Fix mishandling of incoming socket buffer. It must be set on the listening socket not the accepted socket.

src/local.c

@@ -205,6 +205,14 @@ create_and_bind(const char *addr, const char *port)
             }
         }
 
+        if (tcp_incoming_sndbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
+        }
+
+        if (tcp_incoming_rcvbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
+        }
+
         s = bind(listen_sock, rp->ai_addr, rp->ai_addrlen);
         if (s == 0) {
             /* We managed to bind successfully! */
@@ -1406,14 +1414,6 @@ accept_cb(EV_P_ ev_io *w, int revents)
     setsockopt(serverfd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt));
 #endif
 
-    if (tcp_incoming_sndbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
-    }
-
-    if (tcp_incoming_rcvbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
-    }
-
     server_t *server = new_server(serverfd);
     server->listener = listener;
 

src/redir.c

@@ -201,6 +201,14 @@ create_and_bind(const char *addr, const char *port)
             LOGI("tcp tproxy mode enabled");
         }
 
+        if (tcp_incoming_sndbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
+        }
+
+        if (tcp_incoming_rcvbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
+        }
+
         s = bind(listen_sock, rp->ai_addr, rp->ai_addrlen);
         if (s == 0) {
             /* We managed to bind successfully! */
@@ -759,14 +767,6 @@ accept_cb(EV_P_ ev_io *w, int revents)
     setsockopt(serverfd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt));
 #endif
 
-    if (tcp_incoming_sndbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
-    }
-
-    if (tcp_incoming_rcvbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
-    }
-
     int index                    = rand() % listener->remote_num;
     struct sockaddr *remote_addr = listener->remote_addr[index];
 

src/server.c

@@ -620,6 +620,14 @@ create_and_bind(const char *host, const char *port, int mptcp)
             }
         }
 
+        if (tcp_incoming_sndbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
+        }
+
+        if (tcp_incoming_rcvbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
+        }
+
         // Enable out-of-tree mptcp
         if (mptcp == 1) {
             int i = 0;
@@ -1769,14 +1777,6 @@ accept_cb(EV_P_ ev_io *w, int revents)
     setsockopt(serverfd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt));
 #endif
 
-    if (tcp_incoming_sndbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
-    }
-
-    if (tcp_incoming_rcvbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
-    }
-
     setnonblocking(serverfd);
 
     server_t *server = new_server(serverfd, listener);

src/tunnel.c

@@ -166,6 +166,14 @@ create_and_bind(const char *addr, const char *port)
             }
         }
 
+        if (tcp_incoming_sndbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
+        }
+
+        if (tcp_incoming_rcvbuf > 0) {
+            setsockopt(listen_sock, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
+        }
+
         s = bind(listen_sock, rp->ai_addr, rp->ai_addrlen);
         if (s == 0) {
             /* We managed to bind successfully! */
@@ -725,14 +733,6 @@ accept_cb(EV_P_ ev_io *w, int revents)
     setsockopt(serverfd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt));
 #endif
 
-    if (tcp_incoming_sndbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_SNDBUF, &tcp_incoming_sndbuf, sizeof(int));
-    }
-
-    if (tcp_incoming_rcvbuf > 0) {
-        setsockopt(serverfd, SOL_SOCKET, SO_RCVBUF, &tcp_incoming_rcvbuf, sizeof(int));
-    }
-
     int index                    = rand() % listener->remote_num;
     struct sockaddr *remote_addr = listener->remote_addr[index];