Bug #77358 [Opn->Dup]: random Segmentation fault (core dumped)

Edit report at https://bugs.php.net/bug.php?id=77358&edit=1 ID: 77358 Updated by: nikic@php.net Reported by: kinoute at gmail dot com Summary: random Segmentation fault (core dumped) -Status: Open +Status: Duplicate Type: Bug Package: PDO MySQL Operating System: Ubuntu 16.04.5 PHP Version: 7.3.0 Block user comment: N Private report: N New Comment: Given the use of persistent PDO connections and the efree() segfault during shutdown, this is very likely a duplicate of bug #77289, which will be fixed in PHP 7.3.2. Previous Comments: ------------------------------------------------------------------------ [2019-01-13 18:47:22] kinoute at gmail dot com Some update. I was about to make a little script were I get the same backtrace on gdb every single time I run the php script. Running MySQL 5.7.24, with a "test" table as followed, with a datetime(6) column. It seems to happen when using the "UPDATE" mysql function. No problem with a simple SELECT. CREATE TABLE test ( id int(11) NOT NULL, date datetime(6) NOT NULL, poster_id int(11) NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci; INSERT INTO test (id, date, poster_id) VALUES (1, '2019-01-17 01:40:35.123456', 3); PHP Script: <?php $dbh = ""; $dsn = 'mysql:host=localhost;dbname=testphp73'; // Set options $options = [ PDO::ATTR_PERSISTENT => true, PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION ]; // Create a new PDO instanace try { $dbh = new PDO($dsn, "root", "password", $options); } // Catch any errors catch (PDOException $e) { $this->error = $e->getMessage(); } $stmt = $dbh->prepare("UPDATE test SET poster_id = 4 WHERE id = 1"); // no problem // $stmt = $dbh->prepare("SELECT * FROM test WHERE id = 1"); $stmt->execute(); gdb backtrace with the UPDATE function: (gdb) run test.php Starting program: /usr/bin/php test.php [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". [Inferior 1 (process 6354) exited with code 01] (gdb) b exit Breakpoint 1 at 0x7ffff5d0a030: file exit.c, line 104. (gdb) run test.php Starting program: /usr/bin/php test.php [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Breakpoint 1, __GI_exit (status=1) at exit.c:104 104 exit.c: No such file or directory. (gdb) bt #0 __GI_exit (status=1) at exit.c:104 #1 0x00005555556319ed in ?? () #2 0x00005555557c2e1d in _efree () #3 0x00007ffff2d4fea7 in ?? () from /usr/lib/php/20180731/mysqlnd.so #4 0x00007ffff2d4af4f in ?? () from /usr/lib/php/20180731/mysqlnd.so #5 0x00007ffff2d4f641 in ?? () from /usr/lib/php/20180731/mysqlnd.so #6 0x00007ffff2d4e0b9 in ?? () from /usr/lib/php/20180731/mysqlnd.so #7 0x00007ffff2d4be04 in ?? () from /usr/lib/php/20180731/mysqlnd.so #8 0x00007ffff2d4bf4e in ?? () from /usr/lib/php/20180731/mysqlnd.so #9 0x00007fffed601ee4 in ?? () from /usr/lib/php/20180731/pdo_mysql.so #10 0x00007ffff2b28d0c in ?? () from /usr/lib/php/20180731/pdo.so #11 0x00007ffff2b2cbaa in ?? () from /usr/lib/php/20180731/pdo.so #12 0x00005555557fc6ce in ?? () #13 0x00005555557f9371 in zend_hash_graceful_reverse_destroy () #14 0x00005555557e885e in ?? () #15 0x0000555555787662 in php_module_shutdown () #16 0x000055555564282a in ?? () #17 0x00007ffff5cf0830 in __libc_start_main (main=0x5555556423a0, argc=2, argv=0x7fffffffe5c8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe5b8) at ../csu/libc-start.c:291 #18 0x0000555555642939 in _start () (gdb) gdb backtrace when using SELECT function: (gdb) run test.php Starting program: /usr/bin/php test.php [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". [Inferior 1 (process 6387) exited normally] (gdb) b exit Breakpoint 1 at 0x7ffff5d0a030: file exit.c, line 104. (gdb) run test.php Starting program: /usr/bin/php test.php [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Breakpoint 1, __GI_exit (status=0) at exit.c:104 104 exit.c: No such file or directory. (gdb) bt #0 __GI_exit (status=0) at exit.c:104 #1 0x000055555564252d in ?? () #2 0x00007ffff5cf0830 in __libc_start_main (main=0x5555556423a0, argc=2, argv=0x7fffffffe5c8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe5b8) at ../csu/libc-start.c:291 #3 0x0000555555642939 in _start () (gdb) ------------------------------------------------------------------------ [2018-12-27 13:31:06] kinoute at gmail dot com Description: ------------ It happens on a VPN running Ubuntu 16.04.5 & PHP 7.3.0 (upgraded from 7.2.13). I'm getting at random intervals Segfault errors on some scripts. I was able to catch a segfault running my script through gdb. Here is the output backtrace: (gdb) run checkwin.php Starting program: /usr/bin/php checkwin.php [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0x00005555557c2d3a in _efree () (gdb) bt #0 0x00005555557c2d3a in _efree () #1 0x00007ffff2d4fea7 in ?? () from /usr/lib/php/20180731/mysqlnd.so #2 0x00007ffff2d4af4f in ?? () from /usr/lib/php/20180731/mysqlnd.so #3 0x00007ffff2d4f641 in ?? () from /usr/lib/php/20180731/mysqlnd.so #4 0x00007ffff2d4e0b9 in ?? () from /usr/lib/php/20180731/mysqlnd.so #5 0x00007ffff2d4be04 in ?? () from /usr/lib/php/20180731/mysqlnd.so #6 0x00007ffff2d4bf4e in ?? () from /usr/lib/php/20180731/mysqlnd.so #7 0x00007fffed601ee4 in ?? () from /usr/lib/php/20180731/pdo_mysql.so #8 0x00007ffff2b28d0c in ?? () from /usr/lib/php/20180731/pdo.so #9 0x00007ffff2b2cbaa in ?? () from /usr/lib/php/20180731/pdo.so #10 0x00005555557fc60e in ?? () #11 0x00005555557f92b1 in zend_hash_graceful_reverse_destroy () #12 0x00005555557e879e in ?? () #13 0x00005555557875e2 in php_module_shutdown () #14 0x00005555556427fa in ?? () #15 0x00007ffff5cf0830 in __libc_start_main (main=0x555555642370, argc=2, argv=0x7fffffffe5b8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe5a8) at ../csu/libc-start.c:291 #16 0x0000555555642909 in _start () (gdb) I can also see segfaults in /var/log/syslog: Dec 27 12:05:15 vps12833 kernel: [ 1122.000275] php[1975]: segfault at 7f4d49000000 ip 000055a75bf88d3a sp 00007fff1fb200f0 error 4 in php7.3[55a75bd1a000+3eb000] ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=77358&edit=1