Fix bug #63327

Use ZEND_MM_ALIGNED_SIZE for the extra size information.
I don't have a relevant system to test, but this should fix the
issue as long as required alignment is detected correctly.

Author: nikic

NEWS

@@ -2,6 +2,10 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 8.1.0beta2
 
+- MySQLnd:
+  . Fixed bug #63327 (Crash (Bus Error) in mysqlnd due to wrong alignment).
+    (Nikita)
+
 - Opcache:
   . Fixed Bug #81255 (Memory leak in PHPUnit with functional JIT)
   . Fixed Bug #80959 (infinite loop in building cfg during JIT compilation)

ext/mysqlnd/mysqlnd_alloc.c

@@ -61,9 +61,10 @@ PHPAPI const char * mysqlnd_debug_std_no_trace_funcs[] =
 #define __zend_orig_lineno   0
 #endif
 
-#define REAL_SIZE(s) (collect_memory_statistics? (s) + sizeof(size_t) : (s))
-#define REAL_PTR(p) (collect_memory_statistics && (p)? (((char *)(p)) - sizeof(size_t)) : (p))
-#define FAKE_PTR(p) (collect_memory_statistics && (p)? (((char *)(p)) + sizeof(size_t)) : (p))
+#define EXTRA_SIZE ZEND_MM_ALIGNED_SIZE(sizeof(size_t))
+#define REAL_SIZE(s) (collect_memory_statistics? (s) + EXTRA_SIZE : (s))
+#define REAL_PTR(p) (collect_memory_statistics && (p)? (((char *)(p)) - EXTRA_SIZE) : (p))
+#define FAKE_PTR(p) (collect_memory_statistics && (p)? (((char *)(p)) + EXTRA_SIZE) : (p))
 
 /* {{{ _mysqlnd_emalloc */
 static void * _mysqlnd_emalloc(size_t size MYSQLND_MEM_D)