search for: cfi

I get some failing tests from compiler-rt. FAIL: cfi :: cross-dso/stats.cpp (30831 of 30893) ******************** TEST 'cfi :: cross-dso/stats.cpp' FAILED ******************** Script: -- /usr/local/google/home/prazek/llvm-build-release/./bin/clang -fuse-ld=gold -flto -fsanitize=cfi -fwhole-program-vtables --driver-mode=g++ -fsanitize-cfi-cros...

Hello, Nathan > or if it should be a configure test, which might be safer. Are there > any x86 platforms (other than apple) that don't need PLT-indirect calls? Yes, mingw. However just tweaking the define is not enough - we're not loading address of GOT into ebx before the call (on 32 bit ABIs) thus the call will be to nowhere. -- With best regards, Anton Korobeynikov Faculty of

...ionCallback(void); asm( ".text\n" ".align 8\n" ".globl " ASMPREFIX "X86CompilationCallback\n" + ".local .local_got_stub\n" TYPE_FUNCTION(X86CompilationCallback) ASMPREFIX "X86CompilationCallback:\n" CFI(".cfi_startproc\n") "pushl %ebp\n" + CFI(".cfi_def_cfa_offset 12\n") + CFI(".cfi_offset %ebp, -12\n") + "movl %esp, %ebp\n" // Standard prologue + CFI(".cfi_def_cfa_register %ebp\n") + "pushl %eax\n&quot...

...this out. A few comments below. > >> > >> On Mon, May 15, 2017 at 5:17 PM, Evgenii Stepanov via llvm-dev > >> <llvm-dev at lists.llvm.org> wrote: > >>> > >>> Hi, > >>> > >>> this is a proposal for the implementation of CFI-icall [1] with > ThinLTO. > >>> > >>> Jumptables are generated in the merged module. To generate a > >>> jumptable, we need a list of functions with !type annotations, > >>> including (in non-cross-dso mode) external functions. Unfortunately, >...

...urne <peter at pcc.me.uk> wrote: > Thanks for sending this out. A few comments below. > > On Mon, May 15, 2017 at 5:17 PM, Evgenii Stepanov via llvm-dev > <llvm-dev at lists.llvm.org> wrote: >> >> Hi, >> >> this is a proposal for the implementation of CFI-icall [1] with ThinLTO. >> >> Jumptables are generated in the merged module. To generate a >> jumptable, we need a list of functions with !type annotations, >> including (in non-cross-dso mode) external functions. Unfortunately, >> LLVM IR does not preserve unused fun...

There seem to be some recent regressions in clang/llvm. I see some test failing, and there is also this issue: https://llvm.org/bugs/show_bug.cgi?id=30466 Is anyone working on it? Piotr -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160920/ade5e8cd/attachment.html>

Hi, this is a proposal for the implementation of CFI-icall [1] with ThinLTO. Jumptables are generated in the merged module. To generate a jumptable, we need a list of functions with !type annotations, including (in non-cross-dso mode) external functions. Unfortunately, LLVM IR does not preserve unused function declarations, and we don’t want to cop...

We would also like to clarify on the misconceptions around CFI Instructions: There are two things that need to be clarified here: 1) Extra CFI FDE entries for basic blocks does not mean more dynamic instructions are executed. In fact, they do not increase at all. Krys talked about this earlier. 2) We do deduplication of common static CFI instructions in the...

I'm a bit confused by this subthread -- doesn't BOLT have the exact same CFI bloat issue? From my cursory reading of the propellor doc, the CFI duplication is _necessary_ to represent discontiguous functions, not anything particular to the way Propellor happens to generate those discontiguous functions. And emitting discontiguous functions is a fundamental goal of this, ri...

I want to create an experiment to show the effectiveness of cfi : For example , I first need a program with vulnerability so that we can hijack its control flow; then I enforce cfi of llvm and we can't hijack its control flow. Do you have any advice for me? - mudongliang -------------- next part -------------- An HTML attachment was scrubbed... URL:...

2015-09-01 11:38 GMT+08:00 John Criswell <jtcriswel at gmail.com>: > On 8/31/15 10:43 PM, 慕冬亮 via llvm-dev wrote: > > I want to create an experiment to show the effectiveness of cfi : > For example , > I first need a program with vulnerability so that we can hijack its > control flow; > > then I enforce cfi of llvm and we can't hijack its control flow. > > Do you have any advice for me? > > > The CFI implementation we updated to work with x86-...

