1 files changed, 6 insertions, 3 deletions
diff --git a/miasm/jitter/arch/JitCore_x86.c b/miasm/jitter/arch/JitCore_x86.c
index f6e2d6d0..d32f4d17 100644
--- a/miasm/jitter/arch/JitCore_x86.c
+++ b/miasm/jitter/arch/JitCore_x86.c
@@ -489,7 +489,7 @@ PyObject* vm_set_mem(JitCpu *self, PyObject* args)
        Py_ssize_t py_length;
 
        char * buffer;
-       uint64_t size;
+       Py_ssize_t pysize;
        uint64_t addr;
        int ret;
 
@@ -501,10 +501,13 @@ PyObject* vm_set_mem(JitCpu *self, PyObject* args)
        if(!PyBytes_Check(py_buffer))
 	       RAISE(PyExc_TypeError,"arg must be bytes");
 
-       size = PyBytes_Size(py_buffer);
+       pysize = PyBytes_Size(py_buffer);
+       if (pysize < 0) {
+	       RAISE(PyExc_TypeError,"Python error");
+       }
        PyBytes_AsStringAndSize(py_buffer, &buffer, &py_length);
 
-       ret = vm_write_mem(&(((VmMngr*)self->pyvm)->vm_mngr), addr, buffer, size);
+       ret = vm_write_mem(&(((VmMngr*)self->pyvm)->vm_mngr), addr, buffer, pysize);
        if (ret < 0)
 	       RAISE(PyExc_TypeError,"arg must be str");