Commit 047570fa authored Nov 01, 2017 by Subash Abhinov Kasiviswanathan Committed by Gerrit - the friendly Code Review server Jan 11, 2019

Revert "genetlink: disallow subscribing to unknown mcast groups"



Commit 5ad63005 ("genetlink: disallow subscribing to unknown
mcast groups") disallows userspace to subscribe to groups that don't
exist in kernel. As a result, communication between processes is
not possible unless they explicitly register a dummy group with the
kernel even if the communication is between userspace processes
only. NETLINK_USERSOCK cannot be used here since userspace processes
would require CAP_NET_ADMIN to receive multicast messages which
is available for priveleged processes only.

Fix this problem by reverting the change till a solution is
determined internally and upstream discussion.

CRs-Fixed: 2086060
Change-Id: Id559d9ef9d1e0a25e3bbdc81503978f01c6ed85f
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>

parent 22ea3159

net/netlink/genetlink.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -963,7 +963,7 @@ static struct genl_family genl_ctrl __ro_after_init = {
		static int genl_bind(struct net *net, int group)
		{
		struct genl_family *f;
		int err = -ENOENT;
		int err = 0;
		unsigned int id;

		down_read(&cb_lock);