com php-src: Fix bug #65873 - Integer overflow in exif_read _data(): ext/exif/exif.c

Commit: eca037a51dd007032c9ef28bd931e02863e6440d Author: Stanislav Malyshev <stas@php.net> Sun, 8 Dec 2013 15:37:35 -0800 Parents: f3230e35221f5d440480de3871416f8d000991df Branches: PHP-5.3 Link: http://git.php.net/?p=php-src.git;a=commitdiff;h=eca037a51dd007032c9ef28bd931e02863e6440d Log: Fix bug #65873 - Integer overflow in exif_read_data() Bugs: https://bugs.php.net/65873 Changed paths: M ext/exif/exif.c Diff: diff --git a/ext/exif/exif.c b/ext/exif/exif.c index 4f67bdd..862e92b 100644 --- a/ext/exif/exif.c +++ b/ext/exif/exif.c @@ -2874,7 +2874,12 @@ static int exif_process_IFD_TAG(image_info_type *ImageInfo, char *dir_entry, cha 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 (byte_count > IFDlength || offset_val > IFDlength-byte_count || value_ptr < dir_entry) { + /* + dir_entry is ImageInfo->file.list[sn].data+2+i*12 + offset_base is ImageInfo->file.list[sn].data-dir_offset + dir_entry - offset_base is dir_offset+2+i*12 + */ + if (byte_count > IFDlength || offset_val > IFDlength-byte_count || value_ptr < dir_entry || offset_val < (size_t)(dir_entry-offset_base)) { /* 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. */