1 #include "phpdbg_sigsafe.h"
2 #include "phpdbg.h"
3
ZEND_EXTERN_MODULE_GLOBALS(phpdbg)4 ZEND_EXTERN_MODULE_GLOBALS(phpdbg)
5
6 #define STR(x) #x
7 #define EXP_STR(x) STR(x)
8
9 static void* zend_mm_mem_alloc(zend_mm_storage *storage, size_t size, size_t alignment) {
10
11 if (EXPECTED(size <= PHPDBG_SIGSAFE_MEM_SIZE && !PHPDBG_G(sigsafe_mem).allocated)) {
12 PHPDBG_G(sigsafe_mem).allocated = 1;
13 return (void *) (((size_t) PHPDBG_G(sigsafe_mem).mem & ~(alignment - 1)) + alignment);
14 }
15
16 zend_quiet_write(PHPDBG_G(io)[PHPDBG_STDERR].fd, ZEND_STRL("Tried to allocate more than " EXP_STR(PHPDBG_SIGSAFE_MEM_SIZE) " bytes from stack memory in signal handler ... bailing out of signal handler\n"));
17
18 if (*EG(bailout)) {
19 LONGJMP(*EG(bailout), FAILURE);
20 }
21
22 zend_quiet_write(PHPDBG_G(io)[PHPDBG_STDERR].fd, ZEND_STRL("Bailed out without a bailout address in signal handler!\n"));
23
24 return NULL;
25 }
26
zend_mm_mem_free(zend_mm_storage * storage,void * ptr,size_t size)27 static void zend_mm_mem_free(zend_mm_storage *storage, void *ptr, size_t size) {
28 }
29
phpdbg_set_sigsafe_mem(char * buffer)30 void phpdbg_set_sigsafe_mem(char *buffer) {
31 phpdbg_signal_safe_mem *mem = &PHPDBG_G(sigsafe_mem);
32 const zend_mm_handlers phpdbg_handlers = {
33 zend_mm_mem_alloc,
34 zend_mm_mem_free,
35 NULL,
36 NULL,
37 };
38
39 mem->mem = buffer;
40 mem->allocated = 0;
41
42 mem->heap = zend_mm_startup_ex(&phpdbg_handlers, NULL, 0);
43
44 mem->old_heap = zend_mm_set_heap(mem->heap);
45 }
46
phpdbg_original_heap_sigsafe_mem(void)47 zend_mm_heap *phpdbg_original_heap_sigsafe_mem(void) {
48 return PHPDBG_G(sigsafe_mem).old_heap;
49 }
50
phpdbg_clear_sigsafe_mem(void)51 void phpdbg_clear_sigsafe_mem(void) {
52 zend_mm_set_heap(phpdbg_original_heap_sigsafe_mem());
53 PHPDBG_G(sigsafe_mem).mem = NULL;
54 }
55
phpdbg_active_sigsafe_mem(void)56 zend_bool phpdbg_active_sigsafe_mem(void) {
57 return !!PHPDBG_G(sigsafe_mem).mem;
58 }
59
