Commit 4c62ab9c authored by Wolfram Sang's avatar Wolfram Sang Committed by David S. Miller
Browse files

irda: irttp: allow zero byte packets 

Sending zero byte packets is not neccessarily an error (AF_INET accepts it,
too), so just apply a shortcut. This was discovered because of a non-working
software with WINE. See

  http://bugs.winehq.org/show_bug.cgi?id=19397#c86
  http://thread.gmane.org/gmane.linux.irda.general/1643



for very detailed debugging information and a testcase. Kudos to Wolfgang for
those!

Reported-by: default avatarWolfgang Schwotzer <wolfgang.schwotzer@gmx.net>
Signed-off-by: default avatarWolfram Sang <w.sang@pengutronix.de>
Tested-by: default avatarMike Evans <mike.evans@cardolan.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3b42a96d

net/irda/irttp.c

+19 −6
Original line number Diff line number Diff line
@@ -550,16 +550,23 @@ EXPORT_SYMBOL(irttp_close_tsap); 
 */

int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb)

{

	int ret = -1;



	IRDA_ASSERT(self != NULL, return -1;);

	IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);

	IRDA_ASSERT(skb != NULL, return -1;);



	IRDA_DEBUG(4, "%s()\n", __func__);



	/* Take shortcut on zero byte packets */

	if (skb->len == 0) {

		ret = 0;

		goto err;

	}



	/* Check that nothing bad happens */

	if ((skb->len == 0) || (!self->connected)) {

		IRDA_DEBUG(1, "%s(), No data, or not connected\n",

			   __func__);

	if (!self->connected) {

		IRDA_DEBUG(1, "%s(), Not connected\n", __func__);

		goto err;

	}
@@ -576,7 +583,7 @@ int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb) 


err:

	dev_kfree_skb(skb);

	return -1;

	return ret;

}

EXPORT_SYMBOL(irttp_udata_request);
@@ -599,9 +606,15 @@ int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb) 
	IRDA_DEBUG(2, "%s() : queue len = %d\n", __func__,

		   skb_queue_len(&self->tx_queue));



	/* Take shortcut on zero byte packets */

	if (skb->len == 0) {

		ret = 0;

		goto err;

	}



	/* Check that nothing bad happens */

	if ((skb->len == 0) || (!self->connected)) {

		IRDA_WARNING("%s: No data, or not connected\n", __func__);

	if (!self->connected) {

		IRDA_WARNING("%s: Not connected\n", __func__);

		ret = -ENOTCONN;

		goto err;

	}

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