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1460 lines
38 KiB
1460 lines
38 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
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* AppArmor security module |
|
* |
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* This file contains AppArmor policy attachment and domain transitions |
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* |
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* Copyright (C) 2002-2008 Novell/SUSE |
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* Copyright 2009-2010 Canonical Ltd. |
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*/ |
|
|
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#include <linux/errno.h> |
|
#include <linux/fdtable.h> |
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#include <linux/fs.h> |
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#include <linux/file.h> |
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#include <linux/mount.h> |
|
#include <linux/syscalls.h> |
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#include <linux/tracehook.h> |
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#include <linux/personality.h> |
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#include <linux/xattr.h> |
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#include <linux/user_namespace.h> |
|
|
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#include "include/audit.h" |
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#include "include/apparmorfs.h" |
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#include "include/cred.h" |
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#include "include/domain.h" |
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#include "include/file.h" |
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#include "include/ipc.h" |
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#include "include/match.h" |
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#include "include/path.h" |
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#include "include/policy.h" |
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#include "include/policy_ns.h" |
|
|
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/** |
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* aa_free_domain_entries - free entries in a domain table |
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* @domain: the domain table to free (MAYBE NULL) |
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*/ |
|
void aa_free_domain_entries(struct aa_domain *domain) |
|
{ |
|
int i; |
|
if (domain) { |
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if (!domain->table) |
|
return; |
|
|
|
for (i = 0; i < domain->size; i++) |
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kfree_sensitive(domain->table[i]); |
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kfree_sensitive(domain->table); |
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domain->table = NULL; |
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} |
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} |
|
|
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/** |
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* may_change_ptraced_domain - check if can change profile on ptraced task |
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* @to_label: profile to change to (NOT NULL) |
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* @info: message if there is an error |
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* |
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* Check if current is ptraced and if so if the tracing task is allowed |
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* to trace the new domain |
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* |
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* Returns: %0 or error if change not allowed |
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*/ |
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static int may_change_ptraced_domain(struct aa_label *to_label, |
|
const char **info) |
|
{ |
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struct task_struct *tracer; |
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struct aa_label *tracerl = NULL; |
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int error = 0; |
|
|
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rcu_read_lock(); |
|
tracer = ptrace_parent(current); |
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if (tracer) |
|
/* released below */ |
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tracerl = aa_get_task_label(tracer); |
|
|
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/* not ptraced */ |
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if (!tracer || unconfined(tracerl)) |
|
goto out; |
|
|
|
error = aa_may_ptrace(tracerl, to_label, PTRACE_MODE_ATTACH); |
|
|
|
out: |
|
rcu_read_unlock(); |
|
aa_put_label(tracerl); |
|
|
|
if (error) |
|
*info = "ptrace prevents transition"; |
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return error; |
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} |
|
|
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/**** TODO: dedup to aa_label_match - needs perm and dfa, merging |
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* specifically this is an exact copy of aa_label_match except |
|
* aa_compute_perms is replaced with aa_compute_fperms |
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* and policy.dfa with file.dfa |
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****/ |
|
/* match a profile and its associated ns component if needed |
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* Assumes visibility test has already been done. |
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* If a subns profile is not to be matched should be prescreened with |
