Bug #80907 [Opn]: Seg fault with pcntl_alarm() when triggered while waiting on IO

Edit report at https://bugs.php.net/bug.php?id=80907&edit=1 ID: 80907 User updated by: tobias dot nyholm at gmail dot com Reported by: tobias dot nyholm at gmail dot com Summary: Seg fault with pcntl_alarm() when triggered while waiting on IO Status: Open Type: Bug Package: PCNTL related Operating System: OSX PHP Version: 7.4.16 Block user comment: N Private report: N New Comment: Great! Im happy the bug is fixed in later patch versions. Here is the crash log. --------------- Process: php [15272] Path: /usr/local/Cellar/php/7.4.10/bin/php Identifier: php Version: 0 Code Type: X86-64 (Native) Parent Process: zsh [24880] Responsible: phpstorm [2201] User ID: 501 Date/Time: 2021-03-25 23:24:11.746 +0100 OS Version: Mac OS X 10.15.7 (19H2) Report Version: 12 Anonymous UUID: 187FC819-8EA4-6935-FB12-CD56C0275BA2 Sleep/Wake UUID: A66D0A37-1DD8-4E1D-93EE-D2E20EEFB870 Time Awake Since Boot: 260000 seconds Time Since Wake: 2800 seconds System Integrity Protection: enabled Crashed Thread: 0 Dispatch queue: com.apple.main-thread Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: EXC_I386_GPFLT Exception Note: EXC_CORPSE_NOTIFY Termination Signal: Segmentation fault: 11 Termination Reason: Namespace SIGNAL, Code 0xb Terminating Process: exc handler [15272] Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 php 0x000000010ee3e203 ZEND_HANDLE_EXCEPTION_SPEC_HANDLER + 265 1 pcov.so 0x00000001129559cd php_pcov_execute_ex + 157 2 blackfire.so 0x0000000112f3c0fb bf_zend_execute + 43 3 php 0x000000010ee24bf6 ZEND_DO_FCALL_SPEC_RETVAL_UNUSED_HANDLER + 403 4 pcov.so 0x00000001129559cd php_pcov_execute_ex + 157 5 blackfire.so 0x0000000112f3c0fb bf_zend_execute + 43 6 php 0x000000010ee0948f zend_execute + 352 7 php 0x000000010edcc38d zend_execute_scripts + 277 8 php 0x000000010ed74985 php_execute_script + 482 9 php 0x000000010ee5316e do_cli + 3833 10 php 0x000000010ee520d3 main + 1211 11 libdyld.dylib 0x00007fff72755cc9 start + 1 Thread 0 crashed with X86 Thread State (64-bit): rax: 0x0000000000000080 rbx: 0x0000000000000006 rcx: 0x6972637320656874 rdx: 0x0000000000000024 rdi: 0x0000000112a16100 rsi: 0x0000000000000006 rbp: 0x00007ffee113a9b0 rsp: 0x00007ffee113a990 r8: 0x0000000112a16101 r9: 0x0000000112a161a0 r10: 0x0000000112b0cd80 r11: 0x0000000000000246 r12: 0x0000000112b0b0c0 r13: 0x0000000112955bf8 r14: 0x0000000112a16100 r15: 0x00000000ffffffff rip: 0x000000010ee3e203 rfl: 0x0000000000010206 cr2: 0x000000010ee3e0fa Logical CPU: 4 Error Code: 0x00000000 Trap Number: 13 Binary Images: (Removed because they are not interesting) External Modification Summary: Calls made by other processes targeting this process: task_for_pid: 0 thread_create: 0 thread_set_state: 0 Calls made by this process: task_for_pid: 0 thread_create: 0 thread_set_state: 0 Calls made by all processes on this machine: task_for_pid: 964101 thread_create: 0 thread_set_state: 0 VM Region Summary: ReadOnly portion of Libraries: Total=521.4M resident=0K(0%) swapped_out_or_unallocated=521.4M(100%) Writable regions: Total=452.8M written=0K(0%) resident=0K(0%) swapped_out=0K(0%) unallocated=452.8M(100%) VIRTUAL REGION REGION TYPE SIZE COUNT (non-coalesced) =========== ======= ======= Kernel Alloc Once 8K 1 MALLOC 80.1M 23 MALLOC guard page 24K 5 MALLOC_MEDIUM (reserved) 360.0M 3 reserved VM address space (unallocated) Memory Tag 250 2048K 1 STACK GUARD 56.0M 1 Stack 8192K 1 VM_ALLOCATE 2052K 1 VM_ALLOCATE (reserved) 192K 1 reserved VM address space (unallocated) __DATA 7331K 198 __DATA_CONST 1628K 39 __LINKEDIT 394.9M 78 __OBJC_RO 32.3M 1 __OBJC_RW 1908K 2 __TEXT 126.6M 190 __UNICODE 