The patch titled ptrace: permit ptracing of /sbin/init has been added to the -mm tree. Its filename is ptrace-allow-to-ptrace-sbin-init.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: ptrace: permit ptracing of /sbin/init From: Oleg Nesterov <oleg@xxxxxxxxxx> Afaics, currently there are no kernel problems with ptracing init, it can't lose SIGNAL_UNKILLABLE flag and be killed/stopped by accident. The ability to strace/debug init can be very useful if you try to figure out why it does not work as expected. However, admin should know what he does, "gdb /sbin/init 1" stops init, it can't reap orphaned zombies or take care of /etc/inittab until continued. It is even possible to crash init (and thus the whole system) if you wish, ptracer has full control. See also the long discussion: http://marc.info/?t=120628018600001 Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Acked-by: Roland McGrath <roland@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/ptrace.c | 8 -------- 1 file changed, 8 deletions(-) diff -puN kernel/ptrace.c~ptrace-allow-to-ptrace-sbin-init kernel/ptrace.c --- a/kernel/ptrace.c~ptrace-allow-to-ptrace-sbin-init +++ a/kernel/ptrace.c @@ -168,8 +168,6 @@ int ptrace_attach(struct task_struct *ta audit_ptrace(task); retval = -EPERM; - if (task->pid <= 1) - goto out; if (same_thread_group(task, current)) goto out; @@ -517,12 +515,6 @@ struct task_struct *ptrace_get_task_stru { struct task_struct *child; - /* - * Tracing init is not allowed. - */ - if (pid == 1) - return ERR_PTR(-EPERM); - read_lock(&tasklist_lock); child = find_task_by_vpid(pid); if (child) _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are x86-handle_vm86_trap-cleanup.patch git-hrt.patch mmap_region-cleanup-the-final-vma_merge-related-code.patch kthread-call-wake_up_process-without-the-lock-being-held.patch remove-unused-variable-from-send_signal.patch turn-legacy_queue-macro-into-static-inline-function.patch consolidate-checking-for-ignored-legacy-signals.patch consolidate-checking-for-ignored-legacy-signals-simplify.patch signals-do_signal_stop-use-signal_group_exit.patch signals-do_group_exit-use-signal_group_exit-more-consistently.patch lock_task_sighand-add-rcu-lock-unlock.patch k_getrusage-dont-take-rcu_read_lock.patch do_task_stat-dont-take-rcu_read_lock.patch signals-consolidate-checks-for-whether-or-not-to-ignore-a-signal.patch signals-clean-dequeue_signal-from-excess-checks-and-assignments.patch signals-consolidate-send_sigqueue-and-send_group_sigqueue.patch signals-cleanup-security_task_kill-usage-implementation.patch signals-re-assign-cld_continued-notification-from-the-sender-to-reciever.patch kill_pid_info-dont-take-now-unneeded-tasklist_lock.patch handle_stop_signal-unify-partial-full-stop-handling.patch handle_stop_signal-use-the-cached-p-signal-value.patch get_signal_to_deliver-use-the-cached-signal-sighand-values.patch signals-send_sigqueue-dont-take-rcu-lock.patch signals-send_sigqueue-dont-forget-about-handle_stop_signal.patch signals-__group_complete_signal-cache-the-value-of-p-signal.patch signals-send_group_sigqueue-dont-take-tasklist_lock.patch signals-move-handle_stop_signal-into-send_signal.patch signals-do_tkill-dont-use-tasklist_lock.patch signals-do_tkill-dont-use-tasklist_lock-comment.patch signals-send_sig_info-dont-take-tasklist_lock.patch signals-microoptimize-the-usage-of-curr_target.patch signals-move-the-definition-of-__group_complete_signal-up.patch signals-change-send_signal-do_send_sigqueue-to-take-boolean-group-parameter.patch signals-use-__group_complete_signal-for-the-specific-signals-too.patch signals-fold-complete_signal-into-send_signal-do_send_sigqueue.patch signals-unify-send_sigqueue-send_group_sigqueue-completely.patch signals-join-send_sigqueue-with-send_group_sigqueue.patch signals-handle_stop_signal-dont-worry-about-sigkill.patch signals-cleanup-the-usage-of-print_fatal_signal.patch signals-fold-sig_ignored-into-handle_stop_signal.patch signals-fold-sig_ignored-into-handle_stop_signal-comment.patch signals-document-cld_continued-notification-mechanics.patch signals-document-cld_continued-notification-mechanics-more.patch signals-send_signal-be-paranoid-about-signalfd_notify.patch signals-check_kill_permission-check-session-under-tasklist_lock.patch signals-check_kill_permission-remove-tasklist_lock.patch signals-fix-sbin-init-protection-from-unwanted-signals.patch signals-de_thread-simplify-the-child_reaper-switching.patch signals-allow-the-kernel-to-actually-kill-sbin-init.patch ptrace-introduce-task_detached-helper.patch reparent_thread-use-same_thread_group.patch document-de_thread-with-exit_notify-connection.patch ptrace-introduce-ptrace_reparented-helper.patch ptrace-__ptrace_unlink-use-the-ptrace_reparented-helper.patch ptrace-ptrace_attach-use-send_sig_info-instead-force_sig_specific.patch ptrace-allow-to-ptrace-sbin-init.patch workqueues-shrink-cpu_populated_map-when-cpu-dies.patch workqueues-shrink-cpu_populated_map-when-cpu-dies-fix.patch cleanup_workqueue_thread-remove-the-unneeded-cpu-parameter.patch simplify-cpu_hotplug_begin-put_online_cpus.patch redo-locking-of-tty-pgrp.patch resume-tty-on-susp-and-fix-crnl-order-in-n_tty-line-discipline.patch tty_io-fix-remaining-pid-struct-locking.patch tty_io-fix-remaining-pid-struct-locking-small-cleanup.patch procfs-task-exe-symlink.patch procfs-task-exe-symlink-fix.patch procfs-task-exe-symlink-fix-2.patch free_pidmap-turn-it-into-free_pidmapstruct-upid.patch pids-de_thread-dont-clear-session-pgrp-pids-for-the-old-leader.patch pids-introduce-change_pid-helper.patch pids-sys_setpgid-use-change_pid-helper.patch pids-__set_special_pids-use-change_pid-helper.patch pids-sys_getsid-fix-unsafe-pid-usage-fix-possible-0-instead-of-esrch.patch pids-sys_getpgid-fix-unsafe-pid-usage-s-tasklist-rcu.patch put_pid-make-sure-we-dont-free-the-live-pid.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html