php-fpm crashed when curl or file_get_contents req

My server is nginx + php-fpm

code below will cause the bug

file_get_contents('https://github.com');

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://github.com");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HEADER, 0);
$output = curl_exec($ch); //crash here
curl_close($ch);

the webpage shows 502 error

nginx log is

[error] 2656#0: *541 recv() failed (104: Connection reset by peer) while reading response header from upstream

fpm log is

Jul 03 00:37:37.619903 [NOTICE] fpm_got_signal(), line 48: received SIGCHLD

Jul 03 00:37:37.619926 [WARNING] fpm_children_bury(), line 215: child 3567 (pool default) exited on signal 11 SIGSEGV (core dumped) after 417.576755 seconds from start

Jul 03 00:37:37.620807 [NOTICE] fpm_children_make(), line 352: child 4193 (pool default) started

If the request url starts with http:// , everything is OK .

php configure command is

'./configure' '--prefix=/www/nginx_php-5.2.17' '--with-config-file-path=/www/nginx_php-5.2.17/etc' '--with-mysql=/www/mysql' '--with-iconv=/usr' '--with-freetype-dir' '--with-jpeg-dir' '--with-png-dir' '--with-zlib' '--with-libxml-dir=/usr' '--enable-xml' '--disable-rpath' '--enable-discard-path' '--enable-inline-optimization' '--with-curl' '--enable-mbregex' '--enable-mbstring' '--with-mcrypt=/usr' '--with-gd' '--enable-gd-native-ttf' '--with-openssl' '--with-mhash' '--enable-ftp' '--enable-sockets' '--enable-zip' '--enable-fastcgi' '--enable-fpm' '--with-fpm-conf=/www/etc/php-fpm.conf'

Try adding these two:

curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);

They will prevent the verification of the SSL certificate. This might be the issue as the verification might fail. Unless it's mandatory to verify the source, always add these 2 lines when downloading data with cURL.

PS: Not sure this will help you though.