: http://lists.llvm.org/pipermail/llvm-dev/2016-May/100346.html That involves lowering the limits of the DS and ES segments that are used for ordinary data accesses while leaving the limit for SS, the stack segment, set to its maximum value. The safe stacks were clustered above the limits of DS and ES. Thus, by

On 2/7/2017 20:02, Kostya Serebryany wrote: > ... > > My understanding is that BNDCU is the cheapest possible instruction, > just like XOR or ADD, > so the overhead should be relatively small. > Still my guesstimate would be >= 5% since stores are very numerous. > And such overhead will be on top of whatever overhead SafeStack has. > Do you have any measurements to

Hi, I would like to use SafeStack sanitize option on ARM platform. Since Linux libc does not implement such functionality (in opposite to FreeBSD or Android), I need to use SafeStack compiler RT library. Unfortunately I've noticed that libclang_rt.safestack is not compiled/built for ARM platform. Looking into cmake file: "set(ALL_SAFESTACK_SUPPORTED_ARCH ${X86} ${X86_64} ${ARM64}

Hi Kostya, >On Wed, Nov 12, 2014 at 2:50 AM, Volodymyr Kuznetsov <vova.kuznetsov at epfl.ch >> wrote: > >> Dear LLVM developers, >> >> We've applied the feedback we received on Phabricator on the SafeStack >> patches, >> > >Did you investigate the possibility of moving the transformation from >codegen to the LLVM level, i.e. the same level

+nlewycky On Mon, Nov 17, 2014 at 9:36 AM, Volodymyr Kuznetsov <vova.kuznetsov at epfl.ch > wrote: > Hi Kostya, > > On Sat, Nov 15, 2014 at 1:53 PM, Volodymyr Kuznetsov < > vova.kuznetsov at epfl.ch> wrote: > > Do you think moving the pass to lib/Transform/Instrumentation but > > scheduling it during code generation would make sense ? If so, we'll >

Hi all, Shouldn't SafeStack pass be executed only if the target has TLS support? E.g. currently for NVPTX there is no way to implement `__safestack_unsafe_stack_ptr`. Any comments? Thanks, Samuel -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150623/53f40bea/attachment.html>

On 12/28/18 10:09 PM, Leonard Chan via llvm-dev wrote: > Hello, > > I'm in the process of creating a pass for the new PM for SafeStack > which is only available as a part of the legacy PM. The only thing > bugging me is in regards to the TargetPassConfig analysis. Whereas > most other passes/analyses I have seen separate the logic between the > actual pass and anything it

Hello, I'm in the process of creating a pass for the new PM for SafeStack which is only available as a part of the legacy PM. The only thing bugging me is in regards to the TargetPassConfig analysis. Whereas most other passes/analyses I have seen separate the logic between the actual pass and anything it does to the IRUnits it runs over are in 2 separate classes, TargetPassConfig has them

Dear LLVM developers, Our team has developed an LLVM-based protection mechanism that (i) prevents control-flow hijack attacks enabled by memory corruption errors and (ii) has very low performance overhead. We would like to contribute the implementation to LLVM. We presented this work at the OSDI 2014 conference, at several software companies, and several US universities. We received positive

I'm noticing the X86InstrInfo::GetInstSizeInBytes() function returning incorrect sizes for some instructions. I looked through the llvm-dev archives and noticed that a patch was submitted once in April 2009 for instruction length calculation on amd-64. I'm using Intel Core 2 Duo (64 bit) so maybe there is a similar issue? I don't have another computer I can test this on to see if

Hello, I'm trying to write some backends for LLVM that generate code that complies with SFI validation rules by re-implementing SFI for the LLVM x86 backend based on the Google NaCl project. However, in trying to implement 32-byte code alignment, X86InstrInfo::GetInstSizeInBytes() is returning incorrect instruction sizes for certain instructions (that I have seen so far): MOV32mi,

Approved. On Wed, Mar 23, 2016 at 5:11 AM, Mohit Bhakkad <mohit.bhakkad at gmail.com> wrote: > Hi Peter, > > Request you to approve the merger of this patch to 3.8.1 branch: > > http://reviews.llvm.org/rL262690 > > Thanks, > Mohit > -- -- Peter -------------- next part -------------- An HTML attachment was scrubbed... URL:

On 4 Nov 2014, at 00:36, Kostya Serebryany <kcc at google.com> wrote: > You at least increase the memory footprint by doubling the stack sizes. Not quite. The space overhead is constant for each stack frame - you just need to keep track of the top of two stacks, rather than one. The important overhead is that you reduce locality of reference. You will need a minimum of two cache

Hi, I am using clang++3.9 to build a simple program with both CFI and safe-stack. I am getting linker errors when combining -fsanitize=safe-stack, -fsanitize=cfi, and -fno-sanitize-trap=all. Combining safe-stack and CFI without -fno-sanitize-trap=all works as expected. It looks like clang is attempting to link in two compiler-rt libraries, one for ubsan and one for safestack, and this causes

Hallo, I worked on how to handle the distinction between variadic defines and uses and my current solution is this: I introduce a new dag item in Instruction called VariadicOperandList, which by default is undefined. It keeps a marker variable_* and all operands which are placeholders for variable lists (like 'reglist' on ARM). I think it's the cleanest solution to keep them in a

On 8 Oct 2014, at 18:19, Reid Kleckner <rnk at google.com> wrote: > The one target I know about where varargs are passed differently from normal arguments is aarch64-apple-ios/macosx. After thinking a bit more, I think this forwarding thunk representation works fine even on that target. Typically a forwarding thunk is called indirectly, or at least through a bitcast, so the LLVM IR call

The Wine development release 2.21 is now available. What's new in this release (see below for details): - Still more metafile support in GdiPlus. - Indirect draws support in Direct 3D. - Calling convention fixes on ARM. - Improved serial port detection on Linux. - Services fixes on WoW64. - Better DPI scaling in the Shell Explorer. - Various bug fixes. The source is available

Am Mittwoch, 26. September 2012, 11:18:20 schrieb Jakob Stoklund Olesen: > Hi Christoph, > > As you noticed, MCInstrDesc doesn't distinguish between variadic uses and > defs. Since variadic instructions will always require some kind of special > handling, it doesn't seem worthwhile to make the model more detailed. I don't see what makes them so different from other

On Thu, Sep 7, 2017 at 9:46 AM, David Blaikie <dblaikie at gmail.com> wrote: > Feels to me like bugs rather than inconsistencies (I'd think of an > inconsistency as "we do X over here intentionally and Y over here > intentionally but they're in contradiction to one another") > The DBG_VALUE MachineInstr actually already has a way to indicate that the computed

On Sep 24, 2012, at 6:39 PM, Christoph Grenz <christophg+llvm at grenz-bonn.de> wrote: > Is it possible to extend LLVM to check if 'variable_ops' is in 'ins' and/or > 'outs' in tablegen, so that MCInstrDesc could provide something like > hasVariadicDefs() and hasVariadicUses()? > > That way handling variadic instructions when disassembling would be