96 lines
3.1 KiB
Diff
96 lines
3.1 KiB
Diff
From e16e888b525503be05b3aea64190e8b3bdef44d0 Mon Sep 17 00:00:00 2001
|
|
From: Markus Stenberg <markus.stenberg@iki.fi>
|
|
Date: Tue, 5 May 2015 13:36:59 +0300
|
|
Subject: [PATCH] ipv6: Fixed source specific default route handling.
|
|
|
|
If there are only IPv6 source specific default routes present, the
|
|
host gets -ENETUNREACH on e.g. connect() because ip6_dst_lookup_tail
|
|
calls ip6_route_output first, and given source address any, it fails,
|
|
and ip6_route_get_saddr is never called.
|
|
|
|
The change is to use the ip6_route_get_saddr, even if the initial
|
|
ip6_route_output fails, and then doing ip6_route_output _again_ after
|
|
we have appropriate source address available.
|
|
|
|
Note that this is '99% fix' to the problem; a correct fix would be to
|
|
do route lookups only within addrconf.c when picking a source address,
|
|
and never call ip6_route_output before source address has been
|
|
populated.
|
|
|
|
Signed-off-by: Markus Stenberg <markus.stenberg@iki.fi>
|
|
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
---
|
|
net/ipv6/ip6_output.c | 39 +++++++++++++++++++++++++++++++--------
|
|
net/ipv6/route.c | 5 +++--
|
|
2 files changed, 34 insertions(+), 10 deletions(-)
|
|
|
|
--- a/net/ipv6/ip6_output.c
|
|
+++ b/net/ipv6/ip6_output.c
|
|
@@ -900,21 +900,45 @@ static int ip6_dst_lookup_tail(struct so
|
|
#endif
|
|
int err;
|
|
|
|
- if (*dst == NULL)
|
|
- *dst = ip6_route_output(net, sk, fl6);
|
|
-
|
|
- if ((err = (*dst)->error))
|
|
- goto out_err_release;
|
|
+ /* The correct way to handle this would be to do
|
|
+ * ip6_route_get_saddr, and then ip6_route_output; however,
|
|
+ * the route-specific preferred source forces the
|
|
+ * ip6_route_output call _before_ ip6_route_get_saddr.
|
|
+ *
|
|
+ * In source specific routing (no src=any default route),
|
|
+ * ip6_route_output will fail given src=any saddr, though, so
|
|
+ * that's why we try it again later.
|
|
+ */
|
|
+ if (ipv6_addr_any(&fl6->saddr) && (!*dst || !(*dst)->error)) {
|
|
+ struct rt6_info *rt;
|
|
+ bool had_dst = *dst != NULL;
|
|
|
|
- if (ipv6_addr_any(&fl6->saddr)) {
|
|
- struct rt6_info *rt = (struct rt6_info *) *dst;
|
|
+ if (!had_dst)
|
|
+ *dst = ip6_route_output(net, sk, fl6);
|
|
+ rt = (*dst)->error ? NULL : (struct rt6_info *)*dst;
|
|
err = ip6_route_get_saddr(net, rt, &fl6->daddr,
|
|
sk ? inet6_sk(sk)->srcprefs : 0,
|
|
&fl6->saddr);
|
|
if (err)
|
|
goto out_err_release;
|
|
+
|
|
+ /* If we had an erroneous initial result, pretend it
|
|
+ * never existed and let the SA-enabled version take
|
|
+ * over.
|
|
+ */
|
|
+ if (!had_dst && (*dst)->error) {
|
|
+ dst_release(*dst);
|
|
+ *dst = NULL;
|
|
+ }
|
|
}
|
|
|
|
+ if (!*dst)
|
|
+ *dst = ip6_route_output(net, sk, fl6);
|
|
+
|
|
+ err = (*dst)->error;
|
|
+ if (err)
|
|
+ goto out_err_release;
|
|
+
|
|
#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
|
|
/*
|
|
* Here if the dst entry we've looked up
|
|
--- a/net/ipv6/route.c
|
|
+++ b/net/ipv6/route.c
|
|
@@ -2182,9 +2182,10 @@ int ip6_route_get_saddr(struct net *net,
|
|
unsigned int prefs,
|
|
struct in6_addr *saddr)
|
|
{
|
|
- struct inet6_dev *idev = ip6_dst_idev((struct dst_entry *)rt);
|
|
+ struct inet6_dev *idev =
|
|
+ rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
|
|
int err = 0;
|
|
- if (rt->rt6i_prefsrc.plen)
|
|
+ if (rt && rt->rt6i_prefsrc.plen)
|
|
*saddr = rt->rt6i_prefsrc.addr;
|
|
else
|
|
err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
|