Bug #77647 [Opn]: preload: Access violation in zend_mm_shutdown

Edit report at https://bugs.php.net/bug.php?id=77647&edit=1 ID: 77647 Updated by: nikic@php.net Reported by: mberchtold at gmail dot com Summary: preload: Access violation in zend_mm_shutdown Status: Open Type: Bug Package: opcache Operating System: Windows 10 x64 PHP Version: master-Git-2019-02-21 (snap) Block user comment: N Private report: N New Comment: Just want to check back if this issue still exists. A lot of preloading issues have been fixed since this bug report, so maybe the issue is already resolved? Previous Comments: ------------------------------------------------------------------------ [2019-02-21 19:48:45] mberchtold at gmail dot com Description: ------------ With preloading (preloading of zend framework 3, others) enabled, visiting certain urls of the website crashes php-cgi.exe When preloading is disabled, or when no classes are preloaded it does not crash. php master: r82d6759 > php8.dll!zend_mm_shutdown(_zend_mm_heap * heap, int full, int silent) Line 2269 C [Inline Frame] php8.dll!shutdown_memory_manager(int) C php8.dll!php_module_startup(_sapi_module_struct * sf, _zend_module_entry * additional_modules, unsigned int num_additional_modules) Line 2405 C php-cgi.exe!php_cgi_startup(_sapi_module_struct * sapi_module) Line 973 C php-cgi.exe!main(int argc, char * * argv) Line 1921 C [Inline Frame] php-cgi.exe!invoke_main() Line 78 C++ php-cgi.exe!__scrt_common_main_seh() Line 288 C++ kernel32.dll!00007ff81f3b81f4() Unknown ntdll.dll!00007ff82174a251() Unknown zend_mm_shutdown ... Code: /* move all chunks except of the first one into the cache */ p = heap->main_chunk->next; while (p != heap->main_chunk) { ---> zend_mm_chunk *q = p->next; // p is null p->next = heap->cached_chunks; heap->cached_chunks = p; p = q; heap->chunks_count--; heap->cached_chunks_count++; } Locals: + heap 0x0000026899200040 {use_custom_heap=0x00000000 storage=0x0000000000000000 <NULL> size=0x0000000000000000 ...} _zend_mm_heap * + heap->main_chunk 0x0000026899200000 {heap=0x0000026899200040 {use_custom_heap=0x00000000 storage=0x0000000000000000 <NULL> ...} ...} _zend_mm_chunk * + heap->main_chunk->next 0x0000000000000000 <NULL> _zend_mm_chunk * + p 0x0000000000000000 <NULL> _zend_mm_chunk * For some reason, heap->main_chunk->next is NULL which looks unexpected (heap corruption?). Test script: --------------- I don't have a reproducible case other than that it always crashes when accessing a certain url on an internal website. Expected result: ---------------- no crash Actual result: -------------- Unhandled exception thrown: read access violation. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=77647&edit=1