^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Implementation of the kernel access vector cache (AVC).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Authors: Stephen Smalley, <sds@tycho.nsa.gov>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * James Morris <jmorris@redhat.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * Update: KaiGai, Kohei <kaigai@ak.jp.nec.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * Replaced the avc_lock spinlock by RCU.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/stddef.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/dcache.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/skbuff.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/percpu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/list.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <net/sock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/un.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <net/af_unix.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <linux/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <linux/audit.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) #include <linux/ipv6.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) #include <net/ipv6.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) #include "avc.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include "avc_ss.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include "classmap.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #define CREATE_TRACE_POINTS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) #include <trace/events/avc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #define AVC_CACHE_SLOTS 512
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) #define AVC_DEF_CACHE_THRESHOLD 512
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) #define AVC_CACHE_RECLAIM 16
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) #define avc_cache_stats_incr(field) this_cpu_inc(avc_cache_stats.field)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) #define avc_cache_stats_incr(field) do {} while (0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) #undef CREATE_TRACE_POINTS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) #include <trace/hooks/avc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) struct avc_entry {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) u32 ssid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) u32 tsid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) u16 tclass;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) struct av_decision avd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct avc_xperms_node *xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) struct avc_node {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) struct avc_entry ae;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) struct hlist_node list; /* anchored in avc_cache->slots[i] */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) struct rcu_head rhead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) struct avc_xperms_decision_node {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) struct extended_perms_decision xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) struct list_head xpd_list; /* list of extended_perms_decision */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) struct avc_xperms_node {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) struct extended_perms xp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) struct list_head xpd_head; /* list head of extended_perms_decision */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) struct avc_cache {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) struct hlist_head slots[AVC_CACHE_SLOTS]; /* head for avc_node->list */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) spinlock_t slots_lock[AVC_CACHE_SLOTS]; /* lock for writes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) atomic_t lru_hint; /* LRU hint for reclaim scan */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) atomic_t active_nodes;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) u32 latest_notif; /* latest revocation notification */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) struct avc_callback_node {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) int (*callback) (u32 event);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) u32 events;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) struct avc_callback_node *next;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) DEFINE_PER_CPU(struct avc_cache_stats, avc_cache_stats) = { 0 };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) struct selinux_avc {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) unsigned int avc_cache_threshold;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) struct avc_cache avc_cache;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) static struct selinux_avc selinux_avc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) void selinux_avc_init(struct selinux_avc **avc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) selinux_avc.avc_cache_threshold = AVC_DEF_CACHE_THRESHOLD;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) for (i = 0; i < AVC_CACHE_SLOTS; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) INIT_HLIST_HEAD(&selinux_avc.avc_cache.slots[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) spin_lock_init(&selinux_avc.avc_cache.slots_lock[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) atomic_set(&selinux_avc.avc_cache.active_nodes, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) atomic_set(&selinux_avc.avc_cache.lru_hint, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) *avc = &selinux_avc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) unsigned int avc_get_cache_threshold(struct selinux_avc *avc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) return avc->avc_cache_threshold;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) void avc_set_cache_threshold(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) unsigned int cache_threshold)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) avc->avc_cache_threshold = cache_threshold;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) static struct avc_callback_node *avc_callbacks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) static struct kmem_cache *avc_node_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) static struct kmem_cache *avc_xperms_data_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) static struct kmem_cache *avc_xperms_decision_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) static struct kmem_cache *avc_xperms_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) return (ssid ^ (tsid<<2) ^ (tclass<<4)) & (AVC_CACHE_SLOTS - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) * avc_init - Initialize the AVC.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) * Initialize the access vector cache.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) void __init avc_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) avc_node_cachep = kmem_cache_create("avc_node", sizeof(struct avc_node),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 0, SLAB_PANIC, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) avc_xperms_cachep = kmem_cache_create("avc_xperms_node",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) sizeof(struct avc_xperms_node),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 0, SLAB_PANIC, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) avc_xperms_decision_cachep = kmem_cache_create(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) "avc_xperms_decision_node",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) sizeof(struct avc_xperms_decision_node),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 0, SLAB_PANIC, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) avc_xperms_data_cachep = kmem_cache_create("avc_xperms_data",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) sizeof(struct extended_perms_data),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 0, SLAB_PANIC, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) int avc_get_hash_stats(struct selinux_avc *avc, char *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) int i, chain_len, max_chain_len, slots_used;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) struct hlist_head *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) slots_used = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) max_chain_len = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) for (i = 0; i < AVC_CACHE_SLOTS; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) head = &avc->avc_cache.slots[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) if (!hlist_empty(head)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) slots_used++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) chain_len = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) hlist_for_each_entry_rcu(node, head, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) chain_len++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) if (chain_len > max_chain_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) max_chain_len = chain_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) return scnprintf(page, PAGE_SIZE, "entries: %d\nbuckets used: %d/%d\n"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) "longest chain: %d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) atomic_read(&avc->avc_cache.active_nodes),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) slots_used, AVC_CACHE_SLOTS, max_chain_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) * using a linked list for extended_perms_decision lookup because the list is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) * always small. i.e. less than 5, typically 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) static struct extended_perms_decision *avc_xperms_decision_lookup(u8 driver,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) struct avc_xperms_node *xp_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) struct avc_xperms_decision_node *xpd_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) list_for_each_entry(xpd_node, &xp_node->xpd_head, xpd_list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) if (xpd_node->xpd.driver == driver)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) return &xpd_node->xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) static inline unsigned int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) avc_xperms_has_perm(struct extended_perms_decision *xpd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) u8 perm, u8 which)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) unsigned int rc = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) if ((which == XPERMS_ALLOWED) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) (xpd->used & XPERMS_ALLOWED))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) rc = security_xperm_test(xpd->allowed->p, perm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) else if ((which == XPERMS_AUDITALLOW) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) (xpd->used & XPERMS_AUDITALLOW))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) rc = security_xperm_test(xpd->auditallow->p, perm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) else if ((which == XPERMS_DONTAUDIT) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) (xpd->used & XPERMS_DONTAUDIT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) rc = security_xperm_test(xpd->dontaudit->p, perm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) static void avc_xperms_allow_perm(struct avc_xperms_node *xp_node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) u8 driver, u8 perm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) struct extended_perms_decision *xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) security_xperm_set(xp_node->xp.drivers.p, driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) xpd = avc_xperms_decision_lookup(driver, xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) if (xpd && xpd->allowed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) security_xperm_set(xpd->allowed->p, perm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) static void avc_xperms_decision_free(struct avc_xperms_decision_node *xpd_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) struct extended_perms_decision *xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) xpd = &xpd_node->xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) if (xpd->allowed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) kmem_cache_free(avc_xperms_data_cachep, xpd->allowed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) if (xpd->auditallow)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) kmem_cache_free(avc_xperms_data_cachep, xpd->auditallow);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (xpd->dontaudit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) kmem_cache_free(avc_xperms_data_cachep, xpd->dontaudit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) kmem_cache_free(avc_xperms_decision_cachep, xpd_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) static void avc_xperms_free(struct avc_xperms_node *xp_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) struct avc_xperms_decision_node *xpd_node, *tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) if (!xp_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) list_for_each_entry_safe(xpd_node, tmp, &xp_node->xpd_head, xpd_list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) list_del(&xpd_node->xpd_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) avc_xperms_decision_free(xpd_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) kmem_cache_free(avc_xperms_cachep, xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) static void avc_copy_xperms_decision(struct extended_perms_decision *dest,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) struct extended_perms_decision *src)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) dest->driver = src->driver;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) dest->used = src->used;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) if (dest->used & XPERMS_ALLOWED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) memcpy(dest->allowed->p, src->allowed->p,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) sizeof(src->allowed->p));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) if (dest->used & XPERMS_AUDITALLOW)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) memcpy(dest->auditallow->p, src->auditallow->p,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) sizeof(src->auditallow->p));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) if (dest->used & XPERMS_DONTAUDIT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) memcpy(dest->dontaudit->p, src->dontaudit->p,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) sizeof(src->dontaudit->p));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) * similar to avc_copy_xperms_decision, but only copy decision
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) * information relevant to this perm
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) static inline void avc_quick_copy_xperms_decision(u8 perm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) struct extended_perms_decision *dest,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) struct extended_perms_decision *src)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) * compute index of the u32 of the 256 bits (8 u32s) that contain this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) * command permission
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) u8 i = perm >> 5;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) dest->used = src->used;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) if (dest->used & XPERMS_ALLOWED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) dest->allowed->p[i] = src->allowed->p[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) if (dest->used & XPERMS_AUDITALLOW)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) dest->auditallow->p[i] = src->auditallow->p[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) if (dest->used & XPERMS_DONTAUDIT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) dest->dontaudit->p[i] = src->dontaudit->p[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) static struct avc_xperms_decision_node
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) *avc_xperms_decision_alloc(u8 which)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) struct avc_xperms_decision_node *xpd_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) struct extended_perms_decision *xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) GFP_NOWAIT | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) if (!xpd_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) xpd = &xpd_node->xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) if (which & XPERMS_ALLOWED) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) xpd->allowed = kmem_cache_zalloc(avc_xperms_data_cachep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) GFP_NOWAIT | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) if (!xpd->allowed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) if (which & XPERMS_AUDITALLOW) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) xpd->auditallow = kmem_cache_zalloc(avc_xperms_data_cachep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) GFP_NOWAIT | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) if (!xpd->auditallow)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) if (which & XPERMS_DONTAUDIT) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) xpd->dontaudit = kmem_cache_zalloc(avc_xperms_data_cachep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) GFP_NOWAIT | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) if (!xpd->dontaudit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) return xpd_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) avc_xperms_decision_free(xpd_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) static int avc_add_xperms_decision(struct avc_node *node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) struct extended_perms_decision *src)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) struct avc_xperms_decision_node *dest_xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) node->ae.xp_node->xp.len++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) dest_xpd = avc_xperms_decision_alloc(src->used);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) if (!dest_xpd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) avc_copy_xperms_decision(&dest_xpd->xpd, src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) list_add(&dest_xpd->xpd_list, &node->ae.xp_node->xpd_head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) static struct avc_xperms_node *avc_xperms_alloc(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) struct avc_xperms_node *xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) xp_node = kmem_cache_zalloc(avc_xperms_cachep, GFP_NOWAIT | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) if (!xp_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) return xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) INIT_LIST_HEAD(&xp_node->xpd_head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) return xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) static int avc_xperms_populate(struct avc_node *node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) struct avc_xperms_node *src)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) struct avc_xperms_node *dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) struct avc_xperms_decision_node *dest_xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) struct avc_xperms_decision_node *src_xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) if (src->xp.len == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) dest = avc_xperms_alloc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) if (!dest)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) memcpy(dest->xp.drivers.p, src->xp.drivers.p, sizeof(dest->xp.drivers.p));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) dest->xp.len = src->xp.len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) /* for each source xpd allocate a destination xpd and copy */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) list_for_each_entry(src_xpd, &src->xpd_head, xpd_list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) dest_xpd = avc_xperms_decision_alloc(src_xpd->xpd.used);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) if (!dest_xpd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) avc_copy_xperms_decision(&dest_xpd->xpd, &src_xpd->xpd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) list_add(&dest_xpd->xpd_list, &dest->xpd_head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) node->ae.xp_node = dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) avc_xperms_free(dest);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) static inline u32 avc_xperms_audit_required(u32 requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) struct av_decision *avd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) struct extended_perms_decision *xpd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) u8 perm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) int result,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) u32 *deniedp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) u32 denied, audited;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) denied = requested & ~avd->allowed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) if (unlikely(denied)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) audited = denied & avd->auditdeny;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) if (audited && xpd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) if (avc_xperms_has_perm(xpd, perm, XPERMS_DONTAUDIT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) audited &= ~requested;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) } else if (result) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) audited = denied = requested;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) audited = requested & avd->auditallow;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) if (audited && xpd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) if (!avc_xperms_has_perm(xpd, perm, XPERMS_AUDITALLOW))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) audited &= ~requested;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) *deniedp = denied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) return audited;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) static inline int avc_xperms_audit(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) u32 ssid, u32 tsid, u16 tclass,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) u32 requested, struct av_decision *avd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) struct extended_perms_decision *xpd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) u8 perm, int result,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) struct common_audit_data *ad)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) u32 audited, denied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) audited = avc_xperms_audit_required(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) requested, avd, xpd, perm, result, &denied);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) if (likely(!audited))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) return slow_avc_audit(state, ssid, tsid, tclass, requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) audited, denied, result, ad);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) static void avc_node_free(struct rcu_head *rhead)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) struct avc_node *node = container_of(rhead, struct avc_node, rhead);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) avc_xperms_free(node->ae.xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) kmem_cache_free(avc_node_cachep, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) avc_cache_stats_incr(frees);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) static void avc_node_delete(struct selinux_avc *avc, struct avc_node *node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) trace_android_vh_selinux_avc_node_delete(node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) hlist_del_rcu(&node->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) call_rcu(&node->rhead, avc_node_free);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) atomic_dec(&avc->avc_cache.active_nodes);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) static void avc_node_kill(struct selinux_avc *avc, struct avc_node *node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) avc_xperms_free(node->ae.xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) kmem_cache_free(avc_node_cachep, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) avc_cache_stats_incr(frees);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) atomic_dec(&avc->avc_cache.active_nodes);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) static void avc_node_replace(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) struct avc_node *new, struct avc_node *old)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) trace_android_vh_selinux_avc_node_replace(old, new);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) hlist_replace_rcu(&old->list, &new->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) call_rcu(&old->rhead, avc_node_free);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) atomic_dec(&avc->avc_cache.active_nodes);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) static inline int avc_reclaim_node(struct selinux_avc *avc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) int hvalue, try, ecx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) struct hlist_head *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) spinlock_t *lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) for (try = 0, ecx = 0; try < AVC_CACHE_SLOTS; try++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) hvalue = atomic_inc_return(&avc->avc_cache.lru_hint) &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) (AVC_CACHE_SLOTS - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) head = &avc->avc_cache.slots[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) lock = &avc->avc_cache.slots_lock[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) if (!spin_trylock_irqsave(lock, flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) hlist_for_each_entry(node, head, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) avc_node_delete(avc, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) avc_cache_stats_incr(reclaims);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) ecx++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) if (ecx >= AVC_CACHE_RECLAIM) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) spin_unlock_irqrestore(lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) spin_unlock_irqrestore(lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) return ecx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) static struct avc_node *avc_alloc_node(struct selinux_avc *avc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) node = kmem_cache_zalloc(avc_node_cachep, GFP_NOWAIT | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) if (!node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) INIT_HLIST_NODE(&node->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) avc_cache_stats_incr(allocations);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) if (atomic_inc_return(&avc->avc_cache.active_nodes) >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) avc->avc_cache_threshold)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) avc_reclaim_node(avc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) return node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) static void avc_node_populate(struct avc_node *node, u32 ssid, u32 tsid, u16 tclass, struct av_decision *avd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) node->ae.ssid = ssid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) node->ae.tsid = tsid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) node->ae.tclass = tclass;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) memcpy(&node->ae.avd, avd, sizeof(node->ae.avd));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) static inline struct avc_node *avc_search_node(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) u32 ssid, u32 tsid, u16 tclass)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) struct avc_node *node, *ret = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) int hvalue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) struct hlist_head *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) hvalue = avc_hash(ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) head = &avc->avc_cache.slots[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) hlist_for_each_entry_rcu(node, head, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) if (ssid == node->ae.ssid &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) tclass == node->ae.tclass &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) tsid == node->ae.tsid) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) ret = node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) * avc_lookup - Look up an AVC entry.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) * @ssid: source security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) * @tsid: target security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) * @tclass: target security class
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) * Look up an AVC entry that is valid for the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) * (@ssid, @tsid), interpreting the permissions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) * based on @tclass. If a valid AVC entry exists,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) * then this function returns the avc_node.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) * Otherwise, this function returns NULL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) static struct avc_node *avc_lookup(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) u32 ssid, u32 tsid, u16 tclass)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) avc_cache_stats_incr(lookups);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) node = avc_search_node(avc, ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) if (node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) trace_android_vh_selinux_avc_lookup(node, ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) return node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) avc_cache_stats_incr(misses);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) static int avc_latest_notif_update(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) int seqno, int is_insert)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) static DEFINE_SPINLOCK(notif_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) unsigned long flag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) spin_lock_irqsave(¬if_lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) if (is_insert) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) if (seqno < avc->avc_cache.latest_notif) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) pr_warn("SELinux: avc: seqno %d < latest_notif %d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) seqno, avc->avc_cache.latest_notif);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) ret = -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) if (seqno > avc->avc_cache.latest_notif)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) avc->avc_cache.latest_notif = seqno;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) spin_unlock_irqrestore(¬if_lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) * avc_insert - Insert an AVC entry.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) * @ssid: source security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) * @tsid: target security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) * @tclass: target security class
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) * @avd: resulting av decision
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) * @xp_node: resulting extended permissions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) * Insert an AVC entry for the SID pair
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) * (@ssid, @tsid) and class @tclass.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) * The access vectors and the sequence number are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) * normally provided by the security server in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) * response to a security_compute_av() call. If the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) * sequence number @avd->seqno is not less than the latest
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) * revocation notification, then the function copies
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) * the access vectors into a cache entry, returns
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) * avc_node inserted. Otherwise, this function returns NULL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) static struct avc_node *avc_insert(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) u32 ssid, u32 tsid, u16 tclass,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) struct av_decision *avd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) struct avc_xperms_node *xp_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) struct avc_node *pos, *node = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) int hvalue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) unsigned long flag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) spinlock_t *lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) struct hlist_head *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) if (avc_latest_notif_update(avc, avd->seqno, 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) node = avc_alloc_node(avc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) if (!node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) avc_node_populate(node, ssid, tsid, tclass, avd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) if (avc_xperms_populate(node, xp_node)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) avc_node_kill(avc, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) hvalue = avc_hash(ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) head = &avc->avc_cache.slots[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) lock = &avc->avc_cache.slots_lock[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) spin_lock_irqsave(lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) hlist_for_each_entry(pos, head, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) if (pos->ae.ssid == ssid &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) pos->ae.tsid == tsid &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) pos->ae.tclass == tclass) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) avc_node_replace(avc, node, pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) goto found;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) hlist_add_head_rcu(&node->list, head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) trace_android_vh_selinux_avc_insert(node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) found:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) spin_unlock_irqrestore(lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) return node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) * avc_audit_pre_callback - SELinux specific information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) * will be called by generic audit code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) * @ab: the audit buffer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) * @a: audit_data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) static void avc_audit_pre_callback(struct audit_buffer *ab, void *a)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) struct common_audit_data *ad = a;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) struct selinux_audit_data *sad = ad->selinux_audit_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) u32 av = sad->audited;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) const char **perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) int i, perm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) audit_log_format(ab, "avc: %s ", sad->denied ? "denied" : "granted");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) if (av == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) audit_log_format(ab, " null");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) perms = secclass_map[sad->tclass-1].perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) audit_log_format(ab, " {");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) i = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) perm = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) while (i < (sizeof(av) * 8)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) if ((perm & av) && perms[i]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) audit_log_format(ab, " %s", perms[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) av &= ~perm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) i++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) perm <<= 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) if (av)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) audit_log_format(ab, " 0x%x", av);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) audit_log_format(ab, " } for ");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) * avc_audit_post_callback - SELinux specific information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) * will be called by generic audit code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) * @ab: the audit buffer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) * @a: audit_data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) static void avc_audit_post_callback(struct audit_buffer *ab, void *a)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) struct common_audit_data *ad = a;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) struct selinux_audit_data *sad = ad->selinux_audit_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) char *scontext = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) char *tcontext = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) const char *tclass = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) u32 scontext_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) u32 tcontext_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) rc = security_sid_to_context(sad->state, sad->ssid, &scontext,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) &scontext_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) audit_log_format(ab, " ssid=%d", sad->ssid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) audit_log_format(ab, " scontext=%s", scontext);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) rc = security_sid_to_context(sad->state, sad->tsid, &tcontext,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) &tcontext_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) audit_log_format(ab, " tsid=%d", sad->tsid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) audit_log_format(ab, " tcontext=%s", tcontext);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) tclass = secclass_map[sad->tclass-1].name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) audit_log_format(ab, " tclass=%s", tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) if (sad->denied)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) audit_log_format(ab, " permissive=%u", sad->result ? 0 : 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) trace_selinux_audited(sad, scontext, tcontext, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) kfree(tcontext);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) kfree(scontext);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) /* in case of invalid context report also the actual context string */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) rc = security_sid_to_context_inval(sad->state, sad->ssid, &scontext,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) &scontext_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) if (!rc && scontext) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) if (scontext_len && scontext[scontext_len - 1] == '\0')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) scontext_len--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) audit_log_format(ab, " srawcon=");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) audit_log_n_untrustedstring(ab, scontext, scontext_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) kfree(scontext);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) rc = security_sid_to_context_inval(sad->state, sad->tsid, &scontext,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) &scontext_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) if (!rc && scontext) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) if (scontext_len && scontext[scontext_len - 1] == '\0')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) scontext_len--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) audit_log_format(ab, " trawcon=");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) audit_log_n_untrustedstring(ab, scontext, scontext_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) kfree(scontext);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) /* This is the slow part of avc audit with big stack footprint */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) noinline int slow_avc_audit(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) u32 ssid, u32 tsid, u16 tclass,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) u32 requested, u32 audited, u32 denied, int result,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) struct common_audit_data *a)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) struct common_audit_data stack_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) struct selinux_audit_data sad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) if (WARN_ON(!tclass || tclass >= ARRAY_SIZE(secclass_map)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) if (!a) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) a = &stack_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) a->type = LSM_AUDIT_DATA_NONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) sad.tclass = tclass;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) sad.requested = requested;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) sad.ssid = ssid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) sad.tsid = tsid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) sad.audited = audited;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) sad.denied = denied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) sad.result = result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) sad.state = state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) a->selinux_audit_data = &sad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) common_lsm_audit(a, avc_audit_pre_callback, avc_audit_post_callback);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) * avc_add_callback - Register a callback for security events.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) * @callback: callback function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) * @events: security events
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) * Register a callback function for events in the set @events.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) * Returns %0 on success or -%ENOMEM if insufficient memory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) * exists to add the callback.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) int __init avc_add_callback(int (*callback)(u32 event), u32 events)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) struct avc_callback_node *c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) int rc = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) c = kmalloc(sizeof(*c), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817) if (!c) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) rc = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822) c->callback = callback;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) c->events = events;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) c->next = avc_callbacks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) avc_callbacks = c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) * avc_update_node Update an AVC entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) * @event : Updating event
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) * @perms : Permission mask bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) * @ssid,@tsid,@tclass : identifier of an AVC entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) * @seqno : sequence number when decision was made
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) * @xpd: extended_perms_decision to be added to the node
