udp: Fix the SNMP counter of UDP_MIB_INDATAGRAMS
If UDP echo is sent to xinetd/echo-dgram, the UDP reply will be received
at the sender. But the SNMP counter of UDP_MIB_INDATAGRAMS will be not
increased, UDP6_MIB_INDATAGRAMS will be increased instead.
Endpoint A Endpoint B
UDP Echo request ----------->
(IPv4, Dst port=7)
<---------- UDP Echo Reply
(IPv4, Src port=7)
This bug is come from this patch cb75994ec311b2cd50e5205efdcc0696abd6675d.
It do counter UDP[6]_MIB_INDATAGRAMS until udp[v6]_recvmsg. Because
xinetd used IPv6 socket to receive UDP messages, thus, when received
UDP packet, the UDP6_MIB_INDATAGRAMS will be increased in function
udpv6_recvmsg() even if the packet is a IPv4 UDP packet.
This patch fixed the problem.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 71e259e..18696af 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -138,6 +138,7 @@
int peeked;
int err;
int is_udplite = IS_UDPLITE(sk);
+ int is_udp4;
if (addr_len)
*addr_len=sizeof(struct sockaddr_in6);
@@ -158,6 +159,8 @@
else if (copied < ulen)
msg->msg_flags |= MSG_TRUNC;
+ is_udp4 = (skb->protocol == htons(ETH_P_IP));
+
/*
* If checksum is needed at all, try to do it while copying the
* data. If the data is truncated, or if we only want a partial
@@ -180,9 +183,14 @@
if (err)
goto out_free;
- if (!peeked)
- UDP6_INC_STATS_USER(sock_net(sk),
- UDP_MIB_INDATAGRAMS, is_udplite);
+ if (!peeked) {
+ if (is_udp4)
+ UDP_INC_STATS_USER(sock_net(sk),
+ UDP_MIB_INDATAGRAMS, is_udplite);
+ else
+ UDP6_INC_STATS_USER(sock_net(sk),
+ UDP_MIB_INDATAGRAMS, is_udplite);
+ }
sock_recv_timestamp(msg, sk, skb);
@@ -196,7 +204,7 @@
sin6->sin6_flowinfo = 0;
sin6->sin6_scope_id = 0;
- if (skb->protocol == htons(ETH_P_IP))
+ if (is_udp4)
ipv6_addr_set(&sin6->sin6_addr, 0, 0,
htonl(0xffff), ip_hdr(skb)->saddr);
else {
@@ -207,7 +215,7 @@
}
}
- if (skb->protocol == htons(ETH_P_IP)) {
+ if (is_udp4) {
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb);
} else {