linux/net/xfrm
Eric Dumazet ef8531b64c xfrm: fix RCU bugs
This patch reverts commit 56892261ed (xfrm: Use rcu_dereference_bh to
deference pointer protected by rcu_read_lock_bh), and fixes bugs
introduced in commit 418a99ac6a ( Replace rwlock on xfrm_policy_afinfo
with rcu )

1) We properly use RCU variant in this file, not a mix of RCU/RCU_BH

2) We must defer some writes after the synchronize_rcu() call or a reader
 can crash dereferencing NULL pointer.

3) Now we use the xfrm_policy_afinfo_lock spinlock only from process
context, we no longer need to block BH in xfrm_policy_register_afinfo()
and xfrm_policy_unregister_afinfo()

4) Can use RCU_INIT_POINTER() instead of rcu_assign_pointer() in
xfrm_policy_unregister_afinfo()

5) Remove a forward inline declaration (xfrm_policy_put_afinfo()),
  and also move xfrm_policy_get_afinfo() declaration.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Fan Du <fan.du@windriver.com>
Cc: Priyanka Jain <Priyanka.Jain@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-22 22:39:46 -07:00
..
Kconfig xfrm: make xfrm_algo.c a module 2012-05-15 13:13:34 -04:00
Makefile xfrm: make xfrm_algo.c a module 2012-05-15 13:13:34 -04:00
xfrm_algo.c xfrm_algo: drop an unnecessary inclusion 2012-05-15 13:13:34 -04:00
xfrm_hash.c net: allow GFP_HIGHMEM in __vmalloc() 2010-11-21 10:04:04 -08:00
xfrm_hash.h net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
xfrm_input.c xfrm: Perform a replay check after return from async codepaths 2011-09-21 15:20:57 -04:00
xfrm_ipcomp.c net: add skb frag size accessors 2011-10-19 03:10:46 -04:00
xfrm_output.c xfrm: Remove unused xfrm_state from xfrm_state_check_space 2012-03-22 19:29:58 -04:00
xfrm_policy.c xfrm: fix RCU bugs 2012-08-22 22:39:46 -07:00
xfrm_proc.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
xfrm_replay.c xfrm: Access the replay notify functions via the registered callbacks 2012-03-22 19:29:58 -04:00
xfrm_state.c xfrm: remove redundant parameter "int dir" in struct xfrm_mgr.acquire 2012-08-15 15:13:30 -07:00
xfrm_sysctl.c net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
xfrm_user.c xfrm: remove redundant parameter "int dir" in struct xfrm_mgr.acquire 2012-08-15 15:13:30 -07:00