mirror of
https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
synced 2024-11-01 10:33:27 +00:00
04fdc099f9
The pointer returned from tracehook_tracer_task() is only valid inside the rcu_read_lock. However the tracer pointer obtained is being passed to aa_may_ptrace outside of the rcu_read_lock critical section. Mover the aa_may_ptrace test into the rcu_read_lock critical section, to fix this. Kernels affected: 2.6.36 - 3.0 Reported-by: Oleg Nesterov <oleg@redhat.com> Cc: stable@kernel.org Signed-off-by: John Johansen <john.johansen@canonical.com>
823 lines
21 KiB
C
823 lines
21 KiB
C
/*
|
|
* AppArmor security module
|
|
*
|
|
* This file contains AppArmor policy attachment and domain transitions
|
|
*
|
|
* Copyright (C) 2002-2008 Novell/SUSE
|
|
* Copyright 2009-2010 Canonical Ltd.
|
|
*
|
|
* 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, version 2 of the
|
|
* License.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/fdtable.h>
|
|
#include <linux/file.h>
|
|
#include <linux/mount.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/tracehook.h>
|
|
#include <linux/personality.h>
|
|
|
|
#include "include/audit.h"
|
|
#include "include/apparmorfs.h"
|
|
#include "include/context.h"
|
|
#include "include/domain.h"
|
|
#include "include/file.h"
|
|
#include "include/ipc.h"
|
|
#include "include/match.h"
|
|
#include "include/path.h"
|
|
#include "include/policy.h"
|
|
|
|
/**
|
|
* aa_free_domain_entries - free entries in a domain table
|
|
* @domain: the domain table to free (MAYBE NULL)
|
|
*/
|
|
void aa_free_domain_entries(struct aa_domain *domain)
|
|
{
|
|
int i;
|
|
if (domain) {
|
|
if (!domain->table)
|
|
return;
|
|
|
|
for (i = 0; i < domain->size; i++)
|
|
kzfree(domain->table[i]);
|
|
kzfree(domain->table);
|
|
domain->table = NULL;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* may_change_ptraced_domain - check if can change profile on ptraced task
|
|
* @task: task we want to change profile of (NOT NULL)
|
|
* @to_profile: profile to change to (NOT NULL)
|
|
*
|
|
* Check if the task is ptraced and if so if the tracing task is allowed
|
|
* to trace the new domain
|
|
*
|
|
* Returns: %0 or error if change not allowed
|
|
*/
|
|
static int may_change_ptraced_domain(struct task_struct *task,
|
|
struct aa_profile *to_profile)
|
|
{
|
|
struct task_struct *tracer;
|
|
const struct cred *cred = NULL;
|
|
struct aa_profile *tracerp = NULL;
|
|
int error = 0;
|
|
|
|
rcu_read_lock();
|
|
tracer = tracehook_tracer_task(task);
|
|
if (tracer) {
|
|
/* released below */
|
|
cred = get_task_cred(tracer);
|
|
tracerp = aa_cred_profile(cred);
|
|
}
|
|
|
|
/* not ptraced */
|
|
if (!tracer || unconfined(tracerp))
|
|
goto out;
|
|
|
|
error = aa_may_ptrace(tracer, tracerp, to_profile, PTRACE_MODE_ATTACH);
|
|
|
|
out:
|
|
rcu_read_unlock();
|
|
if (cred)
|
|
put_cred(cred);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* change_profile_perms - find permissions for change_profile
|
|
* @profile: the current profile (NOT NULL)
|
|
* @ns: the namespace being switched to (NOT NULL)
|
|
* @name: the name of the profile to change to (NOT NULL)
|
|
* @request: requested perms
|
|
* @start: state to start matching in
|
|
*
|
|
* Returns: permission set
|
|
*/
|
|
static struct file_perms change_profile_perms(struct aa_profile *profile,
|
|
struct aa_namespace *ns,
|
|
const char *name, u32 request,
|
|
unsigned int start)
|
|
{
|
|
struct file_perms perms;
|
|
struct path_cond cond = { };
|
|
unsigned int state;
|
|
|
|
if (unconfined(profile)) {
|
|
perms.allow = AA_MAY_CHANGE_PROFILE | AA_MAY_ONEXEC;
|
|
perms.audit = perms.quiet = perms.kill = 0;
|
|
return perms;
|
|
} else if (!profile->file.dfa) {
|
|
return nullperms;
|
|
} else if ((ns == profile->ns)) {
|
|
/* try matching against rules with out namespace prepended */
|
|
aa_str_perms(profile->file.dfa, start, name, &cond, &perms);
|
|
if (COMBINED_PERM_MASK(perms) & request)
|
|
return perms;
|
|
}
|
|
|
|
/* try matching with namespace name and then profile */
|
|
state = aa_dfa_match(profile->file.dfa, start, ns->base.name);
|
|
state = aa_dfa_match_len(profile->file.dfa, state, ":", 1);
|
|
aa_str_perms(profile->file.dfa, state, name, &cond, &perms);
|
|
|
|
return perms;
|
|
}
|
|
|
|
/**
|
|
* __attach_match_ - find an attachment match
|
|
* @name - to match against (NOT NULL)
|
|
* @head - profile list to walk (NOT NULL)
|
|
*
|
|
* Do a linear search on the profiles in the list. There is a matching
|
|
* preference where an exact match is preferred over a name which uses
|
|
* expressions to match, and matching expressions with the greatest
|
|
* xmatch_len are preferred.
