Fix a couple of divide by zero crashes in PNG/TIFF predictors.
BUG=484002
R=tsepez@chromium.org
Review URL: https://codereview.chromium.org/1124563002
diff --git a/core/src/fxcodec/codec/fx_codec_flate.cpp b/core/src/fxcodec/codec/fx_codec_flate.cpp
index 3e1aa36..76514ba 100644
--- a/core/src/fxcodec/codec/fx_codec_flate.cpp
+++ b/core/src/fxcodec/codec/fx_codec_flate.cpp
@@ -4,9 +4,11 @@
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
-#include "../../fx_zlib.h"
+#include "../../../../third_party/base/nonstd_unique_ptr.h"
#include "../../../include/fxcodec/fx_codec.h"
+#include "../../fx_zlib.h"
#include "codec_int.h"
+
extern "C"
{
static void* my_alloc_func (void* opaque, unsigned int items, unsigned int size)
@@ -229,16 +231,19 @@
}
return (FX_BYTE)c;
}
-static void PNG_PredictorEncode(FX_LPBYTE& data_buf, FX_DWORD& data_size, int predictor, int Colors, int BitsPerComponent, int Columns)
+static FX_BOOL PNG_PredictorEncode(FX_LPBYTE& data_buf, FX_DWORD& data_size,
+ int predictor, int Colors,
+ int BitsPerComponent, int Columns)
{
- int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
- int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
- int row_count = (data_size + row_size - 1) / row_size;
- int last_row_size = data_size % row_size;
+ const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
+ const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
+ if (row_size <= 0)
+ return FALSE;
+ const int row_count = (data_size + row_size - 1) / row_size;
+ const int last_row_size = data_size % row_size;
FX_LPBYTE dest_buf = FX_Alloc( FX_BYTE, (row_size + 1) * row_count);
- if (dest_buf == NULL) {
- return;
- }
+ if (dest_buf == NULL)
+ return FALSE;
int byte_cnt = 0;
FX_LPBYTE pSrcData = data_buf;
FX_LPBYTE pDestData = dest_buf;
@@ -318,6 +323,7 @@
FX_Free(data_buf);
data_buf = dest_buf;
data_size = (row_size + 1) * row_count - (last_row_size > 0 ? (row_size - last_row_size) : 0);
+ return TRUE;
}
static void PNG_PredictLine(FX_LPBYTE pDestData, FX_LPCBYTE pSrcData, FX_LPCBYTE pLastLine,
int bpc, int nColors, int nPixels)
@@ -382,17 +388,18 @@
}
}
}
-static void PNG_Predictor(FX_LPBYTE& data_buf, FX_DWORD& data_size,
- int Colors, int BitsPerComponent, int Columns)
+static FX_BOOL PNG_Predictor(FX_LPBYTE& data_buf, FX_DWORD& data_size,
+ int Colors, int BitsPerComponent, int Columns)
{
- int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
- int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
- int row_count = (data_size + row_size) / (row_size + 1);
- int last_row_size = data_size % (row_size + 1);
+ const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
+ const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
+ if (row_size <= 0)
+ return FALSE;
+ const int row_count = (data_size + row_size) / (row_size + 1);
+ const int last_row_size = data_size % (row_size + 1);
FX_LPBYTE dest_buf = FX_Alloc( FX_BYTE, row_size * row_count);
- if (dest_buf == NULL) {
- return;
- }
+ if (dest_buf == NULL)
+ return FALSE;
int byte_cnt = 0;
FX_LPBYTE pSrcData = data_buf;
FX_LPBYTE pDestData = dest_buf;
@@ -469,6 +476,7 @@
FX_Free(data_buf);
data_buf = dest_buf;
data_size = row_size * row_count - (last_row_size > 0 ? (row_size + 1 - last_row_size) : 0);
+ return TRUE;
}
static void TIFF_PredictorEncodeLine(FX_LPBYTE dest_buf, int row_size, int BitsPerComponent, int Colors, int Columns)
{
@@ -507,12 +515,14 @@
}
}
}
-static void TIFF_PredictorEncode(FX_LPBYTE& data_buf, FX_DWORD& data_size,
- int Colors, int BitsPerComponent, int Columns)
+static FX_BOOL TIFF_PredictorEncode(FX_LPBYTE& data_buf, FX_DWORD& data_size,
+ int Colors, int BitsPerComponent, int Columns)
{
int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
- int row_count = (data_size + row_size - 1) / row_size;
- int last_row_size = data_size % row_size;
+ if (row_size == 0)
+ return FALSE;
+ const int row_count = (data_size + row_size - 1) / row_size;
+ const int last_row_size = data_size % row_size;
for (int row = 0; row < row_count; row++) {
FX_LPBYTE scan_line = data_buf + row * row_size;
