libpng/libpng-CVE-2015-8126.patch
Petr Hracek 6ce4092697 fix for CVE-2015-8126 (#1281756, #1281757). Proper patch
Signed-off-by: Petr Hracek <phracek@redhat.com>
2015-11-18 12:30:00 +01:00

101 lines
3.3 KiB
Diff

diff --git a/pngrutil.c b/pngrutil.c
index 8f8edbc..5ca4dcb 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -866,7 +866,7 @@ void /* PRIVATE */
png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
{
png_color palette[PNG_MAX_PALETTE_LENGTH];
- int num, i;
+ int max_palette_length, num, i;
#ifdef PNG_POINTER_INDEXING_SUPPORTED
png_colorp pal_ptr;
#endif
@@ -927,6 +927,14 @@ png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
/* The cast is safe because 'length' is less than 3*PNG_MAX_PALETTE_LENGTH */
num = (int)length / 3;
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ max_palette_length = (1 << png_ptr->bit_depth);
+ else
+ max_palette_length = PNG_MAX_PALETTE_LENGTH;
+
+ if (num > max_palette_length)
+ num = max_palette_length;
+
#ifdef PNG_POINTER_INDEXING_SUPPORTED
for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)
{
@@ -959,7 +967,7 @@ png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
#endif
{
- png_crc_finish(png_ptr, 0);
+ png_crc_finish(png_ptr, (int) length - num * 3);
}
#ifndef PNG_READ_OPT_PLTE_SUPPORTED
diff --git a/pngset.c b/pngset.c
index 5f62af1..42e0dc2 100644
--- a/pngset.c
+++ b/pngset.c
@@ -513,12 +513,17 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
png_const_colorp palette, int num_palette)
{
+ png_uint_32 max_palette_length;
+
png_debug1(1, "in %s storage function", "PLTE");
if (png_ptr == NULL || info_ptr == NULL)
return;
- if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
+ max_palette_length = (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
+ (1 << png_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;
+
+ if (num_palette < 0 || num_palette > (int) max_palette_length)
{
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
png_error(png_ptr, "Invalid palette length");
diff --git a/pngwrite.c b/pngwrite.c
index 3c8cbbe..39ef69e 100644
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -206,7 +206,7 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
png_write_PLTE(png_ptr, info_ptr->palette,
(png_uint_32)info_ptr->num_palette);
- else if ((info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) !=0)
+ else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
png_error(png_ptr, "Valid palette required for paletted images");
#ifdef PNG_WRITE_tRNS_SUPPORTED
diff --git a/pngwutil.c b/pngwutil.c
index 9e6019e..01be584 100644
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -922,17 +922,20 @@ void /* PRIVATE */
png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
png_uint_32 num_pal)
{
- png_uint_32 i;
+ png_uint_32 max_palette_length, i;
png_const_colorp pal_ptr;
png_byte buf[3];
png_debug(1, "in png_write_PLTE");
+ max_palette_length = (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
+ (1 << png_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;
+
if ((
#ifdef PNG_MNG_FEATURES_SUPPORTED
(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 &&
#endif
- num_pal == 0) || num_pal > 256)
+ num_pal == 0) || num_pal > max_palette_length)
{
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{