From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Thu, 28 Oct 2021 15:39:42 +0000 (+0200)
Subject: start: check event loop type before closing fd
X-Git-Tag: lxc-5.0.0~60^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a585382b972c25ee8489147d94918d001ef439a7;p=thirdparty%2Flxc.git

start: check event loop type before closing fd

Since this is a union we might otherwise stomp on io_uring mmap()ed
memory.

Fixes: #4016
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---

diff --git a/src/lxc/start.c b/src/lxc/start.c
index 8f7173ec8..1a6046c7a 100644
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -629,7 +629,8 @@ int lxc_poll(const char *name, struct lxc_handler *handler)
 	TRACE("Mainloop is ready");
 
 	ret = lxc_mainloop(&descr, -1);
-	close_prot_errno_disarm(descr.epfd);
+	if (descr.type == LXC_MAINLOOP_EPOLL)
+		close_prot_errno_disarm(descr.epfd);
 	if (ret < 0 || !handler->init_died)
 		goto out_mainloop_console;