diff options
| -rw-r--r-- | security/apparmor/domain.c | 80 |
1 files changed, 54 insertions, 26 deletions
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index 4154964cdac5..bb2216f17bd9 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -875,6 +875,52 @@ static struct aa_label *label_merge_wrap(struct aa_label *a, struct aa_label *b, return label; } +static bool is_profile_priv_restricted_to_stack(const struct cred *subj_cred, + struct aa_profile *profile) +{ + if (profile_unconfined(profile) && profile == profile->ns->unconfined && + aa_unprivileged_unconfined_restricted && + /* cap_capable returns false (0) if true, hence true here means + * doesn't have capability and the stack will be restricted + */ + cap_capable(current_cred(), &init_user_ns, CAP_MAC_OVERRIDE, + CAP_OPT_NOAUDIT)) + return true; + return false; +} + +static const char *stack_msg = "change_profile unprivileged unconfined converted to stacking"; + +static struct aa_label *priv_restricted_transition(const struct cred *subj_cred, + struct aa_profile *profile, + const char *op, u32 request, + const char *name, + struct aa_label *transition, + gfp_t gfp) +{ + if (!is_profile_priv_restricted_to_stack(subj_cred, profile)) + return aa_get_newest_label(transition); + + /* transition allowed but only via stack */ + struct aa_label *target = label_merge_wrap(&profile->label, + transition, gfp); + if (IS_ERR_OR_NULL(target)) + return target; + + /* doing this here is less than optimal but good enough until the + * fs mediation rework lands + */ + struct aa_perms perms = { + .allow = request, + .audit = request, + }; + aa_audit_file(subj_cred, profile, &perms, op, + request, name, NULL, target, + subj_cred->euid, stack_msg, 0); + + return target; +} + static struct aa_label *handle_onexec(const struct cred *subj_cred, struct aa_label *label, struct aa_label *onexec, bool stack, @@ -903,7 +949,10 @@ static struct aa_label *handle_onexec(const struct cred *subj_cred, new = fn_label_build_in_scope(label, profile, GFP_KERNEL, stack ? label_merge_wrap(&profile->label, onexec, GFP_KERNEL) - : aa_get_newest_label(onexec), + : priv_restricted_transition(subj_cred, profile, + OP_CHANGE_ONEXEC, AA_MAY_ONEXEC, + bprm->filename, onexec, + GFP_KERNEL), profile_transition(subj_cred, profile, bprm, buffer, cond, unsafe)); AA_BUG(!new); @@ -1407,8 +1456,6 @@ static int change_profile_perms_wrapper(const char *op, const char *name, return error; } -static const char *stack_msg = "change_profile unprivileged unconfined converted to stacking"; - /** * aa_change_profile - perform a one-way profile transition * @fqname: name of profile may include namespace (NOT NULL) @@ -1468,28 +1515,6 @@ int aa_change_profile(const char *fqname, int flags) op = OP_CHANGE_PROFILE; } - /* This should move to a per profile test. Requires pushing build - * into callback - */ - if (!stack && unconfined(label) && - label == &labels_ns(label)->unconfined->label && - aa_unprivileged_unconfined_restricted && - /* TODO: refactor so this check is a fn */ - cap_capable(current_cred(), &init_user_ns, CAP_MAC_OVERRIDE, - CAP_OPT_NOAUDIT)) { - /* regardless of the request in this case apparmor - * stacks against unconfined so admin set policy can't be - * by-passed - */ - stack = true; - perms.audit = request; - (void) fn_for_each_in_scope(label, profile, - aa_audit_file(subj_cred, profile, &perms, op, - request, auditname, NULL, target, - GLOBAL_ROOT_UID, stack_msg, 0)); - perms.audit = 0; - } - if (*fqname == '&') { stack = true; /* don't have label_parse() do stacking */ @@ -1560,7 +1585,10 @@ check: /* stacking is always a subset, so only check the nonstack case */ if (!stack) { new = fn_label_build_in_scope(label, profile, GFP_KERNEL, - aa_get_label(target), + priv_restricted_transition(subj_cred, profile, + op, request, + auditname, target, + GFP_KERNEL), aa_get_label(&profile->label)); AA_BUG(!new); if (IS_ERR(new)) |