From d28159c025829fc70a295b727e32f899a9e0c7c5 Mon Sep 17 00:00:00 2001 From: Nick Terrell Date: Thu, 18 Jul 2019 18:49:40 -0700 Subject: [fuzz] Add LZ4 frame fuzzers * Round trip fuzzer * Compress fuzzer * Decompress fuzzer --- ossfuzz/Makefile | 10 ++++-- ossfuzz/compress_frame_fuzzer.c | 42 ++++++++++++++++++++++++ ossfuzz/decompress_frame_fuzzer.c | 67 +++++++++++++++++++++++++++++++++++++++ ossfuzz/lz4_helpers.c | 51 +++++++++++++++++++++++++++++ ossfuzz/lz4_helpers.h | 13 ++++++++ ossfuzz/round_trip_frame_fuzzer.c | 39 +++++++++++++++++++++++ 6 files changed, 219 insertions(+), 3 deletions(-) create mode 100644 ossfuzz/compress_frame_fuzzer.c create mode 100644 ossfuzz/decompress_frame_fuzzer.c create mode 100644 ossfuzz/lz4_helpers.c create mode 100644 ossfuzz/lz4_helpers.h create mode 100644 ossfuzz/round_trip_frame_fuzzer.c diff --git a/ossfuzz/Makefile b/ossfuzz/Makefile index 9974b81..6875eb6 100644 --- a/ossfuzz/Makefile +++ b/ossfuzz/Makefile @@ -33,7 +33,8 @@ DEBUGFLAGS = -g -DLZ4_DEBUG=$(DEBUGLEVEL) LZ4_CFLAGS = $(CFLAGS) $(DEBUGFLAGS) $(MOREFLAGS) LZ4_CXXFLAGS = $(CXXFLAGS) $(DEBUGFLAGS) $(MOREFLAGS) -LZ4_CPPFLAGS = $(CPPFLAGS) -I$(LZ4DIR) -DXXH_NAMESPACE=LZ4_ +LZ4_CPPFLAGS = $(CPPFLAGS) -I$(LZ4DIR) -DXXH_NAMESPACE=LZ4_ \ + -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION FUZZERS := \ compress_fuzzer \ @@ -41,7 +42,10 @@ FUZZERS := \ round_trip_fuzzer \ round_trip_stream_fuzzer \ compress_hc_fuzzer \ - round_trip_hc_fuzzer + round_trip_hc_fuzzer \ + compress_frame_fuzzer \ + round_trip_frame_fuzzer \ + decompress_frame_fuzzer all: $(FUZZERS) @@ -54,7 +58,7 @@ $(LZ4DIR)/liblz4.a: $(CC) -c $(LZ4_CFLAGS) $(LZ4_CPPFLAGS) $< -o $@ # Generic rule for generating fuzzers -%_fuzzer: %_fuzzer.o $(LZ4DIR)/liblz4.a +%_fuzzer: %_fuzzer.o lz4_helpers.o $(LZ4DIR)/liblz4.a # Compile the standalone code just in case. The OSS-Fuzz code might # override the LIB_FUZZING_ENGINE value to "-fsanitize=fuzzer" $(CC) -c $(LZ4_CFLAGS) $(LZ4_CPPFLAGS) standaloneengine.c -o standaloneengine.o diff --git a/ossfuzz/compress_frame_fuzzer.c b/ossfuzz/compress_frame_fuzzer.c new file mode 100644 index 0000000..75c609f --- /dev/null +++ b/ossfuzz/compress_frame_fuzzer.c @@ -0,0 +1,42 @@ +/** + * This fuzz target attempts to compress the fuzzed data with the simple + * compression function with an output buffer that may be too small to + * ensure that the compressor never crashes. + */ + +#include +#include +#include +#include + +#include "fuzz_helpers.h" +#include "lz4.h" +#include "lz4frame.h" +#include "lz4_helpers.h" + +int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) +{ + uint32_t seed = FUZZ_seed(&data, &size); + LZ4F_preferences_t const prefs = FUZZ_randomPreferences(&seed); + size_t const compressBound = LZ4F_compressFrameBound(size, &prefs); + size_t const dstCapacity = FUZZ_rand32(&seed, 0, compressBound); + char* const dst = (char*)malloc(dstCapacity); + char* const rt = (char*)malloc(size); + + FUZZ_ASSERT(dst); + FUZZ_ASSERT(rt); + + /* If compression succeeds it must