[codec,ncrush] fix bounds checks

This commit is contained in:
akallabeth 2024-04-16 15:35:12 +02:00 committed by akallabeth
parent f3b2aea781
commit b7888e9b3b

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@ -2489,46 +2489,36 @@ static int ncrush_move_encoder_windows(NCRUSH_CONTEXT* ncrush, BYTE* HistoryPtr)
WINPR_ASSERT(ncrush);
WINPR_ASSERT(HistoryPtr);
if (HistoryPtr < &ncrush->HistoryBuffer[32768])
const size_t history_half = ARRAYSIZE(ncrush->HistoryBuffer) / 2;
if (HistoryPtr < &ncrush->HistoryBuffer[history_half])
return -1;
if (HistoryPtr > &ncrush->HistoryBuffer[65536])
if (HistoryPtr > &ncrush->HistoryBuffer[ARRAYSIZE(ncrush->HistoryBuffer)])
return -1;
MoveMemory(ncrush->HistoryBuffer, HistoryPtr - 32768, 32768);
const intptr_t hsize = HistoryPtr - 32768 - ncrush->HistoryBuffer;
WINPR_ASSERT(hsize <= UINT32_MAX);
MoveMemory(ncrush->HistoryBuffer, HistoryPtr - history_half, history_half * sizeof(BYTE));
const intptr_t hsize = HistoryPtr - history_half - ncrush->HistoryBuffer;
WINPR_ASSERT(hsize <= UINT16_MAX);
WINPR_ASSERT(hsize >= 0);
UINT32 HistoryOffset = (UINT32)hsize;
INT32 HistoryOffset = (INT32)hsize;
for (int i = 0; i < 65536; i += 4)
for (size_t i = 0; i < ARRAYSIZE(ncrush->HashTable); i++)
{
INT64 NewHash = ncrush->HashTable[i + 0] - HistoryOffset;
ncrush->HashTable[i + 0] = (NewHash <= 0) ? 0 : NewHash;
NewHash = ncrush->HashTable[i + 1] - HistoryOffset;
ncrush->HashTable[i + 1] = (NewHash <= 0) ? 0 : NewHash;
NewHash = ncrush->HashTable[i + 2] - HistoryOffset;
ncrush->HashTable[i + 2] = (NewHash <= 0) ? 0 : NewHash;
NewHash = ncrush->HashTable[i + 3] - HistoryOffset;
ncrush->HashTable[i + 3] = (NewHash <= 0) ? 0 : NewHash;
INT32 NewHash = ncrush->HashTable[i] - HistoryOffset;
ncrush->HashTable[i] = (NewHash <= 0) ? 0 : NewHash;
}
for (int j = 0; j < 32768; j += 4)
const size_t match_half = ARRAYSIZE(ncrush->MatchTable) / 2;
for (size_t j = 0; j < match_half; j++)
{
if (HistoryOffset + j + 3ull > ARRAYSIZE(ncrush->MatchTable))
if (HistoryOffset + j > ARRAYSIZE(ncrush->MatchTable))
continue;
INT64 NewMatch = ncrush->MatchTable[HistoryOffset + j + 0] - HistoryOffset;
ncrush->MatchTable[j + 0] = (NewMatch <= 0) ? 0 : NewMatch;
NewMatch = ncrush->MatchTable[HistoryOffset + j + 1] - HistoryOffset;
ncrush->MatchTable[j + 1] = (NewMatch <= 0) ? 0 : NewMatch;
NewMatch = ncrush->MatchTable[HistoryOffset + j + 2] - HistoryOffset;
ncrush->MatchTable[j + 2] = (NewMatch <= 0) ? 0 : NewMatch;
NewMatch = ncrush->MatchTable[HistoryOffset + j + 3] - HistoryOffset;
ncrush->MatchTable[j + 3] = (NewMatch <= 0) ? 0 : NewMatch;
INT32 NewMatch = ncrush->MatchTable[HistoryOffset + j] - HistoryOffset;
ncrush->MatchTable[j] = (NewMatch <= 0) ? 0 : NewMatch;
}
ZeroMemory(&ncrush->MatchTable[32768], 65536);
ZeroMemory(&ncrush->MatchTable[match_half], match_half * sizeof(UINT16));
return 1;
}