[mesos] branch master updated: Fixed libevent SSL socket shutdown race condition.

[gr...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

grag pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/mesos.git


The following commit(s) were added to refs/heads/master by this push:
     new e8793b2  Fixed libevent SSL socket shutdown race condition.
e8793b2 is described below

commit e8793b2ca92524c76f96c11e4ca52f41f9a8d414
Author: Greg Mann <gr...@mesosphere.io>
AuthorDate: Mon Apr 13 13:41:08 2020 -0700

    Fixed libevent SSL socket shutdown race condition.
    
    This fixes an issue where the functions `shutdown()` and
    `event_callback()` race to access the bufferevent held by
    our libevent SSL socket implementation, leading to a
    CHECK failure.
    
    This race resulted in MESOS-10111, where multiple rapid
    changes in ZK membership led to one master re-linking to
    another multiple times in RECONNECT mode. This causes
    `shutdown()` to be called on the existing socket while
    it's attempting a connection, at which point a failure to
    connect can produce the CHECK failure.
    
    Review: https://reviews.apache.org/r/72354/
---
 3rdparty/libprocess/src/posix/libevent/libevent_ssl_socket.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/3rdparty/libprocess/src/posix/libevent/libevent_ssl_socket.cpp b/3rdparty/libprocess/src/posix/libevent/libevent_ssl_socket.cpp
index dcb6d8e..864802d 100644
--- a/3rdparty/libprocess/src/posix/libevent/libevent_ssl_socket.cpp
+++ b/3rdparty/libprocess/src/posix/libevent/libevent_ssl_socket.cpp
@@ -190,7 +190,9 @@ Try<Nothing, SocketError> LibeventSSLSocketImpl::shutdown(int how)
         CHECK(__in_event_loop__);
         CHECK(self);
 
-        CHECK_NOTNULL(self->bev);
+        if (self->bev == nullptr) {
+          return;
+        }
 
         synchronized (self->bev) {
           Owned<RecvRequest> request;