From 415b6a7c75d003b90d8a7f02563ab41f1b036c21 Mon Sep 17 00:00:00 2001
From: Dmitry Valter <d-valter@yandex-team.ru>
Date: Mon, 12 Dec 2022 11:43:33 +0000
Subject: bfd: fix bfd udp error enum incompatibility

New BFD UDP errors were no longer compatible with BFD errors. This was causing
out-of-bound reads and ASAN test crashes.

Fix this issue by statically checking if these enums are compatible.

Type: fix
Signed-off-by: Dmitry Valter <d-valter@yandex-team.ru>
Change-Id: I92fddd26270f946bc16ade840c94e5496e2cb88a
---
 src/vnet/bfd/bfd.api   | 51 ++++++++++++++++++++++++++++++++++++++++++++++----
 src/vnet/bfd/bfd_udp.c |  8 ++++++++
 2 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/src/vnet/bfd/bfd.api b/src/vnet/bfd/bfd.api
index f573bc5309a..d3b3ed21a26 100644
--- a/src/vnet/bfd/bfd.api
+++ b/src/vnet/bfd/bfd.api
@@ -359,6 +359,7 @@ autoreply define bfd_udp_auth_deactivate
   bool is_delayed;
 };
 
+/* must be compatible with bfd_error_t */
 counters bfd_udp {
   none {
     severity info;
@@ -366,17 +367,23 @@ counters bfd_udp {
     units "packets";
     description "OK";
   };
-  no_session {
+  bad {
     severity error;
     type counter64;
     units "packets";
-    description "no-session";
+    description "bad packet";
   };
-  bad {
+  disabled {
     severity error;
     type counter64;
     units "packets";
-    description "bad packet";
+    description "bfd packets received on disabled interfaces";
+  };
+  version {
+    severity error;
+    type counter64;
+    units "packets";
+    description "version";
   };
   length {
     severity error;
@@ -384,6 +391,42 @@ counters bfd_udp {
     units "packets";
     description "too short";
   };
+  detect_multi {
+    severity error;
+    type counter64;
+    units "packets";
+    description "detect-multi";
+  };
+  multi_point {
+    severity error;
+    type counter64;
+    units "packets";
+    description "multi-point";
+  };
+  my_disc {
+    severity error;
+    type counter64;
+    units "packets";
+    description "my-disc";
+  };
+  your_disc {
+    severity error;
+    type counter64;
+    units "packets";
+    description "your-disc";
+  };
+  admin_down {
+    severity error;
+    type counter64;
+    units "packets";
+    description "session admin-down";
+  };
+  no_session {
+    severity error;
+    type counter64;
+    units "packets";
+    description "no-session";
+  };
   failed_verification {
     severity error;
     type counter64;
diff --git a/src/vnet/bfd/bfd_udp.c b/src/vnet/bfd/bfd_udp.c
index 37bb102d2d9..2ba43a309d1 100644
--- a/src/vnet/bfd/bfd_udp.c
+++ b/src/vnet/bfd/bfd_udp.c
@@ -42,6 +42,14 @@
 #include <vnet/bfd/bfd_api.h>
 #include <vnet/bfd/bfd.api_enum.h>
 
+#define F(sym, str)                                                           \
+  STATIC_ASSERT ((int) BFD_ERROR_##sym == (int) BFD_UDP_ERROR_##sym,          \
+		 "BFD error enums mismatch");
+foreach_bfd_error (F)
+#undef F
+  STATIC_ASSERT ((int) BFD_N_ERROR <= (int) BFD_UDP_N_ERROR,
+		 "BFD error enum sizes mismatch");
+
 typedef struct
 {
   bfd_main_t *bfd_main;
-- 
cgit 1.2.3-korg