pidns: call pid_ns_prepare_proc() from create_pid_namespace()
Reorganize proc_get_sb() so it can be called before the struct pid of the
first process is allocated.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/root.c b/fs/proc/root.c
index ef9fa8e..e5e2bfa 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -43,17 +43,6 @@
struct pid_namespace *ns;
struct proc_inode *ei;
- if (proc_mnt) {
- /* Seed the root directory with a pid so it doesn't need
- * to be special in base.c. I would do this earlier but
- * the only task alive when /proc is mounted the first time
- * is the init_task and it doesn't have any pids.
- */
- ei = PROC_I(proc_mnt->mnt_sb->s_root->d_inode);
- if (!ei->pid)
- ei->pid = find_get_pid(1);
- }
-
if (flags & MS_KERNMOUNT)
ns = (struct pid_namespace *)data;
else
@@ -71,16 +60,16 @@
return ERR_PTR(err);
}
- ei = PROC_I(sb->s_root->d_inode);
- if (!ei->pid) {
- rcu_read_lock();
- ei->pid = get_pid(find_pid_ns(1, ns));
- rcu_read_unlock();
- }
-
sb->s_flags |= MS_ACTIVE;
}
+ ei = PROC_I(sb->s_root->d_inode);
+ if (!ei->pid) {
+ rcu_read_lock();
+ ei->pid = get_pid(find_pid_ns(1, ns));
+ rcu_read_unlock();
+ }
+
return dget(sb->s_root);
}
diff --git a/kernel/fork.c b/kernel/fork.c
index 17aed43..457fff2 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1187,12 +1187,6 @@
pid = alloc_pid(p->nsproxy->pid_ns);
if (!pid)
goto bad_fork_cleanup_io;
-
- if (clone_flags & CLONE_NEWPID) {
- retval = pid_ns_prepare_proc(p->nsproxy->pid_ns);
- if (retval < 0)
- goto bad_fork_free_pid;
- }
}
p->pid = pid_nr(pid);
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index a5aff94..e9c9adc 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -14,6 +14,7 @@
#include <linux/err.h>
#include <linux/acct.h>
#include <linux/slab.h>
+#include <linux/proc_fs.h>
#define BITS_PER_PAGE (PAGE_SIZE*8)
@@ -72,7 +73,7 @@
{
struct pid_namespace *ns;
unsigned int level = parent_pid_ns->level + 1;
- int i;
+ int i, err = -ENOMEM;
ns = kmem_cache_zalloc(pid_ns_cachep, GFP_KERNEL);
if (ns == NULL)
@@ -96,14 +97,20 @@
for (i = 1; i < PIDMAP_ENTRIES; i++)
atomic_set(&ns->pidmap[i].nr_free, BITS_PER_PAGE);
+ err = pid_ns_prepare_proc(ns);
+ if (err)
+ goto out_put_parent_pid_ns;
+
return ns;
+out_put_parent_pid_ns:
+ put_pid_ns(parent_pid_ns);
out_free_map:
kfree(ns->pidmap[0].page);
out_free:
kmem_cache_free(pid_ns_cachep, ns);
out:
- return ERR_PTR(-ENOMEM);
+ return ERR_PTR(err);
}
static void destroy_pid_namespace(struct pid_namespace *ns)