Hi, I would like to propose extending the Control-Flow Integrity (CFI) mechanism in LLVM/Clang with a feature that allows users to explicitly link classes that have no inheritance link. Usually, if one class is used at locations in code where this class is not expected, this will create a CFI error at runtime, assuming the application is built with CFI enabled. Howev...

Hi all, I've encountered a couple of minor build issues on Solaris that have crept in since 2.5, fixes below: 1. In lib/Target/X86/X86JITInfo.cpp, there is: // Check if building with -fPIC #if defined(__PIC__) && __PIC__ && defined(__linux__) #define ASMCALLSUFFIX "@PLT" #else #define ASMCALLSUFFIX #endif Which causes a link failure due to the non-PLT

...y to >> make it more minimal. >> Were you expecting something like this? >> >> Also I think the tests that I should provide along with the patch should >> be in a special format right? >> > > Yes. Take a look at other tests in llvm/projects/compiler-rt/test/cfi > > (I did not study your patch or tests in detail yet, and probably won't > have time until mid Jul. But others may) > > My major concern with any such patch is that it complicates the > implementation. > For many parts of compiler extra complexity is acceptable, but CFI i...

...; (And in general, please try to provide tests with any patch) > > Thanks! > > --kcc > > > On Thu, Jun 15, 2017 at 5:08 AM, Enes Göktaş <enes.goktas at gmail.com> > wrote: > >> Hi, >> >> I would like to propose extending the Control-Flow Integrity (CFI) >> mechanism in LLVM/Clang with a feature that allows users to explicitly link >> classes that have no inheritance link. Usually, if one class is used at >> locations in code where this class is not expected, this will create a CFI >> error at runtime, assuming the applicat...

...sic blocks. > > We will re-prioritize and send out a patch to handle exception basic blocks. > > Thanks > Sri > > On Mon, Oct 7, 2019 at 11:15 AM Sriraman Tallam <tmsriram at google.com> wrote: > > > > We would also like to clarify on the misconceptions around CFI Instructions: > > > > There are two things that need to be clarified here: > > > > 1) Extra CFI FDE entries for basic blocks does not mean more dynamic > > instructions are executed. In fact, they do not increase at all. Krys > > talked about this earlier. >...

...ang 2015-09-02 0:58 GMT+08:00 Kostya Serebryany <kcc at google.com>: > Take a look at > > clang.llvm.org/docs/ControlFlowIntegrityDesign.html > clang.llvm.org/docs/ControlFlowIntegrity.html > > And the tests: > https://github.com/llvm-mirror/compiler-rt/tree/master/test/cfi > > On Mon, Aug 31, 2015 at 7:43 PM, 慕冬亮 via llvm-dev <llvm-dev at lists.llvm.org > > wrote: > >> I want to create an experiment to show the effectiveness of cfi : >> For example , >> I first need a program with vulnerability so that we can hijack its >> co...

Hi everyone, I've been working on control-flow integrity (CFI) techniques over LLVM, and I'd like to get feedback on these techniques and their potential usefulness as a part of LLVM. I'd like to submit some patches for this; I've implemented a version of it, and I've applied it to large, real-world programs like Chromium to see how well it ho...

...les are explicitly disabled (`-fno-unwind-tables`). It is a conservative patch since it decreases scheduling potential (due to smaller scheduling regions) for the non-debug case but fixes the bug of generating inconsistent assembly. Would you mind elaborating a bit on your proposals to delay/change CFI instruction insertion? In particular, it'd help to hear a bit about how CFI instructions are inserted today (is some of it done by CFIInstrInserter, and the rest by target-specific frame lowering code?). CFI instructions are inserted during target specific frame lowering, the CFIInstrInserter i...

...you expecting something like this? > >>> > >>> Also I think the tests that I should provide along with the patch should > >>> be in a special format right? > >> > >> > >> Yes. Take a look at other tests in llvm/projects/compiler-rt/test/cfi > >> > >> (I did not study your patch or tests in detail yet, and probably won't > >> have time until mid Jul. But others may) > >> > >> My major concern with any such patch is that it complicates the > >> implementation. > >> For m...