diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 294779c..95d79dd 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3025,7 +3025,7 @@
                 return -TARGET_EINVAL;
             }
             results = lock_user(VERIFY_WRITE, optval_addr, len, 1);
-            if (!results) {
+            if (!results && len > 0) {
                 return -TARGET_EFAULT;
             }
             lv = len;