From efa95b01da18ad22af62f6d99a3243f3be8fd264 Mon Sep 17 00:00:00 2001 From: david decotigny <decot@googlers.com> Date: Tue, 8 Jul 2014 15:14:41 -0700 Subject: [PATCH] netpoll: fix use after free After a bonding master reclaims the netpoll info struct, slaves could still hold a pointer to the reclaimed data. This patch fixes it: as soon as netpoll_async_cleanup is called for a slave (eg. when un-enslaved), we make sure that this slave doesn't point to the data. Signed-off-by: David Decotigny <decot@googlers.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/netpoll.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/core/netpoll.c b/net/core/netpoll.c index e33937fb32a0c..907fb5e36c02e 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -822,7 +822,8 @@ void __netpoll_cleanup(struct netpoll *np) RCU_INIT_POINTER(np->dev->npinfo, NULL); call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info); - } + } else + RCU_INIT_POINTER(np->dev->npinfo, NULL); } EXPORT_SYMBOL_GPL(__netpoll_cleanup); -- 2.30.2