[PATCH v1 net-next 10/14] neighbour: Use rcu_dereference() in pneigh_get_{first,next}().

[Kuniyuki Iwashima <kuniyu@google.com>]

Now pneigh_entry is guaranteed to be alive during the
RCU critical section even without holding tbl->lock.

Let's use rcu_dereference() in pneigh_get_{first,next}().

Note that neigh_seq_start() still holds tbl->lock for the
normal neighbour entry.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
---
 net/core/neighbour.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index e8ca84e2ddf30..e762e88328255 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -3309,9 +3309,9 @@ static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
 
 	state->flags |= NEIGH_SEQ_IS_PNEIGH;
 	for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
-		pn = tbl->phash_buckets[bucket];
+		pn = rcu_dereference(tbl->phash_buckets[bucket]);
 		while (pn && !net_eq(pneigh_net(pn), net))
-			pn = pn->next;
+			pn = rcu_dereference(pn->next);
 		if (pn)
 			break;
 	}
@@ -3329,15 +3329,15 @@ static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
 	struct neigh_table *tbl = state->tbl;
 
 	do {
-		pn = pn->next;
+		pn = rcu_dereference(pn->next);
 	} while (pn && !net_eq(pneigh_net(pn), net));
 
 	while (!pn) {
 		if (++state->bucket > PNEIGH_HASHMASK)
 			break;
-		pn = tbl->phash_buckets[state->bucket];
+		pn = rcu_dereference(tbl->phash_buckets[state->bucket]);
 		while (pn && !net_eq(pneigh_net(pn), net))
-			pn = pn->next;
+			pn = rcu_dereference(pn->next);
 		if (pn)
 			break;
 	}
-- 
2.50.0.727.gbf7dc18ff4-goog