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-rw-r--r--gfx/ots/src/cff.cc140
1 files changed, 75 insertions, 65 deletions
diff --git a/gfx/ots/src/cff.cc b/gfx/ots/src/cff.cc
index af54a4a16c..95ff7f744b 100644
--- a/gfx/ots/src/cff.cc
+++ b/gfx/ots/src/cff.cc
@@ -41,7 +41,7 @@ enum FONT_FORMAT {
// see Appendix. A
const size_t kNStdString = 390;
-typedef std::pair<uint32_t, DICT_OPERAND_TYPE> Operand;
+typedef std::pair<int32_t, DICT_OPERAND_TYPE> Operand;
bool ReadOffset(ots::Buffer &table, uint8_t off_size, uint32_t *offset) {
if (off_size > 4) {
@@ -172,7 +172,7 @@ bool CheckOffset(const Operand& operand, size_t table_length) {
if (operand.second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- if (operand.first >= table_length) {
+ if (operand.first >= static_cast<int32_t>(table_length) || operand.first < 0) {
return OTS_FAILURE();
}
return true;
@@ -182,7 +182,7 @@ bool CheckSid(const Operand& operand, size_t sid_max) {
if (operand.second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- if (operand.first > sid_max) {
+ if (operand.first > static_cast<int32_t>(sid_max) || operand.first < 0) {
return OTS_FAILURE();
}
return true;
@@ -202,15 +202,13 @@ bool ParseDictDataBcd(ots::Buffer &table, std::vector<Operand> &operands) {
if ((nibble & 0xf) == 0xf) {
// TODO(yusukes): would be better to store actual double value,
// rather than the dummy integer.
- operands.push_back(std::make_pair(static_cast<uint32_t>(0),
- DICT_OPERAND_REAL));
+ operands.push_back(std::make_pair(0, DICT_OPERAND_REAL));
return true;
}
return OTS_FAILURE();
}
if ((nibble & 0x0f) == 0x0f) {
- operands.push_back(std::make_pair(static_cast<uint32_t>(0),
- DICT_OPERAND_REAL));
+ operands.push_back(std::make_pair(0, DICT_OPERAND_REAL));
return true;
}
@@ -256,7 +254,7 @@ bool ParseDictDataEscapedOperator(ots::Buffer &table,
if ((op <= 14) ||
(op >= 17 && op <= 23) ||
(op >= 30 && op <= 38)) {
- operands.push_back(std::make_pair((12U << 8) + op, DICT_OPERATOR));
+ operands.push_back(std::make_pair((12 << 8) + op, DICT_OPERATOR));
return true;
}
@@ -277,8 +275,9 @@ bool ParseDictDataNumber(ots::Buffer &table, uint8_t b0,
!table.ReadU8(&b2)) {
return OTS_FAILURE();
}
+ //the two-byte value needs to be casted to int16_t in order to get the right sign
operands.push_back(std::make_pair(
- static_cast<uint32_t>((b1 << 8) + b2), DICT_OPERAND_INTEGER));
+ static_cast<int16_t>((b1 << 8) + b2), DICT_OPERAND_INTEGER));
return true;
case 29: // longint
@@ -289,7 +288,7 @@ bool ParseDictDataNumber(ots::Buffer &table, uint8_t b0,
return OTS_FAILURE();
}
operands.push_back(std::make_pair(
- static_cast<uint32_t>((b1 << 24) + (b2 << 16) + (b3 << 8) + b4),
+ (b1 << 24) + (b2 << 16) + (b3 << 8) + b4,
DICT_OPERAND_INTEGER));
return true;
@@ -300,7 +299,7 @@ bool ParseDictDataNumber(ots::Buffer &table, uint8_t b0,
break;
}
- uint32_t result;
+ int32_t result;
if (b0 >=32 && b0 <=246) {
result = b0 - 139;
} else if (b0 >=247 && b0 <= 250) {
@@ -332,7 +331,7 @@ bool ParseDictDataReadNext(ots::Buffer &table,
return ParseDictDataEscapedOperator(table, operands);
}
operands.push_back(std::make_pair(
- static_cast<uint32_t>(op), DICT_OPERATOR));
+ static_cast<int32_t>(op), DICT_OPERATOR));
return true;
} else if (op <= 27 || op == 31 || op == 255) {
// reserved area.
