diff options
| author | Tejun Heo <tj@kernel.org> | 2013-12-11 16:02:56 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-17 08:59:15 -0800 |
| commit | d0ae3d4347ee025cf23b850d484fe8593f7dd0f2 (patch) | |
| tree | 5d6e4464ab25022c840733b17be5d3480b1dea84 /fs/kernfs | |
| parent | bb8b9d095c5c56cce99576cfef0cf9b989f7120d (diff) | |
| download | linux-d0ae3d4347ee025cf23b850d484fe8593f7dd0f2.tar.gz | |
kernfs: add REMOVED check to create and rename paths
kernfs currently assumes that the caller doesn't try to create a new node under a removed parent, rename a removed node, or move a node under a removed node. While this works fine for sysfs, it'd be nice to have protection against such cases especially given that kernfs is planned to add support for mkdir, rmdir and rename requsts from userland which may make race conditions more likely. This patch updates create and rename paths to check REMOVED and fail the operation with -ENOENT if performed on or towards removed nodes. Note that remove path already has such check. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/kernfs')
| -rw-r--r-- | fs/kernfs/dir.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index e55bb02f15a4..ba5f372a226d 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -430,6 +430,9 @@ int kernfs_add_one(struct kernfs_addrm_cxt *acxt, struct kernfs_node *kn, if (kernfs_type(parent) != KERNFS_DIR) return -EINVAL; + if (parent->flags & KERNFS_REMOVED) + return -ENOENT; + kn->hash = kernfs_name_hash(kn->name, kn->ns); kn->parent = parent; kernfs_get(parent); @@ -863,6 +866,10 @@ int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent, mutex_lock(&kernfs_mutex); + error = -ENOENT; + if ((kn->flags | new_parent->flags) & KERNFS_REMOVED) + goto out; + error = 0; if ((kn->parent == new_parent) && (kn->ns == new_ns) && (strcmp(kn->name, new_name) == 0)) |