diff options
Diffstat (limited to 'security/selinux/ss/services.c')
| -rw-r--r-- | security/selinux/ss/services.c | 1528 |
1 files changed, 903 insertions, 625 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 216ce602a2b5..64a6a37dc36d 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -46,8 +46,8 @@ #include <linux/in.h> #include <linux/sched.h> #include <linux/audit.h> -#include <linux/mutex.h> #include <linux/vmalloc.h> +#include <linux/lsm_hooks.h> #include <net/netlabel.h> #include "flask.h" @@ -65,25 +65,19 @@ #include "xfrm.h" #include "ebitmap.h" #include "audit.h" +#include "policycap_names.h" +#include "ima.h" -/* Policy capability names */ -const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = { - "network_peer_controls", - "open_perms", - "extended_socket_class", - "always_check_network", - "cgroup_seclabel", - "nnp_nosuid_transition" +struct convert_context_args { + struct selinux_state *state; + struct policydb *oldp; + struct policydb *newp; }; -static struct selinux_ss selinux_ss; - -void selinux_ss_init(struct selinux_ss **ss) -{ - rwlock_init(&selinux_ss.policy_rwlock); - mutex_init(&selinux_ss.status_lock); - *ss = &selinux_ss; -} +struct selinux_policy_convert_data { + struct convert_context_args args; + struct sidtab_convert_params sidtab_params; +}; /* Forward declaration. */ static int context_struct_to_string(struct policydb *policydb, @@ -105,7 +99,7 @@ static void context_struct_compute_av(struct policydb *policydb, struct extended_perms *xperms); static int selinux_set_mapping(struct policydb *pol, - struct security_class_mapping *map, + const struct security_class_mapping *map, struct selinux_map *out_map) { u16 i, j; @@ -127,7 +121,7 @@ static int selinux_set_mapping(struct policydb *pol, /* Store the raw class and permission values */ j = 0; while (map[j].name) { - struct security_class_mapping *p_in = map + (j++); + const struct security_class_mapping *p_in = map + (j++); struct selinux_mapping *p_out = out_map->mapping + j; /* An empty class string skips ahead */ @@ -249,9 +243,17 @@ static void map_decision(struct selinux_map *map, int security_mls_enabled(struct selinux_state *state) { - struct policydb *p = &state->ss->policydb; + int mls_enabled; + struct selinux_policy *policy; + + if (!selinux_initialized(state)) + return 0; - return p->mls_enabled; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + mls_enabled = policy->policydb.mls_enabled; + rcu_read_unlock(); + return mls_enabled; } /* @@ -356,27 +358,27 @@ static int constraint_expr_eval(struct policydb *policydb, l2 = &(tcontext->range.level[1]); goto mls_ops; mls_ops: - switch (e->op) { - case CEXPR_EQ: - s[++sp] = mls_level_eq(l1, l2); - continue; - case CEXPR_NEQ: - s[++sp] = !mls_level_eq(l1, l2); - continue; - case CEXPR_DOM: - s[++sp] = mls_level_dom(l1, l2); - continue; - case CEXPR_DOMBY: - s[++sp] = mls_level_dom(l2, l1); - continue; - case CEXPR_INCOMP: - s[++sp] = mls_level_incomp(l2, l1); - continue; - default: - BUG(); - return 0; - } - break; + switch (e->op) { + case CEXPR_EQ: + s[++sp] = mls_level_eq(l1, l2); + continue; + case CEXPR_NEQ: + s[++sp] = !mls_level_eq(l1, l2); + continue; + case CEXPR_DOM: + s[++sp] = mls_level_dom(l1, l2); + continue; + case CEXPR_DOMBY: + s[++sp] = mls_level_dom(l2, l1); + continue; + case CEXPR_INCOMP: + s[++sp] = mls_level_incomp(l2, l1); + continue; + default: + BUG(); + return 0; + } + break; default: BUG(); return 0; @@ -483,11 +485,11 @@ static void security_dump_masked_av(struct policydb *policydb, /* init permission_names */ if (common_dat && - hashtab_map(common_dat->permissions.table, + hashtab_map(&common_dat->permissions.table, dump_masked_av_helper, permission_names) < 0) goto out; - if (hashtab_map(tclass_dat->permissions.table, + if (hashtab_map(&tclass_dat->permissions.table, dump_masked_av_helper, permission_names) < 0) goto out; @@ -527,8 +529,6 @@ out: /* release scontext/tcontext */ kfree(tcontext_name); kfree(scontext_name); - - return; } /* @@ -607,9 +607,7 @@ void services_compute_xperms_drivers( node->datum.u.xperms->driver); } - /* If no ioctl commands are allowed, ignore auditallow and auditdeny */ - if (node->key.specified & AVTAB_XPERMS_ALLOWED) - xperms->len = 1; + xperms->len = 1; } /* @@ -722,13 +720,14 @@ static void context_struct_compute_av(struct policydb *policydb, } static int security_validtrans_handle_fail(struct selinux_state *state, - struct sidtab_entry *oentry, - struct sidtab_entry *nentry, - struct sidtab_entry *tentry, - u16 tclass) -{ - struct policydb *p = &state->ss->policydb; - struct sidtab *sidtab = state->ss->sidtab; + struct selinux_policy *policy, + struct sidtab_entry *oentry, + struct sidtab_entry *nentry, + struct sidtab_entry *tentry, + u16 tclass) +{ + struct policydb *p = &policy->policydb; + struct sidtab *sidtab = policy->sidtab; char *o = NULL, *n = NULL, *t = NULL; u32 olen, nlen, tlen; @@ -756,6 +755,7 @@ static int security_compute_validatetrans(struct selinux_state *state, u32 oldsid, u32 newsid, u32 tasksid, u16 orig_tclass, bool user) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct sidtab_entry *oentry; @@ -770,13 +770,14 @@ static int security_compute_validatetrans(struct selinux_state *state, if (!selinux_initialized(state)) return 0; - read_lock(&state->ss->policy_rwlock); + rcu_read_lock(); - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; if (!user) - tclass = unmap_class(&state->ss->map, orig_tclass); + tclass = unmap_class(&policy->map, orig_tclass); else tclass = orig_tclass; @@ -819,17 +820,18 @@ static int security_compute_validatetrans(struct selinux_state *state, rc = -EPERM; else rc = security_validtrans_handle_fail(state, - oentry, - nentry, - tentry, - tclass); + policy, + oentry, + nentry, + tentry, + tclass); goto out; } constraint = constraint->next; } out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } @@ -855,12 +857,14 @@ int security_validate_transition(struct selinux_state *state, * It returns 0, if @newsid is bounded by @oldsid. * Otherwise, it returns error code. * + * @state: SELinux state * @oldsid : current security identifier * @newsid : destinated security identifier */ int security_bounded_transition(struct selinux_state *state, u32 old_sid, u32 new_sid) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct sidtab_entry *old_entry, *new_entry; @@ -871,10 +875,10 @@ int security_bounded_transition(struct selinux_state *state, if (!selinux_initialized(state)) return 0; - read_lock(&state->ss->policy_rwlock); - - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; rc = -EINVAL; old_entry = sidtab_search_entry(sidtab, old_sid); @@ -935,17 +939,20 @@ int security_bounded_transition(struct selinux_state *state, kfree(old_name); } out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } -static void avd_init(struct selinux_state *state, struct av_decision *avd) +static void avd_init(struct selinux_policy *policy, struct av_decision *avd) { avd->allowed = 0; avd->auditallow = 0; avd->auditdeny = 0xffffffff; - avd->seqno = state->ss->latest_granting; + if (policy) + avd->seqno = policy->latest_granting; + else + avd->seqno = 0; avd->flags = 0; } @@ -1010,6 +1017,7 @@ void security_compute_xperms_decision(struct selinux_state *state, u8 driver, struct extended_perms_decision *xpermd) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; u16 tclass; @@ -1026,12 +1034,13 @@ void security_compute_xperms_decision(struct selinux_state *state, memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p)); memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p)); - read_lock(&state->ss->policy_rwlock); + rcu_read_lock(); if (!selinux_initialized(state)) goto allow; - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1047,7 +1056,7 @@ void security_compute_xperms_decision(struct selinux_state *state, goto out; } - tclass = unmap_class(&state->ss->map, orig_tclass); + tclass = unmap_class(&policy->map, orig_tclass); if (unlikely(orig_tclass && !tclass)) { if (policydb->allow_unknown) goto allow; @@ -1079,7 +1088,7 @@ void security_compute_xperms_decision(struct selinux_state *state, } } out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return; allow: memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); @@ -1088,9 +1097,10 @@ allow: /** * security_compute_av - Compute access vector decisions. + * @state: SELinux state * @ssid: source security identifier * @tsid: target security identifier - * @tclass: target security class + * @orig_tclass: target security class * @avd: access vector decisions * @xperms: extended permissions * @@ -1104,19 +1114,21 @@ void security_compute_av(struct selinux_state *state, struct av_decision *avd, struct extended_perms *xperms) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; u16 tclass; struct context *scontext = NULL, *tcontext = NULL; - read_lock(&state->ss->policy_rwlock); - avd_init(state, avd); + rcu_read_lock(); + policy = rcu_dereference(state->policy); + avd_init(policy, avd); xperms->len = 0; if (!selinux_initialized(state)) goto allow; - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + policydb = &policy->policydb; + sidtab = policy->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1136,7 +1148,7 @@ void security_compute_av(struct selinux_state *state, goto out; } - tclass = unmap_class(&state->ss->map, orig_tclass); + tclass = unmap_class(&policy->map, orig_tclass); if (unlikely(orig_tclass && !tclass)) { if (policydb->allow_unknown) goto allow; @@ -1144,10 +1156,10 @@ void security_compute_av(struct selinux_state *state, } context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, xperms); - map_decision(&state->ss->map, orig_tclass, avd, + map_decision(&policy->map, orig_tclass, avd, policydb->allow_unknown); out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return; allow: avd->allowed = 0xffffffff; @@ -1160,17 +1172,19 @@ void security_compute_av_user(struct selinux_state *state, u16 tclass, struct av_decision *avd) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct context *scontext = NULL, *tcontext = NULL; - read_lock(&state->ss->policy_rwlock); - avd_init(state, avd); + rcu_read_lock(); + policy = rcu_dereference(state->policy); + avd_init(policy, avd); if (!selinux_initialized(state)) goto allow; - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + policydb = &policy->policydb; + sidtab = policy->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1199,7 +1213,7 @@ void security_compute_av_user(struct selinux_state *state, context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, NULL); out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return; allow: avd->allowed = 0xffffffff; @@ -1284,6 +1298,7 @@ static int sidtab_entry_to_string(struct policydb *p, int security_sidtab_hash_stats(struct selinux_state *state, char *page) { + struct selinux_policy *policy; int rc; if (!selinux_initialized(state)) { @@ -1292,9 +1307,10 @@ int security_sidtab_hash_stats(struct selinux_state *state, char *page) return -EINVAL; } - read_lock(&state->ss->policy_rwlock); - rc = sidtab_hash_stats(state->ss->sidtab, page); - read_unlock(&state->ss->policy_rwlock); + rcu_read_lock(); + policy = rcu_dereference(state->policy); + rc = sidtab_hash_stats(policy->sidtab, page); + rcu_read_unlock(); return rc; } @@ -1311,6 +1327,7 @@ static int security_sid_to_context_core(struct selinux_state *state, u32 *scontext_len, int force, int only_invalid) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct sidtab_entry *entry; @@ -1323,27 +1340,27 @@ static int security_sid_to_context_core(struct selinux_state *state, if (!selinux_initialized(state)) { if (sid <= SECINITSID_NUM) { char *scontextp; + const char *s = initial_sid_to_string[sid]; - *scontext_len = strlen(initial_sid_to_string[sid]) + 1; + if (!s) + return -EINVAL; + *scontext_len = strlen(s) + 1; if (!scontext) - goto out; - scontextp = kmemdup(initial_sid_to_string[sid], - *scontext_len, GFP_ATOMIC); - if (!scontextp) { - rc = -ENOMEM; - goto out; - } + return 0; + scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC); + if (!scontextp) + return -ENOMEM; *scontext = scontextp; - goto out; + return 0; } pr_err("SELinux: %s: called before initial " "load_policy on unknown SID %d\n", __func__, sid); - rc = -EINVAL; - goto out; + return -EINVAL; } - read_lock(&state->ss->policy_rwlock); - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; if (force) entry = sidtab_search_entry_force(sidtab, sid); @@ -1362,14 +1379,14 @@ static int security_sid_to_context_core(struct selinux_state *state, scontext_len); out_unlock: - read_unlock(&state->ss->policy_rwlock); -out: + rcu_read_unlock(); return rc; } /** * security_sid_to_context - Obtain a context for a given SID. + * @state: SELinux state * @sid: security identifier, SID * @scontext: security context * @scontext_len: length in bytes @@ -1395,6 +1412,7 @@ int security_sid_to_context_force(struct selinux_state *state, u32 sid, /** * security_sid_to_context_inval - Obtain a context for a given SID if it * is invalid. + * @state: SELinux state * @sid: security identifier, SID * @scontext: security context * @scontext_len: length in bytes @@ -1432,7 +1450,7 @@ static int string_to_context_struct(struct policydb *pol, /* Parse the security context. */ rc = -EINVAL; - scontextp = (char *) scontext; + scontextp = scontext; /* Extract the user. */ p = scontextp; @@ -1444,7 +1462,7 @@ static int string_to_context_struct(struct policydb *pol, *p++ = 0; - usrdatum = hashtab_search(pol->p_users.table, scontextp); + usrdatum = symtab_search(&pol->p_users, scontextp); if (!usrdatum) goto out; @@ -1460,7 +1478,7 @@ static int string_to_context_struct(struct policydb *pol, *p++ = 0; - role = hashtab_search(pol->p_roles.table, scontextp); + role = symtab_search(&pol->p_roles, scontextp); if (!role) goto out; ctx->role = role->value; @@ -1472,7 +1490,7 @@ static int string_to_context_struct(struct policydb *pol, oldc = *p; *p++ = 0; - typdatum = hashtab_search(pol->p_types.table, scontextp); + typdatum = symtab_search(&pol->p_types, scontextp); if (!typdatum || typdatum->attribute) goto out; @@ -1493,47 +1511,12 @@ out: return rc; } -int context_add_hash(struct policydb *policydb, - struct context *context) -{ - int rc; - char *str; - int len; - - if (context->str) { - context->hash = context_compute_hash(context->str); - } else { - rc = context_struct_to_string(policydb, context, - &str, &len); - if (rc) - return rc; - context->hash = context_compute_hash(str); - kfree(str); - } - return 0; -} - -static int context_struct_to_sid(struct selinux_state *state, - struct context *context, u32 *sid) -{ - int rc; - struct sidtab *sidtab = state->ss->sidtab; - struct policydb *policydb = &state->ss->policydb; - - if (!context->hash) { - rc = context_add_hash(policydb, context); - if (rc) - return rc; - } - - return sidtab_context_to_sid(sidtab, context, sid); -} - static int security_context_to_sid_core(struct selinux_state *state, const char *scontext, u32 scontext_len, u32 *sid, u32 def_sid, gfp_t gfp_flags, int force) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; char *scontext2, *str = NULL; @@ -1553,7 +1536,9 @@ static int security_context_to_sid_core(struct selinux_state *state, int i; for (i = 1; i < SECINITSID_NUM; i++) { - if (!strcmp(initial_sid_to_string[i], scontext2)) { + const char *s = initial_sid_to_string[i]; + + if (s && !strcmp(s, scontext2)) { *sid = i; goto out; } @@ -1570,9 +1555,11 @@ static int security_context_to_sid_core(struct selinux_state *state, if (!str) goto out; } - read_lock(&state->ss->policy_rwlock); - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; +retry: + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; rc = string_to_context_struct(policydb, sidtab, scontext2, &context, def_sid); if (rc == -EINVAL && force) { @@ -1581,10 +1568,19 @@ static int security_context_to_sid_core(struct selinux_state *state, str = NULL; } else if (rc) goto out_unlock; - rc = context_struct_to_sid(state, &context, sid); + rc = sidtab_context_to_sid(sidtab, &context, sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + if (context.str) { + str = context.str; + context.str = NULL; + } + context_destroy(&context); + goto retry; + } context_destroy(&context); out_unlock: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); out: kfree(scontext2); kfree(str); @@ -1593,6 +1589,7 @@ out: /** * security_context_to_sid - Obtain a SID for a given security context. + * @state: SELinux state * @scontext: security context * @scontext_len: length in bytes * @sid: security identifier, SID @@ -1622,10 +1619,12 @@ int security_context_str_to_sid(struct selinux_state *state, * security_context_to_sid_default - Obtain a SID for a given security context, * falling back to specified default if needed. * + * @state: SELinux state * @scontext: security context * @scontext_len: length in bytes * @sid: security identifier, SID * @def_sid: default SID to assign on error + * @gfp_flags: the allocator get-free-page (GFP) flags * * Obtains a SID associated with the security context that * has the string representation specified by @scontext. @@ -1654,13 +1653,14 @@ int security_context_to_sid_force(struct selinux_state *state, static int compute_sid_handle_invalid_context( struct selinux_state *state, + struct selinux_policy *policy, struct sidtab_entry *sentry, struct sidtab_entry *tentry, u16 tclass, struct context *newcontext) { - struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = state->ss->sidtab; + struct policydb *policydb = &policy->policydb; + struct sidtab *sidtab = policy->sidtab; char *s = NULL, *t = NULL, *n = NULL; u32 slen, tlen, nlen; struct audit_buffer *ab; @@ -1672,6 +1672,8 @@ static int compute_sid_handle_invalid_context( if (context_struct_to_string(policydb, newcontext, &n, &nlen)) goto out; ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); + if (!ab) + goto out; audit_log_format(ab, "op=security_compute_sid invalid_context="); /* no need to record the NUL with untrusted strings */ @@ -1693,8 +1695,8 @@ static void filename_compute_type(struct policydb *policydb, u32 stype, u32 ttype, u16 tclass, const char *objname) { - struct filename_trans ft; - struct filename_trans_datum *otype; + struct filename_trans_key ft; + struct filename_trans_datum *datum; /* * Most filename trans rules are going to live in specific directories @@ -1704,14 +1706,18 @@ static void filename_compute_type(struct policydb *policydb, if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype)) return; - ft.stype = stype; ft.ttype = ttype; ft.tclass = tclass; ft.name = objname; - otype = hashtab_search(policydb->filename_trans, &ft); - if (otype) - newcontext->type = otype->otype; + datum = policydb_filenametr_search(policydb, &ft); + while (datum) { + if (ebitmap_get_bit(&datum->stypes, stype - 1)) { + newcontext->type = datum->otype; + return; + } + datum = datum->next; + } } static int security_compute_sid(struct selinux_state *state, @@ -1723,12 +1729,12 @@ static int security_compute_sid(struct selinux_state *state, u32 *out_sid, bool kern) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; - struct class_datum *cladatum = NULL; + struct class_datum *cladatum; struct context *scontext, *tcontext, newcontext; struct sidtab_entry *sentry, *tentry; - struct role_trans *roletr = NULL; struct avtab_key avkey; struct avtab_datum *avdatum; struct avtab_node *node; @@ -1748,21 +1754,25 @@ static int security_compute_sid(struct selinux_state *state, goto out; } +retry: + cladatum = NULL; context_init(&newcontext); - read_lock(&state->ss->policy_rwlock); + rcu_read_lock(); + + policy = rcu_dereference(state->policy); if (kern) { - tclass = unmap_class(&state->ss->map, orig_tclass); + tclass = unmap_class(&policy->map, orig_tclass); sock = security_is_socket_class(orig_tclass); } else { tclass = orig_tclass; - sock = security_is_socket_class(map_class(&state->ss->map, + sock = security_is_socket_class(map_class(&policy->map, tclass)); } - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; + policydb = &policy->policydb; + sidtab = policy->sidtab; sentry = sidtab_search_entry(sidtab, ssid); if (!sentry) { @@ -1809,7 +1819,7 @@ static int security_compute_sid(struct selinux_state *state, } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { newcontext.role = tcontext->role; } else { - if ((tclass == policydb->process_class) || (sock == true)) + if ((tclass == policydb->process_class) || sock) newcontext.role = scontext->role; else newcontext.role = OBJECT_R_VAL; @@ -1821,7 +1831,7 @@ static int security_compute_sid(struct selinux_state *state, } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) { newcontext.type = tcontext->type; } else { - if ((tclass == policydb->process_class) || (sock == true)) { + if ((tclass == policydb->process_class) || sock) { /* Use the type of process. */ newcontext.type = scontext->type; } else { @@ -1861,16 +1871,16 @@ static int security_compute_sid(struct selinux_state *state, /* Check for class-specific changes. */ if (specified & AVTAB_TRANSITION) { /* Look for a role transition rule. */ - for (roletr = policydb->role_tr; roletr; - roletr = roletr->next) { - if ((roletr->role == scontext->role) && - (roletr->type == tcontext->type) && - (roletr->tclass == tclass)) { - /* Use the role transition rule. */ - newcontext.role = roletr->new_role; - break; - } - } + struct role_trans_datum *rtd; + struct role_trans_key rtk = { + .role = scontext->role, + .type = tcontext->type, + .tclass = tclass, + }; + + rtd = policydb_roletr_search(policydb, &rtk); + if (rtd) + newcontext.role = rtd->new_role; } /* Set the MLS attributes. @@ -1882,15 +1892,21 @@ static int security_compute_sid(struct selinux_state *state, /* Check the validity of the context. */ if (!policydb_context_isvalid(policydb, &newcontext)) { - rc = compute_sid_handle_invalid_context(state, sentry, tentry, - tclass, &newcontext); + rc = compute_sid_handle_invalid_context(state, policy, sentry, + tentry, tclass, + &newcontext); if (rc) goto out_unlock; } /* Obtain the sid for the context. */ - rc = context_struct_to_sid(state, &newcontext, out_sid); + rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + context_destroy(&newcontext); + goto retry; + } out_unlock: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); context_destroy(&newcontext); out: return rc; @@ -1898,9 +1914,11 @@ out: /** * security_transition_sid - Compute the SID for a new subject/object. + * @state: SELinux state * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class + * @qstr: object name * @out_sid: security identifier for new subject/object * * Compute a SID to use for labeling a new subject or object in the @@ -1929,6 +1947,7 @@ int security_transition_sid_user(struct selinux_state *state, /** * security_member_sid - Compute the SID for member selection. + * @state: SELinux state * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class @@ -1953,6 +1972,7 @@ int security_member_sid(struct selinux_state *state, /** * security_change_sid - Compute the SID for object relabeling. + * @state: SELinux state * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class @@ -1977,9 +1997,9 @@ int security_change_sid(struct selinux_state *state, static inline int convert_context_handle_invalid_context( struct selinux_state *state, + struct policydb *policydb, struct context *context) { - struct policydb *policydb = &state->ss->policydb; char *s; u32 len; @@ -1994,12 +2014,6 @@ static inline int convert_context_handle_invalid_context( return 0; } -struct convert_context_args { - struct selinux_state *state; - struct policydb *oldp; - struct policydb *newp; -}; - /* * Convert the values in the security context * structure `oldc' from the values specified @@ -2008,7 +2022,8 @@ struct convert_context_args { * in `newc'. Verify that the context is valid * under the new policy. */ -static int convert_context(struct context *oldc, struct context *newc, void *p) +static int convert_context(struct context *oldc, struct context *newc, void *p, + gfp_t gfp_flags) { struct convert_context_args *args; struct ocontext *oc; @@ -2022,7 +2037,7 @@ static int convert_context(struct context *oldc, struct context *newc, void *p) args = p; if (oldc->str) { - s = kstrdup(oldc->str, GFP_KERNEL); + s = kstrdup(oldc->str, gfp_flags); if (!s) return -ENOMEM; @@ -2040,7 +2055,6 @@ static int convert_context(struct context *oldc, struct context *newc, void *p) context_init(newc); newc->str = s; newc->len = oldc->len; - newc->hash = oldc->hash; return 0; } kfree(s); @@ -2058,27 +2072,24 @@ static int convert_context(struct context *oldc, struct context *newc, void *p) context_init(newc); /* Convert the user. */ - rc = -EINVAL; - usrdatum = hashtab_search(args->newp->p_users.table, - sym_name(args->oldp, - SYM_USERS, oldc->user - 1)); + usrdatum = symtab_search(&args->newp->p_users, + sym_name(args->oldp, + SYM_USERS, oldc->user - 1)); if (!usrdatum) goto bad; newc->user = usrdatum->value; /* Convert the role. */ - rc = -EINVAL; - role = hashtab_search(args->newp->p_roles.table, - sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); + role = symtab_search(&args->newp->p_roles, + sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); if (!role) goto bad; newc->role = role->value; /* Convert the type. */ - rc = -EINVAL; - typdatum = hashtab_search(args->newp->p_types.table, - sym_name(args->oldp, - SYM_TYPES, oldc->type - 1)); + typdatum = symtab_search(&args->newp->p_types, + sym_name(args->oldp, + SYM_TYPES, oldc->type - 1)); if (!typdatum) goto bad; newc->type = typdatum->value; @@ -2099,7 +2110,6 @@ static int convert_context(struct context *oldc, struct context *newc, void *p) oc = args->newp->ocontexts[OCON_ISID]; while (oc && oc->sid[0] != SECINITSID_UNLABELED) oc = oc->next; - rc = -EINVAL; if (!oc) { pr_err("SELinux: unable to look up" " the initial SIDs list\n"); @@ -2112,15 +2122,13 @@ static int convert_context(struct context *oldc, struct context *newc, void *p) /* Check the validity of the new context. */ if (!policydb_context_isvalid(args->newp, newc)) { - rc = convert_context_handle_invalid_context(args->state, oldc); + rc = convert_context_handle_invalid_context(args->state, + args->oldp, + oldc); if (rc) goto bad; } - rc = context_add_hash(args->newp, newc); - if (rc) - goto bad; - return 0; bad: /* Map old representation to string and save it. */ @@ -2130,20 +2138,23 @@ bad: context_destroy(newc); newc->str = s; newc->len = len; - newc->hash = context_compute_hash(s); pr_info("SELinux: Context %s became invalid (unmapped).