Last week I updated my Drupal 7.15 to 7.21. Immediately I found that some images that worked fine before the update were broken. I did a lot of searching and trying, found out that it could be a core bug that appeared in version 7.20 and apparently has been inherited in some way by 7.21. I have applied patches and fixes:
#1934568: Allow sites using the 'image_allow_insecure_derivatives' variable to have partial protection from the Drupal 7.20 security issue
#1923554: New anti-DoS measure breaks for some file URIs
#1923936: Responsive images and styles module doesn't work with Drupal 7.20
Still I can't use some image styles. At first it seemed there was a pattern when generating the image style from large images, but even that is not consistent as some appear ok and some don't (with similar size/dimension).
Example: using thumbnail style, the image tag appears like the source is broken, I can only see the Alternative text. If I click "view image" on the Alternative text to see the broken image, I get the error:Fatal error: Allowed memory size of 94371840 bytes exhausted (tried to allocate 4320 bytes) in /home/.../modules/system/image.gd.inc on line 237
It is definitely NOT a problem with PHP memory, because the same image was ok before the update.
It is definitely NOT a problem with file/folder permissions, I have tried all possible combinations. The styles are not created.
Environment:
Apache Web server
PHP 5.3.13
This is a major problem as I can't use these images in galleries in my website. Please, help!