ipv6/addrlabel: fix ip6addrlbl_get()

ip6addrlbl_get() has never worked. If ip6addrlbl_hold() succeeded,
ip6addrlbl_get() will exit with '-ESRCH'. If ip6addrlbl_hold() failed,
ip6addrlbl_get() will use about to be free ip6addrlbl_entry pointer.

Fix this by inverting ip6addrlbl_hold() check.

Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Cong Wang <cwang@twopensource.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c
index 882124ebb438bd033765c4284ddf7ada9834d39d..a8f6986dcbe5ea5a36a3cc6fcf51becebb50c33b 100644 (file)
--- a/net/ipv6/addrlabel.c
+++ b/net/ipv6/addrlabel.c
@@ -552,7 +552,7 @@ static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 
        rcu_read_lock();
        p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
-       if (p && ip6addrlbl_hold(p))
+       if (p && !ip6addrlbl_hold(p))
                p = NULL;
        lseq = ip6addrlbl_table.seq;
        rcu_read_unlock();