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) * @flags: the AVC_* flags, e.g. AVC_NONBLOCKING, AVC_EXTENDED_PERMS, or 0.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839) * if a valid AVC entry doesn't exist,this function returns -ENOENT.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) * if kmalloc() called internal returns NULL, this function returns -ENOMEM.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) * otherwise, this function updates the AVC entry. The original AVC-entry object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) * will release later by RCU.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844) static int avc_update_node(struct selinux_avc *avc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) u32 event, u32 perms, u8 driver, u8 xperm, u32 ssid,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) u32 tsid, u16 tclass, u32 seqno,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) struct extended_perms_decision *xpd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) u32 flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) int hvalue, rc = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851) unsigned long flag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) struct avc_node *pos, *node, *orig = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) struct hlist_head *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854) spinlock_t *lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) * If we are in a non-blocking code path, e.g. VFS RCU walk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) * then we must not add permissions to a cache entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859) * because we will not audit the denial. Otherwise,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) * during the subsequent blocking retry (e.g. VFS ref walk), we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) * will find the permissions already granted in the cache entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862) * and won't audit anything at all, leading to silent denials in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) * permissive mode that only appear when in enforcing mode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) * See the corresponding handling of MAY_NOT_BLOCK in avc_audit()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) * and selinux_inode_permission().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868) if (flags & AVC_NONBLOCKING)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) node = avc_alloc_node(avc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) if (!node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873) rc = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) /* Lock the target slot */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) hvalue = avc_hash(ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880) head = &avc->avc_cache.slots[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) lock = &avc->avc_cache.slots_lock[hvalue];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) spin_lock_irqsave(lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885) hlist_for_each_entry(pos, head, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) if (ssid == pos->ae.ssid &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) tsid == pos->ae.tsid &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) tclass == pos->ae.tclass &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) seqno == pos->ae.avd.seqno){
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) orig = pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) if (!orig) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) rc = -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) avc_node_kill(avc, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) * Copy and replace original node.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905) avc_node_populate(node, ssid, tsid, tclass, &orig->ae.avd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907) if (orig->ae.xp_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) rc = avc_xperms_populate(node, orig->ae.xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) if (rc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910) avc_node_kill(avc, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) switch (event) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) case AVC_CALLBACK_GRANT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917) node->ae.avd.allowed |= perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) if (node->ae.xp_node && (flags & AVC_EXTENDED_PERMS))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) avc_xperms_allow_perm(node->ae.xp_node, driver, xperm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) case AVC_CALLBACK_TRY_REVOKE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) case AVC_CALLBACK_REVOKE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) node->ae.avd.allowed &= ~perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925) case AVC_CALLBACK_AUDITALLOW_ENABLE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) node->ae.avd.auditallow |= perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) case AVC_CALLBACK_AUDITALLOW_DISABLE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) node->ae.avd.auditallow &= ~perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) case AVC_CALLBACK_AUDITDENY_ENABLE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) node->ae.avd.auditdeny |= perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) case AVC_CALLBACK_AUDITDENY_DISABLE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) node->ae.avd.auditdeny &= ~perms;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937) case AVC_CALLBACK_ADD_XPERMS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) avc_add_xperms_decision(node, xpd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) avc_node_replace(avc, node, orig);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) spin_unlock_irqrestore(lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) * avc_flush - Flush the cache
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) static void avc_flush(struct selinux_avc *avc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) struct hlist_head *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) spinlock_t *lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956) unsigned long flag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) for (i = 0; i < AVC_CACHE_SLOTS; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960) head = &avc->avc_cache.slots[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) lock = &avc->avc_cache.slots_lock[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) spin_lock_irqsave(lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965) * With preemptable RCU, the outer spinlock does not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) * prevent RCU grace periods from ending.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) hlist_for_each_entry(node, head, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) avc_node_delete(avc, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972) spin_unlock_irqrestore(lock, flag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) * avc_ss_reset - Flush the cache and revalidate migrated permissions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) * @seqno: policy sequence number
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980) int avc_ss_reset(struct selinux_avc *avc, u32 seqno)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982) struct avc_callback_node *c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983) int rc = 0, tmprc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) avc_flush(avc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987) for (c = avc_callbacks; c; c = c->next) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) if (c->events & AVC_CALLBACK_RESET) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989) tmprc = c->callback(AVC_CALLBACK_RESET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990) /* save the first error encountered for the return
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) value and continue processing the callbacks */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) if (!rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993) rc = tmprc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997) avc_latest_notif_update(avc, seqno, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002) * Slow-path helper function for avc_has_perm_noaudit,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) * when the avc_node lookup fails. We get called with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) * the RCU read lock held, and need to return with it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005) * still held, but drop if for the security compute.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007) * Don't inline this, since it's the slow-path and just
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) * results in a bigger stack frame.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) static noinline