\n", newc->str); return 0; } -static void security_load_policycaps(struct selinux_state *state) +static void security_load_policycaps(struct selinux_state *state, + struct selinux_policy *policy) { - struct policydb *p = &state->ss->policydb; + struct policydb *p; unsigned int i; struct ebitmap_node *node; + p = &policy->policydb; + for (i = 0; i < ARRAY_SIZE(state->policycap); i++) - state->policycap[i] = ebitmap_get_bit(&p->policycaps, i); + WRITE_ONCE(state->policycap[i], + ebitmap_get_bit(&p->policycaps, i)); for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++) pr_info("SELinux: policy capability %s=%d\n", @@ -2157,188 +2168,257 @@ static void security_load_policycaps(struct selinux_state *state) } } -static int security_preserve_bools(struct selinux_state *state, - struct policydb *newpolicydb); +static int security_preserve_bools(struct selinux_policy *oldpolicy, + struct selinux_policy *newpolicy); + +static void selinux_policy_free(struct selinux_policy *policy) +{ + if (!policy) + return; + + sidtab_destroy(policy->sidtab); + kfree(policy->map.mapping); + policydb_destroy(&policy->policydb); + kfree(policy->sidtab); + kfree(policy); +} + +static void selinux_policy_cond_free(struct selinux_policy *policy) +{ + cond_policydb_destroy_dup(&policy->policydb); + kfree(policy); +} + +void selinux_policy_cancel(struct selinux_state *state, + struct selinux_load_state *load_state) +{ + struct selinux_policy *oldpolicy; + + oldpolicy = rcu_dereference_protected(state->policy, + lockdep_is_held(&state->policy_mutex)); + + sidtab_cancel_convert(oldpolicy->sidtab); + selinux_policy_free(load_state->policy); + kfree(load_state->convert_data); +} + +static void selinux_notify_policy_change(struct selinux_state *state, + u32 seqno) +{ + /* Flush external caches and notify userspace of policy load */ + avc_ss_reset(state->avc, seqno); + selnl_notify_policyload(seqno); + selinux_status_update_policyload(state, seqno); + selinux_netlbl_cache_invalidate(); + selinux_xfrm_notify_policyload(); + selinux_ima_measure_state_locked(state); +} + +void selinux_policy_commit(struct selinux_state *state, + struct selinux_load_state *load_state) +{ + struct selinux_policy *oldpolicy, *newpolicy = load_state->policy; + unsigned long flags; + u32 seqno; + + oldpolicy = rcu_dereference_protected(state->policy, + lockdep_is_held(&state->policy_mutex)); + + /* If switching between different policy types, log MLS status */ + if (oldpolicy) { + if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled) + pr_info("SELinux: Disabling MLS support...\n"); + else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled) + pr_info("SELinux: Enabling MLS support...\n"); + } + + /* Set latest granting seqno for new policy. */ + if (oldpolicy) + newpolicy->latest_granting = oldpolicy->latest_granting + 1; + else + newpolicy->latest_granting = 1; + seqno = newpolicy->latest_granting; + + /* Install the new policy. */ + if (oldpolicy) { + sidtab_freeze_begin(oldpolicy->sidtab, &flags); + rcu_assign_pointer(state->policy, newpolicy); + sidtab_freeze_end(oldpolicy->sidtab, &flags); + } else { + rcu_assign_pointer(state->policy, newpolicy); + } + + /* Load the policycaps from the new policy */ + security_load_policycaps(state, newpolicy); + + if (!selinux_initialized(state)) { + /* + * After first policy load, the security server is + * marked as initialized and ready to handle requests and + * any objects created prior to policy load are then labeled. + */ + selinux_mark_initialized(state); + selinux_complete_init(); + } + + /* Free the old policy */ + synchronize_rcu(); + selinux_policy_free(oldpolicy); + kfree(load_state->convert_data); + + /* Notify others of the policy change */ + selinux_notify_policy_change(state, seqno); +} /** * security_load_policy - Load a security policy configuration. + * @state: SELinux state * @data: binary policy data * @len: length of data in bytes + * @load_state: policy load state * * Load a new set of security policy configuration data, * validate it and convert the SID table as necessary. * This function will flush the access vector cache after * loading the new policy. */ -int security_load_policy(struct selinux_state *state, void *data, size_t len) +int security_load_policy(struct selinux_state *state, void *data, size_t len, + struct selinux_load_state *load_state) { - struct policydb *policydb; - struct sidtab *oldsidtab, *newsidtab; - struct policydb *oldpolicydb, *newpolicydb; - struct selinux_mapping *oldmapping; - struct selinux_map newmap; - struct sidtab_convert_params convert_params; - struct convert_context_args args; - u32 seqno; + struct selinux_policy *newpolicy, *oldpolicy; + struct selinux_policy_convert_data *convert_data; int rc = 0; struct policy_file file = { data, len }, *fp = &file; - policydb = &state->ss->policydb; - - newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL); - if (!newsidtab) + newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL); + if (!newpolicy) return -ENOMEM; - if (!selinux_initialized(state)) { - rc = policydb_read(policydb, fp); - if (rc) { - kfree(newsidtab); - return rc; - } - - policydb->len = len; - rc = selinux_set_mapping(policydb, secclass_map, - &state->ss->map); - if (rc) { - kfree(newsidtab); - policydb_destroy(policydb); - return rc; - } - - rc = policydb_load_isids(policydb, newsidtab); - if (rc) { - kfree(newsidtab); - policydb_destroy(policydb); - return rc; - } - - state->ss->sidtab = newsidtab; - security_load_policycaps(state); - selinux_mark_initialized(state); - seqno = ++state->ss->latest_granting; - selinux_complete_init(); - avc_ss_reset(state->avc, seqno); - selnl_notify_policyload(seqno); - selinux_status_update_policyload(state, seqno); - selinux_netlbl_cache_invalidate(); - selinux_xfrm_notify_policyload(); - return 0; - } - - oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL); - if (!oldpolicydb) { - kfree(newsidtab); - return -ENOMEM; + newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL); + if (!newpolicy->sidtab) { + rc = -ENOMEM; + goto err_policy; } - newpolicydb = oldpolicydb + 1; - rc = policydb_read(newpolicydb, fp); - if (rc) { - kfree(newsidtab); - goto out; - } + rc = policydb_read(&newpolicy->policydb, fp); + if (rc) + goto err_sidtab; - newpolicydb->len = len; - /* If switching between different policy types, log MLS status */ - if (policydb->mls_enabled && !newpolicydb->mls_enabled) - pr_info("SELinux: Disabling MLS support...\n"); - else if (!policydb->mls_enabled && newpolicydb->mls_enabled) - pr_info("SELinux: Enabling MLS support...\n"); + newpolicy->policydb.len = len; + rc = selinux_set_mapping(&newpolicy->policydb, secclass_map, + &newpolicy->map); + if (rc) + goto err_policydb; - rc = policydb_load_isids(newpolicydb, newsidtab); + rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab); if (rc) { pr_err("SELinux: unable to load the initial SIDs\n"); - policydb_destroy(newpolicydb); - kfree(newsidtab); - goto out; + goto err_mapping; } - rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap); - if (rc) - goto err; + if (!selinux_initialized(state)) { + /* First policy load, so no need to preserve state from old policy */ + load_state->policy = newpolicy; + load_state->convert_data = NULL; + return 0; + } + + oldpolicy = rcu_dereference_protected(state->policy, + lockdep_is_held(&state->policy_mutex)); - rc = security_preserve_bools(state, newpolicydb); + /* Preserve active boolean values from the old policy */ + rc = security_preserve_bools(oldpolicy, newpolicy); if (rc) { pr_err("SELinux: unable to preserve booleans\n"); - goto err; + goto err_free_isids; } - oldsidtab = state->ss->sidtab; + convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL); + if (!convert_data) { + rc = -ENOMEM; + goto err_free_isids; + } /* * Convert the internal representations of contexts * in the new SID table. */ - args.state = state; - args.oldp = policydb; - args.newp = newpolicydb; + convert_data->args.state = state; + convert_data->args.oldp = &oldpolicy->policydb; + convert_data->args.newp = &newpolicy->policydb; - convert_params.func = convert_context; - convert_params.args = &args; - convert_params.target = newsidtab; + convert_data->sidtab_params.func = convert_context; + convert_data->sidtab_params.args = &convert_data->args; + convert_data->sidtab_params.target = newpolicy->sidtab; - rc = sidtab_convert(oldsidtab, &convert_params); + rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params); if (rc) { pr_err("SELinux: unable to convert the internal" " representation of contexts in the new SID" " table\n"); - goto err; + goto err_free_convert_data; } - /* Save the old policydb and SID table to free later. */ - memcpy(oldpolicydb, policydb, sizeof(*policydb)); - - /* Install the new policydb and SID table. */ - write_lock_irq(&state->ss->policy_rwlock); - memcpy(policydb, newpolicydb, sizeof(*policydb)); - state->ss->sidtab = newsidtab; - security_load_policycaps(state); - oldmapping = state->ss->map.mapping; - state->ss->map.mapping = newmap.mapping; - state->ss->map.size = newmap.size; - seqno = ++state->ss->latest_granting; - write_unlock_irq(&state->ss->policy_rwlock); - - /* Free