if ((row + 1) * row_size > (int)data_size) {
@@ -520,6 +530,7 @@
}
TIFF_PredictorEncodeLine(scan_line, row_size, BitsPerComponent, Colors, Columns);
}
+ return TRUE;
}
static void TIFF_PredictLine(FX_LPBYTE dest_buf, int row_size, int BitsPerComponent, int Colors, int Columns)
{
@@ -554,12 +565,14 @@
}
}
}
-static void TIFF_Predictor(FX_LPBYTE& data_buf, FX_DWORD& data_size,
- int Colors, int BitsPerComponent, int Columns)
+static FX_BOOL TIFF_Predictor(FX_LPBYTE& data_buf, FX_DWORD& data_size,
+ int Colors, int BitsPerComponent, int Columns)
{
int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
- int row_count = (data_size + row_size - 1) / row_size;
- int last_row_size = data_size % row_size;
+ if (row_size == 0)
+ return FALSE;
+ const int row_count = (data_size + row_size - 1) / row_size;
+ const int last_row_size = data_size % row_size;
for (int row = 0; row < row_count; row ++) {
FX_LPBYTE scan_line = data_buf + row * row_size;
if ((row + 1) * row_size > (int)data_size) {
@@ -567,6 +580,7 @@
}
TIFF_PredictLine(scan_line, row_size, BitsPerComponent, Colors, Columns);
}
+ return TRUE;
}
class CCodec_FlateScanlineDecoder : public CCodec_ScanlineDecoder
{
@@ -859,7 +873,6 @@
int predictor, int Colors, int BitsPerComponent, int Columns,
FX_DWORD estimated_size, FX_LPBYTE& dest_buf, FX_DWORD& dest_size)
{
- CLZWDecoder* pDecoder = NULL;
dest_buf = NULL;
FX_DWORD offset = 0;
int predictor_type = 0;
@@ -871,34 +884,40 @@
}
}
if (bLZW) {
- pDecoder = new CLZWDecoder;
- dest_size = (FX_DWORD) - 1;
- offset = src_size;
- int err = pDecoder->Decode(NULL, dest_size, src_buf, offset, bEarlyChange);
- delete pDecoder;
- if (err || dest_size == 0 || dest_size + 1 < dest_size) {
- return (FX_DWORD) - 1;
+ {
+ nonstd::unique_ptr<CLZWDecoder> decoder(new CLZWDecoder);
+ dest_size = (FX_DWORD) - 1;
+ offset = src_size;
+ int err = decoder->Decode(NULL, dest_size, src_buf, offset,
+ bEarlyChange);
+ if (err || dest_size == 0 || dest_size + 1 < dest_size) {
+ return -1;
+ }
}
- pDecoder = new CLZWDecoder;
- dest_buf = FX_Alloc( FX_BYTE, dest_size + 1);
- if (dest_buf == NULL) {
- return -1;
+ {
+ nonstd::unique_ptr<CLZWDecoder> decoder(new CLZWDecoder);
+ dest_buf = FX_Alloc( FX_BYTE, dest_size + 1);
+ if (dest_buf == NULL) {
+ return -1;
+ }
+ dest_buf[dest_size] = '\0';
+ decoder->Decode(dest_buf, dest_size, src_buf, offset, bEarlyChange);
}
- dest_buf[dest_size] = '\0';
- pDecoder->Decode(dest_buf, dest_size, src_buf, offset, bEarlyChange);
- delete pDecoder;
} else {
FlateUncompress(src_buf, src_size, estimated_size, dest_buf, dest_size, offset);
}
if (predictor_type == 0) {
return offset;
}
+ FX_BOOL ret = TRUE;
if (predictor_type == 2) {
- PNG_Predictor(dest_buf, dest_size, Colors, BitsPerComponent, Columns);
+ ret = PNG_Predictor(dest_buf, dest_size, Colors, BitsPerComponent,
+ Columns);
} else if (predictor_type == 1) {
- TIFF_Predictor(dest_buf, dest_size, Colors, BitsPerComponent, Columns);
+ ret = TIFF_Predictor(dest_buf, dest_size, Colors, BitsPerComponent,
+ Columns);
}
- return offset;
+ return ret ? offset : -1;
}
FX_BOOL CCodec_FlateModule::Encode(const FX_BYTE* src_buf, FX_DWORD src_size,
int predictor, int Colors, int BitsPerComponent, int Columns,
@@ -907,19 +926,22 @@
if (predictor != 2 && predictor < 10) {
return Encode(src_buf, src_size, dest_buf, dest_size);
}
- FX_BOOL ret = FALSE;
FX_LPBYTE pSrcBuf = NULL;
pSrcBuf = FX_Alloc(FX_BYTE, src_size);
if (pSrcBuf == NULL) {
return FALSE;
}
FXSYS_memcpy32(pSrcBuf, src_buf, src_size);
+ FX_BOOL ret = TRUE;
if (predictor == 2) {
- TIFF_PredictorEncode(pSrcBuf, src_size, Colors, BitsPerComponent, Columns);
+ ret = TIFF_PredictorEncode(pSrcBuf, src_size, Colors, BitsPerComponent,
+ Columns);
} else if (predictor >= 10) {
- PNG_PredictorEncode(pSrcBuf, src_size, predictor, Colors, BitsPerComponent, Columns);
+ ret = PNG_PredictorEncode(pSrcBuf, src_size, predictor, Colors,
+ BitsPerComponent, Columns);
}
- ret = Encode(pSrcBuf, src_size, dest_buf, dest_size);
+ if (ret)
+ ret = Encode(pSrcBuf, src_size, dest_buf, dest_size);
FX_Free(pSrcBuf);
return ret;
}
