Re: [PATCH] kmod: don't load module unless req process has CAP_SYS_MODULE

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 15 May 2017 08:10:59 +0200

On Sun, May 14, 2017 at 08:57:34AM -0500, Eric W. Biederman wrote:

quoted

Greg Kroah-Hartman [off-list ref] writes:

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index bcb0f610ee42..6b72528a4636 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c

@@ -2595,7 +2595,7 @@ static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 
                if (!ops) {
 #ifdef CONFIG_MODULES
-                       if (kind[0]) {
+                       if (kind[0] && capable(CAP_NET_ADMIN)) {
                                __rtnl_unlock();
                                request_module("rtnl-link-%s", kind);
                                rtnl_lock();

I don't object to this if the networking developers don't mind the
change in functionality.  They can handle the fallout :)

As I've said in another email, I am pretty sure this can break things.