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authorJames Morris <james.l.morris@oracle.com>2015-08-15 13:29:57 +1000
committerJames Morris <james.l.morris@oracle.com>2015-08-15 13:29:57 +1000
commit3e5f206c00f73f535c914eedc8b91f424c5a14ab (patch)
tree209f621fc8a9b84053bb4feda619185e17242982 /security/selinux
parent0e38c35815f50e5a347977d76fb5eb4c3bf020b5 (diff)
parentfda4d578ed0a7e1d116f56a15efea0e4ba78acad (diff)
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Merge branch 'next' of git://git.infradead.org/users/pcmoore/selinux into next
Diffstat (limited to 'security/selinux')
-rw-r--r--security/selinux/avc.c418
-rw-r--r--security/selinux/hooks.c147
-rw-r--r--security/selinux/include/avc.h6
-rw-r--r--security/selinux/include/security.h32
-rw-r--r--security/selinux/ss/avtab.c104
-rw-r--r--security/selinux/ss/avtab.h33
-rw-r--r--security/selinux/ss/conditional.c32
-rw-r--r--security/selinux/ss/conditional.h6
-rw-r--r--security/selinux/ss/policydb.c5
-rw-r--r--security/selinux/ss/services.c213
-rw-r--r--security/selinux/ss/services.h6
11 files changed, 892 insertions, 110 deletions
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 0b122b1421a9..e60c79de13e1 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -22,6 +22,7 @@
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/percpu.h>
+#include <linux/list.h>
#include <net/sock.h>
#include <linux/un.h>
#include <net/af_unix.h>
@@ -48,6 +49,7 @@ struct avc_entry {
u32 tsid;
u16 tclass;
struct av_decision avd;
+ struct avc_xperms_node *xp_node;
};
struct avc_node {
@@ -56,6 +58,16 @@ struct avc_node {
struct rcu_head rhead;
};
+struct avc_xperms_decision_node {
+ struct extended_perms_decision xpd;
+ struct list_head xpd_list; /* list of extended_perms_decision */
+};
+
+struct avc_xperms_node {
+ struct extended_perms xp;
+ struct list_head xpd_head; /* list head of extended_perms_decision */
+};
+
struct avc_cache {
struct hlist_head slots[AVC_CACHE_SLOTS]; /* head for avc_node->list */
spinlock_t slots_lock[AVC_CACHE_SLOTS]; /* lock for writes */
@@ -80,6 +92,9 @@ DEFINE_PER_CPU(struct avc_cache_stats, avc_cache_stats) = { 0 };
static struct avc_cache avc_cache;
static struct avc_callback_node *avc_callbacks;
static struct kmem_cache *avc_node_cachep;
+static struct kmem_cache *avc_xperms_data_cachep;
+static struct kmem_cache *avc_xperms_decision_cachep;
+static struct kmem_cache *avc_xperms_cachep;
static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass)
{
@@ -101,6 +116,7 @@ static void avc_dump_av(struct audit_buffer *ab, u16 tclass, u32 av)
return;
}
+ BUG_ON(!tclass || tclass >= ARRAY_SIZE(secclass_map));
perms = secclass_map[tclass-1].perms;
audit_log_format(ab, " {");
@@ -149,7 +165,7 @@ static void avc_dump_query(struct audit_buffer *ab, u32 ssid, u32 tsid, u16 tcla
kfree(scontext);
}
- BUG_ON(tclass >= ARRAY_SIZE(secclass_map));
+ BUG_ON(!tclass || tclass >= ARRAY_SIZE(secclass_map));
audit_log_format(ab, " tclass=%s", secclass_map[tclass-1].name);
}
@@ -170,7 +186,17 @@ void __init avc_init(void)
atomic_set(&avc_cache.lru_hint, 0);
avc_node_cachep = kmem_cache_create("avc_node", sizeof(struct avc_node),
- 0, SLAB_PANIC, NULL);
+ 0, SLAB_PANIC, NULL);
+ avc_xperms_cachep = kmem_cache_create("avc_xperms_node",
+ sizeof(struct avc_xperms_node),
+ 0, SLAB_PANIC, NULL);
+ avc_xperms_decision_cachep = kmem_cache_create(
+ "avc_xperms_decision_node",
+ sizeof(struct avc_xperms_decision_node),
+ 0, SLAB_PANIC, NULL);
+ avc_xperms_data_cachep = kmem_cache_create("avc_xperms_data",
+ sizeof(struct extended_perms_data),
+ 0, SLAB_PANIC, NULL);
audit_log(current->audit_context, GFP_KERNEL, AUDIT_KERNEL, "AVC INITIALIZED\n");
}
@@ -205,9 +231,261 @@ int avc_get_hash_stats(char *page)
slots_used, AVC_CACHE_SLOTS, max_chain_len);
}
+/*
+ * using a linked list for extended_perms_decision lookup because the list is
+ * always small. i.e. less than 5, typically 1
+ */
+static struct extended_perms_decision *avc_xperms_decision_lookup(u8 driver,
+ struct avc_xperms_node *xp_node)
+{
+ struct avc_xperms_decision_node *xpd_node;
+
+ list_for_each_entry(xpd_node, &xp_node->xpd_head, xpd_list) {
+ if (xpd_node->xpd.driver == driver)
+ return &xpd_node->xpd;
+ }
+ return NULL;
+}
+
+static inline unsigned int
+avc_xperms_has_perm(struct extended_perms_decision *xpd,
+ u8 perm, u8 which)
+{
+ unsigned int rc = 0;
+
+ if ((which == XPERMS_ALLOWED) &&
+ (xpd->used & XPERMS_ALLOWED))
+ rc = security_xperm_test(xpd->allowed->p, perm);
+ else if ((which == XPERMS_AUDITALLOW) &&
+ (xpd->used & XPERMS_AUDITALLOW))
+ rc = security_xperm_test(xpd->auditallow->p, perm);
+ else if ((which == XPERMS_DONTAUDIT) &&
+ (xpd->used & XPERMS_DONTAUDIT))
+ rc = security_xperm_test(xpd->dontaudit->p, perm);
+ return rc;
+}
+
+static void avc_xperms_allow_perm(struct avc_xperms_node *xp_node,
+ u8 driver, u8 perm)
+{
+ struct extended_perms_decision *xpd;
+ security_xperm_set(xp_node->xp.drivers.p, driver);
+ xpd = avc_xperms_decision_lookup(driver, xp_node);
+ if (xpd && xpd->allowed)
+ security_xperm_set(xpd->allowed->p, perm);
+}
+
+static void avc_xperms_decision_free(struct avc_xperms_decision_node *xpd_node)
+{
+ struct extended_perms_decision *xpd;
+
+ xpd = &xpd_node->xpd;
+ if (xpd->allowed)
+ kmem_cache_free(avc_xperms_data_cachep, xpd->allowed);
+ if (xpd->auditallow)
+ kmem_cache_free(avc_xperms_data_cachep, xpd->auditallow);
+ if (xpd->dontaudit)
+ kmem_cache_free(avc_xperms_data_cachep, xpd->dontaudit);
+ kmem_cache_free(avc_xperms_decision_cachep, xpd_node);
+}
+
+static void avc_xperms_free(struct avc_xperms_node *xp_node)
+{
+ struct avc_xperms_decision_node *xpd_node, *tmp;
+
+ if (!xp_node)
+ return;
+
+ list_for_each_entry_safe(xpd_node, tmp, &xp_node->xpd_head, xpd_list) {
+ list_del(&xpd_node->xpd_list);
+ avc_xperms_decision_free(xpd_node);
+ }
+ kmem_cache_free(avc_xperms_cachep, xp_node);
+}
+
+static void avc_copy_xperms_decision(struct extended_perms_decision *dest,
+ struct extended_perms_decision *src)
+{
+ dest->driver = src->driver;
+ dest->used = src->used;
+ if (dest->used & XPERMS_ALLOWED)
+ memcpy(dest->allowed->p, src->allowed->p,
+ sizeof(src->allowed->p));
+ if (dest->used & XPERMS_AUDITALLOW)
+ memcpy(dest->auditallow->p, src->auditallow->p,
+ sizeof(src->auditallow->p));
+ if (dest->used & XPERMS_DONTAUDIT)
+ memcpy(dest->dontaudit->p, src->dontaudit->p,
+ sizeof(src->dontaudit->p));