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* visibility test. |
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*/ |
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static inline unsigned int match_component(struct aa_profile *profile, |
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struct aa_profile *tp, |
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bool stack, unsigned int state) |
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{ |
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const char *ns_name; |
|
|
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if (stack) |
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state = aa_dfa_match(profile->file.dfa, state, "&"); |
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if (profile->ns == tp->ns) |
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return aa_dfa_match(profile->file.dfa, state, tp->base.hname); |
|
|
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/* try matching with namespace name and then profile */ |
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ns_name = aa_ns_name(profile->ns, tp->ns, true); |
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state = aa_dfa_match_len(profile->file.dfa, state, ":", 1); |
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state = aa_dfa_match(profile->file.dfa, state, ns_name); |
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state = aa_dfa_match_len(profile->file.dfa, state, ":", 1); |
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return aa_dfa_match(profile->file.dfa, state, tp->base.hname); |
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} |
|
|
|
/** |
|
* label_compound_match - find perms for full compound label |
|
* @profile: profile to find perms for |
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* @label: label to check access permissions for |
|
* @stack: whether this is a stacking request |
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* @start: state to start match in |
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* @subns: whether to do permission checks on components in a subns |
|
* @request: permissions to request |
|
* @perms: perms struct to set |
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* |
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* Returns: 0 on success else ERROR |
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* |
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* For the label A//&B//&C this does the perm match for A//&B//&C |
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* @perms should be preinitialized with allperms OR a previous permission |
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* check to be stacked. |
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*/ |
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static int label_compound_match(struct aa_profile *profile, |
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struct aa_label *label, bool stack, |
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unsigned int state, bool subns, u32 request, |
|
struct aa_perms *perms) |
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{ |
|
struct aa_profile *tp; |
|
struct label_it i; |
|
struct path_cond cond = { }; |
|
|
|
/* find first subcomponent that is visible */ |
|
label_for_each(i, label, tp) { |
|
if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
|
continue; |
|
state = match_component(profile, tp, stack, state); |
|
if (!state) |
|
goto fail; |
|
goto next; |
|
} |
|
|
|
/* no component visible */ |
|
*perms = allperms; |
|
return 0; |
|
|
|
next: |
|
label_for_each_cont(i, label, tp) { |
|
if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
|
continue; |
|
state = aa_dfa_match(profile->file.dfa, state, "//&"); |
|
state = match_component(profile, tp, false, state); |
|
if (!state) |
|
goto fail; |
|
} |
|
*perms = aa_compute_fperms(profile->file.dfa, state, &cond); |
|
aa_apply_modes_to_perms(profile, perms); |
|
if ((perms->allow & request) != request) |
|
return -EACCES; |
|
|
|
return 0; |
|
|
|
fail: |
|
*perms = nullperms; |
|
return -EACCES; |
|
} |
|
|
|
/** |
|
* label_components_match - find perms for all subcomponents of a label |
|
* @profile: profile to find perms for |
|
* @label: label to check access permissions for |
|
* @stack: whether this is a stacking request |
|
* @start: state to start match in |
|
* @subns: whether to do permission checks on components in a subns |
|
* @request: permissions to request |
|
* @perms: an initialized perms struct to add accumulation to |
|
* |
|
* Returns: 0 on success else ERROR |
|
* |
|
* For the label A//&B//&C this does the perm match for each of A and B and C |
|
* @perms should be preinitialized with allperms OR a previous permission |
|
* check to be stacked. |
|
*/ |
|
static int label_components_match(struct aa_profile *profile, |
|
struct aa_label *label, bool stack, |
|
unsigned int start, bool subns, u32 request, |
|
struct aa_perms *perms) |
|
{ |
|
struct aa_profile *tp; |
|
struct label_it i; |
|
struct aa_perms tmp; |
|
struct path_cond cond = { }; |
|
unsigned int state = 0; |
|
|
|
/* find first subcomponent to test */ |
|
label_for_each(i, label, tp) { |
|
if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
|
continue; |
|
state = match_component(profile, tp, stack, start); |
|
if (!state) |
|
goto fail; |
|
goto next; |
|
} |
|
|
|
/* no subcomponents visible - no change in perms */ |
|
return 0; |
|
|
|
next: |
|
tmp = aa_compute_fperms(profile->file.dfa, state, &cond); |
|
aa_apply_modes_to_perms(profile, &tmp); |
|
aa_perms_accum(perms, &tmp); |
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label_for_each_cont(i, label, tp) { |
|
if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
|
