tor

commit 4d7ce27105dfb7f04ef14a59d098d2f81363298c
parent b5f39955d1ad14295a9ef415d13a8c6bfd25f8b9
Author: Nick Mathewson <nickm@torproject.org>
Date:   Tue, 17 Sep 2019 09:16:53 -0400

Merge branch 'bug31107_041' into bug31107_master

Diffstat:
A
changes/bug31107
 | 
4
++++
M
src/core/or/channeltls.c
 | 
10
+++++++++-

2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/changes/bug31107 b/changes/bug31107
@@ -0,0 +1,4 @@
+  o Minor bugfixes (logging, protocol violations):
+    - Do not log a nonfatal assertion failure when receiving a VERSIONS
+      cell on a connection using the obsolete v1 link protocol. Log a
+      protocol_warn instead. Fixes bug 31107; bugfix on 0.2.4.4-alpha.
diff --git a/src/core/or/channeltls.c b/src/core/or/channeltls.c
@@ -1106,7 +1106,15 @@ channel_tls_handle_cell(cell_t *cell, or_connection_t *conn)
       /* do nothing */
       break;
     case CELL_VERSIONS:
-      tor_fragile_assert();
+      /* A VERSIONS cell should always be a variable-length cell, and
+       * so should never reach this function (which handles constant-sized
+       * cells). But if the connection is using the (obsolete) v1 link
+       * protocol, all cells will be treated as constant-sized, and so
+       * it's possible we'll reach this code.
+       */
+      log_fn(LOG_PROTOCOL_WARN, LD_CHANNEL,
+             "Received unexpected VERSIONS cell on a channel using link "
+             "protocol %d; ignoring.", conn->link_proto);
       break;
     case CELL_NETINFO:
       ++stats_n_netinfo_cells_processed;