route: also update fnhe_genid when updating a route cache (cebe84c6) · Commits · 戴 / test

Now when ip route flush cache and it turn out all fnhe_genid != genid. If a redirect/pmtu icmp packet comes and the old fnhe is found and all it's members but fnhe_genid will be updated. Then next time when it looks up route and tries to rebind this fnhe to the new dst, the fnhe will be flushed due to fnhe_genid != genid. It causes this redirect/pmtu icmp packet acutally not to be applied. This patch is to also reset fnhe_genid when updating a route cache. Fixes: ("ipv4: use separate genid for next hop exceptions") Acked-by:

Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by:

Xin Long <lucien.xin@gmail.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/ipv4/route.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -651,9 +651,12 @@ static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
		struct fnhe_hash_bucket *hash;
		struct fib_nh_exception *fnhe;
		struct rtable *rt;
		u32 genid, hval;
		unsigned int i;
		int depth;
		u32 hval = fnhe_hashfun(daddr);

		genid = fnhe_genid(dev_net(nh->nh_dev));
		hval = fnhe_hashfun(daddr);

		spin_lock_bh(&fnhe_lock);

		@@ -676,6 +679,8 @@ static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
		}

		if (fnhe) {
		if (fnhe->fnhe_genid != genid)
		fnhe->fnhe_genid = genid;
		if (gw)
		fnhe->fnhe_gw = gw;
		if (pmtu)
		@@ -699,7 +704,7 @@ static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
		fnhe->fnhe_next = hash->chain;
		rcu_assign_pointer(hash->chain, fnhe);
		}
		fnhe->fnhe_genid = fnhe_genid(dev_net(nh->nh_dev));
		fnhe->fnhe_genid = genid;
		fnhe->fnhe_daddr = daddr;
		fnhe->fnhe_gw = gw;
		fnhe->fnhe_pmtu = pmtu;

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