From 2ae0271ada810c06c12755699f0db955fc51061d Mon Sep 17 00:00:00 2001
From: Petr Lautrbach <plautrba@redhat.com>
Date: Thu, 10 Mar 2016 10:19:56 +0100
Subject: [PATCH] socket_address_listen - do not rely on errno

Currently socket_address_listen() calls mac_selinux_bind() to bind a UNIX
socket and checks its return value and errno for EADDRINUSE. This is not
correct. When there's an SELinux context change made for the new socket,
bind() is not the last function called in mac_selinux_bind(). In that
case the last call is setfscreatecon() from libselinux which can change
errno as it uses access() to check if /proc/thread-self is available.
It fails on kernels before 3.17 and errno is set to ENOENT.

It's safe to check only the return value at it's set to -errno.

Cherry-picked from: a0c9496cc826957fe0f3926f619e073f17a9ab4d
Resolves: #1316452
---
 src/shared/socket-label.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/shared/socket-label.c b/src/shared/socket-label.c
index a6289eb50..713e71ba3 100644
--- a/src/shared/socket-label.c
+++ b/src/shared/socket-label.c
@@ -119,7 +119,7 @@ int socket_address_listen(
 
                 r = mac_selinux_bind(fd, &a->sockaddr.sa, a->size);
 
-                if (r < 0 && errno == EADDRINUSE) {
+                if (r == -EADDRINUSE) {
                         /* Unlink and try again */
                         unlink(a->sockaddr.un.sun_path);
                         r = bind(fd, &a->sockaddr.sa, a->size);