This is a note to let you know that I've just added the patch titled route: do not cache fib route info on local routes with oif to the 3.14-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: route-do-not-cache-fib-route-info-on-local-routes-with-oif.patch and it can be found in the queue-3.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon May 16 14:28:52 PDT 2016 From: Chris Friesen <chris.friesen@xxxxxxxxxxxxx> Date: Fri, 8 Apr 2016 15:21:30 -0600 Subject: route: do not cache fib route info on local routes with oif Status: RO Content-Length: 2273 Lines: 56 From: Chris Friesen <chris.friesen@xxxxxxxxxxxxx> [ Upstream commit d6d5e999e5df67f8ec20b6be45e2229455ee3699 ] For local routes that require a particular output interface we do not want to cache the result. Caching the result causes incorrect behaviour when there are multiple source addresses on the interface. The end result being that if the intended recipient is waiting on that interface for the packet he won't receive it because it will be delivered on the loopback interface and the IP_PKTINFO ipi_ifindex will be set to the loopback interface as well. This can be tested by running a program such as "dhcp_release" which attempts to inject a packet on a particular interface so that it is received by another program on the same board. The receiving process should see an IP_PKTINFO ipi_ifndex value of the source interface (e.g., eth1) instead of the loopback interface (e.g., lo). The packet will still appear on the loopback interface in tcpdump but the important aspect is that the CMSG info is correct. Sample dhcp_release command line: dhcp_release eth1 192.168.204.222 02:11:33:22:44:66 Signed-off-by: Allain Legacy <allain.legacy@xxxxxxxxxxxxx> Signed off-by: Chris Friesen <chris.friesen@xxxxxxxxxxxxx> Reviewed-by: Julian Anastasov <ja@xxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/route.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1926,6 +1926,18 @@ static struct rtable *__mkroute_output(c */ if (fi && res->prefixlen < 4) fi = NULL; + } else if ((type == RTN_LOCAL) && (orig_oif != 0) && + (orig_oif != dev_out->ifindex)) { + /* For local routes that require a particular output interface + * we do not want to cache the result. Caching the result + * causes incorrect behaviour when there are multiple source + * addresses on the interface, the end result being that if the + * intended recipient is waiting on that interface for the + * packet he won't receive it because it will be delivered on + * the loopback interface and the IP_PKTINFO ipi_ifindex will + * be set to the loopback interface as well. + */ + fi = NULL; } fnhe = NULL; Patches currently in stable-queue which might be from chris.friesen@xxxxxxxxxxxxx are queue-3.14/route-do-not-cache-fib-route-info-on-local-routes-with-oif.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html