From be33690d8fcf40377f16193c463681170eb6b295 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Mon, 20 Mar 2006 22:40:54 -0800 Subject: [XFRM]: Fix aevent related crash When xfrm_user isn't loaded xfrm_nl is NULL, which makes IPsec crash because xfrm_aevent_is_on passes the NULL pointer to netlink_has_listeners as socket. A second problem is that the xfrm_nl pointer is not cleared when the socket is releases at module unload time. Protect references of xfrm_nl from outside of xfrm_user by RCU, check that the socket is present in xfrm_aevent_is_on and set it to NULL when unloading xfrm_user. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/net/xfrm.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/xfrm.h b/include/net/xfrm.h index 786371365f2..61b7504fc2b 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1001,7 +1001,15 @@ static inline int xfrm_policy_id2dir(u32 index) static inline int xfrm_aevent_is_on(void) { - return netlink_has_listeners(xfrm_nl,XFRMNLGRP_AEVENTS); + struct sock *nlsk; + int ret = 0; + + rcu_read_lock(); + nlsk = rcu_dereference(xfrm_nl); + if (nlsk) + ret = netlink_has_listeners(nlsk, XFRMNLGRP_AEVENTS); + rcu_read_unlock(); + return ret; } static inline void xfrm_aevent_doreplay(struct xfrm_state *x) -- cgit v1.2.3