linux/kernel/audit_fsnotify.c
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00

206 lines
5.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* audit_fsnotify.c -- tracking inodes
*
* Copyright 2003-2009,2014-2015 Red Hat, Inc.
* Copyright 2005 Hewlett-Packard Development Company, L.P.
* Copyright 2005 IBM Corporation
*/
#include <linux/kernel.h>
#include <linux/audit.h>
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/fs.h>
#include <linux/fsnotify_backend.h>
#include <linux/namei.h>
#include <linux/netlink.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/security.h>
#include "audit.h"
/*
* this mark lives on the parent directory of the inode in question.
* but dev, ino, and path are about the child
*/
struct audit_fsnotify_mark {
dev_t dev; /* associated superblock device */
unsigned long ino; /* associated inode number */
char *path; /* insertion path */
struct fsnotify_mark mark; /* fsnotify mark on the inode */
struct audit_krule *rule;
};
/* fsnotify handle. */
static struct fsnotify_group *audit_fsnotify_group;
/* fsnotify events we care about. */
#define AUDIT_FS_EVENTS (FS_MOVE | FS_CREATE | FS_DELETE | FS_DELETE_SELF |\
FS_MOVE_SELF | FS_EVENT_ON_CHILD)
static void audit_fsnotify_mark_free(struct audit_fsnotify_mark *audit_mark)
{
kfree(audit_mark->path);
kfree(audit_mark);
}
static void audit_fsnotify_free_mark(struct fsnotify_mark *mark)
{
struct audit_fsnotify_mark *audit_mark;
audit_mark = container_of(mark, struct audit_fsnotify_mark, mark);
audit_fsnotify_mark_free(audit_mark);
}
char *audit_mark_path(struct audit_fsnotify_mark *mark)
{
return mark->path;
}
int audit_mark_compare(struct audit_fsnotify_mark *mark, unsigned long ino, dev_t dev)
{
if (mark->ino == AUDIT_INO_UNSET)
return 0;
return (mark->ino == ino) && (mark->dev == dev);
}
static void audit_update_mark(struct audit_fsnotify_mark *audit_mark,
const struct inode *inode)
{
audit_mark->dev = inode ? inode->i_sb->s_dev : AUDIT_DEV_UNSET;
audit_mark->ino = inode ? inode->i_ino : AUDIT_INO_UNSET;
}
struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule, char *pathname, int len)
{
struct audit_fsnotify_mark *audit_mark;
struct path path;
struct dentry *dentry;
struct inode *inode;
int ret;
if (pathname[0] != '/' || pathname[len-1] == '/')
return ERR_PTR(-EINVAL);
dentry = kern_path_locked(pathname, &path);
if (IS_ERR(dentry))
return (void *)dentry; /* returning an error */
inode = path.dentry->d_inode;
inode_unlock(inode);
audit_mark = kzalloc(sizeof(*audit_mark), GFP_KERNEL);
if (unlikely(!audit_mark)) {
audit_mark = ERR_PTR(-ENOMEM);
goto out;
}
fsnotify_init_mark(&audit_mark->mark, audit_fsnotify_group);
audit_mark->mark.mask = AUDIT_FS_EVENTS;
audit_mark->path = pathname;
audit_update_mark(audit_mark, dentry->d_inode);
audit_mark->rule = krule;
ret = fsnotify_add_inode_mark(&audit_mark->mark, inode, true);
if (ret < 0) {
fsnotify_put_mark(&audit_mark->mark);
audit_mark = ERR_PTR(ret);
}
out:
dput(dentry);
path_put(&path);
return audit_mark;
}
static void audit_mark_log_rule_change(struct audit_fsnotify_mark *audit_mark, char *op)
{
struct audit_buffer *ab;
struct audit_krule *rule = audit_mark->rule;
if (!audit_enabled)
return;
ab = audit_log_start(audit_context(), GFP_NOFS, AUDIT_CONFIG_CHANGE);
if (unlikely(!ab))
return;
audit_log_session_info(ab);
audit_log_format(ab, " op=%s path=", op);
audit_log_untrustedstring(ab, audit_mark->path);
audit_log_key(ab, rule->filterkey);
audit_log_format(ab, " list=%d res=1", rule->listnr);
audit_log_end(ab);
}
void audit_remove_mark(struct audit_fsnotify_mark *audit_mark)
{
fsnotify_destroy_mark(&audit_mark->mark, audit_fsnotify_group);
fsnotify_put_mark(&audit_mark->mark);
}
void audit_remove_mark_rule(struct audit_krule *krule)
{
struct audit_fsnotify_mark *mark = krule->exe;
audit_remove_mark(mark);
}
static void audit_autoremove_mark_rule(struct audit_fsnotify_mark *audit_mark)
{
struct audit_krule *rule = audit_mark->rule;
struct audit_entry *entry = container_of(rule, struct audit_entry, rule);
audit_mark_log_rule_change(audit_mark, "autoremove_rule");
audit_del_rule(entry);
}
/* Update mark data in audit rules based on fsnotify events. */
static int audit_mark_handle_event(struct fsnotify_group *group,
struct inode *to_tell,
u32 mask, const void *data, int data_type,
const struct qstr *dname, u32 cookie,
struct fsnotify_iter_info *iter_info)
{
struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info);
struct audit_fsnotify_mark *audit_mark;
const struct inode *inode = NULL;
audit_mark = container_of(inode_mark, struct audit_fsnotify_mark, mark);
BUG_ON(group != audit_fsnotify_group);
switch (data_type) {
case (FSNOTIFY_EVENT_PATH):
inode = ((const struct path *)data)->dentry->d_inode;
break;
case (FSNOTIFY_EVENT_INODE):
inode = (const struct inode *)data;
break;
default:
BUG();
return 0;
}
if (mask & (FS_CREATE|FS_MOVED_TO|FS_DELETE|FS_MOVED_FROM)) {
if (audit_compare_dname_path(dname, audit_mark->path, AUDIT_NAME_FULL))
return 0;
audit_update_mark(audit_mark, inode);
} else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF))
audit_autoremove_mark_rule(audit_mark);
return 0;
}
static const struct fsnotify_ops audit_mark_fsnotify_ops = {
.handle_event = audit_mark_handle_event,
.free_mark = audit_fsnotify_free_mark,
};
static int __init audit_fsnotify_init(void)
{
audit_fsnotify_group = fsnotify_alloc_group(&audit_mark_fsnotify_ops);
if (IS_ERR(audit_fsnotify_group)) {
audit_fsnotify_group = NULL;
audit_panic("cannot create audit fsnotify group");
}
return 0;
}
device_initcall(audit_fsnotify_init);