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Merge pull request #1696 from terrelln/legacy-fix

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[legacy] Fix bug in zstd-0.5 decoder
This commit is contained in:
Nick Terrell 2019-07-22 18:06:18 -04:00 committed by GitHub
commit 740b32173f
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1 changed files with 16 additions and 13 deletions
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29
lib/legacy/zstd_v05.c
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@ -218,11 +218,6 @@ MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val)
} }
} }
MEM_STATIC U32 MEM_readLE24(const void* memPtr)
{
return MEM_readLE16(memPtr) + (((const BYTE*)memPtr)[2] << 16);
}
MEM_STATIC U32 MEM_readLE32(const void* memPtr) MEM_STATIC U32 MEM_readLE32(const void* memPtr)
{ {
if (MEM_isLittleEndian()) if (MEM_isLittleEndian())
@ -3158,10 +3153,14 @@ static void ZSTDv05_decodeSequence(seq_t* seq, seqState_t* seqState)
if (litLength == MaxLL) { if (litLength == MaxLL) {
const U32 add = *dumps++; const U32 add = *dumps++;
if (add < 255) litLength += add; if (add < 255) litLength += add;
else if (dumps + 3 <= de) { else if (dumps + 2 <= de) {
litLength = MEM_readLE24(dumps); litLength = MEM_readLE16(dumps);
if (litLength&1) litLength>>=1, dumps += 3; dumps += 2;
else litLength = (U16)(litLength)>>1, dumps += 2; if ((litLength & 1) && dumps < de) {
litLength += *dumps << 16;
dumps += 1;
}
litLength>>=1;
} }
if (dumps >= de) { dumps = de-1; } /* late correction, to avoid read overflow (data is now corrupted anyway) */ if (dumps >= de) { dumps = de-1; } /* late correction, to avoid read overflow (data is now corrupted anyway) */
} }
@ -3191,10 +3190,14 @@ static void ZSTDv05_decodeSequence(seq_t* seq, seqState_t* seqState)
if (matchLength == MaxML) { if (matchLength == MaxML) {
const U32 add = dumps<de ? *dumps++ : 0; const U32 add = dumps<de ? *dumps++ : 0;
if (add < 255) matchLength += add; if (add < 255) matchLength += add;
else if (dumps + 3 <= de) { else if (dumps + 2 <= de) {
matchLength = MEM_readLE24(dumps); matchLength = MEM_readLE16(dumps);
if (matchLength&1) matchLength>>=1, dumps += 3; dumps += 2;
else matchLength = (U16)(matchLength)>>1, dumps += 2; if ((matchLength & 1) && dumps < de) {
matchLength += *dumps << 16;
dumps += 1;
}
matchLength >>= 1;
} }
if (dumps >= de) { dumps = de-1; } /* late correction, to avoid read overflow (data is now corrupted anyway) */ if (dumps >= de) { dumps = de-1; } /* late correction, to avoid read overflow (data is now corrupted anyway) */
} }