Subject: [PATCH 06/12] net/ipv6: Correct PIM6 mrt_lock handling

From: Richard Laing <[email-masked]>
Date: Thu, 3 Sep 2015 13:52:31 +1200

[ Upstream commit 25b4a44c19c83d98e8c0807a7ede07c1f28eab8b ]

In the IPv6 multicast routing code the mrt_lock was not being released
correctly in the MFC iterator, as a result adding or deleting a MIF would
cause a hang because the mrt_lock could not be acquired.

This fix is a copy of the code for the IPv4 case and ensures that the lock
is released correctly.

Signed-off-by: Richard Laing <[email-masked]>
Acked-by: Cong Wang <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 net/ipv6/ip6mr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 1a01d79..0d58542 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -552,7 +552,7 @@ static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
 
 	if (it->cache == &mrt->mfc6_unres_queue)
 		spin_unlock_bh(&mfc_unres_lock);
-	else if (it->cache == mrt->mfc6_cache_array)
+	else if (it->cache == &mrt->mfc6_cache_array[it->ct])
 		read_unlock(&mrt_lock);
 }
 
-- 
2.1.0