|
|
*
|
|
* Requires: @head not be shared or have appropriate locks held
|
|
*
|
|
* Returns: profile or NULL if no match found
|
|
*/
|
|
static struct aa_profile *__attach_match(const char *name,
|
|
struct list_head *head)
|
|
{
|
|
int len = 0;
|
|
struct aa_profile *profile, *candidate = NULL;
|
|
|
|
list_for_each_entry(profile, head, base.list) {
|
|
if (profile->flags & PFLAG_NULL)
|
|
continue;
|
|
if (profile->xmatch && profile->xmatch_len > len) {
|
|
unsigned int state = aa_dfa_match(profile->xmatch,
|
|
DFA_START, name);
|
|
u32 perm = dfa_user_allow(profile->xmatch, state);
|
|
/* any accepting state means a valid match. */
|
|
if (perm & MAY_EXEC) {
|
|
candidate = profile;
|
|
len = profile->xmatch_len;
|
|
}
|
|
} else if (!strcmp(profile->base.name, name))
|
|
/* exact non-re match, no more searching required */
|
|
return profile;
|
|
}
|
|
|
|
return candidate;
|
|
}
|
|
|
|
/**
|
|
* find_attach - do attachment search for unconfined processes
|
|
* @ns: the current namespace (NOT NULL)
|
|
* @list: list to search (NOT NULL)
|
|
* @name: the executable name to match against (NOT NULL)
|
|
*
|
|
* Returns: profile or NULL if no match found
|
|
*/
|
|
static struct aa_profile *find_attach(struct aa_namespace *ns,
|
|
struct list_head *list, const char *name)
|
|
{
|
|
struct aa_profile *profile;
|
|
|
|
read_lock(&ns->lock);
|
|
profile = aa_get_profile(__attach_match(name, list));
|
|
read_unlock(&ns->lock);
|
|
|
|
return profile;
|
|
}
|
|
|
|
/**
|
|
* separate_fqname - separate the namespace and profile names
|
|
* @fqname: the fqname name to split (NOT NULL)
|
|
* @ns_name: the namespace name if it exists (NOT NULL)
|
|
*
|
|
* This is the xtable equivalent routine of aa_split_fqname. It finds the
|
|
* split in an xtable fqname which contains an embedded \0 instead of a :
|
|
* if a namespace is specified. This is done so the xtable is constant and
|
|
* isn't re-split on every lookup.
