commit 425fb2b4bf5dde24be4a82e9a2c344bb49ac92e4
author Pavel Emelyanov <xemul@openvz.org> Thu Oct 18 23:40:07 2007 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> Fri Oct 19 11:53:39 2007 -0700
tree 04cdf3042ee0f593b243c6402f2ce3cacac5cc2d
parent 198fe21b0a17fe9c68cb519ecc566534b04f122b

pid namespaces: move alloc_pid() lower in copy_process()

When we create new namespace we will need to allocate the struct pid, that
will have one extra struct upid in array, comparing to the parent.

Thus we need to know the new namespace (if any) in alloc_pid() to init this
struct upid properly, so move the alloc_pid() call lower in copy_process().

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 984d259..bab3419 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1040,16 +1040,9 @@
 	if (p->binfmt && !try_module_get(p->binfmt->module))
 		goto bad_fork_cleanup_put_domain;
 
-	if (pid != &init_struct_pid) {
-		pid = alloc_pid(task_active_pid_ns(p));
-		if (!pid)
-			goto bad_fork_put_binfmt_module;
-	}
-
 	p->did_exec = 0;
 	delayacct_tsk_init(p);	/* Must remain after dup_task_struct() */
 	copy_flags(clone_flags, p);
-	p->pid = pid_nr(pid);
 	retval = -EFAULT;
 	if (clone_flags & CLONE_PARENT_SETTID)
 		if (put_user(p->pid, parent_tidptr))
@@ -1133,10 +1126,6 @@
 	p->blocked_on = NULL; /* not blocked yet */
 #endif
 
-	p->tgid = p->pid;
-	if (clone_flags & CLONE_THREAD)
-		p->tgid = current->tgid;
-
 	if ((retval = security_task_alloc(p)))
 		goto bad_fork_cleanup_policy;
 	if ((retval = audit_alloc(p)))
@@ -1162,6 +1151,18 @@
 	if (retval)
 		goto bad_fork_cleanup_namespaces;
 
+	if (pid != &init_struct_pid) {
+		retval = -ENOMEM;
+		pid = alloc_pid(task_active_pid_ns(p));
+		if (!pid)
+			goto bad_fork_cleanup_namespaces;
+	}
+
+	p->pid = pid_nr(pid);
+	p->tgid = p->pid;
+	if (clone_flags & CLONE_THREAD)
+		p->tgid = current->tgid;
+
 	p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
 	/*
 	 * Clear TID on mm_release()?
@@ -1259,7 +1260,7 @@
 		spin_unlock(&current->sighand->siglock);
 		write_unlock_irq(&tasklist_lock);
 		retval = -ERESTARTNOINTR;
-		goto bad_fork_cleanup_namespaces;
+		goto bad_fork_free_pid;
 	}
 
 	if (clone_flags & CLONE_THREAD) {
@@ -1308,6 +1309,9 @@
 	cgroup_post_fork(p);
 	return p;
 
+bad_fork_free_pid:
+	if (pid != &init_struct_pid)
+		free_pid(pid);
 bad_fork_cleanup_namespaces:
 	exit_task_namespaces(p);
 bad_fork_cleanup_keys:
@@ -1337,9 +1341,6 @@
 	cgroup_exit(p, cgroup_callbacks_done);
 bad_fork_cleanup_delays_binfmt:
 	delayacct_tsk_free(p);
-	if (pid != &init_struct_pid)
-		free_pid(pid);
-bad_fork_put_binfmt_module:
 	if (p->binfmt)
 		module_put(p->binfmt->module);
 bad_fork_cleanup_put_domain: