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From:   Eyal Birger <eyal.birger@gmail.com>
To:     dsahern@kernel.org, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, yoshfuji@linux-ipv6.org,
        steffen.klassert@secunet.com
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        nicolas.dichtel@6wind.com, shmulik.ladkani@gmail.com,
        Eyal Birger <eyal.birger@gmail.com>
Subject: [PATCH ipsec-next] xfrm: no need to set DST_NOPOLICY in IPv4
Date:   Fri, 20 May 2022 13:48:45 +0300
Message-Id: <20220520104845.2644470-1-eyal.birger@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

This is a cleanup patch following commit e6175a2ed1f1
("xfrm: fix "disable_policy" flag use when arriving from different devices")
which made DST_NOPOLICY no longer be used for inbound policy checks.

On outbound the flag was set, but never used.

As such, avoid setting it altogether and remove the nopolicy argument
from rt_dst_alloc().

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>

---

This patch assumes ipsec-next is aligned with net-next and commit
e6175a2ed1f1 is already merged.
---
 drivers/net/vrf.c   |  2 +-
 include/net/route.h |  3 +--
 net/ipv4/route.c    | 24 ++++++++----------------
 3 files changed, 10 insertions(+), 19 deletions(-)

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index cfc30ce4c6e1..3c99de582c09 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -1077,7 +1077,7 @@ static int vrf_rtable_create(struct net_device *dev)
 		return -ENOMEM;
 
 	/* create a dst for routing packets out through a VRF device */
-	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1);
+	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1);
 	if (!rth)
 		return -ENOMEM;
 
diff --git a/include/net/route.h b/include/net/route.h
index 991a3985712d..b6743ff88e30 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -244,8 +244,7 @@ void ip_rt_multicast_event(struct in_device *);
 int ip_rt_ioctl(struct net *, unsigned int cmd, struct rtentry *rt);
 void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt);
 struct rtable *rt_dst_alloc(struct net_device *dev,
-			     unsigned int flags, u16 type,
-			     bool nopolicy, bool noxfrm);
+			    unsigned int flags, u16 type, bool noxfrm);
 struct rtable *rt_dst_clone(struct net_device *dev, struct rtable *rt);
 
 struct in_ifaddr;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 356f535f3443..d990bb3b1587 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1627,12 +1627,11 @@ static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
 
 struct rtable *rt_dst_alloc(struct net_device *dev,
 			    unsigned int flags, u16 type,
-			    bool nopolicy, bool noxfrm)
+			    bool noxfrm)
 {
 	struct rtable *rt;
 
 	rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
-		       (nopolicy ? DST_NOPOLICY : 0) |
 		       (noxfrm ? DST_NOXFRM : 0));
 
 	if (rt) {
@@ -1727,7 +1726,6 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	struct in_device *in_dev = __in_dev_get_rcu(dev);
 	unsigned int flags = RTCF_MULTICAST;
 	struct rtable *rth;
-	bool no_policy;
 	u32 itag = 0;
 	int err;
 
@@ -1738,12 +1736,11 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	if (our)
 		flags |= RTCF_LOCAL;
 
-	no_policy = IN_DEV_ORCONF(in_dev, NOPOLICY);
-	if (no_policy)
+	if (IN_DEV_ORCONF(in_dev, NOPOLICY))
 		IPCB(skb)->flags |= IPSKB_NOPOLICY;
 
 	rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST,
-			   no_policy, false);
+			   false);
 	if (!rth)
 		return -ENOBUFS;
 
@@ -1802,7 +1799,7 @@ static int __mkroute_input(struct sk_buff *skb,
 	struct rtable *rth;
 	int err;
 	struct in_device *out_dev;
-	bool do_cache, no_policy;
+	bool do_cache;
 	u32 itag = 0;
 
 	/* get a working reference to the output device */
@@ -1847,8 +1844,7 @@ static int __mkroute_input(struct sk_buff *skb,
 		}
 	}
 
-	no_policy = IN_DEV_ORCONF(in_dev, NOPOLICY);
-	if (no_policy)
+	if (IN_DEV_ORCONF(in_dev, NOPOLICY))
 		IPCB(skb)->flags |= IPSKB_NOPOLICY;
 
 	fnhe = find_exception(nhc, daddr);
@@ -1863,7 +1859,7 @@ static int __mkroute_input(struct sk_buff *skb,
 		}
 	}
 
-	rth = rt_dst_alloc(out_dev->dev, 0, res->type, no_policy,
+	rth = rt_dst_alloc(out_dev->dev, 0, res->type,
 			   IN_DEV_ORCONF(out_dev, NOXFRM));
 	if (!rth) {
 		err = -ENOBUFS;
@@ -2238,7 +2234,6 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	struct rtable	*rth;
 	struct flowi4	fl4;
 	bool do_cache = true;
-	bool no_policy;
 
 	/* IP on this device is disabled. */
 
@@ -2357,8 +2352,7 @@ out:	return err;
 	RT_CACHE_STAT_INC(in_brd);
 
 local_input:
-	no_policy = IN_DEV_ORCONF(in_dev, NOPOLICY);
-	if (no_policy)
+	if (IN_DEV_ORCONF(in_dev, NOPOLICY))
 		IPCB(skb)->flags |= IPSKB_NOPOLICY;
 
 	do_cache &= res->fi && !itag;
@@ -2374,8 +2368,7 @@ out:	return err;
 	}
 
 	rth = rt_dst_alloc(ip_rt_get_dev(net, res),
-			   flags | RTCF_LOCAL, res->type,
-			   no_policy, false);
+			   flags | RTCF_LOCAL, res->type, false);
 	if (!rth)
 		goto e_nobufs;
 
@@ -2598,7 +2591,6 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 
 add:
 	rth = rt_dst_alloc(dev_out, flags, type,
-			   IN_DEV_ORCONF(in_dev, NOPOLICY),
 			   IN_DEV_ORCONF(in_dev, NOXFRM));
 	if (!rth)
 		return ERR_PTR(-ENOBUFS);
-- 
2.34.1