fixed zstdmt corruption issue when enabling overlapped sections

see Asana board for detailed explanation on why and how to fix it
dev
Yann Collet 2017-01-25 16:25:38 -08:00
parent 943cff9c37
commit bb0027405a
6 changed files with 46 additions and 18 deletions

View File

@ -60,7 +60,8 @@ struct ZSTD_CCtx_s {
U32 nextToUpdate; /* index from which to continue dictionary update */
U32 nextToUpdate3; /* index from which to continue dictionary update */
U32 hashLog3; /* dispatch table : larger == faster, more memory */
U32 loadedDictEnd;
U32 loadedDictEnd; /* index of end of dictionary */
U32 forceWindow; /* force back-references to respect limit of 1<<wLog, even for dictionary */
ZSTD_compressionStage_e stage;
U32 rep[ZSTD_REP_NUM];
U32 repToConfirm[ZSTD_REP_NUM];
@ -100,7 +101,7 @@ ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem)
cctx = (ZSTD_CCtx*) ZSTD_malloc(sizeof(ZSTD_CCtx), customMem);
if (!cctx) return NULL;
memset(cctx, 0, sizeof(ZSTD_CCtx));
memcpy(&(cctx->customMem), &customMem, sizeof(customMem));
cctx->customMem = customMem;
return cctx;
}
@ -118,6 +119,15 @@ size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx)
return sizeof(*cctx) + cctx->workSpaceSize;
}
size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value)
{
switch(param)
{
case ZSTD_p_forceWindow : cctx->forceWindow = value; return 0;
default: return ERROR(parameter_unknown);
}
}
const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx) /* hidden interface */
{
return &(ctx->seqStore);
@ -748,6 +758,13 @@ _check_compressibility:
}
#if 0 /* for debug */
# define STORESEQ_DEBUG
#include <stdio.h> /* fprintf */
U32 g_startDebug = 0;
const BYTE* g_start = NULL;
#endif
/*! ZSTD_storeSeq() :
Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
`offsetCode` : distance to match, or 0 == repCode.
@ -755,13 +772,14 @@ _check_compressibility:
*/
MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const void* literals, U32 offsetCode, size_t matchCode)
{
#if 0 /* for debug */
static const BYTE* g_start = NULL;
const U32 pos = (U32)((const BYTE*)literals - g_start);
if (g_start==NULL) g_start = (const BYTE*)literals;
//if ((pos > 1) && (pos < 50000))
printf("Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
#ifdef STORESEQ_DEBUG
if (g_startDebug) {
const U32 pos = (U32)((const BYTE*)literals - g_start);
if (g_start==NULL) g_start = (const BYTE*)literals;
if ((pos > 1895000) && (pos < 1895300))
fprintf(stderr, "Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
}
#endif
/* copy Literals */
ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
@ -2305,7 +2323,7 @@ static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
else cctx->nextToUpdate -= correction;
}
if ((U32)(ip+blockSize - cctx->base) > cctx->loadedDictEnd + maxDist) {
if ((U32)(ip+blockSize - cctx->base) > (cctx->forceWindow ? 0 : cctx->loadedDictEnd) + maxDist) {
/* enforce maxDist */
U32 const newLowLimit = (U32)(ip+blockSize - cctx->base) - maxDist;
if (cctx->lowLimit < newLowLimit) cctx->lowLimit = newLowLimit;

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@ -238,6 +238,7 @@ void ZSTDMT_compressChunk(void* jobDescription)
} else {
size_t const initError = ZSTD_compressBegin_advanced(job->cctx, job->srcStart, job->dictSize, job->params, job->fullFrameSize);
if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
ZSTD_setCCtxParameter(job->cctx, ZSTD_p_forceWindow, 1);
}
if (!job->firstChunk) { /* flush frame header */
size_t const hSize = ZSTD_compressContinue(job->cctx, dstBuff.start, dstBuff.size, src, 0);

View File

@ -1973,7 +1973,7 @@ size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds,
switch(paramType)
{
default : return ERROR(parameter_unknown);
case ZSTDdsp_maxWindowSize : zds->maxWindowSize = paramValue ? paramValue : (U32)(-1); break;
case DStream_p_maxWindowSize : zds->maxWindowSize = paramValue ? paramValue : (U32)(-1); break;
}
return 0;
}

