lkml.org 
[lkml]   [2011]   [Apr]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subjectsuspicious rcu_dereference_check in security/selinux/netnode.c
 ===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
security/selinux/netnode.c:193 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
1 lock held by a.out/2018:
#0: (sel_netnode_lock){+.....}, at: [<ffffffff81212ab7>] sel_netnode_sid+0x9e/0x267

stack backtrace:
Pid: 2018, comm: a.out Not tainted 2.6.39-rc4+ #3
Call Trace:
[<ffffffff81084908>] lockdep_rcu_dereference+0xa8/0xb0
[<ffffffff81212c0d>] sel_netnode_sid+0x1f4/0x267
[<ffffffff81212a19>] ? sel_netnode_find+0xe3/0xe3
[<ffffffff8120d564>] selinux_socket_bind+0x1cf/0x26f
[<ffffffff81086c08>] ? lock_release+0x181/0x18e
[<ffffffff81100db8>] ? might_fault+0xa5/0xac
[<ffffffff81100d6f>] ? might_fault+0x5c/0xac
[<ffffffff812073f1>] security_socket_bind+0x16/0x18
[<ffffffff813ee0e9>] sys_bind+0x73/0xcf
[<ffffffff814c5d7a>] ? sysret_check+0x2e/0x69
[<ffffffff810870cf>] ? trace_hardirqs_on_caller+0x10b/0x12f
[<ffffffff810a9efb>] ? audit_syscall_entry+0x11c/0x148
[<ffffffff81255e2e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[<ffffffff814c5d42>] system_call_fastpath+0x16/0x1b


something like this perhaps ?

Dave

diff --git a/security/selinux/netnode.c b/security/selinux/netnode.c
index 65ebfe9..d0c38ba 100644
--- a/security/selinux/netnode.c
+++ b/security/selinux/netnode.c
@@ -188,9 +188,11 @@ static void sel_netnode_insert(struct sel_netnode *node)
list_add_rcu(&node->list, &sel_netnode_hash[idx].list);
if (sel_netnode_hash[idx].size == SEL_NETNODE_HASH_BKT_LIMIT) {
struct sel_netnode *tail;
+ rcu_read_lock();
tail = list_entry(
rcu_dereference(sel_netnode_hash[idx].list.prev),
struct sel_netnode, list);
+ rcu_read_unlock();
list_del_rcu(&tail->list);
call_rcu(&tail->rcu, sel_netnode_free);
} else

\
 
 \ /
  Last update: 2011-04-20 20:39    [W:0.241 / U:0.208 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site