Commit cacb6ba0 authored Nov 03, 2012 by Cyrill Gorcunov Committed by David S. Miller Nov 04, 2012

net: inet_diag -- Return error code if protocol handler is missed



We've observed that in case if UDP diag module is not
supported in kernel the netlink returns NLMSG_DONE without
notifying a caller that handler is missed.

This patch makes __inet_diag_dump to return error code instead.

So as example it become possible to detect such situation
and handle it gracefully on userspace level.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: David Miller <davem@davemloft.net>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent efc7ce03

net/ipv4/inet_diag.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -892,13 +892,16 @@ static int __inet_diag_dump(struct sk_buff skb, struct netlink_callback cb,
		struct inet_diag_req_v2 r, struct nlattr bc)
		{
		const struct inet_diag_handler *handler;
		int err = 0;

		handler = inet_diag_lock_handler(r->sdiag_protocol);
		if (!IS_ERR(handler))
		handler->dump(skb, cb, r, bc);
		else
		err = PTR_ERR(handler);
		inet_diag_unlock_handler(handler);

		return skb->len;
		return err ? : skb->len;
		}

		static int inet_diag_dump(struct sk_buff skb, struct netlink_callback cb)