the old policydb and SID table. */ - policydb_destroy(oldpolicydb); - sidtab_destroy(oldsidtab); - kfree(oldsidtab); - kfree(oldmapping); - - avc_ss_reset(state->avc, seqno); - selnl_notify_policyload(seqno); - selinux_status_update_policyload(state, seqno); - selinux_netlbl_cache_invalidate(); - selinux_xfrm_notify_policyload(); - - rc = 0; - goto out; + load_state->policy = newpolicy; + load_state->convert_data = convert_data; + return 0; -err: - kfree(newmap.mapping); - sidtab_destroy(newsidtab); - kfree(newsidtab); - policydb_destroy(newpolicydb); +err_free_convert_data: + kfree(convert_data); +err_free_isids: + sidtab_destroy(newpolicy->sidtab); +err_mapping: + kfree(newpolicy->map.mapping); +err_policydb: + policydb_destroy(&newpolicy->policydb); +err_sidtab: + kfree(newpolicy->sidtab); +err_policy: + kfree(newpolicy); -out: - kfree(oldpolicydb); return rc; } -size_t security_policydb_len(struct selinux_state *state) +/** + * ocontext_to_sid - Helper to safely get sid for an ocontext + * @sidtab: SID table + * @c: ocontext structure + * @index: index of the context entry (0 or 1) + * @out_sid: pointer to the resulting SID value + * + * For all ocontexts except OCON_ISID the SID fields are populated + * on-demand when needed. Since updating the SID value is an SMP-sensitive + * operation, this helper must be used to do that safely. + * + * WARNING: This function may return -ESTALE, indicating that the caller + * must retry the operation after re-acquiring the policy pointer! + */ +static int ocontext_to_sid(struct sidtab *sidtab, struct ocontext *c, + size_t index, u32 *out_sid) { - struct policydb *p = &state->ss->policydb; - size_t len; + int rc; + u32 sid; - read_lock(&state->ss->policy_rwlock); - len = p->len; - read_unlock(&state->ss->policy_rwlock); + /* Ensure the associated sidtab entry is visible to this thread. */ + sid = smp_load_acquire(&c->sid[index]); + if (!sid) { + rc = sidtab_context_to_sid(sidtab, &c->context[index], &sid); + if (rc) + return rc; - return len; + /* + * Ensure the new sidtab entry is visible to other threads + * when they see the SID. + */ + smp_store_release(&c->sid[index], sid); + } + *out_sid = sid; + return 0; } /** * security_port_sid - Obtain the SID for a port. + * @state: SELinux state * @protocol: protocol number * @port: port number * @out_sid: security identifier @@ -2346,13 +2426,23 @@ size_t security_policydb_len(struct selinux_state *state) int security_port_sid(struct selinux_state *state, u8 protocol, u16 port, u32 *out_sid) { + struct selinux_policy *policy; struct policydb *policydb; + struct sidtab *sidtab; struct ocontext *c; - int rc = 0; + int rc; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + *out_sid = SECINITSID_PORT; + return 0; + } - policydb = &state->ss->policydb; +retry: + rc = 0; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; c = policydb->ocontexts[OCON_PORT]; while (c) { @@ -2364,24 +2454,25 @@ int security_port_sid(struct selinux_state *state, } if (c) { - if (!c->sid[0]) { - rc = context_struct_to_sid(state, &c->context[0], - &c->sid[0]); - if (rc) - goto out; + rc = ocontext_to_sid(sidtab, c, 0, out_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; } - *out_sid = c->sid[0]; + if (rc) + goto out; } else { *out_sid = SECINITSID_PORT; } out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } /** - * security_pkey_sid - Obtain the SID for a pkey. + * security_ib_pkey_sid - Obtain the SID for a pkey. + * @state: SELinux state * @subnet_prefix: Subnet Prefix * @pkey_num: pkey number * @out_sid: security identifier @@ -2389,13 +2480,23 @@ out: int security_ib_pkey_sid(struct selinux_state *state, u64 subnet_prefix, u16 pkey_num, u32 *out_sid) { + struct selinux_policy *policy; struct policydb *policydb; + struct sidtab *sidtab; struct ocontext *c; - int rc = 0; + int rc; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + *out_sid = SECINITSID_UNLABELED; + return 0; + } - policydb = &state->ss->policydb; +retry: + rc = 0; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; c = policydb->ocontexts[OCON_IBPKEY]; while (c) { @@ -2408,38 +2509,48 @@ int security_ib_pkey_sid(struct selinux_state *state, } if (c) { - if (!c->sid[0]) { - rc = context_struct_to_sid(state, - &c->context[0], - &c->sid[0]); - if (rc) - goto out; + rc = ocontext_to_sid(sidtab, c, 0, out_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; } - *out_sid = c->sid[0]; + if (rc) + goto out; } else *out_sid = SECINITSID_UNLABELED; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } /** * security_ib_endport_sid - Obtain the SID for a subnet management interface. + * @state: SELinux state * @dev_name: device name - * @port: port number + * @port_num: port number * @out_sid: security identifier */ int security_ib_endport_sid(struct selinux_state *state, const char *dev_name, u8 port_num, u32 *out_sid) { + struct selinux_policy *policy; struct policydb *policydb; + struct sidtab *sidtab; struct ocontext *c; - int rc = 0; + int rc; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + *out_sid = SECINITSID_UNLABELED; + return 0; + } - policydb = &state->ss->policydb; +retry: + rc = 0; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; c = policydb->ocontexts[OCON_IBENDPORT]; while (c) { @@ -2453,36 +2564,47 @@ int security_ib_endport_sid(struct selinux_state *state, } if (c) { - if (!c->sid[0]) { - rc = context_struct_to_sid(state, &c->context[0], - &c->sid[0]); - if (rc) - goto out; + rc = ocontext_to_sid(sidtab, c, 0, out_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; } - *out_sid = c->sid[0]; + if (rc) + goto out; } else *out_sid = SECINITSID_UNLABELED; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } /** * security_netif_sid - Obtain the SID for a network interface. + * @state: SELinux state * @name: interface name * @if_sid: interface SID */ int security_netif_sid(struct selinux_state *state, char *name, u32 *if_sid) { + struct selinux_policy *policy; struct policydb *policydb; - int rc = 0; + struct sidtab *sidtab; + int rc; struct ocontext *c; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + *if_sid = SECINITSID_NETIF; + return 0; + } - policydb = &state->ss->policydb; +retry: + rc = 0; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; c = policydb->ocontexts[OCON_NETIF]; while (c) { @@ -2492,22 +2614,18 @@ int security_netif_sid(struct selinux_state *state, } if (c) { - if (!c->sid[0] || !c->sid[1]) { - rc = context_struct_to_sid(state, &c->context[0], - &c->sid[0]); - if (rc) - goto out; - rc = context_struct_to_sid(state, &c->context[1], - &c->sid[1]); - if (rc) - goto out; + rc = ocontext_to_sid(sidtab, c, 0, if_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; } - *if_sid = c->sid[0]; + if (rc) + goto out; } else *if_sid = SECINITSID_NETIF; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } @@ -2526,6 +2644,7 @@ static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) /** * security_node_sid - Obtain the SID for a node (host). + * @state: SELinux state * @domain: communication domain aka address family * @addrp: address * @addrlen: address length in bytes @@ -2537,13 +2656,22 @@ int security_node_sid(struct selinux_state *state, u32 addrlen, u32 *out_sid) { + struct selinux_policy *policy; struct policydb *policydb; + struct sidtab *sidtab; int rc; struct ocontext *c; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + *out_sid = SECINITSID_NODE; + return 0; + } - policydb = &state->ss->policydb; +retry: + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; switch (domain) { case AF_INET: { @@ -2584,21 +2712,20 @@ int security_node_sid(struct selinux_state *state, } if (c) { - if (!c->sid[0]) { - rc = context_struct_to_sid(state, - &c->context[0], - &c->sid[0]); - if (rc) - goto out; + rc = ocontext_to_sid(sidtab, c, 0, out_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; } - *out_sid = c->sid[0]; + if (rc) + goto out; } else { *out_sid = SECINITSID_NODE; } rc = 0; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } @@ -2606,6 +2733,7 @@ out: /** * security_get_user_sids - Obtain reachable SIDs for a user. + * @state: SELinux state * @fromsid: starting SID * @username: username * @sids: array of reachable SIDs for user @@ -2624,26 +2752,33 @@ int security_get_user_sids(struct selinux_state *state, u32 **sids, u32 *nel) { + struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct context *fromcon, usercon; u32 *mysids = NULL, *mysids2, sid; - u32 mynel = 0, maxnel = SIDS_NEL; + u32 i, j, mynel, maxnel = SIDS_NEL; struct user_datum *user; struct role_datum *role; struct ebitmap_node *rnode, *tnode; - int rc = 0, i, j; + int rc; *sids = NULL; *nel = 0; if (!selinux_initialized(state)) - goto out; + return 0; - read_lock(&state->ss->policy_rwlock); + mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL); + if (!mysids) + return -ENOMEM; - policydb = &state->ss->policydb; - sidtab = state->ss->sidtab; +retry: + mynel = 0; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; context_init(&usercon); @@ -2653,33 +2788,27 @@ int security_get_user_sids(struct selinux_state *state, goto out_unlock; rc = -EINVAL; - user = hashtab_search(policydb->p_users.table, username); + user = symtab_search(&policydb->p_users, username); if (!user) goto out_unlock; usercon.user = user->value; - rc = -ENOMEM; - mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); - if (!mysids) - goto out_unlock; - ebitmap_for_each_positive_bit(&user->roles, rnode, i) { role = policydb->role_val_to_struct[i]; usercon.role = i + 1; ebitmap_for_each_positive_bit(&role->types, tnode, j) { usercon.type = j + 1; - /* - * The same context struct is reused here so the hash - * must be reset. - */ - usercon.hash = 0; if (mls_setup_user_range(policydb, fromcon, user, &usercon)) continue; - rc = context_struct_to_sid(state, &usercon, &sid); + rc = sidtab_context_to_sid(sidtab, &usercon, &sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; + } if (rc) goto out_unlock; if (mynel < maxnel) { @@ -2699,17 +2828,17 @@ int security_get_user_sids(struct selinux_state *state, } rc = 0; out_unlock: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); if (rc || !mynel) { kfree(mysids); - goto out; + return rc; } rc = -ENOMEM; mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); if (!mysids2) { kfree(mysids); - goto out; + return rc; } for (i = 0, j = 0; i < mynel; i++) { struct av_decision dummy_avd; @@ -2722,44 +2851,45 @@ out_unlock: mysids2[j++] = mysids[i]; cond_resched(); } - rc = 0; kfree(mysids); *sids = mysids2; *nel = j; -out: - return rc; + return 0; } /** * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem + * @policy: policy * @fstype: filesystem type * @path: path from root of mount - * @sclass: file security class + * @orig_sclass: file security class * @sid: SID for path * * Obtain a SID to use for a file in a filesystem that * cannot support xattr or use a fixed labeling behavior like * transition SIDs or task SIDs. * - * The caller must acquire the policy_rwlock before calling this function. + * WARNING: This function may return -ESTALE, indicating that the caller + * must retry the operation after re-acquiring the policy pointer! */ -static inline int __security_genfs_sid(struct selinux_state *state, +static inline int __security_genfs_sid(struct selinux_policy *policy, const char *fstype, - char *path, + const char *path, u16 orig_sclass, u32 *sid) { - struct policydb *policydb = &state->ss->policydb; + struct policydb *policydb = &policy->policydb; + struct sidtab *sidtab = policy->sidtab; int len; u16 sclass; struct genfs *genfs; struct ocontext *c; - int rc, cmp = 0; + int cmp = 0; while (path[0] == '/' && path[1] == '/') path++; - sclass = unmap_class(&state->ss->map, orig_sclass); + sclass = unmap_class(&policy->map, orig_sclass); *sid = SECINITSID_UNLABELED; for (genfs = policydb->genfs; genfs; genfs = genfs->next) { @@ -2768,9 +2898,8 @@ static inline int __security_genfs_sid(struct selinux_state *state, break; } - rc = -ENOENT; if (!genfs || cmp) - goto out; + return -ENOENT; for (c = genfs->head; c; c = c->next) { len = strlen(c->u.name); @@ -2779,27 +2908,18 @@ static inline int __security_genfs_sid(struct selinux_state *state, break; } - rc = -ENOENT; if (!c) - goto out; - - if (!c->sid[0]) { - rc = context_struct_to_sid(state, &c->context[0], &c->sid[0]); - if (rc) - goto out; - } + return -ENOENT; - *sid = c->sid[0]; - rc = 0; -out: - return rc; + return ocontext_to_sid(sidtab, c, 0, sid); } /** * security_genfs_sid - Obtain a SID for a file in a filesystem + * @state: SELinux state * @fstype: filesystem type * @path: path from root of mount - * @sclass: file security class + * @orig_sclass: file security class * @sid: SID for path * * Acquire policy_rwlock before calling __security_genfs_sid() and release @@ -2807,33 +2927,64 @@ out: */ int security_genfs_sid(struct selinux_state *state, const char *fstype, - char *path, + const char *path, u16 orig_sclass, u32 *sid) { + struct selinux_policy *policy; int retval; - read_lock(&state->ss->policy_rwlock); - retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid); - read_unlock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + *sid = SECINITSID_UNLABELED; + return 0; + } + + do { + rcu_read_lock(); + policy = rcu_dereference(state->policy); + retval = __security_genfs_sid(policy, fstype, path, + orig_sclass, sid); + rcu_read_unlock(); + } while (retval == -ESTALE); return retval; } +int selinux_policy_genfs_sid(struct selinux_policy *policy, + const char *fstype, + const char *path, + u16 orig_sclass, + u32 *sid) +{ + /* no lock required, policy is not yet accessible by other threads */ + return __security_genfs_sid(policy, fstype, path, orig_sclass, sid); +} + /** * security_fs_use - Determine how to handle labeling for a filesystem. + * @state: SELinux state * @sb: superblock in question */ int security_fs_use(struct selinux_state *state, struct super_block *sb) { + struct selinux_policy *policy; struct policydb *policydb; - int rc = 0; + struct sidtab *sidtab; + int rc; struct ocontext *c; - struct superblock_security_struct *sbsec = sb->s_security; + struct superblock_security_struct *sbsec = selinux_superblock(sb); const char *fstype = sb->s_type->name; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) { + sbsec->behavior = SECURITY_FS_USE_NONE; + sbsec->sid = SECINITSID_UNLABELED; + return 0; + } - policydb = &state->ss->policydb; +retry: + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; c = policydb->ocontexts[OCON_FSUSE]; while (c) { @@ -2844,16 +2995,20 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb) if (c) { sbsec->behavior = c->v.behavior; - if (!c->sid[0]) { - rc = context_struct_to_sid(state, &c->context[0], - &c->sid[0]); - if (rc) - goto out; + rc = ocontext_to_sid(sidtab, c, 0, &sbsec->sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; } - sbsec->sid = c->sid[0]; + if (rc) + goto out; } else { - rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR, - &sbsec->sid); + rc = __security_genfs_sid(policy, fstype, "/", + SECCLASS_DIR, &sbsec->sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; + } if (rc) { sbsec->behavior = SECURITY_FS_USE_NONE; rc = 0; @@ -2863,26 +3018,18 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb) } out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } -int security_get_bools(struct selinux_state *state, - int *len, char ***names, int **values) +int security_get_bools(struct selinux_policy *policy, + u32 *len, char ***names, int **values) { struct policydb *policydb; - int i, rc; - - if (!selinux_initialized(state)) { - *len = 0; - *names = NULL; - *values = NULL; - return 0; - } - - read_lock(&state->ss->policy_rwlock); + u32 i; + int rc; - policydb = &state->ss->policydb; + policydb = &policy->policydb; *names = NULL; *values = NULL; @@ -2913,80 +3060,106 @@ int security_get_bools(struct selinux_state *state, } rc = 0; out: - read_unlock(&state->ss->policy_rwlock); return rc; err: if (*names) { for (i = 0; i < *len; i++) kfree((*names)[i]); + kfree(*names); } kfree(*values); + *len = 0; + *names = NULL; + *values = NULL; goto out; } -int security_set_bools(struct selinux_state *state, int len, int *values) +int security_set_bools(struct selinux_state *state, u32 len, int *values) { - struct policydb *policydb; - int i, rc; - int lenp, seqno = 0; - struct cond_node *cur; + struct selinux_policy *newpolicy, *oldpolicy; + int rc; + u32 i, seqno = 0; - write_lock_irq(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) + return -EINVAL; - policydb = &state->ss->policydb; + oldpolicy = rcu_dereference_protected(state->policy, + lockdep_is_held(&state->policy_mutex)); - rc = -EFAULT; - lenp = policydb->p_bools.nprim; - if (len != lenp) - goto out; + /* Consistency check on number of booleans, should never fail */ + if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim)) + return -EINVAL; + newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL); + if (!newpolicy) + return -ENOMEM; + + /* + * Deep copy only the parts of the policydb that might be + * modified as a result of changing booleans. + */ + rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb); + if (rc) { + kfree(newpolicy); + return -ENOMEM; + } + + /* Update the boolean states in the copy */ for (i = 0; i < len; i++) { - if (!!values[i] != policydb->bool_val_to_struct[i]->state) { + int new_state = !!values[i]; + int old_state = newpolicy->policydb.bool_val_to_struct[i]->state; + + if (new_state != old_state) { audit_log(audit_context(), GFP_ATOMIC, AUDIT_MAC_CONFIG_CHANGE, "bool=%s val=%d old_val=%d auid=%u ses=%u", - sym_name(policydb, SYM_BOOLS, i), - !!values[i], - policydb->bool_val_to_struct[i]->state, + sym_name(&newpolicy->policydb, SYM_BOOLS, i), + new_state, + old_state, from_kuid(&init_user_ns, audit_get_loginuid(current)), audit_get_sessionid(current)); + newpolicy->policydb.bool_val_to_struct[i]->state = new_state; } - if (values[i]) - policydb->bool_val_to_struct[i]->state = 1; - else - policydb->bool_val_to_struct[i]->state = 0; } - for (cur = policydb->cond_list; cur; cur = cur->next) { - rc = evaluate_cond_node(policydb, cur); - if (rc) - goto out; - } + /* Re-evaluate the conditional rules in the copy */ + evaluate_cond_nodes(&newpolicy->policydb); - seqno = ++state->ss->latest_granting; - rc = 0; -out: - write_unlock_irq(&state->ss->policy_rwlock); - if (!rc) { - avc_ss_reset(state->avc, seqno); - selnl_notify_policyload(seqno); - selinux_status_update_policyload(state, seqno); - selinux_xfrm_notify_policyload(); - } - return rc; + /* Set latest granting seqno for new policy */ + newpolicy->latest_granting = oldpolicy->latest_granting + 1; + seqno = newpolicy->latest_granting; + + /* Install the new policy */ + rcu_assign_pointer(state->policy, newpolicy); + + /* + * Free the conditional portions of the old policydb + * that were copied for the new policy, and the oldpolicy + * structure itself but not what it references. + */ + synchronize_rcu(); + selinux_policy_cond_free(oldpolicy); + + /* Notify others of the policy change */ + selinux_notify_policy_change(state, seqno); + return 0; } int security_get_bool_value(struct selinux_state *state, - int index) + u32 index) { + struct selinux_policy *policy; struct policydb *policydb; int rc; - int len; + u32 len; - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) + return 0; - policydb = &state->ss->policydb; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; rc = -EFAULT; len = policydb->p_bools.nprim; @@ -2995,31 +3168,28 @@ int security_get_bool_value(struct selinux_state *state, rc = policydb->bool_val_to_struct[index]->state; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } -static int security_preserve_bools(struct selinux_state *state, - struct policydb *policydb) +static int security_preserve_bools(struct selinux_policy *oldpolicy, + struct selinux_policy *newpolicy) { - int rc, nbools = 0, *bvalues = NULL, i; + int rc, *bvalues = NULL; char **bnames = NULL; struct cond_bool_datum *booldatum; - struct cond_node *cur; + u32 i, nbools = 0; - rc = security_get_bools(state, &nbools, &bnames, &bvalues); + rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues); if (rc) goto out; for (i = 0; i < nbools; i++) { - booldatum = hashtab_search(policydb->p_bools.table, bnames[i]); + booldatum = symtab_search(&newpolicy->policydb.p_bools, + bnames[i]); if (booldatum) booldatum->state = bvalues[i]; } - for (cur = policydb->cond_list; cur; cur = cur->next) { - rc = evaluate_cond_node(policydb, cur); - if (rc) - goto out; - } + evaluate_cond_nodes(&newpolicy->policydb); out: if (bnames) { @@ -3038,8 +3208,9 @@ out: int security_sid_mls_copy(struct selinux_state *state, u32 sid, u32 mls_sid, u32 *new_sid) { - struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = state->ss->sidtab; + struct selinux_policy *policy; + struct policydb *policydb; + struct sidtab *sidtab; struct context *context1; struct context *context2; struct context newcon; @@ -3047,15 +3218,24 @@ int security_sid_mls_copy(struct selinux_state *state, u32 len; int rc; - rc = 0; - if (!selinux_initialized(state) || !policydb->mls_enabled) { + if (!selinux_initialized(state)) { *new_sid = sid; - goto out; + return 0; } +retry: + rc = 0; context_init(&newcon); - read_lock(&state->ss->policy_rwlock); + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; + + if (!policydb->mls_enabled) { + *new_sid = sid; + goto out_unlock; + } rc = -EINVAL; context1 = sidtab_search(sidtab, sid); @@ -3082,7 +3262,8 @@ int security_sid_mls_copy(struct selinux_state *state, /* Check the validity of the new context. */ if (!policydb_context_isvalid(policydb, &newcon)) { - rc = convert_context_handle_invalid_context(state, &newcon); + rc = convert_context_handle_invalid_context(state, policydb, + &newcon); if (rc) { if (!context_struct_to_string(policydb, &newcon, &s, &len)) { @@ -3101,19 +3282,25 @@ int security_sid_mls_copy(struct selinux_state *state, goto out_unlock; } } - rc = context_struct_to_sid(state, &newcon, new_sid); + rc = sidtab_context_to_sid(sidtab, &newcon, new_sid); + if (rc == -ESTALE) { + rcu_read_unlock(); + context_destroy(&newcon); + goto retry; + } out_unlock: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); context_destroy(&newcon); -out: return rc; } /** * security_net_peersid_resolve - Compare and resolve two network peer SIDs + * @state: SELinux state * @nlbl_sid: NetLabel SID * @nlbl_type: NetLabel labeling protocol type * @xfrm_sid: XFRM SID + * @peer_sid: network peer sid * * Description: * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be @@ -3134,8 +3321,9 @@ int security_net_peersid_resolve(struct selinux_state *state, u32 xfrm_sid, u32 *peer_sid) { - struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = state->ss->sidtab; + struct selinux_policy *policy; + struct policydb *policydb; + struct sidtab *sidtab; int rc; struct context *nlbl_ctx; struct context *xfrm_ctx; @@ -3157,15 +3345,23 @@ int security_net_peersid_resolve(struct selinux_state *state, return 0; } + if (!selinux_initialized(state)) + return 0; + + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; + /* * We don't need to check initialized here since the only way both * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the * security server was initialized and state->initialized was true. */ - if (!policydb->mls_enabled) - return 0; - - read_lock(&state->ss->policy_rwlock); + if (!policydb->mls_enabled) { + rc = 0; + goto out; + } rc = -EINVAL; nlbl_ctx = sidtab_search(sidtab, nlbl_sid); @@ -3192,7 +3388,7 @@ int security_net_peersid_resolve(struct selinux_state *state, * expressive */ *peer_sid = xfrm_sid; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } @@ -3209,19 +3405,13 @@ static int get_classes_callback(void *k, void *d, void *args) return 0; } -int security_get_classes(struct selinux_state *state, +int security_get_classes(struct selinux_policy *policy, char ***classes, int *nclasses) { - struct policydb *policydb = &state->ss->policydb; + struct policydb *policydb; int rc; - if (!selinux_initialized(state)) { - *nclasses = 0; - *classes = NULL; - return 0; - } - - read_lock(&state->ss->policy_rwlock); + policydb = &policy->policydb; rc = -ENOMEM; *nclasses = policydb->p_classes.nprim; @@ -3229,8 +3419,8 @@ int security_get_classes(struct selinux_state *state, if (!*classes) goto out; - rc = hashtab_map(policydb->p_classes.table, get_classes_callback, - *classes); + rc = hashtab_map(&policydb->p_classes.table, get_classes_callback, + *classes); if (rc) { int i; for (i = 0; i < *nclasses; i++) @@ -3239,7 +3429,6 @@ int security_get_classes(struct selinux_state *state, } out: - read_unlock(&state->ss->policy_rwlock); return rc; } @@ -3256,17 +3445,17 @@ static int get_permissions_callback(void *k, void *d, void *args) return 0; } -int security_get_permissions(struct selinux_state *state, +int security_get_permissions(struct selinux_policy *policy, char *class, char ***perms, int *nperms) { - struct policydb *policydb = &state->ss->policydb; + struct policydb *policydb; int rc, i; struct class_datum *match; - read_lock(&state->ss->policy_rwlock); + policydb = &policy->policydb; rc = -EINVAL; - match = hashtab_search(policydb->p_classes.table, class); + match = symtab_search(&policydb->p_classes, class); if (!match) { pr_err("SELinux: %s: unrecognized class %s\n", __func__, class); @@ -3280,23 +3469,21 @@ int security_get_permissions(struct selinux_state *state, goto out; if (match->comdatum) { - rc = hashtab_map(match->comdatum->permissions.table, - get_permissions_callback, *perms); + rc = hashtab_map(&match->comdatum->permissions.table, + get_permissions_callback, *perms); if (rc) goto err; } - rc = hashtab_map(match->permissions.table, get_permissions_callback, - *perms); + rc = hashtab_map(&match->permissions.table, get_permissions_callback, + *perms); if (rc) goto err; out: - read_unlock(&state->ss->policy_rwlock); return rc; err: - read_unlock(&state->ss->policy_rwlock); for (i = 0; i < *nperms; i++) kfree((*perms)[i]); kfree(*perms); @@ -3305,16 +3492,37 @@ err: int security_get_reject_unknown(struct selinux_state *state) { - return state->ss->policydb.reject_unknown; + struct selinux_policy *policy; + int value; + + if (!selinux_initialized(state)) + return 0; + + rcu_read_lock(); + policy = rcu_dereference(state->policy); + value = policy->policydb.reject_unknown; + rcu_read_unlock(); + return value; } int security_get_allow_unknown(struct selinux_state *state) { - return state->ss->policydb.allow_unknown; + struct selinux_policy *policy; + int value; + + if (!selinux_initialized(state)) + return 0; + + rcu_read_lock(); + policy = rcu_dereference(state->policy); + value = policy->policydb.allow_unknown; + rcu_read_unlock(); + return value; } /** * security_policycap_supported - Check for a specific policy capability + * @state: SELinux state * @req_cap: capability * * Description: @@ -3326,12 +3534,16 @@ int security_get_allow_unknown(struct selinux_state *state) int security_policycap_supported(struct selinux_state *state, unsigned int req_cap) { - struct policydb *policydb = &state->ss->policydb; + struct selinux_policy *policy; int rc; - read_lock(&state->ss->policy_rwlock); - rc = ebitmap_get_bit(&policydb->policycaps, req_cap); - read_unlock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) + return 0; + + rcu_read_lock(); + policy = rcu_dereference(state->policy); + rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap); + rcu_read_unlock(); return rc; } @@ -3354,7 +3566,8 @@ void selinux_audit_rule_free(void *vrule) int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) { struct selinux_state *state = &selinux_state; - struct policydb *policydb = &state->ss->policydb; + struct selinux_policy *policy; + struct policydb *policydb; struct selinux_audit_rule *tmprule; struct role_datum *roledatum; struct type_datum *typedatum; @@ -3397,15 +3610,17 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) context_init(&tmprule->au_ctxt); - read_lock(&state->ss->policy_rwlock); + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; - tmprule->au_seqno = state->ss->latest_granting; + tmprule->au_seqno = policy->latest_granting; switch (field) { case AUDIT_SUBJ_USER: case AUDIT_OBJ_USER: rc = -EINVAL; - userdatum = hashtab_search(policydb->p_users.table, rulestr); + userdatum = symtab_search(&policydb->p_users, rulestr); if (!userdatum) goto out; tmprule->au_ctxt.user = userdatum->value; @@ -3413,7 +3628,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) case AUDIT_SUBJ_ROLE: case AUDIT_OBJ_ROLE: rc = -EINVAL; - roledatum = hashtab_search(policydb->p_roles.table, rulestr); + roledatum = symtab_search(&policydb->p_roles, rulestr); if (!roledatum) goto out; tmprule->au_ctxt.role = roledatum->value; @@ -3421,7 +3636,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) case AUDIT_SUBJ_TYPE: case AUDIT_OBJ_TYPE: rc = -EINVAL; - typedatum = hashtab_search(policydb->p_types.table, rulestr); + typedatum = symtab_search(&policydb->p_types, rulestr); if (!typedatum) goto out; tmprule->au_ctxt.type = typedatum->value; @@ -3438,7 +3653,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) } rc = 0; out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); if (rc) { selinux_audit_rule_free(tmprule); @@ -3478,6 +3693,7 @@ int selinux_audit_rule_known(struct audit_krule *rule) int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule) { struct selinux_state *state = &selinux_state; + struct selinux_policy *policy; struct context *ctxt; struct mls_level *level; struct selinux_audit_rule *rule = vrule; @@ -3488,14 +3704,19 @@ int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule) return -ENOENT; } - read_lock(&state->ss->policy_rwlock); + if (!selinux_initialized(state)) + return 0; + + rcu_read_lock(); - if (rule->au_seqno < state->ss->latest_granting) { + policy = rcu_dereference(state->policy); + + if (rule->au_seqno < policy->latest_granting) { match = -ESTALE; goto out; } - ctxt = sidtab_search(state->ss->sidtab, sid); + ctxt = sidtab_search(policy->sidtab, sid); if (unlikely(!ctxt)) { WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", sid); @@ -3579,19 +3800,15 @@ int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule) } out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return match; } -static int (*aurule_callback)(void) = audit_update_lsm_rules; - static int aurule_avc_callback(u32 event) { - int err = 0; - - if (event == AVC_CALLBACK_RESET && aurule_callback) - err = aurule_callback(); - return err; + if (event == AVC_CALLBACK_RESET) + return audit_update_lsm_rules(); + return 0; } static int __init aurule_init(void) @@ -3640,6 +3857,7 @@ static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, /** * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID + * @state: SELinux state * @secattr: the NetLabel packet security attributes * @sid: the SELinux SID * @@ -3657,8 +3875,9 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state, struct netlbl_lsm_secattr *secattr, u32 *sid) { - struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = state->ss->sidtab; + struct selinux_policy *policy; + struct policydb *policydb; + struct sidtab *sidtab; int rc; struct context *ctx; struct context ctx_new; @@ -3668,7 +3887,12 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state, return 0; } - read_lock(&state->ss->policy_rwlock); +retry: + rc = 0; + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; + sidtab = policy->sidtab; if (secattr->flags & NETLBL_SECATTR_CACHE) *sid = *(u32 *)secattr->cache->data; @@ -3691,30 +3915,32 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state, goto out; } rc = -EIDRM; - if (!mls_context_isvalid(policydb, &ctx_new)) - goto out_free; + if (!mls_context_isvalid(policydb, &ctx_new)) { + ebitmap_destroy(&ctx_new.range.level[0].cat); + goto out; + } - rc = context_struct_to_sid(state, &ctx_new, sid); + rc = sidtab_context_to_sid(sidtab, &ctx_new, sid); + ebitmap_destroy(&ctx_new.range.level[0].cat); + if (rc == -ESTALE) { + rcu_read_unlock(); + goto retry; + } if (rc) - goto out_free; + goto out; security_netlbl_cache_add(secattr, *sid); - - ebitmap_destroy(&ctx_new.range.level[0].cat); } else *sid = SECSID_NULL; - read_unlock(&state->ss->policy_rwlock); - return 0; -out_free: - ebitmap_destroy(&ctx_new.range.level[0].cat); out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } /** * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr + * @state: SELinux state * @sid: the SELinux SID * @secattr: the NetLabel packet security attributes * @@ -3726,17 +3952,20 @@ out: int security_netlbl_sid_to_secattr(struct selinux_state *state, u32 sid, struct netlbl_lsm_secattr *secattr) { - struct policydb *policydb = &state->ss->policydb; + struct selinux_policy *policy; + struct policydb *policydb; int rc; struct context *ctx; if (!selinux_initialized(state)) return 0; - read_lock(&state->ss->policy_rwlock); + rcu_read_lock(); + policy = rcu_dereference(state->policy); + policydb = &policy->policydb; rc = -ENOENT; - ctx = sidtab_search(state->ss->sidtab, sid); + ctx = sidtab_search(policy->sidtab, sid); if (ctx == NULL) goto out; @@ -3751,13 +3980,38 @@ int security_netlbl_sid_to_secattr(struct selinux_state *state, mls_export_netlbl_lvl(policydb, ctx, secattr); rc = mls_export_netlbl_cat(policydb, ctx, secattr); out: - read_unlock(&state->ss->policy_rwlock); + rcu_read_unlock(); return rc; } #endif /* CONFIG_NETLABEL */ /** + * __security_read_policy - read the policy. + * @policy: SELinux policy + * @data: binary policy data + * @len: length of data in bytes + * + */ +static int __security_read_policy(struct selinux_policy *policy, + void *data, size_t *len) +{ + int rc; + struct policy_file fp; + + fp.data = data; + fp.len = *len; + + rc = policydb_write(&policy->policydb, &fp); + if (rc) + return rc; + + *len = (unsigned long)fp.data - (unsigned long)data; + return 0; +} + +/** * security_read_policy - read the policy. + * @state: selinux_state * @data: binary policy data * @len: length of data in bytes * @@ -3765,30 +4019,54 @@ out: int security_read_policy(struct selinux_state *state, void **data, size_t *len) { - struct policydb *policydb = &state->ss->policydb; - int rc; - struct policy_file fp; + struct selinux_policy *policy; - if (!selinux_initialized(state)) + policy = rcu_dereference_protected( + state->policy, lockdep_is_held(&state->policy_mutex)); + if (!policy) return -EINVAL; - *len = security_policydb_len(state); - + *len = policy->policydb.len; *data = vmalloc_user(*len); if (!*data) return -ENOMEM; - fp.data = *data; - fp.len = *len; + return __security_read_policy(policy, *data, len); +} - read_lock(&state->ss->policy_rwlock); - rc = policydb_write(policydb, &fp); - read_unlock(&state->ss->policy_rwlock); +/** + * security_read_state_kernel - read the policy. + * @state: selinux_state + * @data: binary policy data + * @len: length of data in bytes + * + * Allocates kernel memory for reading SELinux policy. + * This function is for internal use only and should not + * be used for returning data to user space. + * + * This function must be called with policy_mutex held. + */ +int security_read_state_kernel(struct selinux_state *state, + void **data, size_t *len) +{ + int err; + struct selinux_policy *policy; - if (rc) - return rc; + policy = rcu_dereference_protected( + state->policy, lockdep_is_held(&state->policy_mutex)); + if (!policy) + return -EINVAL; - *len = (unsigned long)fp.data - (unsigned long)*data; - return 0; + *len = policy->policydb.len; + *data = vmalloc(*len); + if (!*data) + return -ENOMEM; + err = __security_read_policy(policy, *data, len); + if (err) { + vfree(*data); + *data = NULL; + *len = 0; + } + return err; } |