zero length frame filtering in AX25

PATCH Applied bernard pidoux 1 participant 1 message Mar 19, 2009 Networking

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bernard pidoux

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2009-03-19 18:16 UTC #0 lore raw

PATCH 2/3 zero length frame filtering in AX25

In previous commit 244f46ae6e9e18f6fc0be7d1f49febde4762c34b was introduced a zero length frame filter for ROSE protocole. This patch has the same purpose at AX25 frame level for the same reason. Empty frames have no meaning in AX25 protocole.

Signed-off-by Bernard Pidoux <[email protected]>

---
 net/ax25/af_ax25.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

net/ax25/af_ax25.c +12 -0

index 532a031..ca32f57 100644
@@ -1435,6 +1435,11 @@ static int ax25_sendmsg(struct kiocb *iocb, struct socket *sock,
 	size_t size;
 	int lv, err, addr_len = msg->msg_namelen;
 
+	/* AX.25 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;

@@ -1634,6 +1639,13 @@ static int ax25_recvmsg(struct kiocb *iocb, struct socket *sock,
 	skb_reset_transport_header(skb);
 	copied = skb->len;
 
+	/* AX.25 empty data frame has no meaning : ignore it */
+	if (copied == 0) {
+		err = copied;
+		skb_free_datagram(sk, skb);
+		goto out;
+	}
+
 	if (copied > size) {
 		copied = size;
 		msg->msg_flags |= MSG_TRUNC;

Signature · 1 line

1.6.0.6