nuttx/fs/vfs/fs_rmdir.c
Abhishek Mishra 08afc5f2cf fs: enforce path search and unify inode permission helpers
Require X_OK on path ancestors and mountpoint gates via
inode_checkpathperm(), and use inode_checkperm() for inode mode checks.
inode_checkpathperm() takes the inode tree read lock (or INODE_CHECK_LOCKED
when the caller already holds it) and can fold a non-zero amode check onto
the target inode in the same call.

When CONFIG_FS_PERMISSION is disabled, inode_checkperm/inode_checkpathperm
are empty macros returning 0 so there is no stub .text cost.

Skip mountpoint R/W open-mode checks in inode_checkopenperm(); keep
traversal separate from open.  Add an optional mountpt_operations.permission
hook (tmpfs when CONFIG_FS_PERMISSION) for in-volume DAC without making the
VFS mount-crossing path depend on it.

Signed-off-by: Abhishek Mishra <mishra.abhishek2808@gmail.com>
2026-08-02 18:48:40 -03:00

185 lines
4.7 KiB
C

/****************************************************************************
* fs/vfs/fs_rmdir.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdbool.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/fs/fs.h>
#include "inode/inode.h"
#include "vfs.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#undef FS_HAVE_RMDIR
#if !defined(CONFIG_DISABLE_MOUNTPOINT) || !defined(CONFIG_DISABLE_PSEUDOFS_OPERATIONS)
# define FS_HAVE_RMDIR 1
#endif
#ifdef FS_HAVE_RMDIR
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: rmdir
*
* Description: Remove a file managed a mountpoint
*
****************************************************************************/
int rmdir(FAR const char *pathname)
{
struct inode_search_s desc;
FAR struct inode *inode;
int errcode;
int ret;
/* Get an inode for the directory (or for the mountpoint containing the
* directory). inode_find() automatically increments the reference count
* on the inode if one is found.
*/
SETUP_SEARCH(&desc, pathname, true);
ret = inode_find(&desc);
if (ret < 0)
{
/* There is no inode that includes in this path */
errcode = -ret;
goto errout_with_search;
}
/* Get the search results */
inode = desc.node;
DEBUGASSERT(inode != NULL);
#ifndef CONFIG_DISABLE_MOUNTPOINT
/* Check if the inode is a valid mountpoint. */
if (INODE_IS_MOUNTPT(inode) && inode->u.i_mops)
{
ret = inode_checkpathperm(inode, 0, 0);
if (ret < 0)
{
errcode = -ret;
goto errout_with_inode;
}
/* Perform the rmdir operation using the relative path
* from the mountpoint.
*/
if (inode->u.i_mops->rmdir)
{
ret = inode->u.i_mops->rmdir(inode, desc.relpath);
if (ret < 0)
{
errcode = -ret;
goto errout_with_inode;
}
}
else
{
errcode = ENOSYS;
goto errout_with_inode;
}
}
else
#endif
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
/* If this is a "dangling" pseudo-directory node (i.e., it has no
* operations) then rmdir should remove the node.
*/
if (!inode->u.i_ops)
{
/* If the directory inode has children, however, then it cannot be
* removed.
*/
if (inode->i_child)
{
errcode = ENOTEMPTY;
goto errout_with_inode;
}
/* Remove the inode. NOTE: Because we hold a reference count on the
* inode, it will not be deleted now. But probably when
* inode_release() is called below. inode_remove should return
* -EBUSY to indicate that the inode was not deleted now.
*/
inode_lock();
ret = inode_remove(pathname);
inode_unlock();
if (ret < 0 && ret != -EBUSY)
{
errcode = -ret;
goto errout_with_inode;
}
}
else
{
errcode = ENOTDIR;
goto errout_with_inode;
}
#else
{
errcode = ENXIO;
goto errout_with_inode;
}
#endif
/* Successfully removed the directory */
inode_release(inode);
RELEASE_SEARCH(&desc);
#ifdef CONFIG_FS_NOTIFY
notify_unlink(pathname);
#endif
return OK;
errout_with_inode:
inode_release(inode);
errout_with_search:
RELEASE_SEARCH(&desc);
set_errno(errcode);
return ERROR;
}
#endif /* FS_HAVE_RMDIR */