On 05/04, Roland McGrath wrote: > > This looks good to me overall. It might be worth slicing it into two or > more patches, just for bisect paranoia. (e.g. PF_KTHREAD; task_lock in > ptrace_attach; task_lock in ptrace_traceme.)
OK, > I think it merits a comment that the PF_KTHREAD check does not need any > interlock because daemonize() will detach ptrace via reparent_to_kthreadd() > after it sets PF_KTHREAD. (vs the old ->mm check under task_lock.) Agreed, but actually the patch doesn't make the difference wrt daemonize(). currently ptrace_attach() can take task_lock() just before daemonize() calls exit_mm(). > It is worth noting that this changes the security_ptrace_traceme() call so > it's no longer under task_lock(). I can't see any way the LSM hooks care, > but it is a change. Yes, good point. > You also didn't mention the s/|=/=/ changes. Those are correct, we've > already agreed, but the commit log should mention that this subtle change > was intentional. Yes! Forgot to mention, thanks. Oleg.