continue; |
|
state = match_component(profile, tp, stack, start); |
|
if (!state) |
|
goto fail; |
|
tmp = aa_compute_fperms(profile->file.dfa, state, &cond); |
|
aa_apply_modes_to_perms(profile, &tmp); |
|
aa_perms_accum(perms, &tmp); |
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} |
|
|
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if ((perms->allow & request) != request) |
|
return -EACCES; |
|
|
|
return 0; |
|
|
|
fail: |
|
*perms = nullperms; |
|
return -EACCES; |
|
} |
|
|
|
/** |
|
* label_match - do a multi-component label match |
|
* @profile: profile to match against (NOT NULL) |
|
* @label: label to match (NOT NULL) |
|
* @stack: whether this is a stacking request |
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* @state: state to start in |
|
* @subns: whether to match subns components |
|
* @request: permission request |
|
* @perms: Returns computed perms (NOT NULL) |
|
* |
|
* Returns: the state the match finished in, may be the none matching state |
|
*/ |
|
static int label_match(struct aa_profile *profile, struct aa_label *label, |
|
bool stack, unsigned int state, bool subns, u32 request, |
|
struct aa_perms *perms) |
|
{ |
|
int error; |
|
|
|
*perms = nullperms; |
|
error = label_compound_match(profile, label, stack, state, subns, |
|
request, perms); |
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if (!error) |
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return error; |
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|
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*perms = allperms; |
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return label_components_match(profile, label, stack, state, subns, |
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request, perms); |
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} |
|
|
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/******* end TODO: dedup *****/ |
|
|
|
/** |
|
* change_profile_perms - find permissions for change_profile |
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* @profile: the current profile (NOT NULL) |
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* @target: label to transition to (NOT NULL) |
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* @stack: whether this is a stacking request |
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* @request: requested perms |
|
* @start: state to start matching in |
|
* |
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* |
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* Returns: permission set |
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* |
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* currently only matches full label A//&B//&C or individual components A, B, C |
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* not arbitrary combinations. Eg. A//&B, C |
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*/ |
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static int change_profile_perms(struct aa_profile *profile, |
|
struct aa_label *target, bool stack, |
|
u32 request, unsigned int start, |
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struct aa_perms *perms) |
|
{ |
|
if (profile_unconfined(profile)) { |
|
perms->allow = AA_MAY_CHANGE_PROFILE | AA_MAY_ONEXEC; |
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perms->audit = perms->quiet = perms->kill = 0; |
|
return 0; |
|
} |
|
|
|
/* TODO: add profile in ns screening */ |
|
return label_match(profile, target, stack, start, true, request, perms); |
|
} |
|
|
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/** |
|
* aa_xattrs_match - check whether a file matches the xattrs defined in profile |
|
* @bprm: binprm struct for the process to validate |
|
* @profile: profile to match against (NOT NULL) |
|
* @state: state to start match in |
|
* |
|
* Returns: number of extended attributes that matched, or < 0 on error |
|
*/ |
|
static int aa_xattrs_match(const struct linux_binprm *bprm, |
|
struct aa_profile *profile, unsigned int state) |
|
{ |
|
int i; |
|
ssize_t size; |
|
struct dentry *d; |
|
char *value = NULL; |
|
int value_size = 0, ret = profile->xattr_count; |
|
|
|
if (!bprm || !profile->xattr_count) |
|
return 0; |
|
might_sleep(); |
|
|
|
/* transition from exec match to xattr set */ |
|
state = aa_dfa_outofband_transition(profile->xmatch, state); |
|
d = bprm->file->f_path.dentry; |
|
|
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for (i = 0; i < profile->xattr_count; i++) { |
|
size = vfs_getxattr_alloc(&init_user_ns, d, profile->xattrs[i], |
|
&value, value_size, GFP_KERNEL); |
|
if (size >= 0) { |
|
u32 perm; |
|
|
|
/* |
|
* Check the xattr presence before value. This ensure |
|
* that not present xattr can be distinguished from a 0 |
|
* length value or rule that matches any value |
|
*/ |
|
state = aa_dfa_null_transition(profile->xmatch, state); |
|
/* Check xattr value */ |
|
state = aa_dfa_match_len(profile->xmatch, state, value, |
|
size); |
|
perm = dfa_user_allow(profile->xmatch, state); |
|
if (!(perm & MAY_EXEC)) { |
|
ret = -EINVAL; |
|
goto out; |
|
} |
|
} |
|
/* transition to next element */ |
|
state = aa_dfa_outofband_transition(profile->xmatch, state); |
|
if (size < 0) { |
|
/* |
|
* No xattr match, so verify if transition to |
|
* next element was valid. IFF so the xattr |
|
* was optional. |
|
*/ |
|
if (!state) { |
|
ret = -EINVAL; |
|
goto out; |
|
} |
|
/* don't count missing optional xattr as matched */ |
|
ret--; |
|
} |
|
} |
|
|
|
out: |
|
kfree(value); |
|
return ret; |
|
} |
|
|
|
/** |
|
* find_attach - do attachment search for unconfined processes |
|
* @bprm - binprm structure of transitioning task |
|
* @ns: the current namespace (NOT NULL) |
|
* @head - profile list to walk (NOT NULL) |
|
* @name - to match against (NOT NULL) |
|
