Bug #76542 [NEW]: Memory leak during verify_peer_name validation of a SAN SSL certificate

From: php at lvl dot fastmail dot com Operating system: Ubuntu 18.04 PHP version: 7.2.7 Package: OpenSSL related Bug Type: Bug Bug description:Memory leak during verify_peer_name validation of a SAN SSL certificate Description: ------------ Originally discovered here: https://github.com/reactphp/http-client/issues/134. Verified with version 7.2.7-1+ubuntu18.04.1+deb.sury.org+1 on Ubuntu 18.04, libssl 1.1.0g. There's a memory leak in PHP's validation of SSL certificates when that SSL certificate contains SAN entries. Since nearly every real world SSL certificate uses SAN, this means every long-running PHP script that acts as a HTTPS client will eventually run out of memory. To reproduce, first create a self-signed certificate with SAN: openssl req \ -newkey rsa:2048 \ -x509 \ -nodes \ -keyout server.key \ -new \ -out server.crt \ -subj /CN=127.0.0.1 \ -reqexts SAN \ -extensions SAN \ -config <(cat /etc/ssl/openssl.cnf \ <(printf '[SAN]\nsubjectAltName=DNS:127.0.0.1,DNS:127.0.0.2')) \ -sha256 \ -days 3650 Then configure for example nginx to use this certificate: server { listen 443 ssl; ssl_certificate /etc/nginx/server.crt; ssl_certificate_key /etc/nginx/server.key; return 201; } Finally run the test script below and observe using "top" that PHP's memory usage is quickly increasing. Calls to memory_get_usage() will *not* show signs of the leak though. Running this test with a SSL certificate without the subjectAltName entry will *not* trigger the memory leak. Add ['verify_peer_name' => false] to the ssl context options and there will *not* be a leak. Test script: --------------- <?php $options = [ 'ssl' => [ 'verify_peer' => false ] ]; while (true) { $response = file_get_contents('https://127.0.0.1', false, stream_context_create($options)); } -- Edit bug report at https://bugs.php.net/bug.php?id=76542&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=76542&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=76542&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=76542&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=76542&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=76542&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=76542&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=76542&r=needscript Try newer version: https://bugs.php.net/fix.php?id=76542&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=76542&r=support Expected behavior: https://bugs.php.net/fix.php?id=76542&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=76542&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=76542&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=76542&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=76542&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=76542&r=dst IIS Stability: https://bugs.php.net/fix.php?id=76542&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=76542&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=76542&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=76542&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=76542&r=mysqlcfg