I reported this a year ago (https://lkml.org/lkml/2011/4/20/308). It's still a problem apparently ... =============================== [ INFO: suspicious RCU usage. ] 3.5.0-rc1+ #63 Not tainted ------------------------------- security/selinux/netnode.c:178 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by trinity-child1/8750: #0: (sel_netnode_lock){+.....}, at: [<ffffffff812d8f8a>] sel_netnode_sid+0x16a/0x3e0 stack backtrace: Pid: 8750, comm: trinity-child1 Not tainted 3.5.0-rc1+ #63 Call Trace: [<ffffffff810cec2d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff812d91d1>] sel_netnode_sid+0x3b1/0x3e0 [<ffffffff812d8e20>] ? sel_netnode_find+0x1a0/0x1a0 [<ffffffff812d24a6>] selinux_socket_bind+0xf6/0x2c0 [<ffffffff810cd1dd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff810cdb55>] ? lock_release_holdtime.part.9+0x15/0x1a0 [<ffffffff81093841>] ? lock_hrtimer_base+0x31/0x60 [<ffffffff812c9536>] security_socket_bind+0x16/0x20 [<ffffffff815550ca>] sys_bind+0x7a/0x100 [<ffffffff816c03d5>] ? sysret_check+0x22/0x5d [<ffffffff810d392d>] ? trace_hardirqs_on_caller+0x10d/0x1a0 [<ffffffff8133b09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff816c03a9>] system_call_fastpath+0x16/0x1b This patch below does what Paul McKenney suggested in the previous thread. Signed-off-by: Dave Jones <davej@xxxxxxxxxx> Signed-off-by: Eric Paris <eparis@xxxxxxxxxx> --- security/selinux/netnode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/selinux/netnode.c b/security/selinux/netnode.c index e984d6f..3b66d89 100644 --- a/security/selinux/netnode.c +++ b/security/selinux/netnode.c @@ -174,7 +174,8 @@ static void sel_netnode_insert(struct sel_netnode *node) if (sel_netnode_hash[idx].size == SEL_NETNODE_HASH_BKT_LIMIT) { struct sel_netnode *tail; tail = list_entry( - rcu_dereference(sel_netnode_hash[idx].list.prev), + rcu_dereference_protected(sel_netnode_hash[idx].list.prev, + lockdep_is_held(&sel_netnode_lock)), struct sel_netnode, list); list_del_rcu(&tail->list); kfree_rcu(tail, rcu); -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@xxxxxxxxxxxxx with the words "unsubscribe selinux" without quotes as the message.
