Bloat » Cerowrt

---------- Forwarded message ----------
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, Mar 27, 2012 at 12:53 PM
Subject: [PATCH] net: fix a potential rcu_read_lock() imbalance in
rt6_fill_node()
To: Ben Greear <greearb@candelatech.com>
Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org,
gregkh@linuxfoundation.org, "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Dave Jones <davej@redhat.com>

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 <greearb@candelatech.com>
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
---
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 24c456e..496b627 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)