poppler/SOURCES/poppler-0.66.0-rescale-filter.patch
2021-09-10 02:10:49 +00:00

101 lines
3.9 KiB
Diff

From 8122f6d6d409b53151a20c5578fc525ee97315e8 Mon Sep 17 00:00:00 2001
From: Marek Kasik <mkasik@redhat.com>
Date: Thu, 21 Mar 2019 13:47:51 +0100
Subject: [PATCH 2/2] cairo: Constrain number of cycles in rescale filter
Pass address of the first byte after end of the source buffer
to downsample_row_box_filter() so that we can check
that we don't run out of it.
Fixes issue #736
---
poppler/CairoRescaleBox.cc | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/poppler/CairoRescaleBox.cc b/poppler/CairoRescaleBox.cc
index d7615010..7fd07041 100644
--- a/poppler/CairoRescaleBox.cc
+++ b/poppler/CairoRescaleBox.cc
@@ -62,7 +62,7 @@
static void downsample_row_box_filter (
int start, int width,
- uint32_t *src, uint32_t *dest,
+ uint32_t *src, uint32_t *src_limit, uint32_t *dest,
int coverage[], int pixel_coverage)
{
/* we need an array of the pixel contribution of each destination pixel on the boundaries.
@@ -90,13 +90,13 @@ static void downsample_row_box_filter (
/* skip to start */
/* XXX: it might be possible to do this directly instead of iteratively, however
* the iterative solution is simple */
- while (x < start)
+ while (x < start && src < src_limit)
{
int box = 1 << FIXED_SHIFT;
int start_coverage = coverage[x];
box -= start_coverage;
src++;
- while (box >= pixel_coverage)
+ while (box >= pixel_coverage && src < src_limit)
{
src++;
box -= pixel_coverage;
@@ -104,7 +104,7 @@ static void downsample_row_box_filter (
x++;
}
- while (x < start + width)
+ while (x < start + width && src < src_limit)
{
uint32_t a = 0;
uint32_t r = 0;
@@ -121,7 +121,7 @@ static void downsample_row_box_filter (
x++;
box -= start_coverage;
- while (box >= pixel_coverage)
+ while (box >= pixel_coverage && src < src_limit)
{
a += ((*src >> 24) & 0xff) * pixel_coverage;
r += ((*src >> 16) & 0xff) * pixel_coverage;
@@ -135,7 +135,7 @@ static void downsample_row_box_filter (
/* multiply by whatever is leftover
* this ensures that we don't bias down.
* i.e. start_coverage + n*pixel_coverage + box == 1 << 24 */
- if (box > 0)
+ if (box > 0 && src < src_limit)
{
a += ((*src >> 24) & 0xff) * box;
r += ((*src >> 16) & 0xff) * box;
@@ -337,7 +337,7 @@ bool CairoRescaleBox::downScaleImage(unsigned orig_width, unsigned orig_height,
int start_coverage_y = y_coverage[dest_y];
getRow(src_y, scanline);
- downsample_row_box_filter (start_column, width, scanline, temp_buf + width * columns, x_coverage, pixel_coverage_x);
+ downsample_row_box_filter (start_column, width, scanline, scanline + orig_width, temp_buf + width * columns, x_coverage, pixel_coverage_x);
columns++;
src_y++;
box -= start_coverage_y;
@@ -345,7 +345,7 @@ bool CairoRescaleBox::downScaleImage(unsigned orig_width, unsigned orig_height,
while (box >= pixel_coverage_y)
{
getRow(src_y, scanline);
- downsample_row_box_filter (start_column, width, scanline, temp_buf + width * columns, x_coverage, pixel_coverage_x);
+ downsample_row_box_filter (start_column, width, scanline, scanline + orig_width, temp_buf + width * columns, x_coverage, pixel_coverage_x);
columns++;
src_y++;
box -= pixel_coverage_y;
@@ -355,7 +355,7 @@ bool CairoRescaleBox::downScaleImage(unsigned orig_width, unsigned orig_height,
if (box > 0)
{
getRow(src_y, scanline);
- downsample_row_box_filter (start_column, width, scanline, temp_buf + width * columns, x_coverage, pixel_coverage_x);
+ downsample_row_box_filter (start_column, width, scanline, scanline + orig_width, temp_buf + width * columns, x_coverage, pixel_coverage_x);
columns++;
}
--
2.20.1