diff -r -U 3 libpng-0.95/png.h libpng-0.95p/png.h
--- libpng-0.95/png.h Sat Mar 29 04:59:50 1997
+++ libpng-0.95p/png.h Tue Aug 3 21:50:20 2004
@@ -360,6 +360,11 @@
typedef png_info FAR * png_infop;
typedef png_info FAR * FAR * png_infopp;
+/* Maximum positive integer used in PNG is (2^31)-1 */
+#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
+#define PNG_UINT_32_MAX (~((png_uint_32)0))
+#define PNG_SIZE_MAX (~((png_size_t)0))
+
/* These describe the color_type field in png_info. */
/* color type masks */
#define PNG_COLOR_MASK_PALETTE 1
@@ -1370,6 +1375,8 @@
PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
#endif /* PNG_BIG_ENDIAN_GET_SUPPORTED */
+PNG_EXTERN png_uint_32 png_get_uint_31 PNGARG((png_structp png_ptr,
+ png_bytep buf));
/* Initialize png_ptr struct for reading, and allocate any other memory
* (old interface - NOT DLL EXPORTED) */
diff -r -U 3 libpng-0.95/pngconf.h libpng-0.95p/pngconf.h
--- libpng-0.95/pngconf.h Sat Mar 29 02:35:00 1997
+++ libpng-0.95p/pngconf.h Tue Aug 3 21:51:25 2004
@@ -239,6 +239,13 @@
#define PNG_WRITE_SWAP_ALPHA_SUPPORTED
#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+#ifndef PNG_USER_WIDTH_MAX
+# define PNG_USER_WIDTH_MAX 1000000L
+#endif
+#ifndef PNG_USER_HEIGHT_MAX
+# define PNG_USER_HEIGHT_MAX 1000000L
+#endif
+
/* These are currently experimental features */
#undef PNG_READ_16_TO_8_ACCURATE_SHIFT_SUPPORTED /* very little testing */
#undef PNG_READ_COMPOSITE_NODIV_SUPPORTED /* very little testing */
diff -r -U 3 libpng-0.95/pngpread.c libpng-0.95p/pngpread.c
--- libpng-0.95/pngpread.c Sat Mar 29 02:35:18 1997
+++ libpng-0.95p/pngpread.c Tue Aug 3 21:50:21 2004
@@ -131,7 +131,7 @@
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
- png_ptr->push_length = png_get_uint_32(chunk_length);
+ png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
@@ -449,6 +449,11 @@
png_size_t new_max;
png_bytep old_buffer;
+ if (png_ptr->save_buffer_size > PNG_SIZE_MAX -
+ (png_ptr->current_buffer_size + 256))
+ {
+ png_error(png_ptr, "Potential overflow of save_buffer");
+ }
new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
old_buffer = png_ptr->save_buffer;
png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr, new_max);
@@ -491,8 +496,7 @@
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
- png_ptr->push_length = png_get_uint_32(chunk_length);
-
+ png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
diff -r -U 3 libpng-0.95/pngread.c libpng-0.95p/pngread.c
--- libpng-0.95/pngread.c Sat Mar 29 02:35:22 1997
+++ libpng-0.95p/pngread.c Tue Aug 3 21:50:21 2004
@@ -155,7 +155,7 @@
png_uint_32 length;
png_read_data(png_ptr, chunk_length, 4);
- length = png_get_uint_32(chunk_length);
+ length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
@@ -363,7 +363,7 @@
png_crc_finish(png_ptr, 0);
png_read_data(png_ptr, chunk_length, 4);
- png_ptr->idat_size = png_get_uint_32(chunk_length);
+ png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
@@ -539,7 +539,7 @@
do
{
png_read_data(png_ptr, chunk_length, 4);
- length = png_get_uint_32(chunk_length);
+ length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
diff -r -U 3 libpng-0.95/pngrutil.c libpng-0.95p/pngrutil.c
--- libpng-0.95/pngrutil.c Sat Mar 29 05:43:38 1997
+++ libpng-0.95p/pngrutil.c Tue Aug 3 21:50:21 2004
@@ -11,6 +11,14 @@
#define PNG_INTERNAL
#include "png.h"
+png_uint_32 /* PRIVATE */
+png_get_uint_31(png_structp png_ptr, png_bytep buf)
+{
+ png_uint_32 i = png_get_uint_32(buf);
+ if (i > PNG_UINT_31_MAX)
+ png_error(png_ptr, "PNG unsigned integer out of range.\n");
+ return (i);
+}
#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
/* Grab an unsigned 32-bit integer from a buffer in big endian format. */
png_uint_32
@@ -659,7 +667,8 @@
/* Should be an error, but we can cope with it */
png_warning(png_ptr, "Missing PLTE before tRNS");
}
- else if (length > png_ptr->num_palette)
+ if (length > (png_uint_32)png_ptr->num_palette ||
+ length > 256)
{
png_warning(png_ptr, "Incorrect tRNS chunk length");
png_crc_finish(png_ptr, length);
diff -r -U 3 libpng-0.95/pngset.c libpng-0.95p/pngset.c
--- libpng-0.95/pngset.c Sat Mar 29 07:07:34 1997
+++ libpng-0.95p/pngset.c Tue Aug 3 21:50:21 2004
@@ -82,6 +82,9 @@
if (info_ptr == NULL)
return;
+ if (width > PNG_USER_WIDTH_MAX || height > PNG_USER_HEIGHT_MAX)
+ png_error(png_ptr, "image size exceeds user limits in IHDR");
+
info_ptr->width = width;
info_ptr->height = height;
info_ptr->bit_depth = (png_byte)bit_depth;