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011) struct avc_node *avc_compute_av(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) u32 ssid, u32 tsid,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) u16 tclass, struct av_decision *avd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014) struct avc_xperms_node *xp_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) INIT_LIST_HEAD(&xp_node->xpd_head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018) security_compute_av(state, ssid, tsid, tclass, avd, &xp_node->xp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) return avc_insert(state->avc, ssid, tsid, tclass, avd, xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) static noinline int avc_denied(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024) u32 ssid, u32 tsid,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1025) u16 tclass, u32 requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1026) u8 driver, u8 xperm, unsigned int flags,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1027) struct av_decision *avd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1028) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1029) if (flags & AVC_STRICT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1030) return -EACCES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1031)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1032) if (enforcing_enabled(state) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1033) !(avd->flags & AVD_FLAGS_PERMISSIVE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1034) return -EACCES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1035)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1036) avc_update_node(state->avc, AVC_CALLBACK_GRANT, requested, driver,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1037) xperm, ssid, tsid, tclass, avd->seqno, NULL, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1038) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1039) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1040)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1041) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1042) * The avc extended permissions logic adds an additional 256 bits of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1043) * permissions to an avc node when extended permissions for that node are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1044) * specified in the avtab. If the additional 256 permissions is not adequate,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1045) * as-is the case with ioctls, then multiple may be chained together and the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1046) * driver field is used to specify which set contains the permission.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1047) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1048) int avc_has_extended_perms(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1049) u32 ssid, u32 tsid, u16 tclass, u32 requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1050) u8 driver, u8 xperm, struct common_audit_data *ad)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1051) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1052) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1053) struct av_decision avd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1054) u32 denied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1055) struct extended_perms_decision local_xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1056) struct extended_perms_decision *xpd = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1057) struct extended_perms_data allowed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1058) struct extended_perms_data auditallow;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1059) struct extended_perms_data dontaudit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1060) struct avc_xperms_node local_xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1061) struct avc_xperms_node *xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1062) int rc = 0, rc2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1063)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1064) xp_node = &local_xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1065) if (WARN_ON(!requested))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1066) return -EACCES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1067)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1068) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1069)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1070) node = avc_lookup(state->avc, ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1071) if (unlikely(!node)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1072) node = avc_compute_av(state, ssid, tsid, tclass, &avd, xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1073) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1074) memcpy(&avd, &node->ae.avd, sizeof(avd));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1075) xp_node = node->ae.xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1076) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1077) /* if extended permissions are not defined, only consider av_decision */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1078) if (!xp_node || !xp_node->xp.len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1079) goto decision;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1080)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1081) local_xpd.allowed = &allowed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1082) local_xpd.auditallow = &auditallow;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1083) local_xpd.dontaudit = &dontaudit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1084)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1085) xpd = avc_xperms_decision_lookup(driver, xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1086) if (unlikely(!xpd)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1087) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1088) * Compute the extended_perms_decision only if the driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1089) * is flagged
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1090) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1091) if (!security_xperm_test(xp_node->xp.drivers.p, driver)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1092) avd.allowed &= ~requested;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1093) goto decision;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1094) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1095) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1096) security_compute_xperms_decision(state, ssid, tsid, tclass,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1097) driver, &local_xpd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1098) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1099) avc_update_node(state->avc, AVC_CALLBACK_ADD_XPERMS, requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1100) driver, xperm, ssid, tsid, tclass, avd.seqno,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1101) &local_xpd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1102) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1103) avc_quick_copy_xperms_decision(xperm, &local_xpd, xpd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1104) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1105) xpd = &local_xpd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1107) if (!avc_xperms_has_perm(xpd, xperm, XPERMS_ALLOWED))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1108) avd.allowed &= ~requested;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1110) decision:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1111) denied = requested & ~(avd.allowed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1112) if (unlikely(denied))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1113) rc = avc_denied(state, ssid, tsid, tclass, requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1114) driver, xperm, AVC_EXTENDED_PERMS, &avd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1116) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1118) rc2 = avc_xperms_audit(state, ssid, tsid, tclass, requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1119) &avd, xpd, xperm, rc, ad);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1120) if (rc2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1121) return rc2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1122) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1125) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1126) * avc_has_perm_noaudit - Check permissions but perform no auditing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1127) * @ssid: source security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1128) * @tsid: target security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1129) * @tclass: target security class
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1130) * @requested: requested permissions, interpreted based on @tclass
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1131) * @flags: AVC_STRICT, AVC_NONBLOCKING, or 0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1132) * @avd: access vector decisions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1133) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1134) * Check the AVC to determine whether the @requested permissions are granted