@@ -367,13 +366,13 @@ bool ParseDictDataReadOperands(ots::Buffer& dict,
return true;
}
-bool ValidCFF2DictOp(uint32_t op, DICT_DATA_TYPE type) {
+bool ValidCFF2DictOp(int32_t op, DICT_DATA_TYPE type) {
if (type == DICT_DATA_TOPLEVEL) {
switch (op) {
- case (12U << 8) + 7: // FontMatrix
+ case (12 << 8) + 7: // FontMatrix
case 17: // CharStrings
- case (12U << 8) + 36: // FDArray
- case (12U << 8) + 37: // FDSelect
+ case (12 << 8) + 36: // FDArray
+ case (12 << 8) + 37: // FDSelect
case 24: // vstore
return true;
default:
@@ -384,8 +383,8 @@ bool ValidCFF2DictOp(uint32_t op, DICT_DATA_TYPE type) {
return true;
} else if (type == DICT_DATA_PRIVATE) {
switch (op) {
- case (12U << 8) + 14: // ForceBold
- case (12U << 8) + 19: // initialRandomSeed
+ case (12 << 8) + 14: // ForceBold
+ case (12 << 8) + 19: // initialRandomSeed
case 20: // defaultWidthX
case 21: // nominalWidthX
return false;
@@ -426,7 +425,7 @@ bool ParsePrivateDictData(
}
// got operator
- const uint32_t op = operands.back().first;
+ const int32_t op = operands.back().first;
operands.pop_back();
if (cff2 && !ValidCFF2DictOp(op, DICT_DATA_PRIVATE)) {
@@ -446,8 +445,8 @@ bool ParsePrivateDictData(
break;
// array
- case (12U << 8) + 12: // StemSnapH (delta)
- case (12U << 8) + 13: // StemSnapV (delta)
+ case (12 << 8) + 12: // StemSnapH (delta)
+ case (12 << 8) + 13: // StemSnapV (delta)
if (operands.empty()) {
return OTS_FAILURE();
}
@@ -458,12 +457,12 @@ bool ParsePrivateDictData(
case 11: // StdVW
case 20: // defaultWidthX
case 21: // nominalWidthX
- case (12U << 8) + 9: // BlueScale
- case (12U << 8) + 10: // BlueShift
- case (12U << 8) + 11: // BlueFuzz
- case (12U << 8) + 17: // LanguageGroup
- case (12U << 8) + 18: // ExpansionFactor
- case (12U << 8) + 19: // initialRandomSeed
+ case (12 << 8) + 9: // BlueScale
+ case (12 << 8) + 10: // BlueShift
+ case (12 << 8) + 11: // BlueFuzz
+ case (12 << 8) + 17: // LanguageGroup
+ case (12 << 8) + 18: // ExpansionFactor
+ case (12 << 8) + 19: // initialRandomSeed
if (operands.size() != 1) {
return OTS_FAILURE();
}
@@ -477,7 +476,14 @@ bool ParsePrivateDictData(
if (operands.back().second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- if (operands.back().first >= 1024 * 1024 * 1024) {
+ // In theory a negative operand could occur here, if the Local Subrs
+ // were stored before the Private dict, but this does not seem to be
+ // well supported by implementations, and mishandling of a negative
+ // offset (e.g. by using unsigned offset arithmetic) might become a
+ // vector for exploitation. AFAIK no major font creation tool will
+ // generate such an offset, so to be on the safe side, we don't allow
+ // it here.
