[01/39] ipv4: udp: fix short packet and bad checksum logging

[Greg KH]

2.6.33-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Bjørn Mork <bjorn@xxxxxxx>

commit ccc2d97cb7c798e785c9f198de243e2b59f7073b upstream.

commit 2783ef23 moved the initialisation of saddr and daddr after
pskb_may_pull() to avoid a potential data corruption.  Unfortunately
also placing it after the short packet and bad checksum error paths,
where these variables are used for logging.  The result is bogus
output like

[92238.389505] UDP: short packet: From 2.0.0.0:65535 23715/178 to 0.0.0.0:65535

Moving the saddr and daddr initialisation above the error paths, while still
keeping it after the pskb_may_pull() to keep the fix from commit 2783ef23.

Signed-off-by: Bjørn Mork <bjorn@xxxxxxx>
Acked-by: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 net/ipv4/udp.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1527,6 +1527,9 @@ int __udp4_lib_rcv(struct sk_buff *skb,
 
 	uh   = udp_hdr(skb);
 	ulen = ntohs(uh->len);
+	saddr = ip_hdr(skb)->saddr;
+	daddr = ip_hdr(skb)->daddr;
+
 	if (ulen > skb->len)
 		goto short_packet;
 
@@ -1540,9 +1543,6 @@ int __udp4_lib_rcv(struct sk_buff *skb,
 	if (udp4_csum_init(skb, uh, proto))
 		goto csum_error;
 
-	saddr = ip_hdr(skb)->saddr;
-	daddr = ip_hdr(skb)->daddr;
-
 	if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
 		return __udp4_lib_mcast_deliver(net, skb, uh,
 				saddr, daddr, udptable);


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