mirror of
https://github.com/torvalds/linux.git
synced 2024-11-21 19:46:16 +00:00
33be0cfa5b
A "nosymfollow" flag was added in commit
dab741e0e0
("Add a "nosymfollow" mount option.")
While we don't need to implement any special logic on
the AppArmor kernel side to handle it, we should provide
user with a correct list of mount flags in audit logs.
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
774 lines
20 KiB
C
774 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* AppArmor security module
|
|
*
|
|
* This file contains AppArmor mediation of files
|
|
*
|
|
* Copyright (C) 1998-2008 Novell/SUSE
|
|
* Copyright 2009-2017 Canonical Ltd.
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/mount.h>
|
|
#include <linux/namei.h>
|
|
#include <uapi/linux/mount.h>
|
|
|
|
#include "include/apparmor.h"
|
|
#include "include/audit.h"
|
|
#include "include/cred.h"
|
|
#include "include/domain.h"
|
|
#include "include/file.h"
|
|
#include "include/match.h"
|
|
#include "include/mount.h"
|
|
#include "include/path.h"
|
|
#include "include/policy.h"
|
|
|
|
|
|
static void audit_mnt_flags(struct audit_buffer *ab, unsigned long flags)
|
|
{
|
|
if (flags & MS_RDONLY)
|
|
audit_log_format(ab, "ro");
|
|
else
|
|
audit_log_format(ab, "rw");
|
|
if (flags & MS_NOSUID)
|
|
audit_log_format(ab, ", nosuid");
|
|
if (flags & MS_NODEV)
|
|
audit_log_format(ab, ", nodev");
|
|
if (flags & MS_NOEXEC)
|
|
audit_log_format(ab, ", noexec");
|
|
if (flags & MS_SYNCHRONOUS)
|
|
audit_log_format(ab, ", sync");
|
|
if (flags & MS_REMOUNT)
|
|
audit_log_format(ab, ", remount");
|
|
if (flags & MS_MANDLOCK)
|
|
audit_log_format(ab, ", mand");
|
|
if (flags & MS_DIRSYNC)
|
|
audit_log_format(ab, ", dirsync");
|
|
if (flags & MS_NOSYMFOLLOW)
|
|
audit_log_format(ab, ", nosymfollow");
|
|
if (flags & MS_NOATIME)
|
|
audit_log_format(ab, ", noatime");
|
|
if (flags & MS_NODIRATIME)
|
|
audit_log_format(ab, ", nodiratime");
|
|
if (flags & MS_BIND)
|
|
audit_log_format(ab, flags & MS_REC ? ", rbind" : ", bind");
|
|
if (flags & MS_MOVE)
|
|
audit_log_format(ab, ", move");
|
|
if (flags & MS_SILENT)
|
|
audit_log_format(ab, ", silent");
|
|
if (flags & MS_POSIXACL)
|
|
audit_log_format(ab, ", acl");
|
|
if (flags & MS_UNBINDABLE)
|
|
audit_log_format(ab, flags & MS_REC ? ", runbindable" :
|
|
", unbindable");
|
|
if (flags & MS_PRIVATE)
|
|
audit_log_format(ab, flags & MS_REC ? ", rprivate" :
|
|
", private");
|
|
if (flags & MS_SLAVE)
|
|
audit_log_format(ab, flags & MS_REC ? ", rslave" :
|
|
", slave");
|
|
if (flags & MS_SHARED)
|
|
audit_log_format(ab, flags & MS_REC ? ", rshared" :
|
|
", shared");
|
|
if (flags & MS_RELATIME)
|
|
audit_log_format(ab, ", relatime");
|
|
if (flags & MS_I_VERSION)
|
|
audit_log_format(ab, ", iversion");
|
|
if (flags & MS_STRICTATIME)
|
|
audit_log_format(ab, ", strictatime");
|
|
if (flags & MS_NOUSER)
|
|
audit_log_format(ab, ", nouser");
|
|
}
|
|
|
|
/**
|
|
* audit_cb - call back for mount specific audit fields
|
|
* @ab: audit_buffer (NOT NULL)
|
|
* @va: audit struct to audit values of (NOT NULL)
|
|
*/
|
|
static void audit_cb(struct audit_buffer *ab, void *va)
|
|
{
|
|
struct common_audit_data *sa = va;
|
|
struct apparmor_audit_data *ad = aad(sa);
|
|
|
|
if (ad->mnt.type) {
|