+ if (operands.back().first >= 1024 * 1024 * 1024 || operands.back().first < 0) {
return OTS_FAILURE();
}
if (operands.back().first + offset >= table.length()) {
@@ -505,14 +511,14 @@ bool ParsePrivateDictData(
}
// boolean
- case (12U << 8) + 14: // ForceBold
+ case (12 << 8) + 14: // ForceBold
if (operands.size() != 1) {
return OTS_FAILURE();
}
if (operands.back().second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- if (operands.back().first >= 2) {
+ if (operands.back().first >= 2 || operands.back().first < 0) {
return OTS_FAILURE();
}
break;
@@ -532,7 +538,7 @@ bool ParsePrivateDictData(
}
vsindex = operands.back().first;
if (vsindex < 0 ||
- vsindex >= (int32_t)out_cff->region_index_count.size()) {
+ vsindex >= static_cast<int32_t>(out_cff->region_index_count.size())) {
return OTS_FAILURE();
}
out_cff->vsindex_per_font.back() = vsindex;
@@ -546,11 +552,15 @@ bool ParsePrivateDictData(
if (operands.size() < 1) {
return OTS_FAILURE();
}
- if (vsindex >= (int32_t)out_cff->region_index_count.size()) {
+ if (vsindex >= static_cast<int32_t>(out_cff->region_index_count.size())) {
return OTS_FAILURE();
}
uint16_t k = out_cff->region_index_count.at(vsindex);
- uint16_t n = operands.back().first;
+
+ if (operands.back().first > static_cast<uint16_t>(0xffff) || operands.back().first < 0){
+ return OTS_FAILURE();
+ }
+ uint16_t n = static_cast<uint16_t>(operands.back().first);
if (operands.size() < n * (k + 1) + 1) {
return OTS_FAILURE();
}
@@ -644,7 +654,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
if (operands.back().second != DICT_OPERATOR) continue;
// got operator
- const uint32_t op = operands.back().first;
+ const int32_t op = operands.back().first;
operands.pop_back();
if (op == 18 && type == DICT_DATA_FDARRAY) {
@@ -686,7 +696,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
if (operands.back().second != DICT_OPERATOR) continue;
// got operator
- const uint32_t op = operands.back().first;
+ const int32_t op = operands.back().first;
operands.pop_back();
if (cff2 && !ValidCFF2DictOp(op, type)) {
@@ -700,10 +710,10 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
case 2: // Copyright
case 3: // FullName
case 4: // FamilyName
- case (12U << 8) + 0: // Copyright
- case (12U << 8) + 21: // PostScript
- case (12U << 8) + 22: // BaseFontName
- case (12U << 8) + 38: // FontName
+ case (12 << 8) + 0: // Copyright
+ case (12 << 8) + 21: // PostScript
+ case (12 << 8) + 22: // BaseFontName
+ case (12 << 8) + 38: // FontName
if (operands.size() != 1) {
return OTS_FAILURE();
}
@@ -715,8 +725,8 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
// array
case 5: // FontBBox
case 14: // XUID
- case (12U << 8) + 7: // FontMatrix
- case (12U << 8) + 23: // BaseFontBlend (delta)
+ case (12 << 8) + 7: // FontMatrix
+ case (12 << 8) + 23: // BaseFontBlend (delta)
if (operands.empty()) {
return OTS_FAILURE();
}
@@ -724,21 +734,21 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
// number
case 13: // UniqueID
- case (12U << 8) + 2: // ItalicAngle
- case (12U << 8) + 3: // UnderlinePosition
- case (12U << 8) + 4: // UnderlineThickness
- case (12U << 8) + 5: // PaintType
- case (12U << 8) + 8: // StrokeWidth
- case (12U << 8) + 20: // SyntheticBase
+ case (12 << 8) + 2: // ItalicAngle
+ case (12 << 8) + 3: // UnderlinePosition
+ case (12 << 8) + 4: // UnderlineThickness
+ case (12 << 8) + 5: // PaintType
+ case (12 << 8) + 8: // StrokeWidth
+ case (12 << 8) + 20: // SyntheticBase
