ipv4: udp: fix short packet and bad checksum logging
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@mork.no>
Cc: stable@kernel.org
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 8fef859..c36522a 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1527,6 +1527,9 @@
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 @@
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);
