[PATCH 3/3] [NETROM] zero length frame filtering in NetRom

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
From: bernard pidoux
Date: Thursday, March 19, 2009 - 11:18 am

A zero length frame filter was recently introduced in ROSE protocole.
Previous commit makes the same at AX25 protocole level.
This patch has the same purpose for NetRom  protocole.
The reason is that empty frames have no meaning in NetRom protocole.

Signed-off-by: Bernard Pidoux <f6bvp@amsat.org>
---
 net/netrom/af_netrom.c |   11 ++++++++++-
 1 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
index e9c05b8..ec6c898 100644
--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -1037,6 +1037,10 @@ static int nr_sendmsg(struct kiocb *iocb, struct socket *sock,
 	unsigned char *asmptr;
 	int size;
 
+	/* Netrom empty data frame has no meaning : don't send */
+	if (len == 0)
+		return 0;
+
 	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
 		return -EINVAL;
 
@@ -1167,6 +1171,11 @@ static int nr_recvmsg(struct kiocb *iocb, struct socket *sock,
 	skb_reset_transport_header(skb);
 	copied     = skb->len;
 
+	/* NetRom empty data frame has no meaning : ignore it */
+	if (copied == 0) {
+		goto out;
+	}
+
 	if (copied > size) {
 		copied = size;
 		msg->msg_flags |= MSG_TRUNC;
@@ -1182,7 +1191,7 @@ static int nr_recvmsg(struct kiocb *iocb, struct socket *sock,
 
 	msg->msg_namelen = sizeof(*sax);
 
-	skb_free_datagram(sk, skb);
+out:	skb_free_datagram(sk, skb);
 
 	release_sock(sk);
 	return copied;
-- 
1.6.0.6

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[PATCH 3/3] [NETROM] zero length frame filtering in NetRom, bernard pidoux, (Thu Mar 19, 11:18 am)
swapper Not tainted 2.6.29.6, Bernard Pidoux F6BVP, (Tue Aug 11, 3:23 am)