From 4828f781895696f149965d36cb5c7425c03693e6 Mon Sep 17 00:00:00 2001 From: Joshua Rogers Date: Wed, 22 Oct 2025 01:20:52 +0800 Subject: [PATCH] tcp: apply CLOEXEC to accepted socket, not listener The accept path calls set_cloexec(sd) after accept(). That re-flags the listening socket, which is already CLOEXEC from create_socket_tcp(), and leaves new_sd inheritable. As a result, client-connect and auth scripts spawned after accept can inherit the connected socket and read or write the raw TCP stream. This defeats the stated intent to prevent scripts from accessing the client socket. This bug was found using ZeroPath. Signed-off-by: Joshua Rogers --- src/openvpn/socket.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/openvpn/socket.c b/src/openvpn/socket.c index 40a86fbb..8eac96dd 100644 --- a/src/openvpn/socket.c +++ b/src/openvpn/socket.c @@ -836,7 +836,7 @@ socket_do_accept(socket_descriptor_t sd, struct link_socket_actual *act, const b { /* set socket file descriptor to not pass across execs, so that * scripts don't have access to it */ - set_cloexec(sd); + set_cloexec(new_sd); } return new_sd; } -- 2.51.1