|
audit_log_format(ab, " fstype=");
|
|
audit_log_untrustedstring(ab, ad->mnt.type);
|
|
}
|
|
if (ad->mnt.src_name) {
|
|
audit_log_format(ab, " srcname=");
|
|
audit_log_untrustedstring(ab, ad->mnt.src_name);
|
|
}
|
|
if (ad->mnt.trans) {
|
|
audit_log_format(ab, " trans=");
|
|
audit_log_untrustedstring(ab, ad->mnt.trans);
|
|
}
|
|
if (ad->mnt.flags) {
|
|
audit_log_format(ab, " flags=\"");
|
|
audit_mnt_flags(ab, ad->mnt.flags);
|
|
audit_log_format(ab, "\"");
|
|
}
|
|
if (ad->mnt.data) {
|
|
audit_log_format(ab, " options=");
|
|
audit_log_untrustedstring(ab, ad->mnt.data);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* audit_mount - handle the auditing of mount operations
|
|
* @subj_cred: cred of the subject
|
|
* @profile: the profile being enforced (NOT NULL)
|
|
* @op: operation being mediated (NOT NULL)
|
|
* @name: name of object being mediated (MAYBE NULL)
|
|
* @src_name: src_name of object being mediated (MAYBE_NULL)
|
|
* @type: type of filesystem (MAYBE_NULL)
|
|
* @trans: name of trans (MAYBE NULL)
|
|
* @flags: filesystem independent mount flags
|
|
* @data: filesystem mount flags
|
|
* @request: permissions requested
|
|
* @perms: the permissions computed for the request (NOT NULL)
|
|
* @info: extra information message (MAYBE NULL)
|
|
* @error: 0 if operation allowed else failure error code
|
|
*
|
|
* Returns: %0 or error on failure
|
|
*/
|
|
static int audit_mount(const struct cred *subj_cred,
|
|
struct aa_profile *profile, const char *op,
|
|
const char *name, const char *src_name,
|
|
const char *type, const char *trans,
|
|
unsigned long flags, const void *data, u32 request,
|
|
struct aa_perms *perms, const char *info, int error)
|
|
{
|
|
int audit_type = AUDIT_APPARMOR_AUTO;
|
|
DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_MOUNT, op);
|
|
|
|
if (likely(!error)) {
|
|
u32 mask = perms->audit;
|
|
|
|
if (unlikely(AUDIT_MODE(profile) == AUDIT_ALL))
|
|
mask = 0xffff;
|
|
|
|
/* mask off perms that are not being force audited */
|
|
request &= mask;
|
|
|
|
if (likely(!request))
|
|
return 0;
|
|
audit_type = AUDIT_APPARMOR_AUDIT;
|
|
} else {
|
|
/* only report permissions that were denied */
|
|
request = request & ~perms->allow;
|
|
|
|
if (request & perms->kill)
|
|
audit_type = AUDIT_APPARMOR_KILL;
|
|
|
|
/* quiet known rejects, assumes quiet and kill do not overlap */
|
|
if ((request & perms->quiet) &&
|
|
AUDIT_MODE(profile) != AUDIT_NOQUIET &&
|
|
AUDIT_MODE(profile) != AUDIT_ALL)
|
|
request &= ~perms->quiet;
|
|
|
|
if (!request)
|
|
return error;
|
|
}
|
|
|
|
ad.subj_cred = subj_cred;
|
|
ad.name = name;
|
|
ad.mnt.src_name = src_name;
|
|
ad.mnt.type = type;
|
|
ad.mnt.trans = trans;
|
|
ad.mnt.flags = flags;
|
|
if (data && (perms->audit & AA_AUDIT_DATA))
|
|
ad.mnt.data = data;
|
|
ad.info = info;
|
|
ad.error = error;
|
|
|
|
return aa_audit(audit_type, profile, &ad, audit_cb);
|
|
}
|
|
|
|
/**
|
|
* match_mnt_flags - Do an ordered match on mount flags
|
|
* @dfa: dfa to match against
|
|
* @state: state to start in
|
|
* @flags: mount flags to match against
|
|
*
|
|
* Mount flags are encoded as an ordered match. This is done instead of
|
|
* checking against a simple bitmask, to allow for logical operations
|
|
* on the flags.
