diff options
authorDmitry Butskoy <dmitry@butskoy.name>2007-07-22 18:29:30 +0200
committerAdrian Bunk <bunk@stusta.de>2007-07-22 18:29:30 +0200
commit8d2693e6821f1027e33e36284cc3cf0e8d915eb8 (patch)
parente5e0ad360edc354c661ef2ab49d42ae964fc46f7 (diff)
[IPV6]: MSG_ERRQUEUE messages do not pass to connected raw sockets
Taken from http://bugzilla.kernel.org/show_bug.cgi?id=8747 Problem Description: It is related to the possibility to obtain MSG_ERRQUEUE messages from the udp and raw sockets, both connected and unconnected. There is a little typo in net/ipv6/icmp.c code, which prevents such messages to be delivered to the errqueue of the correspond raw socket, when the socket is CONNECTED. The typo is due to swap of local/remote addresses. Consider __raw_v6_lookup() function from net/ipv6/raw.c. When a raw socket is looked up usual way, it is something like: sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr, IP6CB(skb)->iif); where "daddr" is a destination address of the incoming packet (IOW our local address), "saddr" is a source address of the incoming packet (the remote end). But when the raw socket is looked up for some icmp error report, in net/ipv6/icmp.c:icmpv6_notify() , daddr/saddr are obtained from the echoed fragment of the "bad" packet, i.e. "daddr" is the original destination address of that packet, "saddr" is our local address. Hence, for icmpv6_notify() must use "saddr, daddr" in its arguments, not "daddr, saddr" ... Steps to reproduce: Create some raw socket, connect it to an address, and cause some error situation: f.e. set ttl=1 where the remote address is more than 1 hop to reach. Set IPV6_RECVERR . Then send something and wait for the error (f.e. poll() with POLLERR|POLLIN). You should receive "time exceeded" icmp message (because of "ttl=1"), but the socket do not receive it. If you do not connect your raw socket, you will receive MSG_ERRQUEUE successfully. (The reason is that for unconnected socket there are no actual checks for local/remote addresses). Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 21eb725e885f..1992e820059f 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -574,7 +574,7 @@ static void icmpv6_notify(struct sk_buff *skb, int type, int code, u32 info)
if ((sk = sk_head(&raw_v6_htable[hash])) != NULL) {
- while((sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr,
+ while ((sk = __raw_v6_lookup(sk, nexthdr, saddr, daddr,
IP6CB(skb)->iif))) {
rawv6_err(sk, skb, NULL, type, code, inner_offset, info);
sk = sk_next(sk);