+}
+
+/*
+ * similar to avc_copy_xperms_decision, but only copy decision
+ * information relevant to this perm
+ */
+static inline void avc_quick_copy_xperms_decision(u8 perm,
+ struct extended_perms_decision *dest,
+ struct extended_perms_decision *src)
+{
+ /*
+ * compute index of the u32 of the 256 bits (8 u32s) that contain this
+ * command permission
+ */
+ u8 i = perm >> 5;
+
+ dest->used = src->used;
+ if (dest->used & XPERMS_ALLOWED)
+ dest->allowed->p[i] = src->allowed->p[i];
+ if (dest->used & XPERMS_AUDITALLOW)
+ dest->auditallow->p[i] = src->auditallow->p[i];
+ if (dest->used & XPERMS_DONTAUDIT)
+ dest->dontaudit->p[i] = src->dontaudit->p[i];
+}
+
+static struct avc_xperms_decision_node
+ *avc_xperms_decision_alloc(u8 which)
+{
+ struct avc_xperms_decision_node *xpd_node;
+ struct extended_perms_decision *xpd;
+
+ xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep,
+ GFP_ATOMIC | __GFP_NOMEMALLOC);
+ if (!xpd_node)
+ return NULL;
+
+ xpd = &xpd_node->xpd;
+ if (which & XPERMS_ALLOWED) {
+ xpd->allowed = kmem_cache_zalloc(avc_xperms_data_cachep,
+ GFP_ATOMIC | __GFP_NOMEMALLOC);
+ if (!xpd->allowed)
+ goto error;
+ }
+ if (which & XPERMS_AUDITALLOW) {
+ xpd->auditallow = kmem_cache_zalloc(avc_xperms_data_cachep,
+ GFP_ATOMIC | __GFP_NOMEMALLOC);
+ if (!xpd->auditallow)
+ goto error;
+ }
+ if (which & XPERMS_DONTAUDIT) {
+ xpd->dontaudit = kmem_cache_zalloc(avc_xperms_data_cachep,
+ GFP_ATOMIC | __GFP_NOMEMALLOC);
+ if (!xpd->dontaudit)
+ goto error;
+ }
+ return xpd_node;
+error:
+ avc_xperms_decision_free(xpd_node);
+ return NULL;
+}
+
+static int avc_add_xperms_decision(struct avc_node *node,
+ struct extended_perms_decision *src)
+{
+ struct avc_xperms_decision_node *dest_xpd;
+
+ node->ae.xp_node->xp.len++;
+ dest_xpd = avc_xperms_decision_alloc(src->used);
+ if (!dest_xpd)
+ return -ENOMEM;
+ avc_copy_xperms_decision(&dest_xpd->xpd, src);
+ list_add(&dest_xpd->xpd_list, &node->ae.xp_node->xpd_head);
+ return 0;
+}
+
+static struct avc_xperms_node *avc_xperms_alloc(void)
+{
+ struct avc_xperms_node *xp_node;
+
+ xp_node = kmem_cache_zalloc(avc_xperms_cachep,
+ GFP_ATOMIC|__GFP_NOMEMALLOC);
+ if (!xp_node)
+ return xp_node;
+ INIT_LIST_HEAD(&xp_node->xpd_head);
+ return xp_node;
+}
+
+static int avc_xperms_populate(struct avc_node *node,
+ struct avc_xperms_node *src)
+{
+ struct avc_xperms_node *dest;
+ struct avc_xperms_decision_node *dest_xpd;
+ struct avc_xperms_decision_node *src_xpd;
+
+ if (src->xp.len == 0)
+ return 0;
+ dest = avc_xperms_alloc();
+ if (!dest)
+ return -ENOMEM;
+
+ memcpy(dest->xp.drivers.p, src->xp.drivers.p, sizeof(dest->xp.drivers.p));
+ dest->xp.len = src->xp.len;
+
+ /* for each source xpd allocate a destination xpd and copy */
+ list_for_each_entry(src_xpd, &src->xpd_head, xpd_list) {
+ dest_xpd = avc_xperms_decision_alloc(src_xpd->xpd.used);
+ if (!dest_xpd)
+ goto error;
+ avc_copy_xperms_decision(&dest_xpd->xpd, &src_xpd->xpd);
+ list_add(&dest_xpd->xpd_list, &dest->xpd_head);
+ }
+ node->ae.xp_node = dest;
+ return 0;
+error:
+ avc_xperms_free(dest);
+ return -ENOMEM;
+
+}
+
+static inline u32 avc_xperms_audit_required(u32 requested,
+ struct av_decision *avd,