|
|
*
|
|
* Either the profile or namespace name may be optional but if the namespace
|
|
* is specified the profile name termination must be present. This results
|
|
* in the following possible encodings:
|
|
* profile_name\0
|
|
* :ns_name\0profile_name\0
|
|
* :ns_name\0\0
|
|
*
|
|
* NOTE: the xtable fqname is pre-validated at load time in unpack_trans_table
|
|
*
|
|
* Returns: profile name if it is specified else NULL
|
|
*/
|
|
static const char *separate_fqname(const char *fqname, const char **ns_name)
|
|
{
|
|
const char *name;
|
|
|
|
if (fqname[0] == ':') {
|
|
/* In this case there is guaranteed to be two \0 terminators
|
|
* in the string. They are verified at load time by
|
|
* by unpack_trans_table
|
|
*/
|
|
*ns_name = fqname + 1; /* skip : */
|
|
name = *ns_name + strlen(*ns_name) + 1;
|
|
if (!*name)
|
|
name = NULL;
|
|
} else {
|
|
*ns_name = NULL;
|
|
name = fqname;
|
|
}
|
|
|
|
return name;
|
|
}
|
|
|
|
static const char *next_name(int xtype, const char *name)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* x_table_lookup - lookup an x transition name via transition table
|
|
* @profile: current profile (NOT NULL)
|
|
* @xindex: index into x transition table
|
|
*
|
|
* Returns: refcounted profile, or NULL on failure (MAYBE NULL)
|
|
*/
|
|
static struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex)
|
|
{
|
|
struct aa_profile *new_profile = NULL;
|
|
struct aa_namespace *ns = profile->ns;
|
|
u32 xtype = xindex & AA_X_TYPE_MASK;
|
|
int index = xindex & AA_X_INDEX_MASK;
|
|
const char *name;
|
|
|
|
/* index is guaranteed to be in range, validated at load time */
|
|
for (name = profile->file.trans.table[index]; !new_profile && name;
|
|
name = next_name(xtype, name)) {
|
|
struct aa_namespace *new_ns;
|
|
const char *xname = NULL;
|
|
|
|
new_ns = NULL;
|
|
if (xindex & AA_X_CHILD) {
|
|
/* release by caller */
|
|
new_profile = aa_find_child(profile, name);
|
|
continue;
|
|
} else if (*name == ':') {
|
|
/* switching namespace */
|
|
const char *ns_name;
|
|
xname = name = separate_fqname(name, &ns_name);
|
|
if (!xname)
|
|
/* no name so use profile name */
|
|
xname = profile->base.hname;
|
|
if (*ns_name == '@') {
|
|
/* TODO: variable support */
|
|
;
|
|
}
|
|
/* released below */
|
|
new_ns = aa_find_namespace(ns, ns_name);
|
|
if (!new_ns)
|
|
continue;
|
|
} else if (*name == '@') {
|
|
/* TODO: variable support */
|
|
continue;
|
|
} else {
|
|
/* basic namespace lookup */
|
|
xname = name;
|
|
}
|
|
|
|
/* released by caller */
|
|
new_profile = aa_lookup_profile(new_ns ? new_ns : ns, xname);
|
|
aa_put_namespace(new_ns);
|
|
}
|
|
|
|
/* released by caller */
|
|
return new_profile;
|
|
}
|
|
|
|
/**
|
|
* x_to_profile - get target profile for a given xindex
|
|
* @profile: current profile (NOT NULL)
|
|
* @name: name to lookup (NOT NULL)
|
|
* @xindex: index into x transition table
|
|
*
|
|
* find profile for a transition index
|
|
*
|
|
* Returns: refcounted profile or NULL if not found available
|
|
*/
|
|
static struct aa_profile *x_to_profile(struct aa_profile *profile,
|
|
const char *name, u32 xindex)
|
|
{
|
|
struct aa_profile *new_profile = NULL;
|
|
struct aa_namespace *ns = profile->ns;
|
|
u32 xtype = xindex & AA_X_TYPE_MASK;
|
|
|
|
switch (xtype) {
|
|
case AA_X_NONE:
|
|
/* fail exec unless ix || ux fallback - handled by caller */
|
|
return NULL;
|
|
case AA_X_NAME:
|
|
if (xindex & AA_X_CHILD)
|
|
/* released by caller */
|
|
new_profile = find_attach(ns, &profile->base.profiles,
|
|
name);
|
|
else
|
|
/* released by caller */
|
|
new_profile = find_attach(ns, &ns->base.profiles,
|
|
name);
|
|
break;
|
|
case AA_X_TABLE:
|
|
/* released by caller */
|
|
new_profile = x_table_lookup(profile, xindex);
|
|
break;
|
|
}
|
|
|
|
/* released by caller */
|
|
return new_profile;
|
|
}
|
|
|
|
/**
|
|
* apparmor_bprm_set_creds - set the new creds on the bprm struct
