From e7b0a61b7929632d36cf052d9e2820ef0a9c1bfe Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:04:56 -0800 Subject: [PATCH] security: Apply lockdep-based checking to rcu_dereference() uses Apply lockdep-ified RCU primitives to key_gc_keyring() and keyring_destroy(). Cc: David Howells Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-12-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- security/keys/gc.c | 3 ++- security/keys/keyring.c | 4 +++- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/security/keys/gc.c b/security/keys/gc.c index 4770be375ffe..19902319d097 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -77,7 +77,8 @@ static bool key_gc_keyring(struct key *keyring, time_t limit) goto dont_gc; /* scan the keyring looking for dead keys */ - klist = rcu_dereference(keyring->payload.subscriptions); + klist = rcu_dereference_check(keyring->payload.subscriptions, + lockdep_is_held(&key_serial_lock)); if (!klist) goto dont_gc; diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 8ec02746ca99..e814d2109f8e 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -151,7 +151,9 @@ static void keyring_destroy(struct key *keyring) write_unlock(&keyring_name_lock); } - klist = rcu_dereference(keyring->payload.subscriptions); + klist = rcu_dereference_check(keyring->payload.subscriptions, + rcu_read_lock_held() || + atomic_read(&keyring->usage) == 0); if (klist) { for (loop = klist->nkeys - 1; loop >= 0; loop--) key_put(klist->keys[loop]); -- 2.20.1