|
|
*
|
|
* Returns: next state after flags match
|
|
*/
|
|
static aa_state_t match_mnt_flags(struct aa_dfa *dfa, aa_state_t state,
|
|
unsigned long flags)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i <= 31 ; ++i) {
|
|
if ((1 << i) & flags)
|
|
state = aa_dfa_next(dfa, state, i + 1);
|
|
}
|
|
|
|
return state;
|
|
}
|
|
|
|
static const char * const mnt_info_table[] = {
|
|
"match succeeded",
|
|
"failed mntpnt match",
|
|
"failed srcname match",
|
|
"failed type match",
|
|
"failed flags match",
|
|
"failed data match",
|
|
"failed perms check"
|
|
};
|
|
|
|
/*
|
|
* Returns 0 on success else element that match failed in, this is the
|
|
* index into the mnt_info_table above
|
|
*/
|
|
static int do_match_mnt(struct aa_policydb *policy, aa_state_t start,
|
|
const char *mntpnt, const char *devname,
|
|
const char *type, unsigned long flags,
|
|
void *data, bool binary, struct aa_perms *perms)
|
|
{
|
|
aa_state_t state;
|
|
|
|
AA_BUG(!policy);
|
|
AA_BUG(!policy->dfa);
|
|
AA_BUG(!policy->perms);
|
|
AA_BUG(!perms);
|
|
|
|
state = aa_dfa_match(policy->dfa, start, mntpnt);
|
|
state = aa_dfa_null_transition(policy->dfa, state);
|
|
if (!state)
|
|
return 1;
|
|
|
|
if (devname)
|
|
state = aa_dfa_match(policy->dfa, state, devname);
|
|
state = aa_dfa_null_transition(policy->dfa, state);
|
|
if (!state)
|
|
return 2;
|
|
|
|
if (type)
|
|
state = aa_dfa_match(policy->dfa, state, type);
|
|
state = aa_dfa_null_transition(policy->dfa, state);
|
|
if (!state)
|
|
return 3;
|
|
|
|
state = match_mnt_flags(policy->dfa, state, flags);
|
|
if (!state)
|
|
return 4;
|
|
*perms = *aa_lookup_perms(policy, state);
|
|
if (perms->allow & AA_MAY_MOUNT)
|
|
return 0;
|
|
|
|
/* only match data if not binary and the DFA flags data is expected */
|
|
if (data && !binary && (perms->allow & AA_MNT_CONT_MATCH)) {
|
|
state = aa_dfa_null_transition(policy->dfa, state);
|
|
if (!state)
|
|
return 4;
|
|
|
|
state = aa_dfa_match(policy->dfa, state, data);
|
|
if (!state)
|
|
return 5;
|
|
*perms = *aa_lookup_perms(policy, state);
|
|
if (perms->allow & AA_MAY_MOUNT)
|
|
return 0;
|
|
}
|
|
|
|
/* failed at perms check, don't confuse with flags match */
|
|
return 6;
|
|
}
|
|
|
|
|
|
static int path_flags(struct aa_profile *profile, const struct path *path)
|
|
{
|
|
AA_BUG(!profile);
|
|
AA_BUG(!path);
|
|
|
|
return profile->path_flags |
|
|
(S_ISDIR(path->dentry->d_inode->i_mode) ? PATH_IS_DIR : 0);
|
|
}
|
|
|
|
/**
|
|
* match_mnt_path_str - handle path matching for mount
|
|
* @subj_cred: cred of confined subject
|
|
* @profile: the confining profile
|
|
* @mntpath: for the mntpnt (NOT NULL)
|
|
* @buffer: buffer to be used to lookup mntpath
|
|
* @devname: string for the devname/src_name (MAY BE NULL OR ERRPTR)
|
|
* @type: string for the dev type (MAYBE NULL)
|
|
* @flags: mount flags to match
|
|
* @data: fs mount data (MAYBE NULL)
|
|
* @binary: whether @data is binary
|
|
* @devinfo: error str if (IS_ERR(@devname))
|
|
*
|
|
* Returns: 0 on success else error
|
|
*/
|
|
static int match_mnt_path_str(const struct cred *subj_cred,
|
|
struct aa_profile *profile,
|
|
