Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull namespace bugfixes from Eric Biederman:
 "This is three simple fixes against 3.9-rc1.  I have tested each of
  these fixes and verified they work correctly.

  The userns oops in key_change_session_keyring and the BUG_ON triggered
  by proc_ns_follow_link were found by Dave Jones.

  I am including the enhancement for mount to only trigger requests of
  filesystem modules here instead of delaying this for the 3.10 merge
  window because it is both trivial and the kind of change that tends to
  bit-rot if left untouched for two months."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: Use nd_jump_link in proc_ns_follow_link
  fs: Limit sys_mount to only request filesystem modules (Part 2).
  fs: Limit sys_mount to only request filesystem modules.
  userns: Stop oopsing in key_change_session_keyring

1 files changed, 6 insertions, 6 deletions

diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index b7a47196c8c3..66b51c0383da 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -118,7 +118,7 @@ static void *proc_ns_follow_link(struct dentry *dentry, struct nameidata *nd)
         struct super_block *sb = inode->i_sb;
         struct proc_inode *ei = PROC_I(inode);
         struct task_struct *task;
-        struct dentry *ns_dentry;
+        struct path ns_path;
         void *error = ERR_PTR(-EACCES);
 
         task = get_proc_task(inode);
@@ -128,14 +128,14 @@ static void *proc_ns_follow_link(struct dentry *dentry, struct nameidata *nd)
         if (!ptrace_may_access(task, PTRACE_MODE_READ))
                 goto out_put_task;
 
-        ns_dentry = proc_ns_get_dentry(sb, task, ei->ns_ops);
-        if (IS_ERR(ns_dentry)) {
-                error = ERR_CAST(ns_dentry);
+        ns_path.dentry = proc_ns_get_dentry(sb, task, ei->ns_ops);
+        if (IS_ERR(ns_path.dentry)) {
+                error = ERR_CAST(ns_path.dentry);
                 goto out_put_task;
         }
 
-        dput(nd->path.dentry);
-        nd->path.dentry = ns_dentry;
+        ns_path.mnt = mntget(nd->path.mnt);
+        nd_jump_link(nd, &ns_path);
         error = NULL;
 
 out_put_task: