Disallow Too-Long Repcodes When Using an Attached Dict
diff --git a/lib/compress/zstd_lazy.c b/lib/compress/zstd_lazy.c
index d9695f1..4d4d81e 100644
--- a/lib/compress/zstd_lazy.c
+++ b/lib/compress/zstd_lazy.c
@@ -503,15 +503,33 @@
(searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS);
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;
/* init */
- ip += (ip==prefixLowest);
+ ip += (dictAndPrefixLength == 0);
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_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 */
while (ip < ilimit) {