const struct path *mntpath, char *buffer,
|
|
const char *devname, const char *type,
|
|
unsigned long flags, void *data, bool binary,
|
|
const char *devinfo)
|
|
{
|
|
struct aa_perms perms = { };
|
|
const char *mntpnt = NULL, *info = NULL;
|
|
struct aa_ruleset *rules = list_first_entry(&profile->rules,
|
|
typeof(*rules), list);
|
|
int pos, error;
|
|
|
|
AA_BUG(!profile);
|
|
AA_BUG(!mntpath);
|
|
AA_BUG(!buffer);
|
|
|
|
if (!RULE_MEDIATES(rules, AA_CLASS_MOUNT))
|
|
return 0;
|
|
|
|
error = aa_path_name(mntpath, path_flags(profile, mntpath), buffer,
|
|
&mntpnt, &info, profile->disconnected);
|
|
if (error)
|
|
goto audit;
|
|
if (IS_ERR(devname)) {
|
|
error = PTR_ERR(devname);
|
|
devname = NULL;
|
|
info = devinfo;
|
|
goto audit;
|
|
}
|
|
|
|
error = -EACCES;
|
|
pos = do_match_mnt(rules->policy,
|
|
rules->policy->start[AA_CLASS_MOUNT],
|
|
mntpnt, devname, type, flags, data, binary, &perms);
|
|
if (pos) {
|
|
info = mnt_info_table[pos];
|
|
goto audit;
|
|
}
|
|
error = 0;
|
|
|
|
audit:
|
|
return audit_mount(subj_cred, profile, OP_MOUNT, mntpnt, devname,
|
|
type, NULL,
|
|
flags, data, AA_MAY_MOUNT, &perms, info, error);
|
|
}
|
|
|
|
/**
|
|
* match_mnt - handle path matching for mount
|
|
* @subj_cred: cred of the subject
|
|
* @profile: the confining profile
|
|
* @path: for the mntpnt (NOT NULL)
|
|
* @buffer: buffer to be used to lookup mntpath
|
|
* @devpath: path devname/src_name (MAYBE NULL)
|
|
* @devbuffer: buffer to be used to lookup devname/src_name
|
|
* @type: string for the dev type (MAYBE NULL)
|
|
* @flags: mount flags to match
|
|
* @data: fs mount data (MAYBE NULL)
|
|
* @binary: whether @data is binary
|
|
*
|
|
* Returns: 0 on success else error
|
|
*/
|
|
static int match_mnt(const struct cred *subj_cred,
|
|
struct aa_profile *profile, const struct path *path,
|
|
char *buffer, const struct path *devpath, char *devbuffer,
|
|
const char *type, unsigned long flags, void *data,
|
|
bool binary)
|
|
{
|
|
const char *devname = NULL, *info = NULL;
|
|
struct aa_ruleset *rules = list_first_entry(&profile->rules,
|
|
typeof(*rules), list);
|
|
int error = -EACCES;
|
|
|
|
AA_BUG(!profile);
|
|
AA_BUG(devpath && !devbuffer);
|
|
|
|
if (!RULE_MEDIATES(rules, AA_CLASS_MOUNT))
|
|
return 0;
|
|
|
|
if (devpath) {
|
|
error = aa_path_name(devpath, path_flags(profile, devpath),
|
|
devbuffer, &devname, &info,
|
|
profile->disconnected);
|
|
if (error)
|
|
devname = ERR_PTR(error);
|
|
}
|
|
|
|
return match_mnt_path_str(subj_cred, profile, path, buffer, devname,
|
|
type, flags, data, binary, info);
|
|
}
|
|
|
|
int aa_remount(const struct cred *subj_cred,
|
|
struct aa_label *label, const struct path *path,
|
|
unsigned long flags, void *data)
|
|
{
|
|
struct aa_profile *profile;
|
|
char *buffer = NULL;
|
|
bool binary;
|
|
int error;
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!path);
|
|
|
|
binary = path->dentry->d_sb->s_type->fs_flags & FS_BINARY_MOUNTDATA;
|
|
|
|
buffer = aa_get_buffer(false);
|
|
if (!buffer)
|
|
return -ENOMEM;
|
|
error = fn_for_each_confined(label, profile,
|
|
match_mnt(subj_cred, profile, path, buffer, NULL,
|
|
NULL, NULL,
|
|
