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Patch "ip: report the original address of ICMP messages" has been added to the 4.1-stable tree

PATCH [email protected] 1 participant 1 message Jul 4, 2015

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This is a note to let you know that I've just added the patch titled

ip: report the original address of ICMP messages

to the 4.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ip-report-the-original-address-of-icmp-messages.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From foo@baz Fri Jul 3 20:00:25 PDT 2015

From: Julian Anastasov <[email protected]>
Date: Tue, 23 Jun 2015 08:34:39 +0300
Subject: ip: report the original address of ICMP messages

From: Julian Anastasov <[email protected]>

[ Upstream commit 34b99df4e6256ddafb663c6de0711dceceddfe0e ]

ICMP messages can trigger ICMP and local errors. In this case serr->port is 0 and starting from Linux 4.0 we do not return the original target address to the error queue readers. Add function to define which errors provide addr_offset. With this fix my ping command is not silent anymore.

Fixes c247f0534cc5 ("ip: fix error queue empty skb handling")
Signed-off-by Julian Anastasov <[email protected]>
Acked-by Willem de Bruijn <[email protected]>
Signed-off-by David S. Miller <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>
---
 net/ipv4/ip_sockglue.c |   11 ++++++++++-
 net/ipv6/datagram.c    |   12 +++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)
net/ipv4/ip_sockglue.c +10 -1
@@ -432,6 +432,15 @@ void ip_local_error(struct sock *sk, int
 		kfree_skb(skb);
 }
 
+/* For some errors we have valid addr_offset even with zero payload and
+ * zero port. Also, addr_offset should be supported if port is set.
+ */
+static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr)
+{
+	return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
+	       serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
+}
+
 /* IPv4 supports cmsg on all imcp errors and some timestamps
  *
  * Timestamp code paths do not initialize the fields expected by cmsg:

@@ -498,7 +507,7 @@ int ip_recv_error(struct sock *sk, struc
 
 	serr = SKB_EXT_ERR(skb);
 
-	if (sin && serr->port) {
+	if (sin && ipv4_datagram_support_addr(serr)) {
 		sin->sin_family = AF_INET;
 		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
 						   serr->addr_offset);
net/ipv6/datagram.c +11 -1
@@ -325,6 +325,16 @@ void ipv6_local_rxpmtu(struct sock *sk,
 	kfree_skb(skb);
 }
 
+/* For some errors we have valid addr_offset even with zero payload and
+ * zero port. Also, addr_offset should be supported if port is set.
+ */
+static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
+{
+	return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
+	       serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
+	       serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
+}
+
 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
  *
  * At one point, excluding local errors was a quick test to identify icmp/icmp6

@@ -389,7 +399,7 @@ int ipv6_recv_error(struct sock *sk, str
 
 	serr = SKB_EXT_ERR(skb);
 
-	if (sin && serr->port) {
+	if (sin && ipv6_datagram_support_addr(serr)) {
 		const unsigned char *nh = skb_network_header(skb);
 		sin->sin6_family = AF_INET6;
 		sin->sin6_flowinfo = 0;

Patches currently in stable-queue which might be from [email protected] are

queue-4.1/neigh-do-not-modify-unlinked-entries.patch queue-4.1/ip-report-the-original-address-of-icmp-messages.patch