linux_dsm_epyc7002/security/keys
David Howells cf8304e8f3 KEYS: Fix RCU handling in key_gc_keyring()
key_gc_keyring() needs to either hold the RCU read lock or hold the keyring
semaphore if it's going to scan the keyring's list.  Given that it only needs
to read the key list, and it's doing so under a spinlock, the RCU read lock is
the thing to use.

Furthermore, the RCU check added in e7b0a61b79 is
incorrect as holding the spinlock on key_serial_lock is not grounds for
assuming a keyring's pointer list can be read safely.  Instead, a simple
rcu_dereference() inside of the previously mentioned RCU read lock is what we
want.

Reported-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 11:39:23 +10:00
..
compat.c KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] 2009-09-02 21:29:22 +10:00
gc.c KEYS: Fix RCU handling in key_gc_keyring() 2010-05-05 11:39:23 +10:00
internal.h KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] 2009-09-02 21:29:22 +10:00
key.c KEYS: Fix garbage collector 2009-09-15 09:11:02 +10:00
keyctl.c Keys: KEYCTL_SESSION_TO_PARENT needs TIF_NOTIFY_RESUME architecture support 2009-12-17 09:27:59 +11:00
keyring.c keys: don't need to use RCU in keyring_read() as semaphore is held 2010-04-28 08:37:15 +10:00
Makefile KEYS: Add garbage collection for dead, revoked and expired keys. [try #6] 2009-09-02 21:29:11 +10:00
permission.c keys: consider user namespace in key_permission 2009-02-27 12:35:09 +11:00
proc.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
process_keys.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
request_key_auth.c CRED: Inaugurate COW credentials 2008-11-14 10:39:23 +11:00
request_key.c keys: the request_key() syscall should link an existing key to the dest keyring 2010-04-27 16:26:03 -07:00
sysctl.c sysctl: Drop & in front of every proc_handler. 2009-11-18 08:37:40 -08:00
user_defined.c KEYS: Fix an RCU warning in the reading of user keys 2010-05-05 11:38:52 +10:00