cairo: don't overflow y * stride when accessing image data
diff --git a/poppler/CairoOutputDev.cc b/poppler/CairoOutputDev.cc
index 43c604f..cc8a161 100644
--- a/poppler/CairoOutputDev.cc
+++ b/poppler/CairoOutputDev.cc
@@ -1834,7 +1834,7 @@
/* convert to a luminocity map */
uint32_t *source_data = (uint32_t*)cairo_image_surface_get_data(source);
/* get stride in units of 32 bits */
- int stride = cairo_image_surface_get_stride(source)/4;
+ ptrdiff_t stride = cairo_image_surface_get_stride(source)/4;
for (int y=0; y<height; y++) {
for (int x=0; x<width; x++) {
int lum = alpha ? fill_opacity : luminocity(source_data[y*stride + x]);
@@ -2127,7 +2127,7 @@
Guchar *pix;
cairo_matrix_t matrix;
int invert_bit;
- int row_stride;
+ ptrdiff_t row_stride;
cairo_filter_t filter;
/* TODO: Do we want to cache these? */
@@ -2234,7 +2234,7 @@
Guchar *pix;
cairo_matrix_t matrix;
int invert_bit;
- int row_stride;
+ ptrdiff_t row_stride;
/* cairo does a very poor job of scaling down images so we scale them ourselves */
@@ -2527,7 +2527,7 @@
GBool maskInterpolate)
{
ImageStream *maskImgStr, *imgStr;
- int row_stride;
+ ptrdiff_t row_stride;
unsigned char *maskBuffer, *buffer;
unsigned char *maskDest;
unsigned int *dest;
@@ -2685,7 +2685,7 @@
GBool maskInterpolate)
{
ImageStream *maskImgStr, *imgStr;
- int row_stride;
+ ptrdiff_t row_stride;
unsigned char *maskBuffer, *buffer;
unsigned char *maskDest;
unsigned int *dest;
@@ -3088,7 +3088,7 @@
if (!needsCustomDownscaling || printing || scaledWidth >= width || scaledHeight >= height) {
// No downscaling. Create cairo image containing the source image data.
unsigned char *buffer;
- int stride;
+ ptrdiff_t stride;
image = cairo_image_surface_create (maskColors ?
CAIRO_FORMAT_ARGB32 :