|
|
* @bprm: binprm for the exec (NOT NULL)
|
|
*
|
|
* Returns: %0 or error on failure
|
|
*/
|
|
int apparmor_bprm_set_creds(struct linux_binprm *bprm)
|
|
{
|
|
struct aa_task_cxt *cxt;
|
|
struct aa_profile *profile, *new_profile = NULL;
|
|
struct aa_namespace *ns;
|
|
char *buffer = NULL;
|
|
unsigned int state;
|
|
struct file_perms perms = {};
|
|
struct path_cond cond = {
|
|
bprm->file->f_path.dentry->d_inode->i_uid,
|
|
bprm->file->f_path.dentry->d_inode->i_mode
|
|
};
|
|
const char *name = NULL, *target = NULL, *info = NULL;
|
|
int error = cap_bprm_set_creds(bprm);
|
|
if (error)
|
|
return error;
|
|
|
|
if (bprm->cred_prepared)
|
|
return 0;
|
|
|
|
cxt = bprm->cred->security;
|
|
BUG_ON(!cxt);
|
|
|
|
profile = aa_get_profile(aa_newest_version(cxt->profile));
|
|
/*
|
|
* get the namespace from the replacement profile as replacement
|
|
* can change the namespace
|
|
*/
|
|
ns = profile->ns;
|
|
state = profile->file.start;
|
|
|
|
/* buffer freed below, name is pointer into buffer */
|
|
error = aa_get_name(&bprm->file->f_path, profile->path_flags, &buffer,
|
|
&name);
|
|
if (error) {
|
|
if (profile->flags &
|
|
(PFLAG_IX_ON_NAME_ERROR | PFLAG_UNCONFINED))
|
|
error = 0;
|
|
info = "Exec failed name resolution";
|
|
name = bprm->filename;
|
|
goto audit;
|
|
}
|
|
|
|
/* Test for onexec first as onexec directives override other
|
|
* x transitions.
|
|
*/
|
|
if (unconfined(profile)) {
|
|
/* unconfined task */
|
|
if (cxt->onexec)
|
|
/* change_profile on exec already been granted */
|
|
new_profile = aa_get_profile(cxt->onexec);
|
|
else
|
|
new_profile = find_attach(ns, &ns->base.profiles, name);
|
|
if (!new_profile)
|
|
goto cleanup;
|
|
goto apply;
|
|
}
|
|
|
|
/* find exec permissions for name */
|
|
state = aa_str_perms(profile->file.dfa, state, name, &cond, &perms);
|
|
if (cxt->onexec) {
|
|
struct file_perms cp;
|
|
info = "change_profile onexec";
|
|
if (!(perms.allow & AA_MAY_ONEXEC))
|
|
goto audit;
|
|
|
|
/* test if this exec can be paired with change_profile onexec.
|
|
* onexec permission is linked to exec with a standard pairing
|
|
* exec\0change_profile
|
|
*/
|
|
state = aa_dfa_null_transition(profile->file.dfa, state);
|
|
cp = change_profile_perms(profile, cxt->onexec->ns, name,
|
|
AA_MAY_ONEXEC, state);
|
|
|
|
if (!(cp.allow & AA_MAY_ONEXEC))
|
|
goto audit;
|
|
new_profile = aa_get_profile(aa_newest_version(cxt->onexec));
|
|
goto apply;
|
|
}
|
|
|
|
if (perms.allow & MAY_EXEC) {
|
|
/* exec permission determine how to transition */
|
|
new_profile = x_to_profile(profile, name, perms.xindex);
|
|
if (!new_profile) {
|
|
if (perms.xindex & AA_X_INHERIT) {
|
|
/* (p|c|n)ix - don't change profile but do
|
|
* use the newest version, which was picked
|
|
* up above when getting profile
|
|
*/
|
|
info = "ix fallback";
|
|
new_profile = aa_get_profile(profile);
|
|
goto x_clear;
|
|
} else if (perms.xindex & AA_X_UNCONFINED) {
|
|
new_profile = aa_get_profile(ns->unconfined);
|
|
info = "ux fallback";
|
|
} else {
|
|
error = -ENOENT;
|
|
info = "profile not found";
|
|
}
|
|
}
|
|
} else if (COMPLAIN_MODE(profile)) {
|
|
/* no exec permission - are we in learning mode */
|
|
new_profile = aa_new_null_profile(profile, 0);
|
|
if (!new_profile) {
|
|
error = -ENOMEM;
|
|
info = "could not create null profile";
|
|
} else {
|
|
error = -EACCES;
|
|
target = new_profile->base.hname;
|
|
}
|
|
perms.xindex |= AA_X_UNSAFE;
|
|
} else
|
|
/* fail exec */
|
|
error = -EACCES;
|
|
|
|
if (!new_profile)
|
|
goto audit;
|
|
|
|
if (bprm->unsafe & LSM_UNSAFE_SHARE) {
|
|
/* FIXME: currently don't mediate shared state */
|
|
;
|
|
}
|
|
|
|
if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
|
|
error = may_change_ptraced_domain(current, new_profile);
|
|
if (error) {
|
|
aa_put_profile(new_profile);
|
|
goto audit;
|
|
}
|
|
}
|
|
|
|
/* Determine if secure exec is needed.