+ struct extended_perms_decision *xpd,
+ u8 perm,
+ int result,
+ u32 *deniedp)
+{
+ u32 denied, audited;
+
+ denied = requested & ~avd->allowed;
+ if (unlikely(denied)) {
+ audited = denied & avd->auditdeny;
+ if (audited && xpd) {
+ if (avc_xperms_has_perm(xpd, perm, XPERMS_DONTAUDIT))
+ audited &= ~requested;
+ }
+ } else if (result) {
+ audited = denied = requested;
+ } else {
+ audited = requested & avd->auditallow;
+ if (audited && xpd) {
+ if (!avc_xperms_has_perm(xpd, perm, XPERMS_AUDITALLOW))
+ audited &= ~requested;
+ }
+ }
+
+ *deniedp = denied;
+ return audited;
+}
+
+static inline int avc_xperms_audit(u32 ssid, u32 tsid, u16 tclass,
+ u32 requested, struct av_decision *avd,
+ struct extended_perms_decision *xpd,
+ u8 perm, int result,
+ struct common_audit_data *ad)
+{
+ u32 audited, denied;
+
+ audited = avc_xperms_audit_required(
+ requested, avd, xpd, perm, result, &denied);
+ if (likely(!audited))
+ return 0;
+ return slow_avc_audit(ssid, tsid, tclass, requested,
+ audited, denied, result, ad, 0);
+}
+
static void avc_node_free(struct rcu_head *rhead)
{
struct avc_node *node = container_of(rhead, struct avc_node, rhead);
+ avc_xperms_free(node->ae.xp_node);
kmem_cache_free(avc_node_cachep, node);
avc_cache_stats_incr(frees);
}
@@ -221,6 +499,7 @@ static void avc_node_delete(struct avc_node *node)
static void avc_node_kill(struct avc_node *node)
{
+ avc_xperms_free(node->ae.xp_node);
kmem_cache_free(avc_node_cachep, node);
avc_cache_stats_incr(frees);
atomic_dec(&avc_cache.active_nodes);
@@ -367,6 +646,7 @@ static int avc_latest_notif_update(int seqno, int is_insert)
* @tsid: target security identifier
* @tclass: target security class
* @avd: resulting av decision
+ * @xp_node: resulting extended permissions
*
* Insert an AVC entry for the SID pair
* (@ssid, @tsid) and class @tclass.
@@ -378,7 +658,9 @@ static int avc_latest_notif_update(int seqno, int is_insert)
* the access vectors into a cache entry, returns
* avc_node inserted. Otherwise, this function returns NULL.
*/
-static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass, struct av_decision *avd)
+static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass,
+ struct av_decision *avd,
+ struct avc_xperms_node *xp_node)
{
struct avc_node *pos, *node = NULL;
int hvalue;
@@ -391,10 +673,15 @@ static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass, struct av_dec
if (node) {
struct hlist_head *head;
spinlock_t *lock;
+ int rc = 0;
hvalue = avc_hash(ssid, tsid, tclass);
avc_node_populate(node, ssid, tsid, tclass, avd);
-
+ rc = avc_xperms_populate(node, xp_node);
+ if (rc) {
+ kmem_cache_free(avc_node_cachep, node);
+ return NULL;
+ }
head = &avc_cache.slots[hvalue];
lock = &avc_cache.slots_lock[hvalue];
@@ -523,14 +810,17 @@ out:
* @perms : Permission mask bits
* @ssid,@tsid,@tclass : identifier of an AVC entry
* @seqno : sequence number when decision was made
+ * @xpd: extended_perms_decision to be added to the node
*
* if a valid AVC entry doesn't exist,this function returns -ENOENT.
* if kmalloc() called internal returns NULL, this function returns -ENOMEM.
* otherwise, this function updates the AVC entry. The original AVC-entry object
* will release later by RCU.
