From 84d737866e2babdeab0c6b18ea155c6a649663b8 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Fri, 8 Dec 2006 02:38:01 -0800 Subject: [PATCH] add child reaper to pid_namespace Add a per pid_namespace child-reaper. This is needed so processes are reaped within the same pid space and do not spill over to the parent pid space. Its also needed so containers preserve existing semantic that pid == 1 would reap orphaned children. This is based on Eric Biederman's patch: http://lkml.org/lkml/2006/2/6/285 Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Cedric Le Goater Cc: Kirill Korotaev Cc: Eric W. Biederman Cc: Herbert Poetzl Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/exit.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) (limited to 'kernel/exit.c') diff --git a/kernel/exit.c b/kernel/exit.c index 28d9feedfd27..fd0e067952ab 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -48,7 +49,6 @@ #include extern void sem_exit (void); -extern struct task_struct *child_reaper; static void exit_mm(struct task_struct * tsk); @@ -260,7 +260,8 @@ static int has_stopped_jobs(int pgrp) } /** - * reparent_to_init - Reparent the calling kernel thread to the init task. + * reparent_to_init - Reparent the calling kernel thread to the init task + * of the pid space that the thread belongs to. * * If a kernel thread is launched as a result of a system call, or if * it ever exits, it should generally reparent itself to init so that @@ -278,8 +279,8 @@ static void reparent_to_init(void) ptrace_unlink(current); /* Reparent to init */ remove_parent(current); - current->parent = child_reaper; - current->real_parent = child_reaper; + current->parent = child_reaper(current); + current->real_parent = child_reaper(current); add_parent(current); /* Set the exit signal to SIGCHLD so we signal init on exit */ @@ -662,7 +663,8 @@ reparent_thread(struct task_struct *p, struct task_struct *father, int traced) * When we die, we re-parent all our children. * Try to give them to another thread in our thread * group, and if no such member exists, give it to - * the global child reaper process (ie "init") + * the child reaper process (ie "init") in our pid + * space. */ static void forget_original_parent(struct task_struct *father, struct list_head *to_release) @@ -673,7 +675,7 @@ forget_original_parent(struct task_struct *father, struct list_head *to_release) do { reaper = next_thread(reaper); if (reaper == father) { - reaper = child_reaper; + reaper = child_reaper(father); break; } } while (reaper->exit_state); @@ -859,8 +861,13 @@ fastcall NORET_TYPE void do_exit(long code) panic("Aiee, killing interrupt handler!"); if (unlikely(!tsk->pid)) panic("Attempted to kill the idle task!"); - if (unlikely(tsk == child_reaper)) - panic("Attempted to kill init!"); + if (unlikely(tsk == child_reaper(tsk))) { + if (tsk->nsproxy->pid_ns != &init_pid_ns) + tsk->nsproxy->pid_ns->child_reaper = init_pid_ns.child_reaper; + else + panic("Attempted to kill init!"); + } + if (unlikely(current->ptrace & PT_TRACE_EXIT)) { current->ptrace_message = code; -- cgit v1.2.3