Fixed bug #40770 (Apache child exits when PHP memory limit reached)

NEWS

@@ -18,6 +18,7 @@ PHP                                                                        NEWS
 - Fixed a thread safety issue in gd gif read code (Nuno, Roman Nemecek)
 - Fixed CVE-2007-1001, GD wbmp used with invalid image size (Pierre)
 - Fixed bug #40784 (Case sensivity in constructor's fallback). (Tony)
+- Fixed bug #40770 (Apache child exits when PHP memory limit reached). (Dmitry)
 - Fixed bug #40764 (line thickness not respected for horizontal and vertical 
   lines). (Pierre)
 - Fixed bug #40754 (added substr() & substr_replace() overflow checks). (Ilia)

Zend/tests/bug40770.phpt

@@ -0,0 +1,15 @@
+--TEST--
+Bug #40770 Apache child exits when PHP memory limit reached 
+--INI--
+memory_limit=64M
+--FILE--
+<?php
+ini_set('display_errors',true);
+$mb=148;
+$var = '';
+for ($i=0; $i<=$mb; $i++) {
+        $var.= str_repeat('a',1*1024*1024);
+}
+?>
+--EXPECTF--
+Fatal error: Allowed memory size of 67108864 bytes exhausted%s(tried to allocate %d bytes) in %sbug40770.php on line 6

Zend/zend_alloc.c

@@ -1714,6 +1714,9 @@ realloc_segment:
 		segment_copy = (zend_mm_segment *) ((char *)mm_block - ZEND_MM_ALIGNED_SEGMENT_SIZE);
 		if (segment_size < true_size ||
 		    heap->real_size + segment_size - segment_copy->size > heap->limit) {
+			if (ZEND_MM_IS_FREE_BLOCK(next_block)) {
+				zend_mm_add_to_free_list(heap, (zend_mm_free_block *) next_block);
+			}
 #if ZEND_MM_CACHE
 			zend_mm_free_cache(heap);
 #endif