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    Subject[patch 9/9] security: Fix invalid rcu assumptions in comments
    1) held spinlocks are not equivalent to rcu_read_lock

    2) access to current_cred() is safe as only current can modify its
    own credentials.

    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    Cc: James Morris <jmorris@namei.org>
    Cc: linux-security-module@vger.kernel.org

    ---
    security/keys/permission.c | 3 +--
    security/keys/proc.c | 2 --
    2 files changed, 1 insertion(+), 4 deletions(-)

    Index: linux-2.6-tip/security/keys/permission.c
    ===================================================================
    --- linux-2.6-tip.orig/security/keys/permission.c
    +++ linux-2.6-tip/security/keys/permission.c
    @@ -23,8 +23,7 @@
    * Check to see whether permission is granted to use a key in the desired way,
    * but permit the security modules to override.
    *
    - * The caller must hold either a ref on cred or must hold the RCU readlock or a
    - * spinlock.
    + * The caller must hold either a ref on cred or must hold the RCU readlock.
    */
    int key_task_permission(const key_ref_t key_ref, const struct cred *cred,
    key_perm_t perm)
    Index: linux-2.6-tip/security/keys/proc.c
    ===================================================================
    --- linux-2.6-tip.orig/security/keys/proc.c
    +++ linux-2.6-tip/security/keys/proc.c
    @@ -194,8 +194,6 @@ static int proc_keys_show(struct seq_fil

    /* check whether the current task is allowed to view the key (assuming
    * non-possession)
    - * - the caller holds a spinlock, and thus the RCU read lock, making our
    - * access to __current_cred() safe
    */
    rc = key_task_permission(make_key_ref(key, 0), current_cred(),
    KEY_VIEW);



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