* @info - info message if there was an error (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: label or NULL if no match found |
|
*/ |
|
static struct aa_label *find_attach(const struct linux_binprm *bprm, |
|
struct aa_ns *ns, struct list_head *head, |
|
const char *name, const char **info) |
|
{ |
|
int candidate_len = 0, candidate_xattrs = 0; |
|
bool conflict = false; |
|
struct aa_profile *profile, *candidate = NULL; |
|
|
|
AA_BUG(!name); |
|
AA_BUG(!head); |
|
|
|
rcu_read_lock(); |
|
restart: |
|
list_for_each_entry_rcu(profile, head, base.list) { |
|
if (profile->label.flags & FLAG_NULL && |
|
&profile->label == ns_unconfined(profile->ns)) |
|
continue; |
|
|
|
/* Find the "best" matching profile. Profiles must |
|
* match the path and extended attributes (if any) |
|
* associated with the file. A more specific path |
|
* match will be preferred over a less specific one, |
|
* and a match with more matching extended attributes |
|
* will be preferred over one with fewer. If the best |
|
* match has both the same level of path specificity |
|
* and the same number of matching extended attributes |
|
* as another profile, signal a conflict and refuse to |
|
* match. |
|
*/ |
|
if (profile->xmatch) { |
|
unsigned int state, count; |
|
u32 perm; |
|
|
|
state = aa_dfa_leftmatch(profile->xmatch, DFA_START, |
|
name, &count); |
|
perm = dfa_user_allow(profile->xmatch, state); |
|
/* any accepting state means a valid match. */ |
|
if (perm & MAY_EXEC) { |
|
int ret = 0; |
|
|
|
if (count < candidate_len) |
|
continue; |
|
|
|
if (bprm && profile->xattr_count) { |
|
long rev = READ_ONCE(ns->revision); |
|
|
|
if (!aa_get_profile_not0(profile)) |
|
goto restart; |
|
rcu_read_unlock(); |
|
ret = aa_xattrs_match(bprm, profile, |
|
state); |
|
rcu_read_lock(); |
|
aa_put_profile(profile); |
|
if (rev != |
|
READ_ONCE(ns->revision)) |
|
/* policy changed */ |
|
goto restart; |
|
/* |
|
* Fail matching if the xattrs don't |
|
* match |
|
*/ |
|
if (ret < 0) |
|
continue; |
|
} |
|
/* |
|
* TODO: allow for more flexible best match |
|
* |
|
* The new match isn't more specific |
|
* than the current best match |
|
*/ |
|
if (count == candidate_len && |
|
ret <= candidate_xattrs) { |
|
/* Match is equivalent, so conflict */ |
|
if (ret == candidate_xattrs) |
|
conflict = true; |
|
continue; |
|
} |
|
|
|
/* Either the same length with more matching |
|
* xattrs, or a longer match |
|
*/ |
|
candidate = profile; |
|
candidate_len = profile->xmatch_len; |
|
candidate_xattrs = ret; |
|
conflict = false; |
|
} |
|
} else if (!strcmp(profile->base.name, name)) { |
|
/* |
|
* old exact non-re match, without conditionals such |
|
* as xattrs. no more searching required |
|
*/ |
|
candidate = profile; |
|
goto out; |
|
} |
|
} |
|
|
|
if (!candidate || conflict) { |
|
if (conflict) |
|
*info = "conflicting profile attachments"; |
|
rcu_read_unlock(); |
|
return NULL; |
|
} |
|
|
|
out: |
|
candidate = aa_get_newest_profile(candidate); |
|
rcu_read_unlock(); |
|
|
|
return &candidate->label; |
|
} |
|
|
|
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 |
|
* @name: returns: name tested to find label (NOT NULL) |
|
* |
|
* Returns: refcounted label, or NULL on failure (MAYBE NULL) |
|
*/ |
|
struct aa_label *x_table_lookup(struct aa_profile *profile, u32 xindex, |
|
const char **name) |
|
{ |
|
struct aa_label *label = NULL; |
|
u32 xtype = xindex & AA_X_TYPE_MASK; |
|
int index = xindex & AA_X_INDEX_MASK; |
|
|
|
AA_BUG(!name); |
|
|
|
/* index is guaranteed to be in range, validated at load time */ |
|
/* TODO: move lookup parsing to unpack time so this is a straight |
|
* index into the resultant label |
|
*/ |
|
for (*name = profile->file.trans.table[index]; !label && *name; |
|
*name = next_name(xtype, *name)) { |
|
if (xindex & AA_X_CHILD) { |
|
struct aa_profile *new_profile; |
|
/* release by caller */ |
|
new_profile = aa_find_child(profile, *name); |
|
if (new_profile) |
|
label = &new_profile->label; |
|
continue; |
|
} |
|
label = aa_label_parse(&profile->label, *name, GFP_KERNEL, |
|
true, false); |
|
if (IS_ERR(label)) |
|
label = NULL; |
|
} |
|
|
|
/* released by caller */ |
|
|
|
return label; |
|
} |
|
|
|
/** |
|
* x_to_label - get target label for a given xindex |
|
* @profile: current profile (NOT NULL) |
|
* @bprm: binprm structure of transitioning task |
|
* @name: name to lookup (NOT NULL) |
|
* @xindex: index into x transition table |
|
* @lookupname: returns: name used in lookup if one was specified (NOT NULL) |
|
* |
|
* find label for a transition index |
|
* |
|
* Returns: refcounted label or NULL if not found available |
|
*/ |
|
static struct aa_label *x_to_label(struct aa_profile *profile, |
|
const struct linux_binprm *bprm, |
|
const char *name, u32 xindex, |
|
const char **lookupname, |
|
const char **info) |
|
{ |
|
struct aa_label *new = NULL; |
|
struct aa_ns *ns = profile->ns; |
|
u32 xtype = xindex & AA_X_TYPE_MASK; |
|
const char *stack = NULL; |
|
|
|
switch (xtype) { |
|
case AA_X_NONE: |
|
/* fail exec unless ix || ux fallback - handled by caller */ |
|
*lookupname = NULL; |
|
break; |
|
case AA_X_TABLE: |
|
/* TODO: fix when perm mapping done at unload */ |
|
stack = profile->file.trans.table[xindex & AA_X_INDEX_MASK]; |
|
if (*stack != '&') { |
|
/* released by caller */ |
|
new = x_table_lookup(profile, xindex, lookupname); |
|
stack = NULL; |
|
break; |
|
} |
|
fallthrough; /* to X_NAME */ |
|
case AA_X_NAME: |
|
if (xindex & AA_X_CHILD) |
|
/* released by caller */ |
|
new = find_attach(bprm, ns, &profile->base.profiles, |
|
name, info); |
|
else |
|
/* released by caller */ |
|
new = find_attach(bprm, ns, &ns->base.profiles, |
|
name, info); |
|
*lookupname = name; |
|
break; |
|
} |
|
|
|
if (!new) { |
|
if (xindex & AA_X_INHERIT) { |
|
/* (p|c|n)ix - don't change profile but do |
|
* use the newest version |
|
*/ |
|
*info = "ix fallback"; |
|
/* no profile && no error */ |
