[PATCH] D91410: [llvm][clang][mlir] Add checks for the return values from Target::createXXX to prevent protential null deref

[Ella Ma via Phabricator via cfe-commits]

OikawaKirie created this revision.
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All these potential null pointer dereferences are reported by my static analyzer for null smart pointer dereferences, which has a different implementation from `alpha.cplusplus.SmartPtr`.

The checked pointers in this patch are initialized by Target::createXXX functions. When the creator function pointer is not correctly set, a null pointer will be returned, or the creator function may originally return a null pointer.

Some of them may not make sense as they may be checked before entering the function, but I fixed them all in this patch. I submit this fix because 1) similar checks are found in some other places in the LLVM codebase for the same return value of the function; and, 2) some of the pointers are dereferenced before they are checked, which may definitely trigger a null pointer dereference if the return value is nullptr.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D91410

Files:
  clang/tools/clang-fuzzer/handle-llvm/handle_llvm.cpp
  clang/tools/driver/cc1as_main.cpp
  llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
  llvm/lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp
  llvm/lib/CodeGen/LLVMTargetMachine.cpp
  llvm/lib/CodeGen/ParallelCG.cpp
  llvm/lib/LTO/LTOBackend.cpp
  llvm/lib/LTO/LTOCodeGenerator.cpp
  llvm/lib/LTO/LTOModule.cpp
  llvm/lib/LTO/ThinLTOCodeGenerator.cpp
  llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
  llvm/tools/llvm-exegesis/lib/LlvmState.cpp
  llvm/tools/llvm-exegesis/llvm-exegesis.cpp
  llvm/tools/llvm-mc/llvm-mc.cpp
  llvm/tools/llvm-mca/llvm-mca.cpp
  llvm/tools/llvm-ml/llvm-ml.cpp
  llvm/tools/llvm-objdump/MachODump.cpp
  llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
  mlir/lib/Conversion/GPUCommon/ConvertKernelFuncToBlob.cpp
  mlir/lib/ExecutionEngine/ExecutionEngine.cpp

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