Constrain value range of lj_ir_kptr() to unsigned 32 bit pointers.

Thanks to Peter Cawley.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/lj_obj.h b/src/lj_obj.h
index 059eb132..25da9455 100644
--- a/src/lj_obj.h
+++ b/src/lj_obj.h
@@ -843,12 +843,16 @@ static LJ_AINLINE void setlightudV(TValue *o, void *p)
 #endif
 
 #if LJ_FR2
-#define setcont(o, f)           ((o)->u64 = (uint64_t)(uintptr_t)(void *)(f))
+#define contptr(f)              ((void *)(f))
+#define setcont(o, f)           ((o)->u64 = (uint64_t)(uintptr_t)contptr(f))
 #elif LJ_64
+#define contptr(f) \
+  ((void *)(uintptr_t)(uint32_t)((intptr_t)(f) - (intptr_t)lj_vm_asm_begin))
 #define setcont(o, f) \
   ((o)->u64 = (uint64_t)(void *)(f) - (uint64_t)lj_vm_asm_begin)
 #else
-#define setcont(o, f)           setlightudV((o), (void *)(f))
+#define contptr(f)              ((void *)(f))
+#define setcont(o, f)           setlightudV((o), contptr(f))
 #endif
 
 #define tvchecklive(L, o) \