On 06/08, Oleg Nesterov wrote: > > OK. Thanks a lot Eric for your explanations. Yes. but may I ask another one? Shouldn't copy_process()->audit_alloc(tsk) path do clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT) if it doesn't set tsk->audit_context? I can be easily wrong, but afaics otherwise the child can run with TIF_SYSCALL_AUDIT bit copied from parent's thread_info by dup_task_struct()->setup_thread_stack() and without ->audit_context, right? For what? Any other reason why audit_syscall_entry() checks context != NULL? IOW. Any reason the patch below is wrong? I am just curious, thanks. Oleg. --- x/kernel/auditsc.c +++ x/kernel/auditsc.c @@ -885,6 +885,8 @@ int audit_alloc(struct task_struct *tsk) if (likely(!audit_ever_enabled)) return 0; /* Return if not auditing. */ + clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); + state = audit_filter_task(tsk, &key); if (likely(state == AUDIT_DISABLED)) return 0; @@ -1591,9 +1593,7 @@ void audit_syscall_entry(int arch, int m struct audit_context *context = tsk->audit_context; enum audit_state state; - if (unlikely(!context)) - return; - + BUG_ON(!context); /* * This happens only on certain architectures that make system * calls in kernel_thread via the entry.S interface, instead of
