nat: fix nat44_ed set_session_limit crash

Setting session limit should return error for unknown fib.
Optimize max_translations_per_fib expanding and drop unnecessary
trailing fib entry.

Type: fix
Change-Id: Ie7d2b363ade48f53598faa617a49cce7b2db6400
Signed-off-by: Vladislav Grishenko <themiron@yandex-team.ru>

diff --git a/src/plugins/nat/nat44-ed/nat44_ed.c b/src/plugins/nat/nat44-ed/nat44_ed.c
index 5eee893..08e5777 100644 (file)
--- a/src/plugins/nat/nat44-ed/nat44_ed.c
+++ b/src/plugins/nat/nat44-ed/nat44_ed.c
@@ -3240,16 +3240,12 @@ nat44_set_session_limit (u32 session_limit, u32 vrf_id)
 {
   snat_main_t *sm = &snat_main;
   u32 fib_index = fib_table_find (FIB_PROTOCOL_IP4, vrf_id);
-  u32 len = vec_len (sm->max_translations_per_fib);
 
-  if (len <= fib_index)
-    {
-      vec_validate (sm->max_translations_per_fib, fib_index + 1);
-
-      for (; len < vec_len (sm->max_translations_per_fib); len++)
-       sm->max_translations_per_fib[len] = sm->max_translations_per_thread;
-    }
+  if (~0 == fib_index)
+    return -1;
 
+  vec_validate_init_empty (sm->max_translations_per_fib, fib_index,
+                          sm->max_translations_per_thread);
   sm->max_translations_per_fib[fib_index] = session_limit;
   return 0;
 }

diff --git a/test/test_nat44_ed.py b/test/test_nat44_ed.py
index 323249e..d4dd4be 100644 (file)
--- a/test/test_nat44_ed.py
+++ b/test/test_nat44_ed.py
@@ -2939,10 +2939,13 @@ class TestNAT44EDMW(TestNAT44ED):
 
         limit = 5
 
-        # 2 interfaces pg0, pg1 (vrf10, limit 1 tcp session)
-        # non existing vrf_id makes process core dump
+        # 2 interfaces pg0, pg1 (vrf10, limit 5 tcp sessions)
         self.vapi.nat44_set_session_limit(session_limit=limit, vrf_id=10)
 
+        # expect error when bad is specified
+        with self.vapi.assert_negative_api_retval():
+            self.vapi.nat44_set_session_limit(session_limit=limit, vrf_id=20)
+
         self.nat_add_inside_interface(inside)
         self.nat_add_inside_interface(inside_vrf10)
         self.nat_add_outside_interface(outside)