From 2c8bf41f4adf425afc668b77c2a792abcdd98c5b Mon Sep 17 00:00:00 2001
From: jiangheng <jiangheng14@huawei.com>
Date: Thu, 17 Oct 2024 19:16:55 +0800
Subject: [PATCH] control: call epoll_ctl delete fd when fd close

---
 src/lstack/core/lstack_control_plane.c | 8 ++++++++
 src/lstack/core/lstack_lwip.c          | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/src/lstack/core/lstack_control_plane.c b/src/lstack/core/lstack_control_plane.c
index 11f5129..bf34693 100644
--- a/src/lstack/core/lstack_control_plane.c
+++ b/src/lstack/core/lstack_control_plane.c
@@ -778,6 +778,12 @@ void control_server_thread(void *arg)
         }
 
         if ((evt_array.events & EPOLLERR) || (evt_array.events & EPOLLHUP)) {
+            /*
+             * if app call fork and child process inherits the fd,
+             * close fd cannot ensure that fd is removed from the epoll,
+             * so epoll_ctl_del need to be called.
+             */
+            posix_api->epoll_ctl_fn(epfd, EPOLL_CTL_DEL, evt_array.data.fd, NULL);
             posix_api->close_fn(evt_array.data.fd);
             continue;
         }
@@ -795,6 +801,8 @@ void control_server_thread(void *arg)
             }
         } else {
             if (handle_stat_request(evt_array.data.fd) < 0) {
+                /* same as the comment above */
+                posix_api->epoll_ctl_fn(epfd, EPOLL_CTL_DEL, evt_array.data.fd, NULL);
                 posix_api->close_fn(evt_array.data.fd);
             }
         }
diff --git a/src/lstack/core/lstack_lwip.c b/src/lstack/core/lstack_lwip.c
index cb0964b..bb261d2 100644
--- a/src/lstack/core/lstack_lwip.c
+++ b/src/lstack/core/lstack_lwip.c
@@ -185,6 +185,10 @@ int do_lwip_init_sock(int32_t fd)
         return 0;
     }
 
+    if (sock->recv_ring != NULL || sock->send_ring != NULL) {
+        LSTACK_LOG(ERR, LSTACK, "socket(%d) not close but open again?\n", fd);
+    }
+
     reset_sock_data(sock);
 
     sock->recv_ring = gazelle_ring_create_fast("sock_recv", SOCK_RECV_RING_SIZE, RING_F_SP_ENQ | RING_F_SC_DEQ);
-- 
2.33.0