From 7dd73168e273938b9e9bb42ca51b0c27d807992b Mon Sep 17 00:00:00 2001 From: David Ahern Date: Mon, 3 Jun 2019 18:37:03 -0700 Subject: [PATCH] ipv6: Always allocate pcpu memory in a fib6_nh A recent commit had an unintended side effect with reject routes: rt6i_pcpu is expected to always be initialized for all fib6_info except the null entry. The commit mentioned below skips it for reject routes and ends up leaking references to the loopback device. For example, ip netns add foo ip -netns foo li set lo up ip -netns foo -6 ro add blackhole 2001:db8:1::1 ip netns exec foo ping6 2001:db8:1::1 ip netns del foo ends up spewing: unregister_netdevice: waiting for lo to become free. Usage count = 3 The fib_nh_common_init is not needed for reject routes (no ipv4 caching or encaps), so move the alloc_percpu_gfp after it and adjust the goto label. Fixes: f40b6ae2b612 ("ipv6: Move pcpu cached routes to fib6_nh") Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/route.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index a72d01010cb6..9b9a0159f7fd 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3113,7 +3113,7 @@ int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh, goto out; } } - goto set_dev; + goto pcpu_alloc; } if (cfg->fc_flags & RTF_GATEWAY) { @@ -3145,17 +3145,18 @@ int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh, !netif_carrier_ok(dev)) fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN; + err = fib_nh_common_init(&fib6_nh->nh_common, cfg->fc_encap, + cfg->fc_encap_type, cfg, gfp_flags, extack); + if (err) + goto out; + +pcpu_alloc: fib6_nh->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags); if (!fib6_nh->rt6i_pcpu) { err = -ENOMEM; goto out; } - err = fib_nh_common_init(&fib6_nh->nh_common, cfg->fc_encap, - cfg->fc_encap_type, cfg, gfp_flags, extack); - if (err) - goto out; -set_dev: fib6_nh->fib_nh_dev = dev; fib6_nh->fib_nh_oif = dev->ifindex; err = 0; -- GitLab