Topic: PHP 7.0 Zend Segfault
Hi all,
I've run into a recent issue with an old app we have and I'm kind of stuck. The code hasn't been modified in a LONG time and it just stopped working for no apparent reason.
In the app, when you submit a POST request to a certain part it triggers a segfault and the FPM child process exits. I ran a stack trace on the process and I see the following.
12:18:41 lstat("PATH/library/Zend/Config.php", 0x7ffeab808380) = -1 ENOENT (No such file or directory)
12:18:41 lstat("PATH/application/models/Zend/Config.php", 0x7ffeab808380) = -1 ENOENT (No such file or directory)
12:18:41 lstat("PATH/application/forms/Zend/Config.php", 0x7ffeab808380) = -1 ENOENT (No such file or directory)
12:18:41 lstat("PATH/application/plugins/Zend/Config.php", 0x7ffeab808380) = -1 ENOENT (No such file or directory)
12:18:41 fcntl(3, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0
12:18:41 fcntl(3, F_SETLK, {l_type=F_UNLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0
12:18:41 stat("PATH/Zend/Config.php", {st_mode=S_IFREG|0644, st_size=12911, ...}) = 0
12:18:41 --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
12:18:41 +++ killed by SIGSEGV +++Next, I produced a core dump of the issue and when I analyze that I see the following.
1313 } while (0);
1314 #endif
1315
1316 if (EXPECTED(heap->free_slot[bin_num] != NULL)) {
1317 zend_mm_free_slot *p = heap->free_slot[bin_num];
1318 heap->free_slot[bin_num] = p->next_free_slot;
1319 return (void*)p;
1320 } else {
1321 return zend_mm_alloc_small_slow(heap, bin_num ZEND_FILE_LINE_RELAY_CC ZEND_FILE_LINE_ORIG_RELAY_CC);
1322 }The app stopped working somewhere around January. It's not used very often so I don't know exactly when it stopped. I do know there have been no code changes to it though.
I can see the following updates to PHP 7.0 occurred recently.
Jan 22 04:21:33 Updated: php70-php.x86_64 7.0.33-16.el7.remi
Jan 24 02:52:00 Updated: php70-php.x86_64 7.0.33-17.el7.remi
Feb 19 01:56:47 Updated: php70-php.x86_64 7.0.33-18.el7.remiI tried downgrading to -17 but that didn't fix it. -16 isn't available in the repo any longer so I couldn't try it.
Any ideas what might cause this?
Thanks!
