From 94f826b8076e2cb92242061e92f21b5baa3eccc2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 27 Mar 2012 09:53:52 +0000 Subject: [PATCH] net: fix a potential rcu_read_lock() imbalance in rt6_fill_node() Commit f2c31e32b378 (net: fix NULL dereferences in check_peer_redir() ) added a regression in rt6_fill_node(), leading to rcu_read_lock() imbalance. Thats because NLA_PUT() can make a jump to nla_put_failure label. Fix this by using nla_put() Many thanks to Ben Greear for his help Reported-by: Ben Greear Reported-by: Dave Jones Signed-off-by: Eric Dumazet Tested-by: Ben Greear Signed-off-by: David S. Miller --- net/ipv6/route.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 24c456e8aa1d..496b62712fe8 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2474,8 +2474,12 @@ static int rt6_fill_node(struct net *net, rcu_read_lock(); n = dst_get_neighbour_noref(&rt->dst); - if (n) - NLA_PUT(skb, RTA_GATEWAY, 16, &n->primary_key); + if (n) { + if (nla_put(skb, RTA_GATEWAY, 16, &n->primary_key) < 0) { + rcu_read_unlock(); + goto nla_put_failure; + } + } rcu_read_unlock(); if (rt->dst.dev) -- 2.20.1