1 files changed, 134 insertions, 0 deletions
diff --git a/ossfuzz/round_trip_frame_uncompressed_fuzzer.c b/ossfuzz/round_trip_frame_uncompressed_fuzzer.c
new file mode 100644
index 0000000..76a99d2
--- /dev/null
+++ b/ossfuzz/round_trip_frame_uncompressed_fuzzer.c
@@ -0,0 +1,134 @@
+/**
+ * This fuzz target performs a lz4 round-trip test (compress & decompress),
+ * compares the result with the original, and calls abort() on corruption.
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "fuzz_data_producer.h"
+#include "fuzz_helpers.h"
+#include "lz4.h"
+#include "lz4_helpers.h"
+#include "lz4frame.h"
+#include "lz4frame_static.h"
+
+static void decompress(LZ4F_dctx *dctx, void *src, void *dst,
+                       size_t dstCapacity, size_t readSize) {
+    size_t ret = 1;
+    const void *srcPtr = (const char *) src;
+    void *dstPtr = (char *) dst;
+    const void *const srcEnd = (const char *) srcPtr + readSize;
+
+    while (ret != 0) {
+        while (srcPtr < srcEnd && ret != 0) {
+            /* Any data within dst has been flushed at this stage */
+            size_t dstSize = dstCapacity;
+            size_t srcSize = (const char *) srcEnd - (const char *) srcPtr;
+            ret = LZ4F_decompress(dctx, dstPtr, &dstSize, srcPtr, &srcSize,
+                    /* LZ4F_decompressOptions_t */ NULL);
+            FUZZ_ASSERT(!LZ4F_isError(ret));
+
+            /* Update input */
+            srcPtr = (const char *) srcPtr + srcSize;
+            dstPtr = (char *) dstPtr + dstSize;
+        }
+
+        FUZZ_ASSERT(srcPtr <= srcEnd);
+    }
+}
+
+static void compress_round_trip(const uint8_t *data, size_t size,
+                                FUZZ_dataProducer_t *producer, LZ4F_preferences_t const prefs) {
+
+    // Choose random uncompressed offset start and end by producing seeds from random data, calculate the remaining
+    // data size that will be used for compression later and use the seeds to actually calculate the offsets
+    size_t const uncompressedOffsetSeed = FUZZ_dataProducer_retrieve32(producer);
+    size_t const uncompressedEndOffsetSeed = FUZZ_dataProducer_retrieve32(producer);
+    size = FUZZ_dataProducer_remainingBytes(producer);
+
+    size_t const uncompressedOffset = FUZZ_getRange_from_uint32(uncompressedOffsetSeed, 0, size);
+    size_t const uncompressedEndOffset = FUZZ_getRange_from_uint32(uncompressedEndOffsetSeed, uncompressedOffset, size);
+    size_t const uncompressedSize = uncompressedEndOffset - uncompressedOffset;
+    FUZZ_ASSERT(uncompressedOffset <= uncompressedEndOffset);
+    FUZZ_ASSERT(uncompressedEndOffset <= size);
+
+    const uint8_t *const uncompressedData = data + uncompressedOffset;
+
+    size_t const dstCapacity =
+            LZ4F_compressFrameBound(LZ4_compressBound(size), &prefs) +
+            uncompressedSize;
+    char *const dst = (char *) malloc(dstCapacity);
+    size_t rtCapacity = dstCapacity;
+    char *const rt = (char *) malloc(rtCapacity);
+
+    FUZZ_ASSERT(dst);
+    FUZZ_ASSERT(rt);
+
+    /* Compression must succeed and round trip correctly. */
+    LZ4F_compressionContext_t ctx;
+    size_t const ctxCreation = LZ4F_createCompressionContext(&ctx, LZ4F_VERSION);
+    FUZZ_ASSERT(!LZ4F_isError(ctxCreation));
+
+    size_t const headerSize = LZ4F_compressBegin(ctx, dst, dstCapacity, &prefs);
+    FUZZ_ASSERT(!LZ4F_isError(headerSize));
+    size_t compressedSize = headerSize;
+
+    /* Compress data before uncompressed offset */
+    size_t lz4Return = LZ4F_compressUpdate(ctx, dst + compressedSize, dstCapacity,
+                                           data, uncompressedOffset, NULL);
+    FUZZ_ASSERT(!LZ4F_isError(lz4Return));
+    compressedSize += lz4Return;
+
+    /* Add uncompressed data */
+    lz4Return = LZ4F_uncompressedUpdate(ctx, dst + compressedSize, dstCapacity,
+                                        uncompressedData, uncompressedSize, NULL);
+    FUZZ_ASSERT(!LZ4F_isError(lz4Return));
+    compressedSize += lz4Return;
+
+    /* Compress data after uncompressed offset */
+    lz4Return = LZ4F_compressUpdate(ctx, dst + compressedSize, dstCapacity,
+                                    data + uncompressedEndOffset,
+                                    size - uncompressedEndOffset, NULL);
+    FUZZ_ASSERT(!LZ4F_isError(lz4Return));
+    compressedSize += lz4Return;
+
+    /* Finish compression */
+    lz4Return = LZ4F_compressEnd(ctx, dst + compressedSize, dstCapacity, NULL);
+    FUZZ_ASSERT(!LZ4F_isError(lz4Return));
+    compressedSize += lz4Return;
+
+    LZ4F_decompressOptions_t opts;
+    memset(&opts, 0, sizeof(opts));
+    opts.stableDst = 1;
+    LZ4F_dctx *dctx;
+    LZ4F_createDecompressionContext(&dctx, LZ4F_VERSION);
+    FUZZ_ASSERT(dctx);
+
+    decompress(dctx, dst, rt, rtCapacity, compressedSize);
+
+    LZ4F_freeDecompressionContext(dctx);
+
+    FUZZ_ASSERT_MSG(!memcmp(data, rt, size), "Corruption!");
+
+    free(dst);
+    free(rt);
+
+    FUZZ_dataProducer_free(producer);
+    LZ4F_freeCompressionContext(ctx);
+}
+
+static void compress_independent_block_mode(const uint8_t *data, size_t size) {
+    FUZZ_dataProducer_t *producer = FUZZ_dataProducer_create(data, size);
+    LZ4F_preferences_t prefs = FUZZ_dataProducer_preferences(producer);
+    prefs.frameInfo.blockMode = LZ4F_blockIndependent;
+    compress_round_trip(data, size, producer, prefs);
+}
+
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+    compress_independent_block_mode(data, size);
+    return 0;
+}