[tor-bugs] #23357 [Core Tor/Tor]: Build with non-Cross-DSO CFI

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#23357: Build with non-Cross-DSO CFI
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     Reporter:  shawn.webb    |      Owner:  (none)
         Type:  enhancement   |     Status:  new
     Priority:  Medium        |  Milestone:
    Component:  Core Tor/Tor  |    Version:
     Severity:  Normal        |   Keywords:
Actual Points:                |  Parent ID:
       Points:                |   Reviewer:
      Sponsor:                |
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 Control Flow Integrity is an exploit mitigation. clang/llvm has a CFI
 implementation that can be used on hardened operating systems like
 HardenedBSD.

 When lld is the compiler, non-Cross-DSO CFI from clang/llvm can be used.
 I've tested this on HardenedBSD with a very basic configuration.

 Attached is a candidate patch for enabling non-Cross-DSO CFI for the core
 Tor application.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23357>
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