[PATCH] D76458: Add Indirect Thunk Support to X86 to mitigate Load Value Injection (LVI) [by modifying X86RetpolineThunks.cpp]

[Zola Bridges via Phabricator via cfe-commits]

zbrid added a comment.

I commented on the other patch about this before I saw this patch. Thanks for putting this up!

I think it looks pretty good, but could you do a more full refactor of the retpolinethunks pass in an NFC patch? Then have the LVI functionality added on top of that refactored patch?

S



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Comment at: llvm/lib/Target/X86/X86Subtarget.h:870
   bool enableIndirectBrExpand() const override {
-    return useRetpolineIndirectBranches();
+    return useRetpolineIndirectBranches() || useLVIControlFlowIntegrity();
   }
----------------
Probably can be changed to checking whether we are using indirect branch thunking, etc. I think there were a few other conditionals relating to retpolines that may also need to be changed. The renaming you did in the first indirect branch pass for some functions (ef EmitLoweredRetpoline -> EmitLoweredThunk) should perhaps also be preserved in whatever update you do.


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  https://reviews.llvm.org/D76458/new/

https://reviews.llvm.org/D76458