diff options
| -rw-r--r-- | fs/namespace.c | 53 |
1 files changed, 25 insertions, 28 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 87d2d82010bb..1bf302d0478b 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1205,32 +1205,32 @@ static int attach_recursive_mnt(struct vfsmount *source_mnt, return 0; } -static int graft_tree(struct vfsmount *mnt, struct nameidata *nd) +static int graft_tree(struct vfsmount *mnt, struct path *path) { int err; if (mnt->mnt_sb->s_flags & MS_NOUSER) return -EINVAL; - if (S_ISDIR(nd->path.dentry->d_inode->i_mode) != + if (S_ISDIR(path->dentry->d_inode->i_mode) != S_ISDIR(mnt->mnt_root->d_inode->i_mode)) return -ENOTDIR; err = -ENOENT; - mutex_lock(&nd->path.dentry->d_inode->i_mutex); - if (IS_DEADDIR(nd->path.dentry->d_inode)) + mutex_lock(&path->dentry->d_inode->i_mutex); + if (IS_DEADDIR(path->dentry->d_inode)) goto out_unlock; - err = security_sb_check_sb(mnt, &nd->path); + err = security_sb_check_sb(mnt, path); if (err) goto out_unlock; err = -ENOENT; - if (IS_ROOT(nd->path.dentry) || !d_unhashed(nd->path.dentry)) - err = attach_recursive_mnt(mnt, &nd->path, NULL); + if (IS_ROOT(path->dentry) || !d_unhashed(path->dentry)) + err = attach_recursive_mnt(mnt, path, NULL); out_unlock: - mutex_unlock(&nd->path.dentry->d_inode->i_mutex); + mutex_unlock(&path->dentry->d_inode->i_mutex); if (!err) - security_sb_post_addmount(mnt, &nd->path); + security_sb_post_addmount(mnt, path); return err; } @@ -1294,7 +1294,7 @@ static noinline int do_loopback(struct nameidata *nd, char *old_name, if (!mnt) goto out; - err = graft_tree(mnt, nd); + err = graft_tree(mnt, &nd->path); if (err) { LIST_HEAD(umount_list); spin_lock(&vfsmount_lock); @@ -1501,7 +1501,7 @@ int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd, goto unlock; newmnt->mnt_flags = mnt_flags; - if ((err = graft_tree(newmnt, nd))) + if ((err = graft_tree(newmnt, &nd->path))) goto unlock; if (fslist) /* add to the specified expiration list */ @@ -1987,15 +1987,13 @@ asmlinkage long sys_pivot_root(const char __user * new_root, const char __user * put_old) { struct vfsmount *tmp; - struct nameidata new_nd, old_nd, user_nd; - struct path parent_path, root_parent; + struct nameidata new_nd, old_nd; + struct path parent_path, root_parent, root; int error; if (!capable(CAP_SYS_ADMIN)) return -EPERM; - lock_kernel(); - error = __user_walk(new_root, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &new_nd); if (error) @@ -2015,7 +2013,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root, } read_lock(¤t->fs->lock); - user_nd.path = current->fs->root; + root = current->fs->root; path_get(¤t->fs->root); read_unlock(¤t->fs->lock); down_write(&namespace_sem); @@ -2023,9 +2021,9 @@ asmlinkage long sys_pivot_root(const char __user * new_root, error = -EINVAL; if (IS_MNT_SHARED(old_nd.path.mnt) || IS_MNT_SHARED(new_nd.path.mnt->mnt_parent) || - IS_MNT_SHARED(user_nd.path.mnt->mnt_parent)) + IS_MNT_SHARED(root.mnt->mnt_parent)) goto out2; - if (!check_mnt(user_nd.path.mnt)) + if (!check_mnt(root.mnt)) goto out2; error = -ENOENT; if (IS_DEADDIR(new_nd.path.dentry->d_inode)) @@ -2035,13 +2033,13 @@ asmlinkage long sys_pivot_root(const char __user * new_root, if (d_unhashed(old_nd.path.dentry) && !IS_ROOT(old_nd.path.dentry)) goto out2; error = -EBUSY; - if (new_nd.path.mnt == user_nd.path.mnt || - old_nd.path.mnt == user_nd.path.mnt) + if (new_nd.path.mnt == root.mnt || + old_nd.path.mnt == root.mnt) goto out2; /* loop, on the same file system */ error = -EINVAL; - if (user_nd.path.mnt->mnt_root != user_nd.path.dentry) + if (root.mnt->mnt_root != root.dentry) goto out2; /* not a mountpoint */ - if (user_nd.path.mnt->mnt_parent == user_nd.path.mnt) + if (root.mnt->mnt_parent == root.mnt) goto out2; /* not attached */ if (new_nd.path.mnt->mnt_root != new_nd.path.dentry) goto out2; /* not a mountpoint */ @@ -2063,27 +2061,26 @@ asmlinkage long sys_pivot_root(const char __user * new_root, } else if (!is_subdir(old_nd.path.dentry, new_nd.path.dentry)) goto out3; detach_mnt(new_nd.path.mnt, &parent_path); - detach_mnt(user_nd.path.mnt, &root_parent); + detach_mnt(root.mnt, &root_parent); /* mount old root on put_old */ - attach_mnt(user_nd.path.mnt, &old_nd.path); + attach_mnt(root.mnt, &old_nd.path); /* mount new_root on / */ attach_mnt(new_nd.path.mnt, &root_parent); touch_mnt_namespace(current->nsproxy->mnt_ns); spin_unlock(&vfsmount_lock); - chroot_fs_refs(&user_nd.path, &new_nd.path); - security_sb_post_pivotroot(&user_nd.path, &new_nd.path); + chroot_fs_refs(&root, &new_nd.path); + security_sb_post_pivotroot(&root, &new_nd.path); error = 0; path_put(&root_parent); path_put(&parent_path); out2: mutex_unlock(&old_nd.path.dentry->d_inode->i_mutex); up_write(&namespace_sem); - path_put(&user_nd.path); + path_put(&root); path_put(&old_nd.path); out1: path_put(&new_nd.path); out0: - unlock_kernel(); return error; out3: spin_unlock(&vfsmount_lock); |