~ubuntu-branches/ubuntu/natty/php5/natty-updates

Description: fix denial of service and possible information disclosure

 via exif integer overflow

Origin: upstream, http://svn.php.net/viewvc?view=revision&revision=319535

Bug: https://bugs.php.net/bug.php?id=60150

 

Index: php5-5.3.8.0/ext/exif/exif.c

===================================================================

--- php5-5.3.8.0.orig/ext/exif/exif.c   2011-12-12 15:13:43.006064337 -0500

+++ php5-5.3.8.0/ext/exif/exif.c        2011-12-12 15:13:58.910064186 -0500

@@ -2874,11 +2874,11 @@

                offset_val = php_ifd_get32u(dir_entry+8, ImageInfo->motorola_intel);

                /* If its bigger than 4 bytes, the dir entry contains an offset. */

                value_ptr = offset_base+offset_val;

-               if (offset_val+byte_count > IFDlength || value_ptr < dir_entry) {

+               if (byte_count > IFDlength || offset_val > IFDlength-byte_count || value_ptr < dir_entry) {

                        /* It is important to check for IMAGE_FILETYPE_TIFF

                         * JPEG does not use absolute pointers instead its pointers are

                         * relative to the start of the TIFF header in APP1 section. */

-                       if (offset_val+byte_count>ImageInfo->FileSize || (ImageInfo->FileType!=IMAGE_FILETYPE_TIFF_II && ImageInfo->FileType!=IMAGE_FILETYPE_TIFF_MM && ImageInfo->FileType!=IMAGE_FILETYPE_JPEG)) {

+                       if (byte_count > ImageInfo->FileSize || offset_val>ImageInfo->FileSize-byte_count || (ImageInfo->FileType!=IMAGE_FILETYPE_TIFF_II && ImageInfo->FileType!=IMAGE_FILETYPE_TIFF_MM && ImageInfo->FileType!=IMAGE_FILETYPE_JPEG)) {

                                if (value_ptr < dir_entry) {

                                        /* we can read this if offset_val > 0 */

                                        /* some files have their values in other parts of the file */