From 59f211181b5b10d4a95e1b9226febb0c0b6497c6 Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Tue, 16 Jun 2015 12:51:37 -0400 Subject: [PATCH] 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: 0648ab70afe6 ("packet: rollover prepare: per-socket state") Suggested-by: Eric Dumazet Signed-off-by: Willem de Bruijn Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/packet/af_packet.c | 3 ++- net/packet/internal.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index fd5164139bf0..20e8c40da90d 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -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; diff --git a/net/packet/internal.h b/net/packet/internal.h index c035d263c1e8..e20b3e8829b8 100644 --- a/net/packet/internal.h +++ b/net/packet/internal.h @@ -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; -- 2.30.2