round trip correctly. */ + size_t const dstSize = + LZ4F_compressFrame(dst, dstCapacity, data, size, &prefs); + if (!LZ4F_isError(dstSize)) { + size_t const rtSize = FUZZ_decompressFrame(rt, size, dst, dstSize); + FUZZ_ASSERT_MSG(rtSize == size, "Incorrect regenerated size"); + FUZZ_ASSERT_MSG(!memcmp(data, rt, size), "Corruption!"); + } + + free(dst); + free(rt); + + return 0; +} diff --git a/ossfuzz/decompress_frame_fuzzer.c b/ossfuzz/decompress_frame_fuzzer.c new file mode 100644 index 0000000..bda25b0 --- /dev/null +++ b/ossfuzz/decompress_frame_fuzzer.c @@ -0,0 +1,67 @@ +/** + * This fuzz target attempts to decompress the fuzzed data with the simple + * decompression function to ensure the decompressor never crashes. + */ + +#include +#include +#include +#include + +#include "fuzz_helpers.h" +#include "lz4.h" +#define LZ4F_STATIC_LINKING_ONLY +#include "lz4frame.h" +#include "lz4_helpers.h" + +static void decompress(LZ4F_dctx* dctx, void* dst, size_t dstCapacity, + const void* src, size_t srcSize, + const void* dict, size_t dictSize, + const LZ4F_decompressOptions_t* opts) +{ + LZ4F_resetDecompressionContext(dctx); + if (dictSize == 0) + LZ4F_decompress(dctx, dst, &dstCapacity, src, &srcSize, opts); + else + LZ4F_decompress_usingDict(dctx, dst, &dstCapacity, src, &srcSize, + dict, dictSize, opts); +} + +int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) +{ + + uint32_t seed = FUZZ_seed(&data, &size); + size_t const dstCapacity = FUZZ_rand32(&seed, 0, 4 * size); + size_t const largeDictSize = 64 * 1024; + size_t const dictSize = FUZZ_rand32(&seed, 0, largeDictSize); + char* const dst = (char*)malloc(dstCapacity); + char* const dict = (char*)malloc(dictSize); + LZ4F_decompressOptions_t opts; + LZ4F_dctx* dctx; + LZ4F_createDecompressionContext(&dctx, LZ4F_VERSION); + + FUZZ_ASSERT(dctx); + FUZZ_ASSERT(dst); + FUZZ_ASSERT(dict); + + /* Prepare the dictionary. The data doesn't matter for decompression. */ + memset(dict, 0, dictSize); + + + /* Decompress using multiple configurations. */ + memset(&opts, 0, sizeof(opts)); + opts.stableDst = 0; + decompress(dctx, dst, dstCapacity, data, size, NULL, 0, &opts); + opts.stableDst = 1; + decompress(dctx, dst, dstCapacity, data, size, NULL, 0, &opts); + opts.stableDst = 0; + decompress(dctx, dst, dstCapacity, data, size, dict, dictSize, &opts); + opts.stableDst = 1; + decompress(dctx, dst, dstCapacity, data, size, dict, dictSize, &opts); + + LZ4F_freeDecompressionContext(dctx); + free(dst); + free(dict); + + return 0; +} diff --git a/ossfuzz/lz4_helpers.c b/ossfuzz/lz4_helpers.c new file mode 100644 index 0000000..9471630 --- /dev/null +++ b/ossfuzz/lz4_helpers.c @@ -0,0 +1,51 @@ +#include "fuzz_helpers.h" +#include "lz4_helpers.h" +#include "lz4hc.h" + +LZ4F_frameInfo_t FUZZ_randomFrameInfo(uint32_t* seed) +{ + LZ4F_frameInfo_t info = LZ4F_INIT_FRAMEINFO; + info.blockSizeID = FUZZ_rand32(seed, LZ4F_max64KB - 1, LZ4F_max4MB); + if (info.blockSizeID < LZ4F_max64KB) { + info.blockSizeID = LZ4F_default; + } + info.blockMode = FUZZ_rand32(seed, LZ4F_blockLinked, LZ4F_blockIndependent); + info.contentChecksumFlag = FUZZ_rand32(seed, LZ4F_noContentChecksum, + LZ4F_contentChecksumEnabled); + info.blockChecksumFlag = FUZZ_rand32(seed, LZ4F_noBlockChecksum, + LZ4F_blockChecksumEnabled); + return info; +} + +LZ4F_preferences_t FUZZ_randomPreferences(uint32_t* seed) +{ + LZ4F_preferences_t prefs = LZ4F_INIT_PREFERENCES; + prefs.frameInfo = FUZZ_randomFrameInfo(seed); + prefs.compressionLevel = FUZZ_rand32(seed, 0, LZ4HC_CLEVEL_MAX + 3) - 3; + prefs.autoFlush = FUZZ_rand32(seed, 0, 1); + prefs.favorDecSpeed = FUZZ_rand32(seed, 0, 1); + return prefs; +} + +size_t FUZZ_decompressFrame(void* dst, const size_t dstCapacity, + const void* src, const size_t srcSize) +{ + LZ4F_decompressOptions_t opts; + memset(&opts, 0, sizeof(opts)); + opts.stableDst = 1; + LZ4F_dctx* dctx; + LZ4F_createDecompressionContext(&dctx, LZ4F_VERSION); + FUZZ_ASSERT(dctx); + + size_t dstSize = dstCapacity; + size_t srcConsumed = srcSize; + size_t const rc = + LZ4F_decompress(dctx, dst, &dstSize, src, &srcConsumed, &opts); + FUZZ_ASSERT(!LZ4F_isError(rc)); + FUZZ_ASSERT(rc == 0); + FUZZ_ASSERT(srcConsumed == srcSize); + + LZ4F_freeDecompressionContext(dctx); + + return dstSize; +} diff --git a/ossfuzz/lz4_helpers.h b/ossfuzz/lz4_helpers.h new file mode 100644 index 0000000..c99fb01 --- /dev/null +++ b/ossfuzz/lz4_helpers.h @@ -0,0 +1,13 @@ +#ifndef LZ4_HELPERS +#define LZ4_HELPERS + +#include "lz4frame.h" + +LZ4F_frameInfo_t FUZZ_randomFrameInfo(uint32_t* seed); + +LZ4F_preferences_t FUZZ_randomPreferences(uint32_t* seed); + +size_t FUZZ_decompressFrame(void* dst, const size_t dstCapacity, + const void* src, const size_t srcSize); + +#endif /* LZ4_HELPERS */ diff --git a/ossfuzz/round_trip_frame_fuzzer.c b/ossfuzz/round_trip_frame_fuzzer.c new file mode 100644 index 0000000..1eea90c --- /dev/null +++ b/ossfuzz/round_trip_frame_fuzzer.c @@ -0,0 +1,39 @@ +/** + * This fuzz target performs a lz4 round-trip test (compress & decompress), + * compares the result with the original, and calls abort() on corruption. + */ + +#include +#include +#include +#include + +#include "fuzz_helpers.h" +#include "lz4.h" +#include "lz4frame.h" +#include "lz4_helpers.h" + +int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) +{ + uint32_t seed = FUZZ_seed(&data, &size); + LZ4F_preferences_t const prefs = FUZZ_randomPreferences(&seed); + size_t const dstCapacity = LZ4F_compressFrameBound(size, &prefs); + char* const dst = (char*)malloc(dstCapacity); + char* const rt = (char*)malloc(size); + + FUZZ_ASSERT(dst); + FUZZ_ASSERT(rt); + + /* Compression must succeed and round trip correctly. */ + size_t const dstSize = + LZ4F_compressFrame(dst, dstCapacity, data, size, &prefs); + FUZZ_ASSERT(!LZ4F_isError(dstSize)); + size_t const rtSize = FUZZ_decompressFrame(rt, size, dst, dstSize); + FUZZ_ASSERT_MSG(rtSize == size, "Incorrect regenerated size"); + FUZZ_ASSERT_MSG(!memcmp(data, rt, size), "Corruption!"); + + free(dst); + free(rt); + + return 0; +} -- cgit v0.12