ddidderr/zstd-rs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Disallow Too-Long Repcodes When Using an Attached Dict

Browse Source
This commit is contained in:
W. Felix Handte
2018-06-13 14:58:36 -04:00
parent c14db94450
commit f74c2cd673
1 changed files with 20 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/compress/zstd_lazy.c
+20 -2
View File
@@ -503,15 +503,33 @@ size_t ZSTD_compressBlock_lazy_generic(
(searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS); (searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS);
U32 offset_1 = rep[0], offset_2 = rep[1], savedOffset=0; U32 offset_1 = rep[0], offset_2 = rep[1], savedOffset=0;
const ZSTD_matchState_t* const dms = ms->dictMatchState;
const U32 dictLowestIndex = dictMode == ZSTD_dictMatchState ?
dms->window.dictLimit : 0;
const BYTE* const dictBase = dictMode == ZSTD_dictMatchState ?
dms->window.base : NULL;
const BYTE* const dictLowest = dictMode == ZSTD_dictMatchState ?
dictBase + dictLowestIndex : NULL;
const BYTE* const dictEnd = dictMode == ZSTD_dictMatchState ?
dms->window.nextSrc : NULL;
const U32 dictAndPrefixLength = (U32)(ip - prefixLowest + dictEnd - dictLowest);
(void)dictMode; (void)dictMode;
/* init */ /* init */
ip += (ip==prefixLowest); ip += (dictAndPrefixLength == 0);
ms->nextToUpdate3 = ms->nextToUpdate; ms->nextToUpdate3 = ms->nextToUpdate;
{ U32 const maxRep = (U32)(ip-prefixLowest); if (dictMode == ZSTD_noDict) {
U32 const maxRep = (U32)(ip - prefixLowest);
if (offset_2 > maxRep) savedOffset = offset_2, offset_2 = 0; if (offset_2 > maxRep) savedOffset = offset_2, offset_2 = 0;
if (offset_1 > maxRep) savedOffset = offset_1, offset_1 = 0; if (offset_1 > maxRep) savedOffset = offset_1, offset_1 = 0;
} }
if (dictMode == ZSTD_dictMatchState) {
/* dictMatchState repCode checks don't currently handle repCode == 0
* disabling. */
assert(offset_1 <= dictAndPrefixLength);
assert(offset_2 <= dictAndPrefixLength);
}
/* Match Loop */ /* Match Loop */
while (ip < ilimit) { while (ip < ilimit) {