| 1 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 2 | // See https://llvm.org/LICENSE.txt for license information. |
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| 3 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 4 | |
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| 5 | // Triggers the bug described here: |
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| 6 | // https://github.com/google/oss-fuzz/issues/4605 |
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| 7 | // |
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| 8 | // Tests that custom mutators do not cause MSan false positives. We are careful |
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| 9 | // to use every parameter to ensure none cause false positives. |
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| 10 | |
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| 11 | #include <algorithm> |
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| 12 | #include <cstddef> |
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| 13 | #include <cstdint> |
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| 14 | #include <cstdio> |
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| 15 | #include <cstring> |
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| 16 | |
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| 17 | extern "C" { |
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| 18 | |
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| 19 | int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) { return 0; } |
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| 20 | |
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| 21 | size_t LLVMFuzzerCustomMutator(uint8_t *Data, size_t Size, size_t MaxSize, |
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| 22 | unsigned int Seed) { |
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| 23 | if (Seed == 7) |
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| 24 | return 0; |
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| 25 | if (MaxSize == 0) |
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| 26 | return 0; |
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| 27 | for (size_t I = 0; I < Size; ++I) { |
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| 28 | if (Data[I] == 42) { |
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| 29 | printf(format: "BINGO\n" ); |
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| 30 | } |
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| 31 | } |
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| 32 | return Size; |
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| 33 | } |
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| 34 | |
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| 35 | size_t LLVMFuzzerCustomCrossOver( |
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| 36 | const uint8_t *Data1, size_t Size1, const uint8_t *Data2, size_t Size2, |
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| 37 | uint8_t *Out, size_t MaxOutSize, unsigned int Seed) { |
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| 38 | if (Seed == 7) |
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| 39 | return 0; |
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| 40 | size_t I = 0; |
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| 41 | for (; I < Size1 && I < Size2 && I < MaxOutSize; ++I) { |
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| 42 | Out[I] = std::min(a: Data1[I], b: Data2[I]); |
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| 43 | } |
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| 44 | return I; |
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| 45 | } |
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| 46 | |
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| 47 | } // extern "C" |
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| 48 | |
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