preg_match: compilation failed

[schwim]

Hi there everyone,

Over the past couple days, I have converted my website to use the encoding of UTF8, via head code, form enctype and database conversion. Also during this time, php was upgraded from 5.2 to 5.6. I don't know which one(if either) is causing this issue.

I utilize class.upload.php. It has worked great up to this point.

Today, during image upload, I received these errors:

PHP Warning: in file /home/schw/public_html/includes/upload/class.upload.php on line 2945: preg_match(): Compilation failed: invalid range in character class at offset 7
PHP Warning: in file /home/schw/public_html/includes/upload/class.upload.php on line 2999: preg_match(): Compilation failed: invalid range in character class at offset 7
PHP Warning: in file /home/schw/public_html/includes/upload/class.upload.php on line 3017: preg_match(): Compilation failed: invalid range in character class at offset 7

The file I uploaded was Upload.php. During the process, it gets converted to a png with the linknumber with a timestamp, so the converted name would look like 123-45345345.png.

Here's my form:

<form name='image' enctype='multipart/form-data' method='POST' action='/?action=overlord&do=link-image&id=".$link_id."'>
<input type='file' size='50' name='link_image' value='Browse' /><br />
AND<br />
<input type='submit' name='Submit' value=' Upload ' /></form>

Here's the three lines mentioned in class.upload.php:

 if (preg_match("/^([\.-\w]+)\/([\.-\w]+)(.*)$/i", $this->file_src_mime)) {
if (preg_match("/^([\.-\w]+)\/([\.-\w]+)(.*)$/i", $this->file_src_mime)) {
if (preg_match("/^([\.-\w]+)\/([\.-\w]+)(.*)$/i", $this->file_src_mime)) {

The image did upload successfully. These errors are all I saw to let me know something was wrong.

Could someone help me figure out what happened and what I need to do to fix this?

Thanks for your time!

[schwim]

Well, it looks like I might have resolved my own issue. During my Googling, I found a tiny comment on stackexchange that mentioned that 5.5 PHP and later requiring hyphens to be escaped. I know next to nothing about regex, but I do know what both a hyphen and an escape character looks like, so I tried my hand at fixing it, so here's what I altered it to:

 if (preg_match("/^([\.\-\w]+)\/([\.\-\w]+)(.*)$/i", $this->file_src_mime)) {
                            $this->file_src_mime = preg_replace("/^([\.\-\w]+)\/([\.\-\w]+)(.*)$/i", '$1/$2', $this->file_src_mime);
                            $this->log .= '-&nbsp;MIME validated as ' . $this->file_src_mime . '<br />';
                        }

The errors disappeared, so unless someone sees another issue, I think I managed to resolve it.

[sneakyimp]

I'm too tired to try and experiment with your regexes to figure out whether you fixed the problem or whether you got rid of the error message at the expense of its proper function. I can say this: the hypen char (-) has a special meaning when you put it inside square brackets ([]), namely it specifies a range of characters to be matched. E.g. A-Z or 0-9. The basic idea is that A and Z represent a contiguous range of characters and 0 and 9 represent another contiguous range of characters so [0-9] would match any char between zero and nine. My guess is that . and \w do not represent any definable range of contiguous characters. Seems to me the original code should never have worked but its intent was to match a period, a hyphen, or a word. In the 'fixed' code the fact that you escape the hyphen makes it clear that this char is intended as a hyphen to be matched and not to denote a range.

In short, I think you fixed it but you should probably test it if you know how.