[PATCH] fs/namespace.c:dup_namespace(): fix a use after free

The Coverity checker spotted the following bug in dup_namespace():

<--  snip  -->

        if (!new_ns->root) {
                up_write(&namespace_sem);
                kfree(new_ns);
                goto out;
        }
...
out:
        return new_ns;

<--  snip  -->

Callers expect a non-NULL result to not be freed.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 058a44865beb..39c81a8d6316 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1338,7 +1338,7 @@ struct namespace *dup_namespace(struct task_struct *tsk, struct fs_struct *fs)
 
         new_ns = kmalloc(sizeof(struct namespace), GFP_KERNEL);
         if (!new_ns)
-                goto out;
+                return NULL;
 
         atomic_set(&new_ns->count, 1);
         INIT_LIST_HEAD(&new_ns->list);
@@ -1352,7 +1352,7 @@ struct namespace *dup_namespace(struct task_struct *tsk, struct fs_struct *fs)
         if (!new_ns->root) {
                 up_write(&namespace_sem);
                 kfree(new_ns);
-                goto out;
+                return NULL;
         }
         spin_lock(&vfsmount_lock);
         list_add_tail(&new_ns->list, &new_ns->root->mnt_list);
@@ -1393,7 +1393,6 @@ struct namespace *dup_namespace(struct task_struct *tsk, struct fs_struct *fs)
         if (altrootmnt)
                 mntput(altrootmnt);
 
-out:
         return new_ns;
 }