Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[net-next-2.6.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 51ad0b0b72664ad327c042c33272e90630ec932b..4c20fff8c13a2caae048bc9f2b719bdaf5582dcf 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -434,6 +434,14 @@ __setup("coredump_filter=", coredump_filter_setup);
 
 #include <linux/init_task.h>
 
+static void mm_init_aio(struct mm_struct *mm)
+{
+#ifdef CONFIG_AIO
+       spin_lock_init(&mm->ioctx_lock);
+       INIT_HLIST_HEAD(&mm->ioctx_list);
+#endif
+}
+
 static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
 {
        atomic_set(&mm->mm_users, 1);
@@ -447,10 +455,9 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
        set_mm_counter(mm, file_rss, 0);
        set_mm_counter(mm, anon_rss, 0);
        spin_lock_init(&mm->page_table_lock);
-       spin_lock_init(&mm->ioctx_lock);
-       INIT_HLIST_HEAD(&mm->ioctx_list);
        mm->free_area_cache = TASK_UNMAPPED_BASE;
        mm->cached_hole_size = ~0UL;
+       mm_init_aio(mm);
        mm_init_owner(mm, p);
 
        if (likely(!mm_alloc_pgd(mm))) {
@@ -511,6 +518,8 @@ void mmput(struct mm_struct *mm)
                        spin_unlock(&mmlist_lock);
                }
                put_swap_token(mm);
+               if (mm->binfmt)
+                       module_put(mm->binfmt->module);
                mmdrop(mm);
        }
 }
@@ -561,12 +570,18 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 
        /* Get rid of any futexes when releasing the mm */
 #ifdef CONFIG_FUTEX
-       if (unlikely(tsk->robust_list))
+       if (unlikely(tsk->robust_list)) {
                exit_robust_list(tsk);
+               tsk->robust_list = NULL;
+       }
 #ifdef CONFIG_COMPAT
-       if (unlikely(tsk->compat_robust_list))
+       if (unlikely(tsk->compat_robust_list)) {
                compat_exit_robust_list(tsk);
+               tsk->compat_robust_list = NULL;
+       }
 #endif
+       if (unlikely(!list_empty(&tsk->pi_state_list)))
+               exit_pi_state_list(tsk);
 #endif
 
        /* Get rid of any cached register state */
@@ -636,9 +651,14 @@ struct mm_struct *dup_mm(struct task_struct *tsk)
        mm->hiwater_rss = get_mm_rss(mm);
        mm->hiwater_vm = mm->total_vm;
 
+       if (mm->binfmt && !try_module_get(mm->binfmt->module))
+               goto free_pt;
+
        return mm;
 
 free_pt:
+       /* don't put binfmt in mmput, we haven't got module yet */
+       mm->binfmt = NULL;
        mmput(mm);
 
 fail_nomem:
@@ -979,6 +999,16 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        if ((clone_flags & CLONE_SIGHAND) && !(clone_flags & CLONE_VM))
                return ERR_PTR(-EINVAL);
 
+       /*
+        * Siblings of global init remain as zombies on exit since they are
+        * not reaped by their parent (swapper). To solve this and to avoid
+        * multi-rooted process trees, prevent global and container-inits
+        * from creating siblings.
+        */
+       if ((clone_flags & CLONE_PARENT) &&
+                               current->signal->flags & SIGNAL_UNKILLABLE)
+               return ERR_PTR(-EINVAL);
+
        retval = security_task_create(clone_flags);
        if (retval)
                goto fork_out;
@@ -1020,9 +1050,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        if (!try_module_get(task_thread_info(p)->exec_domain->module))
                goto bad_fork_cleanup_count;
 
-       if (p->binfmt && !try_module_get(p->binfmt->module))
-               goto bad_fork_cleanup_put_domain;
-
        p->did_exec = 0;
        delayacct_tsk_init(p);  /* Must remain after dup_task_struct() */
        copy_flags(clone_flags, p);
@@ -1310,9 +1337,6 @@ bad_fork_cleanup_cgroup:
 #endif
        cgroup_exit(p, cgroup_callbacks_done);
        delayacct_tsk_free(p);
-       if (p->binfmt)
-               module_put(p->binfmt->module);
-bad_fork_cleanup_put_domain:
        module_put(task_thread_info(p)->exec_domain->module);
 bad_fork_cleanup_count:
        atomic_dec(&p->cred->user->processes);