|
|
* Can be at this point for the following reasons:
|
|
* 1. unconfined switching to confined
|
|
* 2. confined switching to different confinement
|
|
* 3. confined switching to unconfined
|
|
*
|
|
* Cases 2 and 3 are marked as requiring secure exec
|
|
* (unless policy specified "unsafe exec")
|
|
*
|
|
* bprm->unsafe is used to cache the AA_X_UNSAFE permission
|
|
* to avoid having to recompute in secureexec
|
|
*/
|
|
if (!(perms.xindex & AA_X_UNSAFE)) {
|
|
AA_DEBUG("scrubbing environment variables for %s profile=%s\n",
|
|
name, new_profile->base.hname);
|
|
bprm->unsafe |= AA_SECURE_X_NEEDED;
|
|
}
|
|
apply:
|
|
target = new_profile->base.hname;
|
|
/* when transitioning profiles clear unsafe personality bits */
|
|
bprm->per_clear |= PER_CLEAR_ON_SETID;
|
|
|
|
x_clear:
|
|
aa_put_profile(cxt->profile);
|
|
/* transfer new profile reference will be released when cxt is freed */
|
|
cxt->profile = new_profile;
|
|
|
|
/* clear out all temporary/transitional state from the context */
|
|
aa_put_profile(cxt->previous);
|
|
aa_put_profile(cxt->onexec);
|
|
cxt->previous = NULL;
|
|
cxt->onexec = NULL;
|
|
cxt->token = 0;
|
|
|
|
audit:
|
|
error = aa_audit_file(profile, &perms, GFP_KERNEL, OP_EXEC, MAY_EXEC,
|
|
name, target, cond.uid, info, error);
|
|
|
|
cleanup:
|
|
aa_put_profile(profile);
|
|
kfree(buffer);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* apparmor_bprm_secureexec - determine if secureexec is needed
|
|
* @bprm: binprm for exec (NOT NULL)
|
|
*
|
|
* Returns: %1 if secureexec is needed else %0
|
|
*/
|
|
int apparmor_bprm_secureexec(struct linux_binprm *bprm)
|
|
{
|
|
int ret = cap_bprm_secureexec(bprm);
|
|
|
|
/* the decision to use secure exec is computed in set_creds
|
|
* and stored in bprm->unsafe.
|
|
*/
|
|
if (!ret && (bprm->unsafe & AA_SECURE_X_NEEDED))
|
|
ret = 1;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* apparmor_bprm_committing_creds - do task cleanup on committing new creds
|
|
* @bprm: binprm for the exec (NOT NULL)
|
|
*/
|
|
void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
|
|
{
|
|
struct aa_profile *profile = __aa_current_profile();
|
|
struct aa_task_cxt *new_cxt = bprm->cred->security;
|
|
|
|
/* bail out if unconfined or not changing profile */
|
|
if ((new_cxt->profile == profile) ||
|
|
(unconfined(new_cxt->profile)))
|
|
return;
|
|
|
|
current->pdeath_signal = 0;
|
|
|
|
/* reset soft limits and set hard limits for the new profile */
|
|
__aa_transition_rlimits(profile, new_cxt->profile);
|
|
}
|
|
|
|
/**
|
|
* apparmor_bprm_commited_cred - do cleanup after new creds committed
|
|
* @bprm: binprm for the exec (NOT NULL)
|
|
*/
|
|
void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
|
|
{
|
|
/* TODO: cleanup signals - ipc mediation */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Functions for self directed profile change
|
|
*/
|
|
|
|
/**
|
|
* new_compound_name - create an hname with @n2 appended to @n1
|
|
* @n1: base of hname (NOT NULL)
|
|
* @n2: name to append (NOT NULL)
|
|
*
|
|
* Returns: new name or NULL on error
|
|
*/
|
|
static char *new_compound_name(const char *n1, const char *n2)
|
|
{
|
|
char *name = kmalloc(strlen(n1) + strlen(n2) + 3, GFP_KERNEL);
|
|
if (name)
|
|
sprintf(name, "%s//%s", n1, n2);
|
|
return name;
|
|
}
|
|
|
|
/**
|
|
* aa_change_hat - change hat to/from subprofile
|
|
* @hats: vector of hat names to try changing into (MAYBE NULL if @count == 0)
|
|
* @count: number of hat names in @hats
|
|
* @token: magic value to validate the hat change
|
|
* @permtest: true if this is just a permission test
|
|
*
|
|
* Change to the first profile specified in @hats that exists, and store
|
|
* the @hat_magic in the current task context. If the count == 0 and the
|
|
* @token matches that stored in the current task context, return to the
|
|
* top level profile.
