Added check for small ZEMD_MM_SEG_SIZE

diff --git a/Zend/zend_alloc.c b/Zend/zend_alloc.c
index c17abc4dc008ae894490db1c4f4f415f82d11c0b..09ef8aa0aa535a2d76539eb2c0617cfdcb6616a8 100644 (file)
--- a/Zend/zend_alloc.c
+++ b/Zend/zend_alloc.c
@@ -1117,6 +1117,9 @@ ZEND_API zend_mm_heap *zend_mm_startup(void)
                if (zend_mm_low_bit(seg_size) != zend_mm_high_bit(seg_size)) {
                        fprintf(stderr, "ZEND_MM_SEG_SIZE must be a power of two\n");
                        exit(255);
+               } else if (seg_size < ZEND_MM_ALIGNED_SEGMENT_SIZE + ZEND_MM_ALIGNED_HEADER_SIZE) {
+                       fprintf(stderr, "ZEND_MM_SEG_SIZE is too small\n");
+                       exit(255);
                }
        } else {
                seg_size = ZEND_MM_SEG_SIZE;