Commit 59f21118 authored Jun 16, 2015 by Willem de Bruijn Committed by David S. Miller Jun 21, 2015

packet: free packet_rollover after synchronize_net



Destruction of the po->rollover must be delayed until there are no
more packets in flight that can access it. The field is destroyed in
packet_release, before synchronize_net. Delay using rcu.

Fixes: 0648ab70 ("packet: rollover prepare: per-socket state")

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 12011962

net/packet/af_packet.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -1634,7 +1634,8 @@ static void fanout_release(struct sock *sk)
		}
		mutex_unlock(&fanout_mutex);

		kfree(po->rollover);
		if (po->rollover)
		kfree_rcu(po->rollover, rcu);
		}

		static const struct proto_ops packet_ops;

net/packet/internal.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -89,6 +89,7 @@ struct packet_fanout {

		struct packet_rollover {
		int sock;
		struct rcu_head rcu;
		atomic_long_t num;
		atomic_long_t num_huge;
		atomic_long_t num_failed;

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