Fix DDSS Load

This PR fixes an incorrect comparison in figuring out `minChain` in
`ZSTD_dedicatedDictSearch_lazy_loadDictionary()`. This incorrect comparison
had been masked by the fact that `idx` was always 1, until @terrelln changed
that in #2726.

Credit-to: OSS-Fuzz
This commit is contained in:
W. Felix Handte 2021-07-22 12:37:35 -04:00
parent d2b5e5496d
commit da58821ff2

View File

@ -450,7 +450,7 @@ void ZSTD_dedicatedDictSearch_lazy_loadDictionary(ZSTD_matchState_t* ms, const B
U32* const chainTable = ms->chainTable;
U32 const chainSize = 1 << ms->cParams.chainLog;
U32 idx = ms->nextToUpdate;
U32 const minChain = chainSize < target ? target - chainSize : idx;
U32 const minChain = chainSize < target - idx ? target - chainSize : idx;
U32 const bucketSize = 1 << ZSTD_LAZY_DDSS_BUCKET_LOG;
U32 const cacheSize = bucketSize - 1;
U32 const chainAttempts = (1 << ms->cParams.searchLog) - cacheSize;