From: David Howells Date: Tue, 13 Dec 2011 14:49:04 +0000 (+0000) Subject: SELinux: Fix RCU deref check warning in sel_netport_insert() X-Git-Tag: v3.2-rc7~19 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=50345f1ea9cda4618d9c26e590a97ecd4bc7ac75;p=platform%2Fupstream%2Fkernel-adaptation-pc.git SELinux: Fix RCU deref check warning in sel_netport_insert() Fix the following bug in sel_netport_insert() where rcu_dereference() should be rcu_dereference_protected() as sel_netport_lock is held. =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- security/selinux/netport.c:127 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 ossec-rootcheck/3323: #0: (sel_netport_lock){+.....}, at: [] sel_netport_sid+0xbb/0x226 stack backtrace: Pid: 3323, comm: ossec-rootcheck Not tainted 3.1.0-rc8-fsdevel+ #1095 Call Trace: [] lockdep_rcu_dereference+0xa7/0xb0 [] sel_netport_sid+0x1b7/0x226 [] ? sel_netport_avc_callback+0xbc/0xbc [] selinux_socket_bind+0x115/0x230 [] ? might_fault+0x4e/0x9e [] ? might_fault+0x97/0x9e [] security_socket_bind+0x11/0x13 [] sys_bind+0x56/0x95 [] ? sysret_check+0x27/0x62 [] ? trace_hardirqs_on_caller+0x11e/0x155 [] ? audit_syscall_entry+0x17b/0x1ae [] ? trace_hardirqs_on_thunk+0x3a/0x3f [] system_call_fastpath+0x16/0x1b Signed-off-by: David Howells Acked-by: Paul Moore Acked-by: Eric Dumazet Cc: stable@kernel.org Signed-off-by: James Morris --- diff --git a/security/selinux/netport.c b/security/selinux/netport.c index 0b62bd1..7b9eb1f 100644 --- a/security/selinux/netport.c +++ b/security/selinux/netport.c @@ -123,7 +123,9 @@ static void sel_netport_insert(struct sel_netport *port) if (sel_netport_hash[idx].size == SEL_NETPORT_HASH_BKT_LIMIT) { struct sel_netport *tail; tail = list_entry( - rcu_dereference(sel_netport_hash[idx].list.prev), + rcu_dereference_protected( + sel_netport_hash[idx].list.prev, + lockdep_is_held(&sel_netport_lock)), struct sel_netport, list); list_del_rcu(&tail->list); kfree_rcu(tail, rcu);