l2: handle complete clone fail in l2_flood

vlib_buffer_clone(...) may not manage to produce any buffer clones at
all.

vlib_buffer_clone_256 should not smash the original buffer reference
count if no clones are produced.

Type: fix

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I14d9d53637a220485c7a0036cfc75a4149b264ea

diff --git a/src/vlib/buffer_funcs.h b/src/vlib/buffer_funcs.h
index 7103227..98ee205 100644 (file)
--- a/src/vlib/buffer_funcs.h
+++ b/src/vlib/buffer_funcs.h
@@ -1208,11 +1208,11 @@ vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
       d->next_buffer = src_buffer;
     }
   vlib_buffer_advance (s, head_end_offset);
-  s->ref_count = n_buffers;
+  s->ref_count = n_buffers ? n_buffers : s->ref_count;
   while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
     {
       s = vlib_get_buffer (vm, s->next_buffer);
-      s->ref_count = n_buffers;
+      s->ref_count = n_buffers ? n_buffers : s->ref_count;
     }
 
   return n_buffers;

diff --git a/src/vnet/l2/l2_flood.c b/src/vnet/l2/l2_flood.c
index 10e0877..b5eb5fe 100644 (file)
--- a/src/vnet/l2/l2_flood.c
+++ b/src/vnet/l2/l2_flood.c
@@ -230,6 +230,13 @@ VLIB_NODE_FN (l2flood_node) (vlib_main_t * vm,
              if (PREDICT_FALSE (n_cloned != n_clones))
                {
                  b0->error = node->errors[L2FLOOD_ERROR_REPL_FAIL];
+                 /* Worst-case, no clones, consume the original buf */
+                 if (n_cloned == 0)
+                   {
+                     ci0 = bi0;
+                     member = msm->members[thread_index][0];
+                     goto use_original_buffer;
+                   }
                }
 
              /*
@@ -284,6 +291,7 @@ VLIB_NODE_FN (l2flood_node) (vlib_main_t * vm,
              member = msm->members[thread_index][0];
            }
 
+       use_original_buffer:
          /*
           * the last clone that might go to a BVI
           */
@@ -306,8 +314,6 @@ VLIB_NODE_FN (l2flood_node) (vlib_main_t * vm,
              clib_memcpy_fast (t->src, h0->src_address, 6);
              clib_memcpy_fast (t->dst, h0->dst_address, 6);
            }
-
-
          /* Forward packet to the current member */
          if (PREDICT_FALSE (member->flags & L2_FLOOD_MEMBER_BVI))
            {