The core ptrace access checking routine already holds the task lock, so there is no need to use get_task_comm() which just tries to take the lock again. Drop its use and access current->comm directly.
Reported-by: Fengguang Wu <[email protected]> Suggested-by: Oleg Nesterov <[email protected]> Cc: [email protected] Signed-off-by: Kees Cook <[email protected]> --- security/yama/yama_lsm.c | 6 ++---- 1 files changed, 2 insertions(+), 4 deletions(-) diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c index 83554ee..20a68ca 100644 --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -279,12 +279,10 @@ static int yama_ptrace_access_check(struct task_struct *child, } if (rc) { - char name[sizeof(current->comm)]; + /* task_lock is held by the caller, so use comm directly. */ printk_ratelimited(KERN_NOTICE "ptrace of pid %d was attempted by: %s (pid %d)\n", - child->pid, - get_task_comm(name, current), - current->pid); + child->pid, current->comm, current->pid); } return rc; -- 1.7.0.4 -- Kees Cook Chrome OS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
