[Devel] [PATCH] Fix again the fl6_sock_lookup() fixed locking

[Pavel Emelyanov]

YOSHIFUJI fairly pointed out, that the users increment should
be done under the ip6_sk_fl_lock not to give IPV6_FL_A_PUT a
chance to put this count to zero and release the flowlabel.

Signed-off-by: Pavel Emelyanov <xemul at openvz.org>
Cc: YOSHIFUJI Hideaki <yoshfuji at linux-ipv6.org>

---

diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index e55ae1a..b12cc22 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -210,9 +210,9 @@ struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
 	for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
 		struct ip6_flowlabel *fl = sfl->fl;
 		if (fl->label == label) {
-			read_unlock_bh(&ip6_sk_fl_lock);
 			fl->lastuse = jiffies;
 			atomic_inc(&fl->users);
+			read_unlock_bh(&ip6_sk_fl_lock);
 			return fl;
 		}
 	}