From: David S. Miller <davem@sunset.davemloft.net>
Date: Wed, 7 Mar 2007 01:02:35 +0000 (-0800)
Subject: [NETLINK]: Mirror UDP MSG_TRUNC semantics.
X-Git-Tag: v2.6.22-rc1~1128^2~411
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b558ff799977a4eda8b3823d1cf6c1c33becb671;p=linux-2.6

[NETLINK]: Mirror UDP MSG_TRUNC semantics.

If the user passes MSG_TRUNC in via msg_flags, return
the full packet size not the truncated size.

Idea from Herbert Xu and Thomas Graf.

Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index c48b0f49f0..5890210d77 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1242,6 +1242,9 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
 
 	scm_recv(sock, msg, siocb->scm, flags);
 
+	if (flags & MSG_TRUNC)
+		copied = skb->len;
+
 out:
 	netlink_rcv_wake(sk);
 	return err ? : copied;