diff --git a/src/core/platform/tests/test-route.c b/src/core/platform/tests/test-route.c
index 2d39cb3789..858382674c 100644
--- a/src/core/platform/tests/test-route.c
+++ b/src/core/platform/tests/test-route.c
@@ -1390,12 +1390,17 @@ again_table:
         rr->protocol = _rr_rand_choose_u8(nmtst_get_rand_uint32());
 
 #define IPTOS_TOS_MASK 0x1E
+#define INET_DSCP_MASK 0xFC
 
 again_tos:
     rr->tos = _rr_rand_choose_u8(nmtst_get_rand_uint32());
+
     if (rr->addr_family == AF_INET && rr->tos & ~IPTOS_TOS_MASK)
         goto again_tos;
 
+    if (rr->tos & ~INET_DSCP_MASK)
+        goto again_tos;
+
     if (_rule_check_kernel_support(platform, FRA_IP_PROTO))
         rr->ip_proto = _rr_rand_choose_u8(nmtst_get_rand_uint32());