compiler-rt/tools/gwp_asan/stack_trace_compressor_fuzzer.cpp

   1 #include <cstddef>
   2 #include <cstdint>
   3 #include <cstdio>
   4 #include <cstdlib>
   5 #include <vector>
   6
   7 #include "gwp_asan/stack_trace_compressor.h"
   8
   9 constexpr size_t kBytesForLargestVarInt = (sizeof(uintptr_t) * 8) / 7 + 1;
  10
  11 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
  12   size_t BufferSize = kBytesForLargestVarInt * Size / sizeof(uintptr_t);
  13   std::vector<uint8_t> Buffer(BufferSize);
  14   std::vector<uint8_t> Buffer2(BufferSize);
  15
  16   // Unpack the fuzz bytes.
  17   gwp_asan::compression::unpack(Data, Size,
  18                                 reinterpret_cast<uintptr_t *>(Buffer2.data()),
  19                                 BufferSize / sizeof(uintptr_t));
  20
  21   // Pack the fuzz bytes.
  22   size_t BytesWritten = gwp_asan::compression::pack(
  23       reinterpret_cast<const uintptr_t *>(Data), Size / sizeof(uintptr_t),
  24       Buffer.data(), BufferSize);
  25
  26   // Unpack the compressed buffer.
  27   size_t DecodedElements = gwp_asan::compression::unpack(
  28       Buffer.data(), BytesWritten,
  29       reinterpret_cast<uintptr_t *>(Buffer2.data()),
  30       BufferSize / sizeof(uintptr_t));
  31
  32   // Ensure that every element was encoded and decoded properly.
  33   if (DecodedElements != Size / sizeof(uintptr_t))
  34     abort();
  35
  36   // Ensure that the compression and uncompression resulted in the same trace.
  37   const uintptr_t *FuzzPtrs = reinterpret_cast<const uintptr_t *>(Data);
  38   const uintptr_t *DecodedPtrs =
  39       reinterpret_cast<const uintptr_t *>(Buffer2.data());
  40   for (size_t i = 0; i < Size / sizeof(uintptr_t); ++i) {
  41     if (FuzzPtrs[i] != DecodedPtrs[i]) {
  42       fprintf(stderr, "FuzzPtrs[%zu] != DecodedPtrs[%zu] (0x%zx vs. 0x%zx)", i,
  43               i, FuzzPtrs[i], DecodedPtrs[i]);
  44       abort();
  45     }
  46   }
  47
  48   return 0;
  49 }