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1135) * for the SID pair (@ssid, @tsid), interpreting the permissions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1136) * based on @tclass, and call the security server on a cache miss to obtain
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1137) * a new decision and add it to the cache. Return a copy of the decisions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1138) * in @avd. Return %0 if all @requested permissions are granted,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1139) * -%EACCES if any permissions are denied, or another -errno upon
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1140) * other errors. This function is typically called by avc_has_perm(),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1141) * but may also be called directly to separate permission checking from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1142) * auditing, e.g. in cases where a lock must be held for the check but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1143) * should be released for the auditing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1144) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1145) inline int avc_has_perm_noaudit(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1146) u32 ssid, u32 tsid,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1147) u16 tclass, u32 requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1148) unsigned int flags,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1149) struct av_decision *avd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1150) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1151) struct avc_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1152) struct avc_xperms_node xp_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1153) int rc = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1154) u32 denied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1156) if (WARN_ON(!requested))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1157) return -EACCES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1159) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1161) node = avc_lookup(state->avc, ssid, tsid, tclass);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1162) if (unlikely(!node))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1163) node = avc_compute_av(state, ssid, tsid, tclass, avd, &xp_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1164) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1165) memcpy(avd, &node->ae.avd, sizeof(*avd));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1167) denied = requested & ~(avd->allowed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1168) if (unlikely(denied))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1169) rc = avc_denied(state, ssid, tsid, tclass, requested, 0, 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1170) flags, avd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1172) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1173) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1174) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1176) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1177) * avc_has_perm - Check permissions and perform any appropriate auditing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1178) * @ssid: source security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1179) * @tsid: target security identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1180) * @tclass: target security class
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1181) * @requested: requested permissions, interpreted based on @tclass
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1182) * @auditdata: auxiliary audit data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1183) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1184) * Check the AVC to determine whether the @requested permissions are granted
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1185) * for the SID pair (@ssid, @tsid), interpreting the permissions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1186) * based on @tclass, and call the security server on a cache miss to obtain
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1187) * a new decision and add it to the cache. Audit the granting or denial of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1188) * permissions in accordance with the policy. Return %0 if all @requested
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1189) * permissions are granted, -%EACCES if any permissions are denied, or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1190) * another -errno upon other errors.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1191) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1192) int avc_has_perm(struct selinux_state *state, u32 ssid, u32 tsid, u16 tclass,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1193) u32 requested, struct common_audit_data *auditdata)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1194) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1195) struct av_decision avd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1196) int rc, rc2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1198) rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested, 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1199) &avd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1201) rc2 = avc_audit(state, ssid, tsid, tclass, requested, &avd, rc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1202) auditdata, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1203) if (rc2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1204) return rc2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1205) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1206) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1207)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1208) int avc_has_perm_flags(struct selinux_state *state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1209) u32 ssid, u32 tsid, u16 tclass, u32 requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1210) struct common_audit_data *auditdata,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1211) int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1212) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1213) struct av_decision avd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1214) int rc, rc2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1215)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1216) rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1217) (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1218) &avd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1219)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1220) rc2 = avc_audit(state, ssid, tsid, tclass, requested, &avd, rc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1221) auditdata, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1222) if (rc2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1223) return rc2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1224) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1225) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1227) u32 avc_policy_seqno(struct selinux_state *state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1228) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1229) return state->avc->avc_cache.latest_notif;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1230) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1232) void avc_disable(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1233) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1234) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1235) * If you are looking at this because you have realized that we are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1236) * not destroying the avc_node_cachep it might be easy to fix, but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1237) * I don't know the memory barrier semantics well enough to know. It's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1238) * possible that some other task dereferenced security_ops when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1239) * it still pointed to selinux operations. If that is the case it's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1240) * possible that it is about to use the avc and is about to need the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1241) * avc_node_cachep. I know I could wrap the security.c security_ops call
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1242) * in an rcu_lock, but seriously, it's not worth it. Instead I just flush
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1243) * the cache and get that memory back.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1244) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1245) if (avc_node_cachep) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1246) avc_flush(selinux_state.avc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1247) /* kmem_cache_destroy(avc_node_cachep); */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1248) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1249) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags