Edit report at https://bugs.php.net/bug.php?id=60629&edit=1

 ID:                 60629
 Updated by:         f...@php.net
 Reported by:        phpbugs at oops dot mooo dot com
 Summary:            memory corruption when web server closed the fcgi
                     fd(?)
-Status:             Assigned
+Status:             Feedback
 Type:               Bug
 Package:            FPM related
 Operating System:   Debian Squeeze
 PHP Version:        5.3.9RC4
 Assigned To:        fat
 Block user comment: N
 Private report:     N

 New Comment:

Can you please test and validate the attached patch please ?

thx
++ jerome


Previous Comments:
------------------------------------------------------------------------
[2012-01-03 18:02:55] f...@php.net

The following patch has been added/updated:

Patch Name: fpm-bugs-60629.patch
Revision:   1325613774
URL:        
https://bugs.php.net/patch-display.php?bug=60629&patch=fpm-bugs-60629.patch&revision=1325613774

------------------------------------------------------------------------
[2012-01-03 12:13:34] f...@php.net

it's on my todo list. I'll try to take time to look at this bugs this week.

++ jerome

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[2012-01-03 12:12:09] larue...@php.net

fat, could you plz look at this? thanks

------------------------------------------------------------------------
[2011-12-30 23:40:43] phpbugs at oops dot mooo dot com

I think it might've been introduced in this commit (~line 270).

http://svn.php.net/viewvc/php/php-src/tags/php_5_3_9RC4/sapi/fpm/fpm/fpm_main.c?r1=317894&r2=317897

It looks like write() might have the same problem, since it returns a ssize_t 
that's casted to size_t.

Fix might be to use ssize_t instead?

------------------------------------------------------------------------
[2011-12-30 23:12:00] phpbugs at oops dot mooo dot com

Description:
------------
I tried php5.3.9RC4 today and got a few core dumps.

I think b)fcgi_flush() returns false, making fcgi_write return -1. Then 
sapi_cgibin_single_write will make it positive because ret is unsigned in c). 
As a result, the comparison in d) will fail.

In debugger it looks like PHP is looping over open_packet() in an infinite 
loop. Each time out_pos gets increased a little. Finally, after overwriting the 
whole stack, it will SIGSEGV.

=== 
https://svn.php.net/repository/php/php-src/tags/php_5_3_9RC4/sapi/fpm/fpm/fastcgi.c
 ===
int fcgi_write(fcgi_request *req, fcgi_request_type type, const char *str, int 
len)
{
        int limit, rest;

        if (len <= 0) {
                return 0;
        }

        if (req->out_hdr && req->out_hdr->type != type) {
                close_packet(req);
        }

        /* Optimized version */
        limit = sizeof(req->out_buf) - (req->out_pos - req->out_buf);
        if (!req->out_hdr) {
                limit -= sizeof(fcgi_header);
                if (limit < 0) limit = 0;
        }

        if (len < limit) {
                if (!req->out_hdr) {
                        open_packet(req, type);
                }
                memcpy(req->out_pos, str, len);
                req->out_pos += len;
        } else if (len - limit < sizeof(req->out_buf) - sizeof(fcgi_header)) {
                if (!req->out_hdr) {
a)                      open_packet(req, type);
                }
                if (limit > 0) {
                        memcpy(req->out_pos, str, limit);
                        req->out_pos += limit;
                }
                if (!fcgi_flush(req, 0)) {
b)                      return -1;
                }

=== 
https://svn.php.net/repository/php/php-src/tags/php_5_3_9RC4/sapi/fpm/fpm/fpm_main.c
 ===
static inline size_t sapi_cgibin_single_write(const char *str, uint str_length 
TSRMLS_DC)
{
c)      size_t ret;

        /* sapi has started which means everyhting must be send through fcgi */
        if (fpm_is_running) {
                fcgi_request *request = (fcgi_request*) SG(server_context);
                ret = fcgi_write(request, FCGI_STDOUT, str, str_length);
d)              if (ret <= 0) {
                        return 0;
                }
                return ret;
        }



------------------------------------------------------------------------



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