route: also update fnhe_genid when updating a route cache

[ Upstream commit cebe84c619 ]

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: 5aad1de5ea ("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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Xin Long 2017-11-17 14:27:18 +08:00 committed by Greg Kroah-Hartman
parent ffe6293d19
commit 407de7d97a

View file

@ -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) {
@ -700,7 +705,7 @@ 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;