Bug #64187 [Opn->Fbk]: CGI/FastCGI truncates input to modulo 4GB

Edit report at https://bugs.php.net/bug.php?id=64187&edit=1 ID: 64187 Updated by: yohgaki@php.net Reported by: nachms+php at gmail dot com Summary: CGI/FastCGI truncates input to modulo 4GB -Status: Open +Status: Feedback Type: Bug Package: Streams related Operating System: Linux PHP Version: 5.4.11 Block user comment: N Private report: N New Comment: PHP 5.5 and up should be able to handle large input. Do you still have this issue? Previous Comments: ------------------------------------------------------------------------ [2013-02-20 03:47:08] nachms+php at gmail dot com Hi payden, Thanks for the info and your test script. I'll try to run some tests myself when I get a chance. No worries about hardcoded data, you'll see the C files I provided hardcode data as well. Regarding the comment breaking, did you test to ensure things are not broken with the original un-commented PHP code? Also, the PHP I provided actually contains a typo, fclose($tfp); should be fclose($ifp); Perhaps this is why things are being left open? As for the 4GB limitation, indeed 99% of users would not care. However I created a file-sharing website using PHP, and ran into this ridiculous limitation. For the time being, I'm using a slight variation on my patch here on my Apache+FastCGI+PHP5-CGI site. I have yet to play with the PHP5-FPM SAPI though, but hope to thanks to your script. ------------------------------------------------------------------------ [2013-02-20 03:44:06] payden at paydensutherland dot com Also, I didn't mention, my program hangs waiting for FPM to close the connection with the count_bytes line commented out. With the count_bytes line, this is my output: FCGI_STDOUT: ====== X-Powered-By: PHP/5.4.11 Content-type: text/html Array ( [USER] => www-data [HOME] => /var/www [FCGI_ROLE] => RESPONDER [QUERY_STRING] => test [REQUEST_METHOD] => PUT [CONTENT_TYPE] => [CONTENT_LENGTH] => 4296015872 [SCRIPT_NAME] => /index.php [REQUEST_URI] => / [DOCUMENT_URI] => /index.php [DOCUMENT_ROOT] => /home/payden [SERVER_PROTOCOL] => HTTP/1.1 [GATEWAY_INTERFACE] => CGI/1.1 [SCRIPT_FILENAME] => /home/payden/index.php [SERVER_NAME] => test.localhost.net [HTTP_HOST] => test.localhost.net [REMOTE_ADDR] => 127.0.0.1 [REMOTE_PORT] => 12312 [SERVER_ADDR] => 127.0.0.1 [SERVER_PORT] => 80 [PHP_SELF] => /index.php [REQUEST_TIME_FLOAT] => 1361331663.522 [REQUEST_TIME] => 1361331663 [argv] => Array ( [0] => test ) [argc] => 1 ) Amount Read: 2147483647 ====== FCGI_END_REQUEST Connection closed. Actually sent: 2155288000 So, it finishes cleanly with stock 5.4.11, but the number of bytes actually sent before FPM closes the connection varies and the PHP side of things always reports max 32-bit signed int as amount read. ------------------------------------------------------------------------ [2013-02-20 03:31:20] payden at paydensutherland dot com Hey nachms, I played around a bit more and it seems that the count_bytes comment does in fact break things in FPM. I don't know why I didn't notice it the other day. It seems that FPM doesn't clean things up properly or terminate the connection even though it does recv all the bytes sent across the wire. It behaves fine during the send and will output to FCGI_STDOUT records while it's still reading FCGI_STDIN and I had the PHP script report the amount of bytes read after each call to fread(). It does in fact read all the bytes, but as I said, FPM does not close the connection after it sends FCGI_END_REQUEST. I also notice that it left some junk in the reserved bytes of the FCGI_END_REQUEST body which is definitely broken behavior. Anywho, I might see if I can come up with a fix sometime. I'm sure it's not high priority for the PHP folks. It's not often one sends 4GB+ of data over FastCGI to PHP. Now, no judging me on this because it is definitely hacky and thrown together and buggy, but I'll throw the C I've been using to test this up on my server. http://paydensutherland.com/php- 64187.c. Maybe you can do something useful with it. The FCGI_PARAMS are hard coded, so you'll need to point the DOCUMENT_ROOT and SCRIPT_FILENAME and such to actual paths on your system. Cheers. ------------------------------------------------------------------------ [2013-02-19 05:34:17] nachms+php at gmail dot com payden, thanks for the info. It's nice to know that the fix works properly with FPM builds as well, and even on 32-bit! I wouldn't mind testing that out myself. Can you post your C FCGI client? Thanks. Allowing others to easily test and report if they can reproduce the problem or not in other cases may help the PHP developers too (or not, no idea how important the votes and statistics are). ------------------------------------------------------------------------ [2013-02-19 05:20:31] payden at paydensutherland dot com Hey, I did a little testing and have some findings to share. I believe your fix works perfectly fine with php-fpm and it does not in fact need to be bounded for fcgi_read to work correctly. I wanted to duplicate your initial test over fpm and see what happened. With the the bounding in place, I got some weird results with fpm. The PHP script stopped reading and finished executing at exactly 2147483647 bytes. (signed 32-bit int max) When I commented the MIN() out and rebuilt, the script read the entirety of the 4296015872 bytes I sent it and reported reading that amount. I used the same PHP code you used for the test and a hacked together C FCGI client. I am using a 32-bit build of PHP. I don't know if any of this information is useful for you, but I was bored and would kind of like to start watching bugs and getting involved a little bit. Let me know if I'm going about it the wrong way! ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=64187 -- Edit this bug report at https://bugs.php.net/bug.php?id=64187&edit=1