flags, data, binary));
|
|
aa_put_buffer(buffer);
|
|
|
|
return error;
|
|
}
|
|
|
|
int aa_bind_mount(const struct cred *subj_cred,
|
|
struct aa_label *label, const struct path *path,
|
|
const char *dev_name, unsigned long flags)
|
|
{
|
|
struct aa_profile *profile;
|
|
char *buffer = NULL, *old_buffer = NULL;
|
|
struct path old_path;
|
|
int error;
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!path);
|
|
|
|
if (!dev_name || !*dev_name)
|
|
return -EINVAL;
|
|
|
|
flags &= MS_REC | MS_BIND;
|
|
|
|
error = kern_path(dev_name, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &old_path);
|
|
if (error)
|
|
return error;
|
|
|
|
buffer = aa_get_buffer(false);
|
|
old_buffer = aa_get_buffer(false);
|
|
error = -ENOMEM;
|
|
if (!buffer || !old_buffer)
|
|
goto out;
|
|
|
|
error = fn_for_each_confined(label, profile,
|
|
match_mnt(subj_cred, profile, path, buffer, &old_path,
|
|
old_buffer, NULL, flags, NULL, false));
|
|
out:
|
|
aa_put_buffer(buffer);
|
|
aa_put_buffer(old_buffer);
|
|
path_put(&old_path);
|
|
|
|
return error;
|
|
}
|
|
|
|
int aa_mount_change_type(const struct cred *subj_cred,
|
|
struct aa_label *label, const struct path *path,
|
|
unsigned long flags)
|
|
{
|
|
struct aa_profile *profile;
|
|
char *buffer = NULL;
|
|
int error;
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!path);
|
|
|
|
/* These are the flags allowed by do_change_type() */
|
|
flags &= (MS_REC | MS_SILENT | MS_SHARED | MS_PRIVATE | MS_SLAVE |
|
|
MS_UNBINDABLE);
|
|
|
|
buffer = aa_get_buffer(false);
|
|
if (!buffer)
|
|
return -ENOMEM;
|
|
error = fn_for_each_confined(label, profile,
|
|
match_mnt(subj_cred, profile, path, buffer, NULL,
|
|
NULL, NULL,
|
|
flags, NULL, false));
|
|
aa_put_buffer(buffer);
|
|
|
|
return error;
|
|
}
|
|
|
|
int aa_move_mount(const struct cred *subj_cred,
|
|
struct aa_label *label, const struct path *from_path,
|
|
const struct path *to_path)
|
|
{
|
|
struct aa_profile *profile;
|
|
char *to_buffer = NULL, *from_buffer = NULL;
|
|
int error;
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!from_path);
|
|
AA_BUG(!to_path);
|
|
|
|
to_buffer = aa_get_buffer(false);
|
|
from_buffer = aa_get_buffer(false);
|
|
error = -ENOMEM;
|
|
if (!to_buffer || !from_buffer)
|
|
goto out;
|
|
|
|
if (!our_mnt(from_path->mnt))
|
|
/* moving a mount detached from the namespace */
|
|
from_path = NULL;
|
|
error = fn_for_each_confined(label, profile,
|
|
match_mnt(subj_cred, profile, to_path, to_buffer,
|
|
from_path, from_buffer,
|
|
NULL, MS_MOVE, NULL, false));
|
|
out:
|
|
aa_put_buffer(to_buffer);
|
|
aa_put_buffer(from_buffer);
|
|
|
|
return error;
|
|
}
|
|
|
|
int aa_move_mount_old(const struct cred *subj_cred, struct aa_label *label,
|
|
const struct path *path, const char *orig_name)
|
|
{
|
|
struct path old_path;
|
|
int error;
|
|
|
|
if (!orig_name || !*orig_name)
|
|
return -EINVAL;
|
|
error = kern_path(orig_name, LOOKUP_FOLLOW, &old_path);
|
|
if (error)
|
|
return error;
|
|
|
|
error = aa_move_mount(subj_cred, label, &old_path, path);
|
|
path_put(&old_path);
|
|
|
|
return error;
|
|
}
|
|
|
|
int aa_new_mount(const struct cred *subj_cred, struct aa_label *label,
