KEYS: Fix an RCU warning in the reading of user keys
authorDavid Howells <dhowells@redhat.com>
Wed, 21 Apr 2010 16:36:35 +0000 (17:36 +0100)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Tue, 4 May 2010 16:24:58 +0000 (09:24 -0700)
commite35ec2d2c1fc45dd3e46dde74bb0c4c4366125bf
treed5df7afffd9b258617fcd53b00a6eee790c1b831
parentbfeb0360de7713de8240cafd7ecf6058b6dbea0b
KEYS: Fix an RCU warning in the reading of user keys

Fix an RCU warning in the reading of user keys:

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
security/keys/user_defined.c:202 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 keyctl/3637:
 #0:  (&key->sem){+++++.}, at: [<ffffffff811a80ae>] keyctl_read_key+0x9c/0xcf

stack backtrace:
Pid: 3637, comm: keyctl Not tainted 2.6.34-rc5-cachefs #18
Call Trace:
 [<ffffffff81051f6c>] lockdep_rcu_dereference+0xaa/0xb2
 [<ffffffff811aa55f>] user_read+0x47/0x91
 [<ffffffff811a80be>] keyctl_read_key+0xac/0xcf
 [<ffffffff811a8a06>] sys_keyctl+0x75/0xb7
 [<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
security/keys/user_defined.c