Bug #60629 [NEW]: memory corruption when web server closed the fcgi fd(?)
From:
Operating system: Debian Squeeze
PHP version: 5.3.9RC4
Package: FPM related
Bug Type: Bug
Bug description:memory corruption when web server closed the fcgi fd(?)
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;
}
--
Edit bug report at https://bugs.php.net/bug.php?id=60629&edit=1
--
Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=60629&r=trysnapshot54
Try a snapshot (PHP 5.3): https://bugs.php.net/fix.php?id=60629&r=trysnapshot53
Try a snapshot (trunk): https://bugs.php.net/fix.php?id=60629&r=trysnapshottrunk
Fixed in SVN: https://bugs.php.net/fix.php?id=60629&r=fixed
Fixed in SVN and need be documented: https://bugs.php.net/fix.php?id=60629&r=needdocs
Fixed in release: https://bugs.php.net/fix.php?id=60629&r=alreadyfixed
Need backtrace: https://bugs.php.net/fix.php?id=60629&r=needtrace
Need Reproduce Script: https://bugs.php.net/fix.php?id=60629&r=needscript
Try newer version: https://bugs.php.net/fix.php?id=60629&r=oldversion
Not developer issue: https://bugs.php.net/fix.php?id=60629&r=support
Expected behavior: https://bugs.php.net/fix.php?id=60629&r=notwrong
Not enough info: https://bugs.php.net/fix.php?id=60629&r=notenoughinfo
Submitted twice: https://bugs.php.net/fix.php?id=60629&r=submittedtwice
register_globals: https://bugs.php.net/fix.php?id=60629&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=60629&r=php4
Daylight Savings: https://bugs.php.net/fix.php?id=60629&r=dst
IIS Stability: https://bugs.php.net/fix.php?id=60629&r=isapi
Install GNU Sed: https://bugs.php.net/fix.php?id=60629&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=60629&r=float
No Zend Extensions: https://bugs.php.net/fix.php?id=60629&r=nozend
MySQL Configuration Error: https://bugs.php.net/fix.php?id=60629&r=mysqlcfg
Thread (8 messages)
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