From: Eric Dumazet <[email protected]>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
[ Upstream commit 44c3d0c1c0a880354e9de5d94175742e2c7c9683 ]
Silence lockdep false positive about rcu_dereference() being
used in the wrong context.
First one should use rcu_dereference_protected() as we own the spinlock.
Second one should be a normal assignation, as no barrier is needed.
Fixes: 18367681a10bd ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.")
Reported-by: Dave Jones <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Acked-by: Hannes Frederic Sowa <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Jiri Slaby <[email protected]>
---
net/ipv6/ip6_flowlabel.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index f0ccdb787100..d14c74b2dfa3 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -527,12 +527,13 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user
*optval, int optlen)
case IPV6_FL_A_PUT:
spin_lock_bh(&ip6_sk_fl_lock);
for (sflp = &np->ipv6_fl_list;
- (sfl = rcu_dereference(*sflp))!=NULL;
+ (sfl = rcu_dereference_protected(*sflp,
+
lockdep_is_held(&ip6_sk_fl_lock))) != NULL;
sflp = &sfl->next) {
if (sfl->fl->label == freq.flr_label) {
if (freq.flr_label ==
(np->flow_label&IPV6_FLOWLABEL_MASK))
np->flow_label &= ~IPV6_FLOWLABEL_MASK;
- *sflp = rcu_dereference(sfl->next);
+ *sflp = sfl->next;
spin_unlock_bh(&ip6_sk_fl_lock);
fl_release(sfl->fl);
kfree_rcu(sfl, rcu);
--
2.7.2
