Commit 02a07046 authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by David S. Miller
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arcnet: provide a buffer big enough to actually receive packets 



struct archdr is only big enough to hold the header of various types of
arcnet packets. So to provide enough space to hold the data read from
hardware provide a buffer large enough to hold a packet with maximal
size.

The problem was noticed by the stack protector which makes the kernel
oops.

Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: default avatarMichael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0edc3f70

drivers/net/arcnet/arcnet.c

+17 −14
Original line number Diff line number Diff line
@@ -1063,31 +1063,34 @@ EXPORT_SYMBOL(arcnet_interrupt); 
static void arcnet_rx(struct net_device *dev, int bufnum)

{

	struct arcnet_local *lp = netdev_priv(dev);

	union {

		struct archdr pkt;

		char buf[512];

	} rxdata;

	struct arc_rfc1201 *soft;

	int length, ofs;



	soft = &pkt.soft.rfc1201;

	soft = &rxdata.pkt.soft.rfc1201;



	lp->hw.copy_from_card(dev, bufnum, 0, &pkt, ARC_HDR_SIZE);

	if (pkt.hard.offset[0]) {

		ofs = pkt.hard.offset[0];

	lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);

	if (rxdata.pkt.hard.offset[0]) {

		ofs = rxdata.pkt.hard.offset[0];

		length = 256 - ofs;

	} else {

		ofs = pkt.hard.offset[1];

		ofs = rxdata.pkt.hard.offset[1];

		length = 512 - ofs;

	}



	/* get the full header, if possible */

	if (sizeof(pkt.soft) <= length) {

		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(pkt.soft));

	if (sizeof(rxdata.pkt.soft) <= length) {

		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));

	} else {

		memset(&pkt.soft, 0, sizeof(pkt.soft));

		memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));

		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);

	}



	arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",

		   bufnum, pkt.hard.source, pkt.hard.dest, length);

		   bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);



	dev->stats.rx_packets++;

	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
@@ -1096,13 +1099,13 @@ static void arcnet_rx(struct net_device *dev, int bufnum) 
	if (arc_proto_map[soft->proto]->is_ip) {

		if (BUGLVL(D_PROTO)) {

			struct ArcProto

			*oldp = arc_proto_map[lp->default_proto[pkt.hard.source]],

			*oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],

			*newp = arc_proto_map[soft->proto];



			if (oldp != newp) {

				arc_printk(D_PROTO, dev,

					   "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",

					   soft->proto, pkt.hard.source,

					   soft->proto, rxdata.pkt.hard.source,

					   newp->suffix, oldp->suffix);

			}

		}
@@ -1111,10 +1114,10 @@ static void arcnet_rx(struct net_device *dev, int bufnum) 
		lp->default_proto[0] = soft->proto;



		/* in striking contrast, the following isn't a hack. */

		lp->default_proto[pkt.hard.source] = soft->proto;

		lp->default_proto[rxdata.pkt.hard.source] = soft->proto;

	}

	/* call the protocol-specific receiver. */

	arc_proto_map[soft->proto]->rx(dev, bufnum, &pkt, length);

	arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);

}



static void null_rx(struct net_device *dev, int bufnum,