main/linux-grsec: add missing 0019-ipv4-check-rt_genid-in-dst_check.patch

should have been there all the way

1 files changed, 96 insertions, 0 deletions

diff --git a/main/linux-grsec/0019-ipv4-check-rt_genid-in-dst_check.patch b/main/linux-grsec/0019-ipv4-check-rt_genid-in-dst_check.patch
new file mode 100644
index 000000000..e1e9a655e
--- /dev/null
+++ b/main/linux-grsec/0019-ipv4-check-rt_genid-in-dst_check.patch
@@ -0,0 +1,96 @@
+From d11a4dc18bf41719c9f0d7ed494d295dd2973b92 Mon Sep 17 00:00:00 2001
+From: =?utf8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
+Date: Thu, 18 Mar 2010 23:20:20 +0000
+Subject: [PATCH] ipv4: check rt_genid in dst_check
+
+Xfrm_dst keeps a reference to ipv4 rtable entries on each
+cached bundle. The only way to renew xfrm_dst when the underlying
+route has changed, is to implement dst_check for this. This is
+what ipv6 side does too.
+
+The problems started after 87c1e12b5eeb7b30b4b41291bef8e0b41fc3dde9
+("ipsec: Fix bogus bundle flowi") which fixed a bug causing xfrm_dst
+to not get reused, until that all lookups always generated new
+xfrm_dst with new route reference and path mtu worked. But after the
+fix, the old routes started to get reused even after they were expired
+causing pmtu to break (well it would occationally work if the rtable
+gc had run recently and marked the route obsolete causing dst_check to
+get called).
+
+Signed-off-by: Timo Teras <timo.teras@iki.fi>
+Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ net/ipv4/route.c |   14 ++++++++++----
+ 1 files changed, 10 insertions(+), 4 deletions(-)
+
+diff --git a/net/ipv4/route.c b/net/ipv4/route.c
+index a770df2..32d3961 100644
+--- a/net/ipv4/route.c
++++ b/net/ipv4/route.c
+@@ -1441,7 +1441,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
+ 					dev_hold(rt->u.dst.dev);
+ 				if (rt->idev)
+ 					in_dev_hold(rt->idev);
+-				rt->u.dst.obsolete	= 0;
++				rt->u.dst.obsolete	= -1;
+ 				rt->u.dst.lastuse	= jiffies;
+ 				rt->u.dst.path		= &rt->u.dst;
+ 				rt->u.dst.neighbour	= NULL;
+@@ -1506,7 +1506,7 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
+ 	struct dst_entry *ret = dst;
+ 
+ 	if (rt) {
+-		if (dst->obsolete) {
++		if (dst->obsolete > 0) {
+ 			ip_rt_put(rt);
+ 			ret = NULL;
+ 		} else if ((rt->rt_flags & RTCF_REDIRECTED) ||
+@@ -1726,7 +1726,9 @@ static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
+ 
+ static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
+ {
+-	return NULL;
++	if (rt_is_expired((struct rtable *)dst))
++		return NULL;
++	return dst;
+ }
+ 
+ static void ipv4_dst_destroy(struct dst_entry *dst)
+@@ -1888,7 +1890,8 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+ 	if (!rth)
+ 		goto e_nobufs;
+ 
+-	rth->u.dst.output= ip_rt_bug;
++	rth->u.dst.output = ip_rt_bug;
++	rth->u.dst.obsolete = -1;
+ 
+ 	atomic_set(&rth->u.dst.__refcnt, 1);
+ 	rth->u.dst.flags= DST_HOST;
+@@ -2054,6 +2057,7 @@ static int __mkroute_input(struct sk_buff *skb,
+ 	rth->fl.oif 	= 0;
+ 	rth->rt_spec_dst= spec_dst;
+ 
++	rth->u.dst.obsolete = -1;
+ 	rth->u.dst.input = ip_forward;
+ 	rth->u.dst.output = ip_output;
+ 	rth->rt_genid = rt_genid(dev_net(rth->u.dst.dev));
+@@ -2218,6 +2222,7 @@ local_input:
+ 		goto e_nobufs;
+ 
+ 	rth->u.dst.output= ip_rt_bug;
++	rth->u.dst.obsolete = -1;
+ 	rth->rt_genid = rt_genid(net);
+ 
+ 	atomic_set(&rth->u.dst.__refcnt, 1);
+@@ -2444,6 +2449,7 @@ static int __mkroute_output(struct rtable **result,
+ 	rth->rt_spec_dst= fl->fl4_src;
+ 
+ 	rth->u.dst.output=ip_output;
++	rth->u.dst.obsolete = -1;
+ 	rth->rt_genid = rt_genid(dev_net(dev_out));
+ 
+ 	RT_CACHE_STAT_INC(out_slow_tot);
+-- 
+1.7.1
+