Fix UB signed integer overflow in js_math_imul

- Use uint32_t arithmetics and Standard conformant conversion to
  avoid UB in js_math_imul.
- add builtin tests
- use specific object directories for SAN targets

1 files changed, 7 insertions, 5 deletions

diff --git a/quickjs.c b/quickjs.c
index 2c1ac6b..6a34940 100644
--- a/quickjs.c
+++ b/quickjs.c
@@ -43092,14 +43092,16 @@ static double js_math_fround(double a)
 static JSValue js_math_imul(JSContext *ctx, JSValueConst this_val,
                             int argc, JSValueConst *argv)
 {
-    int a, b;
+    uint32_t a, b, c;
+    int32_t d;
 
-    if (JS_ToInt32(ctx, &a, argv[0]))
+    if (JS_ToUint32(ctx, &a, argv[0]))
         return JS_EXCEPTION;
-    if (JS_ToInt32(ctx, &b, argv[1]))
+    if (JS_ToUint32(ctx, &b, argv[1]))
         return JS_EXCEPTION;
-    /* purposely ignoring overflow */
-    return JS_NewInt32(ctx, a * b);
+    c = a * b;
+    memcpy(&d, &c, sizeof(d));
+    return JS_NewInt32(ctx, d);
 }
 
 static JSValue js_math_clz32(JSContext *ctx, JSValueConst this_val,