don't drop newmnt on error in do_add_mount()
That gets rid of the kludge in finish_automount() - we need
to keep refcount on the vfsmount as-is until we evict it from
expiry list.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namespace.c b/fs/namespace.c
index bec51e4e..31aefc8 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1880,6 +1880,7 @@
int mnt_flags, char *name, void *data)
{
struct vfsmount *mnt;
+ int err;
if (!type)
return -EINVAL;
@@ -1892,7 +1893,10 @@
if (IS_ERR(mnt))
return PTR_ERR(mnt);
- return do_add_mount(mnt, path, mnt_flags);
+ err = do_add_mount(mnt, path, mnt_flags);
+ if (err)
+ mntput(mnt);
+ return err;
}
int finish_automount(struct vfsmount *m, struct path *path)
@@ -1911,26 +1915,17 @@
return -ELOOP;
}
- /* We need to add the mountpoint to the parent. The filesystem may
- * have placed it on an expiry list, and so we need to make sure it
- * won't be expired under us if do_add_mount() fails (do_add_mount()
- * will eat a reference unconditionally).
- */
- mntget(m);
err = do_add_mount(m, path, path->mnt->mnt_flags | MNT_SHRINKABLE);
if (err) {
mnt_clear_expiry(m);
mntput(m);
mntput(m);
- } else {
- mntput(m);
}
return err;
}
/*
* add a mount into a namespace's mount tree
- * - this unconditionally eats one of the caller's references to newmnt.
*/
int do_add_mount(struct vfsmount *newmnt, struct path *path, int mnt_flags)
{
@@ -1967,7 +1962,6 @@
unlock:
up_write(&namespace_sem);
- mntput(newmnt);
return err;
}