|
|
*
|
|
* Returns %0 on success, error otherwise.
|
|
*/
|
|
int aa_change_hat(const char *hats[], int count, u64 token, bool permtest)
|
|
{
|
|
const struct cred *cred;
|
|
struct aa_task_cxt *cxt;
|
|
struct aa_profile *profile, *previous_profile, *hat = NULL;
|
|
char *name = NULL;
|
|
int i;
|
|
struct file_perms perms = {};
|
|
const char *target = NULL, *info = NULL;
|
|
int error = 0;
|
|
|
|
/* released below */
|
|
cred = get_current_cred();
|
|
cxt = cred->security;
|
|
profile = aa_cred_profile(cred);
|
|
previous_profile = cxt->previous;
|
|
|
|
if (unconfined(profile)) {
|
|
info = "unconfined";
|
|
error = -EPERM;
|
|
goto audit;
|
|
}
|
|
|
|
if (count) {
|
|
/* attempting to change into a new hat or switch to a sibling */
|
|
struct aa_profile *root;
|
|
root = PROFILE_IS_HAT(profile) ? profile->parent : profile;
|
|
|
|
/* find first matching hat */
|
|
for (i = 0; i < count && !hat; i++)
|
|
/* released below */
|
|
hat = aa_find_child(root, hats[i]);
|
|
if (!hat) {
|
|
if (!COMPLAIN_MODE(root) || permtest) {
|
|
if (list_empty(&root->base.profiles))
|
|
error = -ECHILD;
|
|
else
|
|
error = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* In complain mode and failed to match any hats.
|
|
* Audit the failure is based off of the first hat
|
|
* supplied. This is done due how userspace
|
|
* interacts with change_hat.
|
|
*
|
|
* TODO: Add logging of all failed hats
|
|
*/
|
|
|
|
/* freed below */
|
|
name = new_compound_name(root->base.hname, hats[0]);
|
|
target = name;
|
|
/* released below */
|
|
hat = aa_new_null_profile(profile, 1);
|
|
if (!hat) {
|
|
info = "failed null profile create";
|
|
error = -ENOMEM;
|
|
goto audit;
|
|
}
|
|
} else {
|
|
target = hat->base.hname;
|
|
if (!PROFILE_IS_HAT(hat)) {
|
|
info = "target not hat";
|
|
error = -EPERM;
|
|
goto audit;
|
|
}
|
|
}
|
|
|
|
error = may_change_ptraced_domain(current, hat);
|
|
if (error) {
|
|
info = "ptraced";
|
|
error = -EPERM;
|
|
goto audit;
|
|
}
|
|
|
|
if (!permtest) {
|
|
error = aa_set_current_hat(hat, token);
|
|
if (error == -EACCES)
|
|
/* kill task in case of brute force attacks */
|
|
perms.kill = AA_MAY_CHANGEHAT;
|
|
else if (name && !error)
|
|
/* reset error for learning of new hats */
|
|
error = -ENOENT;
|
|
}
|
|
} else if (previous_profile) {
|
|
/* Return to saved profile. Kill task if restore fails
|
|
* to avoid brute force attacks
|
|
*/
|
|
target = previous_profile->base.hname;
|
|
error = aa_restore_previous_profile(token);
|
|
perms.kill = AA_MAY_CHANGEHAT;
|
|
} else
|
|
/* ignore restores when there is no saved profile */
|
|
goto out;
|
|
|
|
audit:
|
|
if (!permtest)
|
|
error = aa_audit_file(profile, &perms, GFP_KERNEL,
|
|
OP_CHANGE_HAT, AA_MAY_CHANGEHAT, NULL,
|
|
target, 0, info, error);
|
|
|
|
out:
|
|
aa_put_profile(hat);
|
|
kfree(name);
|
|
put_cred(cred);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* aa_change_profile - perform a one-way profile transition
|
|
* @ns_name: name of the profile namespace to change to (MAYBE NULL)
|
|
* @hname: name of profile to change to (MAYBE NULL)
|
|
* @onexec: whether this transition is to take place immediately or at exec
|
|
* @permtest: true if this is just a permission test
|
|
*
|
|
* Change to new profile @name. Unlike with hats, there is no way
|
|
* to change back. If @name isn't specified the current profile name is
|
|
* used.