|
new = aa_get_newest_label(&profile->label); |
|
} else if (xindex & AA_X_UNCONFINED) { |
|
new = aa_get_newest_label(ns_unconfined(profile->ns)); |
|
*info = "ux fallback"; |
|
} |
|
} |
|
|
|
if (new && stack) { |
|
/* base the stack on post domain transition */ |
|
struct aa_label *base = new; |
|
|
|
new = aa_label_parse(base, stack, GFP_KERNEL, true, false); |
|
if (IS_ERR(new)) |
|
new = NULL; |
|
aa_put_label(base); |
|
} |
|
|
|
/* released by caller */ |
|
return new; |
|
} |
|
|
|
static struct aa_label *profile_transition(struct aa_profile *profile, |
|
const struct linux_binprm *bprm, |
|
char *buffer, struct path_cond *cond, |
|
bool *secure_exec) |
|
{ |
|
struct aa_label *new = NULL; |
|
const char *info = NULL, *name = NULL, *target = NULL; |
|
unsigned int state = profile->file.start; |
|
struct aa_perms perms = {}; |
|
bool nonewprivs = false; |
|
int error = 0; |
|
|
|
AA_BUG(!profile); |
|
AA_BUG(!bprm); |
|
AA_BUG(!buffer); |
|
|
|
error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer, |
|
&name, &info, profile->disconnected); |
|
if (error) { |
|
if (profile_unconfined(profile) || |
|
(profile->label.flags & FLAG_IX_ON_NAME_ERROR)) { |
|
AA_DEBUG("name lookup ix on error"); |
|
error = 0; |
|
new = aa_get_newest_label(&profile->label); |
|
} |
|
name = bprm->filename; |
|
goto audit; |
|
} |
|
|
|
if (profile_unconfined(profile)) { |
|
new = find_attach(bprm, profile->ns, |
|
&profile->ns->base.profiles, name, &info); |
|
if (new) { |
|
AA_DEBUG("unconfined attached to new label"); |
|
return new; |
|
} |
|
AA_DEBUG("unconfined exec no attachment"); |
|
return aa_get_newest_label(&profile->label); |
|
} |
|
|
|
/* find exec permissions for name */ |
|
state = aa_str_perms(profile->file.dfa, state, name, cond, &perms); |
|
if (perms.allow & MAY_EXEC) { |
|
/* exec permission determine how to transition */ |
|
new = x_to_label(profile, bprm, name, perms.xindex, &target, |
|
&info); |
|
if (new && new->proxy == profile->label.proxy && info) { |
|
/* hack ix fallback - improve how this is detected */ |
|
goto audit; |
|
} else if (!new) { |
|
error = -EACCES; |
|
info = "profile transition not found"; |
|
/* remove MAY_EXEC to audit as failure */ |
|
perms.allow &= ~MAY_EXEC; |
|
} |
|
} else if (COMPLAIN_MODE(profile)) { |
|
/* no exec permission - learning mode */ |
|
struct aa_profile *new_profile = NULL; |
|
|
|
new_profile = aa_new_null_profile(profile, false, name, |
|
GFP_KERNEL); |
|
if (!new_profile) { |
|
error = -ENOMEM; |
|
info = "could not create null profile"; |
|
} else { |
|
error = -EACCES; |
|
new = &new_profile->label; |
|
} |
|
perms.xindex |= AA_X_UNSAFE; |
|
} else |
|
/* fail exec */ |
|
error = -EACCES; |
|
|
|
if (!new) |
|
goto audit; |
|
|
|
|
|
if (!(perms.xindex & AA_X_UNSAFE)) { |
|
if (DEBUG_ON) { |
|
dbg_printk("apparmor: scrubbing environment variables" |
|
" for %s profile=", name); |
|
aa_label_printk(new, GFP_KERNEL); |
|
dbg_printk("\n"); |
|
} |
|
*secure_exec = true; |
|
} |
|
|
|
audit: |
|
aa_audit_file(profile, &perms, OP_EXEC, MAY_EXEC, name, target, new, |
|
cond->uid, info, error); |
|
if (!new || nonewprivs) { |
|
aa_put_label(new); |
|
return ERR_PTR(error); |
|
} |
|
|
|
return new; |
|
} |
|
|
|
static int profile_onexec(struct aa_profile *profile, struct aa_label *onexec, |
|
bool stack, const struct linux_binprm *bprm, |
|
char *buffer, struct path_cond *cond, |
|
bool *secure_exec) |
|
{ |
|
unsigned int state = profile->file.start; |
|
struct aa_perms perms = {}; |
|
const char *xname = NULL, *info = "change_profile onexec"; |
|
int error = -EACCES; |
|
|
|
AA_BUG(!profile); |
|
AA_BUG(!onexec); |
|
AA_BUG(!bprm); |
|
AA_BUG(!buffer); |
|
|
|
if (profile_unconfined(profile)) { |
|
/* change_profile on exec already granted */ |
|
/* |
|
* NOTE: Domain transitions from unconfined are allowed |
|
* even when no_new_privs is set because this aways results |
|
* in a further reduction of permissions. |
|
*/ |
|
return 0; |
|
} |
|
|
|
error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer, |
|
&xname, &info, profile->disconnected); |
|
if (error) { |
|
if (profile_unconfined(profile) || |
|
(profile->label.flags & FLAG_IX_ON_NAME_ERROR)) { |
|
AA_DEBUG("name lookup ix on error"); |
|
error = 0; |
|
} |
|
xname = bprm->filename; |
|
goto audit; |
|
} |
|
|
|
/* find exec permissions for name */ |
|
state = aa_str_perms(profile->file.dfa, state, xname, cond, &perms); |
|
if (!(perms.allow & AA_MAY_ONEXEC)) { |
|
info = "no change_onexec valid for executable"; |
|
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); |
|
error = change_profile_perms(profile, onexec, stack, AA_MAY_ONEXEC, |
|
state, &perms); |
|
if (error) { |
|
perms.allow &= ~AA_MAY_ONEXEC; |
|
goto audit; |
|
} |
|
|
|
if (!(perms.xindex & AA_X_UNSAFE)) { |
|
if (DEBUG_ON) { |
|
dbg_printk("apparmor: scrubbing environment " |
|
"variables for %s label=", xname); |
|
aa_label_printk(onexec, GFP_KERNEL); |
|
dbg_printk("\n"); |
|
} |
|
*secure_exec = true; |
|
} |
|
|
|
audit: |
|
return aa_audit_file(profile, &perms, OP_EXEC, AA_MAY_ONEXEC, xname, |
|
NULL, onexec, cond->uid, info, error); |
|
} |
|
|
|
/* ensure none ns domain transitions are correctly applied with onexec */ |
|
|
|
static struct aa_label *handle_onexec(struct aa_label *label, |
|
struct aa_label *onexec, bool stack, |
|
const struct linux_binprm *bprm, |
|
char *buffer, struct path_cond *cond, |
|
bool *unsafe) |
|
{ |
|
struct aa_profile *profile; |
|
struct aa_label *new; |
|
int error; |
|
|
|
AA_BUG(!label); |
|
AA_BUG(!onexec); |
|
AA_BUG(!bprm); |
|
AA_BUG(!buffer); |
|
|
|
if (!stack) { |
|
error = fn_for_each_in_ns(label, profile, |
|
profile_onexec(profile, onexec, stack, |
|
bprm, buffer, cond, unsafe)); |
|
if (error) |
|
return ERR_PTR(error); |
|
new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
|
aa_get_newest_label(onexec), |
|
profile_transition(profile, bprm, buffer, |
|
cond, unsafe)); |
|
|
|
} else { |
|
/* TODO: determine how much we want to loosen this */ |
|
error = fn_for_each_in_ns(label, profile, |
|
profile_onexec(profile, onexec, stack, bprm, |
|
buffer, cond, unsafe)); |
|
if (error) |
|
return ERR_PTR(error); |
|
new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
|
aa_label_merge(&profile->label, onexec, |
|
GFP_KERNEL), |
|
profile_transition(profile, bprm, buffer, |
|
cond, unsafe)); |
|
} |
|
|
|
if (new) |
|
return new; |
|
|
|
/* TODO: get rid of GLOBAL_ROOT_UID */ |
|
error = fn_for_each_in_ns(label, profile, |
|
aa_audit_file(profile, &nullperms, OP_CHANGE_ONEXEC, |
|
AA_MAY_ONEXEC, bprm->filename, NULL, |
|
onexec, GLOBAL_ROOT_UID, |
|
"failed to build target label", -ENOMEM)); |
|
return ERR_PTR(error); |
|
} |
|
|
|
/** |
|
* apparmor_bprm_creds_for_exec - Update the new creds on the bprm struct |
|
* @bprm: binprm for the exec (NOT NULL) |
|
* |
|
* Returns: %0 or error on failure |
|
* |
|
* TODO: once the other paths are done see if we can't refactor into a fn |
|
*/ |
|
int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm) |
|
{ |
|
struct aa_task_ctx *ctx; |
|
struct aa_label *label, *new = NULL; |
|
struct aa_profile *profile; |
|
char *buffer = NULL; |
|
const char *info = NULL; |
|
int error = 0; |
|
bool unsafe = false; |
|
kuid_t i_uid = i_uid_into_mnt(file_mnt_user_ns(bprm->file), |
|
file_inode(bprm->file)); |
|
struct path_cond cond = { |
|
i_uid, |
|
file_inode(bprm->file)->i_mode |
|
}; |
|
|
|
ctx = task_ctx(current); |
|
AA_BUG(!cred_label(bprm->cred)); |
|
AA_BUG(!ctx); |
|
|
|
label = aa_get_newest_label(cred_label(bprm->cred)); |
|
|
|
/* |
|
* Detect no new privs being set, and store the label it |
|
* occurred under. Ideally this would happen when nnp |
|
* is set but there isn't a good way to do that yet. |
|
* |
|
* Testing for unconfined must be done before the subset test |
|
*/ |
|
if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) && !unconfined(label) && |
|
!ctx->nnp) |
|
ctx->nnp = aa_get_label(label); |
|
|
|
/* buffer freed below, name is pointer into buffer */ |
|
buffer = aa_get_buffer(false); |
|
if (!buffer) { |
|
error = -ENOMEM; |
|
goto done; |
|
} |
|
|
|
/* Test for onexec first as onexec override other x transitions. */ |
|
if (ctx->onexec) |
|
new = handle_onexec(label, ctx->onexec, ctx->token, |
|
bprm, buffer, &cond, &unsafe); |
|
else |
|
new = fn_label_build(label, profile, GFP_KERNEL, |
|
profile_transition(profile, bprm, buffer, |
|
&cond, &unsafe)); |
|
|
|
AA_BUG(!new); |
|
if (IS_ERR(new)) { |
|
error = PTR_ERR(new); |
|
goto done; |
|
} else if (!new) { |
|
error = -ENOMEM; |
|
goto done; |
|
} |
|
|
|
/* Policy has specified a domain transitions. If no_new_privs and |
|
* confined ensure the transition is to confinement that is subset |
|
* of the confinement when the task entered no new privs. |
|
* |
|
* NOTE: Domain transitions from unconfined and to stacked |
|
* subsets are allowed even when no_new_privs is set because this |
|
* aways results in a further reduction of permissions. |
|
*/ |
|
if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) && |
|
!unconfined(label) && |
|
!aa_label_is_unconfined_subset(new, ctx->nnp)) { |
|
error = -EPERM; |
|
info = "no new privs"; |
|
goto audit; |
|
} |
|
|
|
if (bprm->unsafe & LSM_UNSAFE_SHARE) { |
|
/* FIXME: currently don't mediate shared state */ |
|
; |
|
} |
|
|
|
if (bprm->unsafe & (LSM_UNSAFE_PTRACE)) { |
|
/* TODO: test needs to be profile of label to new */ |
|
error = may_change_ptraced_domain(new, &info); |
|
if (error) |
|
goto audit; |
|
} |
|
|
|
if (unsafe) { |
|
if (DEBUG_ON) { |
|
dbg_printk("scrubbing environment variables for %s " |
|
"label=", bprm->filename); |
|
aa_label_printk(new, GFP_KERNEL); |
|
dbg_printk("\n"); |
|
} |
|
bprm->secureexec = 1; |
|
} |
|
|
|
if (label->proxy != new->proxy) { |
|
/* when transitioning clear unsafe personality bits */ |
|
if (DEBUG_ON) { |
|
dbg_printk("apparmor: clearing unsafe personality " |
|
"bits. %s label=", bprm->filename); |
|
aa_label_printk(new, GFP_KERNEL); |
|
dbg_printk("\n"); |
|
} |
|
bprm->per_clear |= PER_CLEAR_ON_SETID; |
|
} |
|
aa_put_label(cred_label(bprm->cred)); |
|
/* transfer reference, released when cred is freed */ |
|
set_cred_label(bprm->cred, new); |
|
|
|
done: |
|
aa_put_label(label); |
|
aa_put_buffer(buffer); |
|
|
|
return error; |
|
|
|
audit: |
|
error = fn_for_each(label, profile, |
|
aa_audit_file(profile, &nullperms, OP_EXEC, MAY_EXEC, |
|
bprm->filename, NULL, new, |
|
i_uid, info, error)); |
|
aa_put_label(new); |
|
goto done; |
|
} |
|
|
|
/* |
|
* Functions for self directed profile change |
|
*/ |
|
|
|
|
|
/* helper fn for change_hat |
|
* |
|
* Returns: label for hat transition OR ERR_PTR. Does NOT return NULL |
|
*/ |
|
static struct aa_label *build_change_hat(struct aa_profile *profile, |
|
const char *name, bool sibling) |
|
{ |
|
struct aa_profile *root, *hat = NULL; |
|
const char *info = NULL; |
|
int error = 0; |
|
|
|
if (sibling && PROFILE_IS_HAT(profile)) { |
|
root = aa_get_profile_rcu(&profile->parent); |
|
} else if (!sibling && !PROFILE_IS_HAT(profile)) { |
|
root = aa_get_profile(profile); |
|
} else { |
|
info = "conflicting target types"; |
|
error = -EPERM; |
|
goto audit; |
|
} |
|
|
|
hat = aa_find_child(root, name); |
|
if (!hat) { |
|
error = -ENOENT; |
|
if (COMPLAIN_MODE(profile)) { |
|
hat = aa_new_null_profile(profile, true, name, |
|
GFP_KERNEL); |
|
if (!hat) { |
|
info = "failed null profile create"; |
|
error = -ENOMEM; |
|
} |
|
} |
|
} |
|
aa_put_profile(root); |
|
|
|
audit: |
|
aa_audit_file(profile, &nullperms, OP_CHANGE_HAT, AA_MAY_CHANGEHAT, |
|
name, hat ? hat->base.hname : NULL, |
|
hat ? &hat->label : NULL, GLOBAL_ROOT_UID, info, |
|
error); |
|
if (!hat || (error && error != -ENOENT)) |
|
return ERR_PTR(error); |
|
/* if hat && error - complain mode, already audited and we adjust for |
|
* complain mode allow by returning hat->label |
|
*/ |
|
return &hat->label; |
|
} |
|
|
|
/* helper fn for changing into a hat |
|
* |
|
* Returns: label for hat transition or ERR_PTR. Does not return NULL |
|
*/ |
|
static struct aa_label *change_hat(struct aa_label *label, const char *hats[], |
|
int count, int flags) |
|
{ |
|
struct aa_profile *profile, *root, *hat = NULL; |
|
struct aa_label *new; |
|
struct label_it it; |
|
bool sibling = false; |
|
const char *name, *info = NULL; |
|
int i, error; |
|
|
|
AA_BUG(!label); |
|
AA_BUG(!hats); |
|
AA_BUG(count < 1); |
|
|
|
if (PROFILE_IS_HAT(labels_profile(label))) |
|
sibling = true; |
|
|
|
/*find first matching hat */ |
|
for (i = 0; i < count && !hat; i++) { |
|
name = hats[i]; |
|
label_for_each_in_ns(it, labels_ns(label), label, profile) { |
|
if (sibling && PROFILE_IS_HAT(profile)) { |
|
root = aa_get_profile_rcu(&profile->parent); |
|
} else if (!sibling && !PROFILE_IS_HAT(profile)) { |
|
root = aa_get_profile(profile); |
|
} else { /* conflicting change type */ |
|
info = "conflicting targets types"; |
|
error = -EPERM; |
|
goto fail; |
|
} |
|
hat = aa_find_child(root, name); |
|
aa_put_profile(root); |
|
if (!hat) { |
|
if (!COMPLAIN_MODE(profile)) |
|
goto outer_continue; |
|
/* complain mode succeed as if hat */ |
|
} else if (!PROFILE_IS_HAT(hat)) { |
|
info = "target not hat"; |
|
error = -EPERM; |
|
aa_put_profile(hat); |
|
goto fail; |
|
} |
|
aa_put_profile(hat); |
|
} |
|
/* found a hat for all profiles in ns */ |
|
goto build; |
|
outer_continue: |
|
; |
|
} |
|
/* no hats that match, find appropriate error |
|
* |
|
* In complain mode audit of the failure is based off of the first |
|
* hat supplied. This is done due how userspace interacts with |
|
* change_hat. |
|
*/ |
|
name = NULL; |
|
label_for_each_in_ns(it, labels_ns(label), label, profile) { |
|
if (!list_empty(&profile->base.profiles)) { |
|
info = "hat not found"; |
|
error = -ENOENT; |
|
goto fail; |
|
} |
|
} |
|
info = "no hats defined"; |
|
error = -ECHILD; |
|
|
|
fail: |
|
label_for_each_in_ns(it, labels_ns(label), label, profile) { |
|
/* |
|
* no target as it has failed to be found or built |
|
* |
|
* change_hat uses probing and should not log failures |
|
* related to missing hats |
|
*/ |
|
/* TODO: get rid of GLOBAL_ROOT_UID */ |
|
if (count > 1 || COMPLAIN_MODE(profile)) { |
|
aa_audit_file(profile, &nullperms, OP_CHANGE_HAT, |
|
AA_MAY_CHANGEHAT, name, NULL, NULL, |
|
GLOBAL_ROOT_UID, info, error); |
|
} |
|
} |
|
return ERR_PTR(error); |
|
|
|
build: |
|
new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
|
build_change_hat(profile, name, sibling), |
|
aa_get_label(&profile->label)); |
|
if (!new) { |
|
info = "label build failed"; |
|
error = -ENOMEM; |
|
goto fail; |
|
} /* else if (IS_ERR) build_change_hat has logged error so return new */ |
|
|
|
return new; |
|
} |
|
|
|
/** |
|
* 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 |
|
* @flags: flags affecting behavior of the change |
|
* |
|
* Returns %0 on success, error otherwise. |
|
* |
|
* 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. |
|
* |
|
* change_hat only applies to profiles in the current ns, and each profile |
|
* in the ns must make the same transition otherwise change_hat will fail. |
|
*/ |
|
int aa_change_hat(const char *hats[], int count, u64 token, int flags) |
|
{ |
|
const struct cred *cred; |
|
struct aa_task_ctx *ctx = task_ctx(current); |
|
struct aa_label *label, *previous, *new = NULL, *target = NULL; |
|
struct aa_profile *profile; |
|
struct aa_perms perms = {}; |
|
const char *info = NULL; |
|
int error = 0; |
|
|
|
/* released below */ |
|
cred = get_current_cred(); |
|
label = aa_get_newest_cred_label(cred); |
|
previous = aa_get_newest_label(ctx->previous); |
|
|
|
/* |
|
* Detect no new privs being set, and store the label it |
|
* occurred under. Ideally this would happen when nnp |
|
* is set but there isn't a good way to do that yet. |
|
* |
|
* Testing for unconfined must be done before the subset test |
|
*/ |
|
if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp) |
|
ctx->nnp = aa_get_label(label); |
|
|
|
if (unconfined(label)) { |
|
info = "unconfined can not change_hat"; |
|
error = -EPERM; |
|
goto fail; |
|
} |
|
|
|
if (count) { |
|
new = change_hat(label, hats, count, flags); |
|
AA_BUG(!new); |
|
if (IS_ERR(new)) { |
|
error = PTR_ERR(new); |
|
new = NULL; |
|
/* already audited */ |
|
goto out; |
|
} |
|
|
|
error = may_change_ptraced_domain(new, &info); |
|
if (error) |
|
goto fail; |
|
|
|
/* |
|
* no new privs prevents domain transitions that would |
|
* reduce restrictions. |
|
*/ |
|
if (task_no_new_privs(current) && !unconfined(label) && |
|
!aa_label_is_unconfined_subset(new, ctx->nnp)) { |
|
/* not an apparmor denial per se, so don't log it */ |
|
AA_DEBUG("no_new_privs - change_hat denied"); |
|
error = -EPERM; |
|
goto out; |
|
} |
|
|
|
if (flags & AA_CHANGE_TEST) |
|
goto out; |
|
|
|
target = new; |
|
error = aa_set_current_hat(new, token); |
|
if (error == -EACCES) |
|
/* kill task in case of brute force attacks */ |
|
goto kill; |
|
} else if (previous && !(flags & AA_CHANGE_TEST)) { |
|
/* |
|
* no new privs prevents domain transitions that would |
|
* reduce restrictions. |
|
*/ |
|
if (task_no_new_privs(current) && !unconfined(label) && |
|
!aa_label_is_unconfined_subset(previous, ctx->nnp)) { |
|
/* not an apparmor denial per se, so don't log it */ |
|
AA_DEBUG("no_new_privs - change_hat denied"); |
|
error = -EPERM; |
|
goto out; |
|
} |
|
|
|
/* Return to saved label. Kill task if restore fails |
|
* to avoid brute force attacks |
|
*/ |
|
target = previous; |
|
error = aa_restore_previous_label(token); |
|
if (error) { |
|
if (error == -EACCES) |
|
goto kill; |
