Tariq repored local pings to linklocal address is failing:
$ ifconfig ens8
ens8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 11.141.16.6 netmask 255.255.0.0 broadcast 11.141.255.255
inet6 fe80::7efe:90ff:fecb:7502 prefixlen 64 scopeid 0x20<link>
ether 7c:fe:90:cb:75:02 txqueuelen 1000 (Ethernet)
RX packets 12 bytes 1164 (1.1 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 30 bytes 2484 (2.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
$ /bin/ping6 -c 3 fe80::7efe:90ff:fecb:7502%ens8
PING fe80::7efe:90ff:fecb:7502%ens8(fe80::7efe:90ff:fecb:7502) 56 data bytes
--- fe80::7efe:90ff:fecb:7502%ens8 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2043ms
icmpv6_echo_reply needs to use the rt6i_idev dev index for local traffic
similar to how icmp6_send does. Convert the change for icmp6_send into a
helper that can be used in both places. Add the long over due
skb_rt6_info helper to convert dst on an skb to rt6_info similar to
skb_rtable for ipv4.
Fixes: 4832c30d5458 ("net: ipv6: put host and anycast routes on
device with address")
Reported-by: Tariq Toukan <tar...@mellanox.com>
Signed-off-by: David Ahern <dsah...@gmail.com>
---
include/net/ip6_route.h | 10 ++++++++++
net/ipv6/icmp.c | 33 ++++++++++++++++++++-------------
2 files changed, 30 insertions(+), 13 deletions(-)
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 882bc3c7ccde..ee96f402cb75 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -164,6 +164,16 @@ void rt6_mtu_change(struct net_device *dev, unsigned int
mtu);
void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
+static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb)
+{
+ const struct dst_entry *dst = skb_dst(skb);
+ const struct rt6_info *rt6 = NULL;
+
+ if (dst)
+ rt6 = container_of(dst, struct rt6_info, dst);
+
+ return rt6;
+}
/*
* Store a destination cache entry in a socket
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index dd7608cf1d72..c25b5954cfbb 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -399,6 +399,24 @@ static struct dst_entry *icmpv6_route_lookup(struct net
*net,
return ERR_PTR(err);
}
+static int icmp6_iif(const struct sk_buff *skb)
+{
+ int iif = skb->dev->ifindex;
+
+ /* for local traffic to local address, skb dev is the loopback
+ * device. Check if there is a dst attached to the skb and if so
+ * get the real device index.
+ */
+ if (unlikely(iif == LOOPBACK_IFINDEX)) {
+ const struct rt6_info *rt6 = skb_rt6_info(skb);
+
+ if (rt6)
+ iif = rt6->rt6i_idev->dev->ifindex;
+ }
+
+ return iif;
+}
+
/*
* Send an ICMP message in response to a packet in error
*/
@@ -460,18 +478,7 @@ static void icmp6_send(struct sk_buff *skb, u8 type, u8
code, __u32 info,
*/
if (__ipv6_addr_needs_scope_id(addr_type)) {
- iif = skb->dev->ifindex;
-
- /* for local packets, get the real device index */
- if (iif == LOOPBACK_IFINDEX) {
- dst = skb_dst(skb);
- if (dst) {
- struct rt6_info *rt;
-
- rt = container_of(dst, struct rt6_info, dst);
- iif = rt->rt6i_idev->dev->ifindex;
- }
- }
+ iif = icmp6_iif(skb);
} else {
dst = skb_dst(skb);
iif = l3mdev_master_ifindex(dst ? dst->dev : skb->dev);
@@ -694,7 +701,7 @@ static void icmpv6_echo_reply(struct sk_buff *skb)
fl6.daddr = ipv6_hdr(skb)->saddr;
if (saddr)
fl6.saddr = *saddr;
- fl6.flowi6_oif = skb->dev->ifindex;
+ fl6.flowi6_oif = icmp6_iif(skb);
fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
fl6.flowi6_mark = mark;
fl6.flowi6_uid = sock_net_uid(net, NULL);
--
2.1.4
