Bug #79907 [PATCH]: exif_read_data() corrupt EXIF header: maximum directory nesting level reached

Edit report at https://bugs.php.net/bug.php?id=79907&edit=1 ID: 79907 Patch added by: nikic@php.net Reported by: php at lho dot io Summary: exif_read_data() corrupt EXIF header: maximum directory nesting level reached Status: Open Type: Bug Package: EXIF related Operating System: Linux PHP Version: 7.4.8 Block user comment: N Private report: N New Comment: The following pull request has been associated: Patch Name: Make MAX_IFD_NESTING_LEVEL an actual nesting level On GitHub: https://github.com/php/php-src/pull/5976 Patch: https://github.com/php/php-src/pull/5976.patch Previous Comments: ------------------------------------------------------------------------ [2020-08-12 08:01:39] nikic@php.net Looks like ifd_nesting_level only ever gets incremented, so MAX_IFD_NESTING_LEVEL is not really a "nesting level" but rather MAX_NUMBER_OF_IFD_TAGS. I suspect that is not what was intended. ------------------------------------------------------------------------ [2020-08-09 15:10:28] lookingdown at mail dot com ext/exif/exif.c line 69 #define MAX_IFD_NESTING_LEVEL 150 changing this to #define MAX_IFD_NESTING_LEVEL 300 Should cover most EXIF value scenarios, f.ex. Panasonic GH4 with added GPS info have 244 entries. After value change of MAX_IFD_NESTING_LEVEL to desired value f.ex. 300 in exif.c recompile module and replace exif.so in extension dir of PHP installation. Tested with 7.3 from github src repo. Seems to do the trick, the problem have nothing to do with inherent limitations of PHP as suggested elsewhere, just this restriction/limitation hardcoded in extension exif. ------------------------------------------------------------------------ [2020-07-28 12:29:13] php at lho dot io Description: ------------ Might be the same problem as in https://bugs.php.net/bug.php?id=78083, I'm no EXIF expert. In that case, let the reference photo be another datapoint. When reading exif data from an image (which works fine in exiftool), I get the error: PHP Warning: exif_read_data(DSCF1362.jpg): corrupt EXIF header: maximum directory nesting level reached in /home/leo/Downloads/test/script.php on line 2 Geodata is missing in the result. Most images taken with the same camera (Fuji X-T30) and edited with darktable work, but I have 8 images where this error happens. Upon request, I can provide additional images. Link to the image causing this specific error: https://gofile.io/d/A42LUr Test script: --------------- <?php $exif = exif_read_data('DSCF1362.jpg', 0, true); foreach ($exif as $key => $section) { foreach ($section as $name => $val) { echo "$key.$name: "; print_r($val); echo "<br />\n"; } } ?> Expected result: ---------------- Should read all EXIF data correctly Actual result: -------------- Error message and missing data ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79907&edit=1