View File

@ -401,6 +401,12 @@ ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem);
* Gives the amount of memory used by a given ZSTD_CCtx */
ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
/*! ZSTD_setCCtxParameter() :
* Set advanced parameters, selected through enum ZSTD_CCtxParameter
* @result : 0, or an error code (which can be tested with ZSTD_isError()) */
typedef enum { ZSTD_p_forceWindow } ZSTD_CCtxParameter;
size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value);
/*! ZSTD_createCDict_byReference() :
* Create a digested dictionary for compression
* Dictionary content is simply referenced, and therefore stays in dictBuffer.
@ -519,7 +525,7 @@ ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
/*===== Advanced Streaming decompression functions =====*/
typedef enum { ZSTDdsp_maxWindowSize } ZSTD_DStreamParameter_e;
typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem);
ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
ZSTDLIB_API size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue);

View File

@ -530,7 +530,7 @@ static dRess_t FIO_createDResources(const char* dictFileName)
/* Allocation */
ress.dctx = ZSTD_createDStream();
if (ress.dctx==NULL) EXM_THROW(60, "Can't create ZSTD_DStream");
ZSTD_setDStreamParameter(ress.dctx, ZSTDdsp_maxWindowSize, g_memLimit);
ZSTD_setDStreamParameter(ress.dctx, DStream_p_maxWindowSize, g_memLimit);
ress.srcBufferSize = ZSTD_DStreamInSize();
ress.srcBuffer = malloc(ress.srcBufferSize);
ress.dstBufferSize = ZSTD_DStreamOutSize();

View File

@ -225,7 +225,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
inBuff2 = inBuff;
DISPLAYLEVEL(3, "test%3i : decompress %u bytes : ", testNb++, COMPRESSIBLE_NOISE_LENGTH);
ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
{ size_t const r = ZSTD_setDStreamParameter(zd, ZSTDdsp_maxWindowSize, 1000000000); /* large limit */
{ size_t const r = ZSTD_setDStreamParameter(zd, DStream_p_maxWindowSize, 1000000000); /* large limit */
if (ZSTD_isError(r)) goto _output_error; }
{ size_t const remaining = ZSTD_decompressStream(zd, &outBuff, &inBuff);
if (remaining != 0) goto _output_error; } /* should reach end of frame == 0; otherwise, some data left, or an error */
@ -426,7 +426,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
/* Memory restriction */
DISPLAYLEVEL(3, "test%3i : maxWindowSize < frame requirement : ", testNb++);
ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
{ size_t const r = ZSTD_setDStreamParameter(zd, ZSTDdsp_maxWindowSize, 1000); /* too small limit */
{ size_t const r = ZSTD_setDStreamParameter(zd, DStream_p_maxWindowSize, 1000); /* too small limit */
if (ZSTD_isError(r)) goto _output_error; }
inBuff.src = compressedBuffer;
inBuff.size = cSize;
@ -466,6 +466,10 @@ static size_t findDiff(const void* buf1, const void* buf2, size_t max)
if (b1[u] != b2[u]) break;
}
DISPLAY("Error at position %u / %u \n", (U32)u, (U32)max);
DISPLAY(" %02X %02X %02X :%02X: %02X %02X %02X %02X %02X \n",
b1[u-3], b1[u-2], b1[u-1], b1[u-0], b1[u+1], b1[u+2], b1[u+3], b1[u+4], b1[u+5]);
DISPLAY(" %02X %02X %02X :%02X: %02X %02X %02X %02X %02X \n",
b2[u-3], b2[u-2], b2[u-1], b2[u-0], b2[u+1], b2[u+2], b2[u+3], b2[u+4], b2[u+5]);
return u;
}
@ -902,9 +906,8 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
decompressionResult = ZSTD_decompressStream(zd, &outBuff, &inBuff);
CHECK (ZSTD_isError(decompressionResult), "decompression error : %s", ZSTD_getErrorName(decompressionResult));
}
CHECK (decompressionResult != 0, "frame not fully decoded");
CHECK (outBuff.pos != totalTestSize, "decompressed data : wrong size")
CHECK (inBuff.pos != cSize, "compressed data should be fully read")
CHECK (outBuff.pos != totalTestSize, "decompressed data : wrong size (%u != %u)", (U32)outBuff.pos, (U32)totalTestSize);
CHECK (inBuff.pos != cSize, "compressed data should be fully read (%u != %u)", (U32)inBuff.pos, (U32)cSize);
{ U64 const crcDest = XXH64(dstBuffer, totalTestSize, 0);
if (crcDest!=crcOrig) findDiff(copyBuffer, dstBuffer, totalTestSize);
CHECK (crcDest!=crcOrig, "decompressed data corrupted");