|
|
* If @onexec then the transition is delayed until
|
|
* the next exec.
|
|
*
|
|
* Returns %0 on success, error otherwise.
|
|
*/
|
|
int aa_change_profile(const char *ns_name, const char *hname, bool onexec,
|
|
bool permtest)
|
|
{
|
|
const struct cred *cred;
|
|
struct aa_task_cxt *cxt;
|
|
struct aa_profile *profile, *target = NULL;
|
|
struct aa_namespace *ns = NULL;
|
|
struct file_perms perms = {};
|
|
const char *name = NULL, *info = NULL;
|
|
int op, error = 0;
|
|
u32 request;
|
|
|
|
if (!hname && !ns_name)
|
|
return -EINVAL;
|
|
|
|
if (onexec) {
|
|
request = AA_MAY_ONEXEC;
|
|
op = OP_CHANGE_ONEXEC;
|
|
} else {
|
|
request = AA_MAY_CHANGE_PROFILE;
|
|
op = OP_CHANGE_PROFILE;
|
|
}
|
|
|
|
cred = get_current_cred();
|
|
cxt = cred->security;
|
|
profile = aa_cred_profile(cred);
|
|
|
|
if (ns_name) {
|
|
/* released below */
|
|
ns = aa_find_namespace(profile->ns, ns_name);
|
|
if (!ns) {
|
|
/* we don't create new namespace in complain mode */
|
|
name = ns_name;
|
|
info = "namespace not found";
|
|
error = -ENOENT;
|
|
goto audit;
|
|
}
|
|
} else
|
|
/* released below */
|
|
ns = aa_get_namespace(profile->ns);
|
|
|
|
/* if the name was not specified, use the name of the current profile */
|
|
if (!hname) {
|
|
if (unconfined(profile))
|
|
hname = ns->unconfined->base.hname;
|
|
else
|
|
hname = profile->base.hname;
|
|
}
|
|
|
|
perms = change_profile_perms(profile, ns, hname, request,
|
|
profile->file.start);
|
|
if (!(perms.allow & request)) {
|
|
error = -EACCES;
|
|
goto audit;
|
|
}
|
|
|
|
/* released below */
|
|
target = aa_lookup_profile(ns, hname);
|
|
if (!target) {
|
|
info = "profile not found";
|
|
error = -ENOENT;
|
|
if (permtest || !COMPLAIN_MODE(profile))
|
|
goto audit;
|
|
/* released below */
|
|
target = aa_new_null_profile(profile, 0);
|
|
if (!target) {
|
|
info = "failed null profile create";
|
|
error = -ENOMEM;
|
|
goto audit;
|
|
}
|
|
}
|
|
|
|
/* check if tracing task is allowed to trace target domain */
|
|
error = may_change_ptraced_domain(current, target);
|
|
if (error) {
|
|
info = "ptrace prevents transition";
|
|
goto audit;
|
|
}
|
|
|
|
if (permtest)
|
|
goto audit;
|
|
|
|
if (onexec)
|
|
error = aa_set_current_onexec(target);
|
|
else
|
|
error = aa_replace_current_profile(target);
|
|
|
|
audit:
|
|
if (!permtest)
|
|
error = aa_audit_file(profile, &perms, GFP_KERNEL, op, request,
|
|
name, hname, 0, info, error);
|
|
|
|
aa_put_namespace(ns);
|
|
aa_put_profile(target);
|
|
put_cred(cred);
|
|
|
|
return error;
|
|
}
|