diff options
| author | aavit <qt-info@nokia.com> | 2011-10-19 14:02:24 +0200 |
|---|---|---|
| committer | aavit <qt-info@nokia.com> | 2011-10-19 14:05:48 +0200 |
| commit | 55c2ea18c522bd8700f43884124e02b460cdb5e2 (patch) | |
| tree | cc0d98b7a624531fbd32ea2b3250143b31ae8c38 | |
| parent | fa717293080c9d00b02028bebece1935aef6e093 (diff) | |
Fixes: the png_handle_cHRM crash bug in bundled libpng 1.5.4
The PNG Development Group explains that libpng 1.5.4 (only) introduced
a divide-by-zero bug in png_handle_cHRM(), which could lead to crashes
(denial of service) for certain malformed PNGs.
Ref. http://www.libpng.org/pub/png/libpng.html
Task-number: QTBUG-22168
| -rw-r--r-- | src/3rdparty/libpng/pngrutil.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/src/3rdparty/libpng/pngrutil.c b/src/3rdparty/libpng/pngrutil.c index 07e46e2fed..daf3c5e099 100644 --- a/src/3rdparty/libpng/pngrutil.c +++ b/src/3rdparty/libpng/pngrutil.c @@ -1037,12 +1037,14 @@ png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) */ png_uint_32 w = y_red + y_green + y_blue; - png_ptr->rgb_to_gray_red_coeff = (png_uint_16)(((png_uint_32)y_red * - 32768)/w); - png_ptr->rgb_to_gray_green_coeff = (png_uint_16)(((png_uint_32)y_green - * 32768)/w); - png_ptr->rgb_to_gray_blue_coeff = (png_uint_16)(((png_uint_32)y_blue * - 32768)/w); + if (w != 0) { + png_ptr->rgb_to_gray_red_coeff = (png_uint_16)(((png_uint_32)y_red * + 32768)/w); + png_ptr->rgb_to_gray_green_coeff = (png_uint_16)(((png_uint_32)y_green + * 32768)/w); + png_ptr->rgb_to_gray_blue_coeff = (png_uint_16)(((png_uint_32)y_blue * + 32768)/w); + } } } #endif |