The error is coming from Mage_Catalog_Model_Product_Option_Type_File but it is not interpreted in _getValidatorErrors(). The error happens repeatedly for certain users and not other users.
In $fileInfo = $upload->getFileInfo($file);, the error is 7. For example:
Array
(
[name] => YU XIA.jpg
[type] =>
[tmp_name] =>
[error] => 7
[size] =>
[options] => Array
(
[ignoreNoFile] =>
[useByteString] => 1
[magicFile] =>
[detectInfos] => 1
)
[validated] =>
[received] =>
[filtered] =>
[validators] => Array
(
[0] => Zend_Validate_File_Upload
)
[title] => YU XIA.jpg
)
Looking at the source code, I deduce that the uploaded file is saved in the system tmp directory, /tmp. When PHP cannot write the file in /tmp, it throws this error. So, the error occurs way before the file is Rename (as a filter in Zend_File_Transfer), or moved to the ../media/custom_options/quote/. Compare to this error, which happened when the file is saved in the /tmp:
Array
(
[name] => kiat1a.JPG
[type] => image/jpeg
[tmp_name] => /tmp/phpivaSBH
[error] => 0
[size] => 360225
[options] => Array
(
[ignoreNoFile] =>
[useByteString] => 1
[magicFile] =>
[detectInfos] => 1
)
[validated] =>
[received] =>
[filtered] =>
[validators] => Array
(
[0] => Zend_Validate_File_Upload
)
[title] => kiat1a.JPG
)
Resolution
Remove all the temporary image files in /tmp. The file names are prefixed with 'php' as in the above example.
There may be a size constraint on /tmp. This can be easily tested by FTP a sizable file to /tmp. Besure to test all servers in a load balance configuration.