564K 1 shared memory 12K 3 =========== ======= ======= TOTAL 1.0G 549 TOTAL, minus reserved VM space 713.1M 549 Previous Comments: ------------------------------------------------------------------------ [2021-03-25 22:21:39] danack@php.net Hi Tobias, I think I can reproduce, but on an older version. Do you have a crash log in ~/Library/Logs/DiagnosticReports/ ? That should contain a stacktrace. If one doesn't appear there, running the code with sudo dtruss php debug.php might be a magic invocation that makes one appear. Please post the stacktrace if you can. ------------------------------------------------------------------------ [2021-03-25 21:40:13] tobias dot nyholm at gmail dot com Thank you for trying to reproduce. I've installed PHP with homebrew. The bug is present on PHP 7.4.10 and 7.4.14. Not on PHP 8.0.1 --------- ❯ php -v PHP 7.4.14 (cli) (built: Jan 5 2021 14:30:27) ( NTS ) Copyright (c) The PHP Group Zend Engine v3.4.0, Copyright (c) Zend Technologies with Zend OPcache v7.4.14, Copyright (c), by Zend Technologies with blackfire v1.48.1~mac-x64-non_zts74, https://blackfire.io, by Blackfire ❯ php alarm.php .[1] 33291 segmentation fault php alarm.php ❯ php8 -v PHP 8.0.1 (cli) (built: Jan 7 2021 17:26:28) ( NTS ) Copyright (c) The PHP Group Zend Engine v4.0.1, Copyright (c) Zend Technologies with Xdebug v3.0.2, Copyright (c) 2002-2021, by Derick Rethans with Zend OPcache v8.0.1, Copyright (c), by Zend Technologies ❯ php8 alarm.php .PHP Fatal error: Uncaught RuntimeException: Maximum execution time reached in /workspace/alarm.php:5 Stack trace: #0 /workspace/alarm.php(13): {closure}(14, Array) #1 /workspace/alarm.php(21): Worker->work() #2 {main} thrown in /workspace/alarm.php on line 5 Fatal error: Uncaught RuntimeException: Maximum execution time reached in /workspace/alarm.php on line 5 RuntimeException: Maximum execution time reached in /workspace/alarm.php on line 5 Call Stack: 0.0003 464296 1. {main}() /workspace/alarm.php:0 0.0005 469392 2. Worker->work() /workspace/alarm.php:21 2.0052 469896 3. {closure:/workspace/alarm.php:4-6}(14, ['signo' => 14, 'errno' => 0, 'code' => 0]) /workspace/alarm.php:13 ------------------------------------------------------------------------ [2021-03-25 20:55:11] dc dot link at yahoo dot fr Was unable to reproduce it with Mac Intel and M1 with and without debug. Does it occur all the time and was it build from source or is it homebrew/macports ? ------------------------------------------------------------------------ [2021-03-25 14:44:29] tobias dot nyholm at gmail dot com Description: ------------ When using pcntl_alarm() and the alarm is triggered when waiting for IO inside a class, I get a "42064 segmentation fault". If the for loop is executing in the global namespace, everything is fine. Test script: --------------- <?php pcntl_async_signals(true); pcntl_signal(SIGALRM, function () { throw new \RuntimeException('Maximum execution time reached'); }); pcntl_alarm(2); class Worker { public function work() { for ($i = 0; $i< 10; $i++) { echo '.'; sleep(5); } } } $worker = new Worker(); $worker->work(); echo "end"; Expected result: ---------------- .PHP Fatal error: Uncaught RuntimeException: Maximum execution time reached in /Users/tobias/Workspace/PHPStorm/bref/alarm.php:5 Stack trace: #0 /Users/tobias/Workspace/PHPStorm/bref/alarm.php(13): {closure}(14, Array) #1 /Users/tobias/Workspace/PHPStorm/bref/alarm.php(21): Worker->work() #2 {main} thrown in /Users/tobias/Workspace/PHPStorm/bref/alarm.php on line 5 Actual result: -------------- ❯ php alarm.php .[1] 41920 segmentation fault php alarm.php ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=80907&edit=1