|
|
const char *dev_name, const struct path *path,
|
|
const char *type, unsigned long flags, void *data)
|
|
{
|
|
struct aa_profile *profile;
|
|
char *buffer = NULL, *dev_buffer = NULL;
|
|
bool binary = true;
|
|
int error;
|
|
int requires_dev = 0;
|
|
struct path tmp_path, *dev_path = NULL;
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!path);
|
|
|
|
if (type) {
|
|
struct file_system_type *fstype;
|
|
|
|
fstype = get_fs_type(type);
|
|
if (!fstype)
|
|
return -ENODEV;
|
|
binary = fstype->fs_flags & FS_BINARY_MOUNTDATA;
|
|
requires_dev = fstype->fs_flags & FS_REQUIRES_DEV;
|
|
put_filesystem(fstype);
|
|
|
|
if (requires_dev) {
|
|
if (!dev_name || !*dev_name)
|
|
return -ENOENT;
|
|
|
|
error = kern_path(dev_name, LOOKUP_FOLLOW, &tmp_path);
|
|
if (error)
|
|
return error;
|
|
dev_path = &tmp_path;
|
|
}
|
|
}
|
|
|
|
buffer = aa_get_buffer(false);
|
|
if (!buffer) {
|
|
error = -ENOMEM;
|
|
goto out;
|
|
}
|
|
if (dev_path) {
|
|
dev_buffer = aa_get_buffer(false);
|
|
if (!dev_buffer) {
|
|
error = -ENOMEM;
|
|
goto out;
|
|
}
|
|
error = fn_for_each_confined(label, profile,
|
|
match_mnt(subj_cred, profile, path, buffer,
|
|
dev_path, dev_buffer,
|
|
type, flags, data, binary));
|
|
} else {
|
|
error = fn_for_each_confined(label, profile,
|
|
match_mnt_path_str(subj_cred, profile, path,
|
|
buffer, dev_name,
|
|
type, flags, data, binary, NULL));
|
|
}
|
|
|
|
out:
|
|
aa_put_buffer(buffer);
|
|
aa_put_buffer(dev_buffer);
|
|
if (dev_path)
|
|
path_put(dev_path);
|
|
|
|
return error;
|
|
}
|
|
|
|
static int profile_umount(const struct cred *subj_cred,
|
|
struct aa_profile *profile, const struct path *path,
|
|
char *buffer)
|
|
{
|
|
struct aa_ruleset *rules = list_first_entry(&profile->rules,
|
|
typeof(*rules), list);
|
|
struct aa_perms perms = { };
|
|
const char *name = NULL, *info = NULL;
|
|
aa_state_t state;
|
|
int error;
|
|
|
|
AA_BUG(!profile);
|
|
AA_BUG(!path);
|
|
|
|
if (!RULE_MEDIATES(rules, AA_CLASS_MOUNT))
|
|
return 0;
|
|
|
|
error = aa_path_name(path, path_flags(profile, path), buffer, &name,
|
|
&info, profile->disconnected);
|
|
if (error)
|
|
goto audit;
|
|
|
|
state = aa_dfa_match(rules->policy->dfa,
|
|
rules->policy->start[AA_CLASS_MOUNT],
|
|
name);
|
|
perms = *aa_lookup_perms(rules->policy, state);
|
|
if (AA_MAY_UMOUNT & ~perms.allow)
|
|
error = -EACCES;
|
|
|
|
audit:
|
|
return audit_mount(subj_cred, profile, OP_UMOUNT, name, NULL, NULL,
|
|
NULL, 0, NULL,
|
|
AA_MAY_UMOUNT, &perms, info, error);
|
|
}
|
|
|
|
int aa_umount(const struct cred *subj_cred, struct aa_label *label,
|
|
struct vfsmount *mnt, int flags)
|
|
{
|
|
struct aa_profile *profile;
|
|
char *buffer = NULL;
|
|
int error;
|
|
struct path path = { .mnt = mnt, .dentry = mnt->mnt_root };
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!mnt);
|
|
|
|
buffer = aa_get_buffer(false);
|
|
if (!buffer)
|
|
return -ENOMEM;
|
|
|
|
error = fn_for_each_confined(label, profile,
|
|
profile_umount(subj_cred, profile, &path, buffer));
|
|
aa_put_buffer(buffer);
|
|
|
|
return error;
|
|
}
|
|
|
|
/* helper fn for transition on pivotroot
|
|
*
|
|