|
goto fail; |
|
} |
|
} /* else ignore @flags && restores when there is no saved profile */ |
|
|
|
out: |
|
aa_put_label(new); |
|
aa_put_label(previous); |
|
aa_put_label(label); |
|
put_cred(cred); |
|
|
|
return error; |
|
|
|
kill: |
|
info = "failed token match"; |
|
perms.kill = AA_MAY_CHANGEHAT; |
|
|
|
fail: |
|
fn_for_each_in_ns(label, profile, |
|
aa_audit_file(profile, &perms, OP_CHANGE_HAT, |
|
AA_MAY_CHANGEHAT, NULL, NULL, target, |
|
GLOBAL_ROOT_UID, info, error)); |
|
|
|
goto out; |
|
} |
|
|
|
|
|
static int change_profile_perms_wrapper(const char *op, const char *name, |
|
struct aa_profile *profile, |
|
struct aa_label *target, bool stack, |
|
u32 request, struct aa_perms *perms) |
|
{ |
|
const char *info = NULL; |
|
int error = 0; |
|
|
|
if (!error) |
|
error = change_profile_perms(profile, target, stack, request, |
|
profile->file.start, perms); |
|
if (error) |
|
error = aa_audit_file(profile, perms, op, request, name, |
|
NULL, target, GLOBAL_ROOT_UID, info, |
|
error); |
|
|
|
return error; |
|
} |
|
|
|
/** |
|
* aa_change_profile - perform a one-way profile transition |
|
* @fqname: name of profile may include namespace (NOT NULL) |
|
* @onexec: whether this transition is to take place immediately or at exec |
|
* @flags: flags affecting change behavior |
|
* |
|
* 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 *fqname, int flags) |
|
{ |
|
struct aa_label *label, *new = NULL, *target = NULL; |
|
struct aa_profile *profile; |
|
struct aa_perms perms = {}; |
|
const char *info = NULL; |
|
const char *auditname = fqname; /* retain leading & if stack */ |
|
bool stack = flags & AA_CHANGE_STACK; |
|
struct aa_task_ctx *ctx = task_ctx(current); |
|
int error = 0; |
|
char *op; |
|
u32 request; |
|
|
|
label = aa_get_current_label(); |
|
|
|
/* |
|
* Detect no new privs being set, and store the label it |
|
* occurred under. Ideally this would happen when nnp |
|
* is set but there isn't a good way to do that yet. |
|
* |
|
* Testing for unconfined must be done before the subset test |
|
*/ |
|
if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp) |
|
ctx->nnp = aa_get_label(label); |
|
|
|
if (!fqname || !*fqname) { |
|
aa_put_label(label); |
|
AA_DEBUG("no profile name"); |
|
return -EINVAL; |
|
} |
|
|
|
if (flags & AA_CHANGE_ONEXEC) { |
|
request = AA_MAY_ONEXEC; |
|
if (stack) |
|
op = OP_STACK_ONEXEC; |
|
else |
|
op = OP_CHANGE_ONEXEC; |
|
} else { |
|
request = AA_MAY_CHANGE_PROFILE; |
|
if (stack) |
|
op = OP_STACK; |
|
else |
|
op = OP_CHANGE_PROFILE; |
|
} |
|
|
|
if (*fqname == '&') { |
|
stack = true; |
|
/* don't have label_parse() do stacking */ |
|
fqname++; |
|
} |
|
target = aa_label_parse(label, fqname, GFP_KERNEL, true, false); |
|
if (IS_ERR(target)) { |
|
struct aa_profile *tprofile; |
|
|
|
info = "label not found"; |
|
error = PTR_ERR(target); |
|
target = NULL; |
|
/* |
|
* TODO: fixme using labels_profile is not right - do profile |
|
* per complain profile |
|
*/ |
|
if ((flags & AA_CHANGE_TEST) || |
|
!COMPLAIN_MODE(labels_profile(label))) |
|
goto audit; |
|
/* released below */ |
|
tprofile = aa_new_null_profile(labels_profile(label), false, |
|
fqname, GFP_KERNEL); |
|
if (!tprofile) { |
|
info = "failed null profile create"; |
|
error = -ENOMEM; |
|
goto audit; |
|
} |
|
target = &tprofile->label; |
|
goto check; |
|
} |
|
|
|
/* |
|
* self directed transitions only apply to current policy ns |
|
* TODO: currently requiring perms for stacking and straight change |
|
* stacking doesn't strictly need this. Determine how much |
|
* we want to loosen this restriction for stacking |
|
* |
|
* if (!stack) { |
|
*/ |
|
error = fn_for_each_in_ns(label, profile, |
|
change_profile_perms_wrapper(op, auditname, |
|
profile, target, stack, |
|
request, &perms)); |
|
if (error) |
|
/* auditing done in change_profile_perms_wrapper */ |
|
goto out; |
|
|
|
/* } */ |
|
|
|
check: |
|
/* check if tracing task is allowed to trace target domain */ |
|
error = may_change_ptraced_domain(target, &info); |
|
if (error && !fn_for_each_in_ns(label, profile, |
|
COMPLAIN_MODE(profile))) |
|
goto audit; |
|
|
|
/* TODO: add permission check to allow this |
|
* if ((flags & AA_CHANGE_ONEXEC) && !current_is_single_threaded()) { |
|
* info = "not a single threaded task"; |
|
* error = -EACCES; |
|
* goto audit; |
|
* } |
|
*/ |
|
if (flags & AA_CHANGE_TEST) |
|
goto out; |
|
|
|
/* stacking is always a subset, so only check the nonstack case */ |
|
if (!stack) { |
|
new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
|
aa_get_label(target), |
|
aa_get_label(&profile->label)); |
|
/* |
|
* no new privs prevents domain transitions that would |
|
* reduce restrictions. |
|
*/ |
|
if (task_no_new_privs(current) && !unconfined(label) && |
|
!aa_label_is_unconfined_subset(new, ctx->nnp)) { |
|
/* not an apparmor denial per se, so don't log it */ |
|
AA_DEBUG("no_new_privs - change_hat denied"); |
|
error = -EPERM; |
|
goto out; |
|
} |
|
} |
|
|
|
if (!(flags & AA_CHANGE_ONEXEC)) { |
|
/* only transition profiles in the current ns */ |
|
if (stack) |
|
new = aa_label_merge(label, target, GFP_KERNEL); |
|
if (IS_ERR_OR_NULL(new)) { |
|
info = "failed to build target label"; |
|
if (!new) |
|
error = -ENOMEM; |
|
else |
|
error = PTR_ERR(new); |
|
new = NULL; |
|
perms.allow = 0; |
|
goto audit; |
|
} |
|
error = aa_replace_current_label(new); |
|
} else { |
|
if (new) { |
|
aa_put_label(new); |
|
new = NULL; |
|
} |
|
|
|
/* full transition will be built in exec path */ |
|
error = aa_set_current_onexec(target, stack); |
|
} |
|
|
|
audit: |
|
error = fn_for_each_in_ns(label, profile, |
|
aa_audit_file(profile, &perms, op, request, auditname, |
|
NULL, new ? new : target, |
|
GLOBAL_ROOT_UID, info, error)); |
|
|
|
out: |
|
aa_put_label(new); |
|
aa_put_label(target); |
|
aa_put_label(label); |
|
|
|
return error; |
|
}
|
|
|