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Subject: Re: [RFC] Support for segmentation-hardened SafeStack
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* LeMay, Michael <michael.lemay@intel.com> [2016-09-22 23:00:45 +0000]:
> I submitted several patches to LLVM and Clang to harden SafeStack using segmentation on x86-32 [1].  See [2] for general background on SafeStack.
...
> [1] http://lists.llvm.org/pipermail/llvm-dev/2016-May/100346.html
> [2] http://clang.llvm.org/docs/SafeStack.html

is all runtime support in the libc with your patches?
(i.e. no static linked interposition code from compiler-rt)

can you call into non-instrumented code?
(as Rich noted this looks like a new abi on i386)
i assume the segmented variant breaks abi while the
non-segmented one does not.

what is the unsafe stack size of the main thread?
how much is the resource usage overhead?

what happens if unsafe stack allocation fails?
how does the stack get deallocated at thread exit?
i assume they are consistent with normal stack
handling if this is done in musl.. except for the
main thread.

can signal handlers work with sigaltstack?