* Returns: label for transition or ERR_PTR. Does not return NULL
|
|
*/
|
|
static struct aa_label *build_pivotroot(const struct cred *subj_cred,
|
|
struct aa_profile *profile,
|
|
const struct path *new_path,
|
|
char *new_buffer,
|
|
const struct path *old_path,
|
|
char *old_buffer)
|
|
{
|
|
struct aa_ruleset *rules = list_first_entry(&profile->rules,
|
|
typeof(*rules), list);
|
|
const char *old_name, *new_name = NULL, *info = NULL;
|
|
const char *trans_name = NULL;
|
|
struct aa_perms perms = { };
|
|
aa_state_t state;
|
|
int error;
|
|
|
|
AA_BUG(!profile);
|
|
AA_BUG(!new_path);
|
|
AA_BUG(!old_path);
|
|
|
|
if (profile_unconfined(profile) ||
|
|
!RULE_MEDIATES(rules, AA_CLASS_MOUNT))
|
|
return aa_get_newest_label(&profile->label);
|
|
|
|
error = aa_path_name(old_path, path_flags(profile, old_path),
|
|
old_buffer, &old_name, &info,
|
|
profile->disconnected);
|
|
if (error)
|
|
goto audit;
|
|
error = aa_path_name(new_path, path_flags(profile, new_path),
|
|
new_buffer, &new_name, &info,
|
|
profile->disconnected);
|
|
if (error)
|
|
goto audit;
|
|
|
|
error = -EACCES;
|
|
state = aa_dfa_match(rules->policy->dfa,
|
|
rules->policy->start[AA_CLASS_MOUNT],
|
|
new_name);
|
|
state = aa_dfa_null_transition(rules->policy->dfa, state);
|
|
state = aa_dfa_match(rules->policy->dfa, state, old_name);
|
|
perms = *aa_lookup_perms(rules->policy, state);
|
|
|
|
if (AA_MAY_PIVOTROOT & perms.allow)
|
|
error = 0;
|
|
|
|
audit:
|
|
error = audit_mount(subj_cred, profile, OP_PIVOTROOT, new_name,
|
|
old_name,
|
|
NULL, trans_name, 0, NULL, AA_MAY_PIVOTROOT,
|
|
&perms, info, error);
|
|
if (error)
|
|
return ERR_PTR(error);
|
|
|
|
return aa_get_newest_label(&profile->label);
|
|
}
|
|
|
|
int aa_pivotroot(const struct cred *subj_cred, struct aa_label *label,
|
|
const struct path *old_path,
|
|
const struct path *new_path)
|
|
{
|
|
struct aa_profile *profile;
|
|
struct aa_label *target = NULL;
|
|
char *old_buffer = NULL, *new_buffer = NULL, *info = NULL;
|
|
int error;
|
|
|
|
AA_BUG(!label);
|
|
AA_BUG(!old_path);
|
|
AA_BUG(!new_path);
|
|
|
|
old_buffer = aa_get_buffer(false);
|
|
new_buffer = aa_get_buffer(false);
|
|
error = -ENOMEM;
|
|
if (!old_buffer || !new_buffer)
|
|
goto out;
|
|
target = fn_label_build(label, profile, GFP_KERNEL,
|
|
build_pivotroot(subj_cred, profile, new_path,
|
|
new_buffer,
|
|
old_path, old_buffer));
|
|
if (!target) {
|
|
info = "label build failed";
|
|
error = -ENOMEM;
|
|
goto fail;
|
|
} else if (!IS_ERR(target)) {
|
|
error = aa_replace_current_label(target);
|
|
if (error) {
|
|
/* TODO: audit target */
|
|
aa_put_label(target);
|
|
goto out;
|
|
}
|
|
aa_put_label(target);
|
|
} else
|
|
/* already audited error */
|
|
error = PTR_ERR(target);
|
|
out:
|
|
aa_put_buffer(old_buffer);
|
|
aa_put_buffer(new_buffer);
|
|
|
|
return error;
|
|
|
|
fail:
|
|
/* TODO: add back in auditing of new_name and old_name */
|
|
error = fn_for_each(label, profile,
|
|
audit_mount(subj_cred, profile, OP_PIVOTROOT,
|
|
NULL /*new_name */,
|
|
NULL /* old_name */,
|
|
NULL, NULL,
|
|
0, NULL, AA_MAY_PIVOTROOT, &nullperms, info,
|
|
error));
|
|
goto out;
|
|
}
|