3 files changed, 26 insertions, 11 deletions

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 <linux/file.h>
 #include <linux/binfmts.h>
 #include <linux/nsproxy.h>
+#include <linux/pid_namespace.h>
 #include <linux/ptrace.h>
 #include <linux/profile.h>
 #include <linux/mount.h>
@@ -48,7 +49,6 @@
 #include <asm/mmu_context.h>
 
 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;
diff --git a/kernel/pid.c b/kernel/pid.c
index 1d9cc268b499..2efe9d8d367b 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -65,7 +65,8 @@ struct pid_namespace init_pid_ns = {
         .pidmap = {
                 [ 0 ... PIDMAP_ENTRIES-1] = { ATOMIC_INIT(BITS_PER_PAGE), NULL }
         },
-        .last_pid = 0
+        .last_pid = 0,
+        .child_reaper = &init_task
 };
 
 /*
diff --git a/kernel/signal.c b/kernel/signal.c
index 9eac4db60eda..1921ffdc5e77 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -24,6 +24,9 @@
 #include <linux/signal.h>
 #include <linux/capability.h>
 #include <linux/freezer.h>
+#include <linux/pid_namespace.h>
+#include <linux/nsproxy.h>
+
 #include <asm/param.h>
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
@@ -1877,8 +1880,12 @@ relock:
                 if (sig_kernel_ignore(signr)) /* Default is nothing. */
                         continue;
 
-                /* Init gets no signals it doesn't want.  */
-                if (current == child_reaper)
+                /*
+                 * Init of a pid space gets no signals it doesn't want from
+                 * within that pid space. It can of course get signals from
+                 * its parent pid space.
+                 */
+                if (current == child_reaper(current))
                         continue;
 
                 if (sig_kernel_stop(signr)) {