if (operands.size() != 1) {
return OTS_FAILURE();
}
break;
- case (12U << 8) + 31: // CIDFontVersion
- case (12U << 8) + 32: // CIDFontRevision
- case (12U << 8) + 33: // CIDFontType
- case (12U << 8) + 34: // CIDCount
- case (12U << 8) + 35: // UIDBase
+ case (12 << 8) + 31: // CIDFontVersion
+ case (12 << 8) + 32: // CIDFontRevision
+ case (12 << 8) + 33: // CIDFontType
+ case (12 << 8) + 34: // CIDCount
+ case (12 << 8) + 35: // UIDBase
if (operands.size() != 1) {
return OTS_FAILURE();
}
@@ -746,7 +756,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
return OTS_FAILURE();
}
break;
- case (12U << 8) + 6: // CharstringType
+ case (12 << 8) + 6: // CharstringType
if (operands.size() != 1) {
return OTS_FAILURE();
}
@@ -761,14 +771,14 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
break;
// boolean
- case (12U << 8) + 1: // isFixedPitch
+ case (12 << 8) + 1: // isFixedPitch
if (operands.size() != 1) {
return OTS_FAILURE();
}
if (operands.back().second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- if (operands.back().first >= 2) {
+ if (operands.back().first >= 2 || operands.back().first < 0) {
return OTS_FAILURE();
}
break;
@@ -778,7 +788,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
if (operands.size() != 1) {
return OTS_FAILURE();
}
- if (operands.back().first <= 2) {
+ if (operands.back().first <= 2 && operands.back().first >= 0) {
// predefined charset, ISOAdobe, Expert or ExpertSubset, is used.
break;
}
@@ -795,7 +805,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
if (operands.size() != 1) {
return OTS_FAILURE();
}
- if (operands.back().first <= 1) {
+ if (operands.back().first <= 1 && operands.back().first >= 0) {
break; // predefined encoding, "Standard" or "Expert", is used.
}
if (!CheckOffset(operands.back(), table.length())) {
@@ -856,7 +866,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
break;
}
- case (12U << 8) + 36: { // FDArray
+ case (12 << 8) + 36: { // FDArray
if (type != DICT_DATA_TOPLEVEL) {
return OTS_FAILURE();
}
@@ -885,7 +895,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
break;
}
- case (12U << 8) + 37: { // FDSelect
+ case (12 << 8) + 37: { // FDSelect
if (type != DICT_DATA_TOPLEVEL) {
return OTS_FAILURE();
}
@@ -1043,19 +1053,19 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
if (operands.back().second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- const uint32_t private_offset = operands.back().first;
+ const int32_t private_offset = operands.back().first;
operands.pop_back();
if (operands.back().second != DICT_OPERAND_INTEGER) {
return OTS_FAILURE();
}
- const uint32_t private_length = operands.back().first;
- if (private_offset > table.length()) {
+ const int32_t private_length = operands.back().first;
+ if (private_offset > static_cast<int32_t>(table.length())) {
return OTS_FAILURE();
}
- if (private_length >= table.length()) {
+ if (private_length >= static_cast<int32_t>(table.length()) || private_length < 0) {
return OTS_FAILURE();
}
- if (private_length + private_offset > table.length()) {
+ if (private_length + private_offset > static_cast<int32_t>(table.length()) || private_length + private_offset < 0) {
return OTS_FAILURE();
}
// parse "15. Private DICT data"
@@ -1067,7 +1077,7 @@ bool ParseDictData(ots::Buffer& table, ots::Buffer& dict,
}
// ROS
- case (12U << 8) + 30:
+ case (12 << 8) + 30:
if (font_format != FORMAT_UNKNOWN) {
return OTS_FAILURE();
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-14 13:35:42 +0000