File 0136-erts-Fix-bug-when-detecting-bad-dist-message.patch of Package erlang
From 0ee0af9d6114054cb38fce2377678682181b6788 Mon Sep 17 00:00:00 2001
From: Sverker Eriksson <sverker@erlang.org>
Date: Fri, 29 Sep 2017 19:32:18 +0200
Subject: [PATCH 2/2] erts: Fix bug when detecting bad dist message
We can't just leave it in queue with dist_ext=NULL.
Two symptoms seen:
1. 'receive' trying to deref dist_ext as NULL.
2. GC think it's a term and put THE_NON_VALUE in root set.
---
erts/emulator/beam/erl_message.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/erts/emulator/beam/erl_message.c b/erts/emulator/beam/erl_message.c
index cdd771ef7d..de9f16d088 100644
--- a/erts/emulator/beam/erl_message.c
+++ b/erts/emulator/beam/erl_message.c
@@ -564,14 +564,11 @@ erts_msg_attached_data_size_aux(ErtsMessage *msg)
sz = erts_decode_dist_ext_size(msg->data.dist_ext);
if (sz < 0) {
- /* Bad external; remove it */
- if (is_not_nil(ERL_MESSAGE_TOKEN(msg))) {
- ErlHeapFragment *heap_frag;
- heap_frag = erts_dist_ext_trailer(msg->data.dist_ext);
- erts_cleanup_offheap(&heap_frag->off_heap);
- }
- erts_free_dist_ext_copy(msg->data.dist_ext);
- msg->data.dist_ext = NULL;
+ /* Bad external
+ * We leave the message intact in this case as it's not worth the trouble
+ * to make all callers remove it from queue. It will be detected again
+ * and removed from message queue later anyway.
+ */
return 0;
}
--
2.14.2