Skip image creation when the calculated height or width of the original image is 0

[phamhung77]

Prerequisites

• I have searched for duplicate or closed issues
• I can recreate the issue with all plugins disabled

Describe the issue

When user attaches an image to signature, for example, the image is converted to an inline image, inserted directly to the mail. It's applied the same when an incoming email including an image, when user forwards that email, the image is attached as inline image. Then from the user GUI, a red alert comes up: Connection error. Roundcube error log records an PHP error related to imagecreatetruecolor() function.

Tested on both Chrome and Safari latest version. When it's happening, the email is still sent. But sometimes the body content is not included completely.

What browser(s) are you seeing the problem on?

Chrome

What version of PHP are you using?

v8.3

What version of Roundcube are you using?

v1.6.6

JavaScript errors

No response

PHP errors

PHP Fatal error: Uncaught ValueError: imagecreatetruecolor(): Argument #2 ($height) must be greater than 0 in /var/www/html/roundcubemail-1.6.6/program/lib/Roundcube/rcube_image.php:252
Stack trace:
#0 /var/www/html/roundcubemail-1.6.6/program/lib/Roundcube/rcube_image.php(252): imagecreatetruecolor()
#1 /var/www/html/roundcubemail-1.6.6/program/actions/mail/get.php(101): rcube_image->resize()
#2 /var/www/html/roundcubemail-1.6.6/program/include/rcmail.php(282): rcmail_action_mail_get->run()
#3 /var/www/html/roundcubemail-1.6.6/index.php(278): rcmail->action_handler()
#4 {main}
thrown in /var/www/html/roundcubemail-1.6.6/program/lib/Roundcube/rcube_image.php on line 252

[pabzm]

Thank you for the report!

Can you please provide us with an example email, so that we can try to reproduce the problem?

[alecpl]

Here the image is being resized (probably for a thumbnail). A sample would be nice, full message or the image alone. Looks like we at least need to skip image creation when the calculated height or width of the original image is 0.

ps. GD functions throw such errors since PHP 8.0, it was just a warning before that. So, we might need to handle such errors in other places too.

[phamhung77]

Thank you for replying. The attached images have height or width > 0. However, after digging into the log, I found a conflict with Comodo WAF mod_security rule #212880. Disabling that rule, no more error.

Can you please check that and see why an inline attached image trigger that rule?
Thanks.

[MrSuddenJoy]

Generally logic here should follow well-proven model of ansMail: thats is sth along:

if (($img:SizeOf(Height)) && ($img:SizeOf(Width)) ) {
// do something
} else {
// do sth else.....
}

At least this is what PHP PSRs requires.

[pabzm]

We should make the code not run into that exception, whatever the reason(s) for it may be.

[MrSuddenJoy]

@pabzm what exception you talk about? and why not?

[pabzm]

what exception you talk about? and why not?

The originally reported exception/error. Because we should have proper error handling, that maybe even tells the user what went wrong.

[MrSuddenJoy]

@pabzm Oh I dim now.......

Now, there I see 2 things:

• use super shitty premade classes for this,
• develop your own in-house solution for this.

[alecpl]

Fixed.