diff --git a/git-compat-util.h b/git-compat-util.h
index 0c65033481..81f2347b27 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -779,7 +779,8 @@ extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1);
 extern char *xgetcwd(void);
 extern FILE *fopen_for_writing(const char *path);
 
-#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), (alloc) * sizeof(*(x)))
+#define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
+#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 
 static inline char *xstrdup_or_null(const char *str)
 {
diff --git a/wrapper.c b/wrapper.c
index 52001789de..32c6c609da 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -152,6 +152,9 @@ void *xcalloc(size_t nmemb, size_t size)
 {
 	void *ret;
 
+	if (unsigned_mult_overflows(nmemb, size))
+		die("data too large to fit into virtual memory space");
+
 	memory_limit_check(size * nmemb, 0);
 	ret = calloc(nmemb, size);
 	if (!ret && (!nmemb || !size))