Commit 6885ffb3 authored by Mark Smith's avatar Mark Smith Committed by David S. Miller
Browse files

Use correct NET_RX_* returns for atalk_rcv() 



In all rx'd SKB cases, atalk_rcv() either eventually jumps to or falls through
    to the label out:, which  returns numeric 0. Numeric 0 corresponds to
    NET_RX_SUCCESS, which is incorrect in failed SKB cases.

    This patch makes atalk_rcv() provide the correct returns by:

    o  explicitly returning NET_RX_SUCCESS in the two success cases
    o  having the out: label return NET_RX_DROP, instead of numeric 0
    o  making the failed SKB labels and processing more consistent with other
       _rcv() routines in the kernel, simplifying validation and removing a
       backwards goto

Signed-off-by: default avatarMark Smith <markzzzsmith@yahoo.com.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent b91cd144

net/appletalk/ddp.c

+14 −11
Original line number Diff line number Diff line
@@ -1400,7 +1400,7 @@ static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 
	__u16 len_hops;



	if (!net_eq(dev_net(dev), &init_net))

		goto freeit;

		goto drop;



	/* Don't mangle buffer if shared */

	if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
@@ -1408,7 +1408,7 @@ static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 


	/* Size check and make sure header is contiguous */

	if (!pskb_may_pull(skb, sizeof(*ddp)))

		goto freeit;

		goto drop;



	ddp = ddp_hdr(skb);
@@ -1426,7 +1426,7 @@ static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 
	if (skb->len < sizeof(*ddp) || skb->len < (len_hops & 1023)) {

		pr_debug("AppleTalk: dropping corrupted frame (deh_len=%u, "

			 "skb->len=%u)\n", len_hops & 1023, skb->len);

		goto freeit;

		goto drop;

	}



	/*
@@ -1436,7 +1436,7 @@ static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 
	if (ddp->deh_sum &&

	    atalk_checksum(skb, len_hops & 1023) != ddp->deh_sum)

		/* Not a valid AppleTalk frame - dustbin time */

		goto freeit;

		goto drop;



	/* Check the packet is aimed at us */

	if (!ddp->deh_dnet)	/* Net 0 is 'this network' */
@@ -1449,7 +1449,7 @@ static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 
		 * AppleTalk iface

		 */

		atalk_route_packet(skb, dev, ddp, len_hops, origlen);

		goto out;

		return NET_RX_SUCCESS;

	}



	/* if IP over DDP is not selected this code will be optimized out */
@@ -1465,18 +1465,21 @@ static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 


	sock = atalk_search_socket(&tosat, atif);

	if (!sock) /* But not one of our sockets */

		goto freeit;

		goto drop;



	/* Queue packet (standard) */

	skb->sk = sock;



	if (sock_queue_rcv_skb(sock, skb) < 0)

		goto freeit;

out:

	return 0;

freeit:

		goto drop;



	return NET_RX_SUCCESS;



drop:

	kfree_skb(skb);

	goto out;

out:

	return NET_RX_DROP;



}



/*

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