*/
-static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass,
- u32 seqno)
+static int avc_update_node(u32 event, u32 perms, u8 driver, u8 xperm, u32 ssid,
+ u32 tsid, u16 tclass, u32 seqno,
+ struct extended_perms_decision *xpd,
+ u32 flags)
{
int hvalue, rc = 0;
unsigned long flag;
@@ -574,9 +864,19 @@ static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass,
avc_node_populate(node, ssid, tsid, tclass, &orig->ae.avd);
+ if (orig->ae.xp_node) {
+ rc = avc_xperms_populate(node, orig->ae.xp_node);
+ if (rc) {
+ kmem_cache_free(avc_node_cachep, node);
+ goto out_unlock;
+ }
+ }
+
switch (event) {
case AVC_CALLBACK_GRANT:
node->ae.avd.allowed |= perms;
+ if (node->ae.xp_node && (flags & AVC_EXTENDED_PERMS))
+ avc_xperms_allow_perm(node->ae.xp_node, driver, xperm);
break;
case AVC_CALLBACK_TRY_REVOKE:
case AVC_CALLBACK_REVOKE:
@@ -594,6 +894,9 @@ static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass,
case AVC_CALLBACK_AUDITDENY_DISABLE:
node->ae.avd.auditdeny &= ~perms;
break;
+ case AVC_CALLBACK_ADD_XPERMS:
+ avc_add_xperms_decision(node, xpd);
+ break;
}
avc_node_replace(node, orig);
out_unlock:
@@ -665,18 +968,20 @@ int avc_ss_reset(u32 seqno)
* results in a bigger stack frame.
*/
static noinline struct avc_node *avc_compute_av(u32 ssid, u32 tsid,
- u16 tclass, struct av_decision *avd)
+ u16 tclass, struct av_decision *avd,
+ struct avc_xperms_node *xp_node)
{
rcu_read_unlock();
- security_compute_av(ssid, tsid, tclass, avd);
+ INIT_LIST_HEAD(&xp_node->xpd_head);
+ security_compute_av(ssid, tsid, tclass, avd, &xp_node->xp);
rcu_read_lock();
- return avc_insert(ssid, tsid, tclass, avd);
+ return avc_insert(ssid, tsid, tclass, avd, xp_node);
}
static noinline int avc_denied(u32 ssid, u32 tsid,
- u16 tclass, u32 requested,
- unsigned flags,
- struct av_decision *avd)
+ u16 tclass, u32 requested,
+ u8 driver, u8 xperm, unsigned flags,
+ struct av_decision *avd)
{
if (flags & AVC_STRICT)
return -EACCES;
@@ -684,11 +989,91 @@ static noinline int avc_denied(u32 ssid, u32 tsid,
if (selinux_enforcing && !(avd->flags & AVD_FLAGS_PERMISSIVE))
return -EACCES;
- avc_update_node(AVC_CALLBACK_GRANT, requested, ssid,
- tsid, tclass, avd->seqno);
+ avc_update_node(AVC_CALLBACK_GRANT, requested, driver, xperm, ssid,
+ tsid, tclass, avd->seqno, NULL, flags);
return 0;
}
+/*
+ * The avc extended permissions logic adds an additional 256 bits of
+ * permissions to an avc node when extended permissions for that node are
+ * specified in the avtab. If the additional 256 permissions is not adequate,
+ * as-is the case with ioctls, then multiple may be chained together and the
+ * driver field is used to specify which set contains the permission.
+ */
+int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested,
+ u8 driver, u8 xperm, struct common_audit_data *ad)
+{
+ struct avc_node *node;
+ struct av_decision avd;
+ u32 denied;
+ struct extended_perms_decision local_xpd;
+ struct extended_perms_decision *xpd = NULL;
+ struct extended_perms_data allowed;
+ struct extended_perms_data auditallow;
+ struct extended_perms_data dontaudit;
+ struct avc_xperms_node local_xp_node;
+ struct avc_xperms_node *xp_node;
+ int rc = 0, rc2;
+
+ xp_node = &local_xp_node;
+ BUG_ON(!requested);
+
+ rcu_read_lock();
+
+ node = avc_lookup(ssid, tsid, tclass);
+ if (unlikely(!node)) {
+ node = avc_compute_av(ssid, tsid, tclass, &avd, xp_node);
+ } else {
+ memcpy(&avd, &node->ae.avd, sizeof(avd));
+ xp_node = node->ae.xp_node;
+ }
+ /* if extended permissions are not defined, only consider av_decision */
+ if (!xp_node || !xp_node->xp.len)
+ goto decision;
+
+ local_xpd.allowed = &allowed;
+ local_xpd.auditallow = &auditallow;
+ local_xpd.dontaudit = &dontaudit;
+
+ xpd = avc_xperms_decision_lookup(driver, xp_node);
+ if (unlikely(!xpd)) {
+ /*
+ * Compute the extended_perms_decision only if the driver
+ * is flagged
+ */
+ if (!security_xperm_test(xp_node->xp.drivers.p, driver)) {
+ avd.allowed &= ~requested;
+ goto decision;
+ }
+ rcu_read_unlock();
+ security_compute_xperms_decision(ssid, tsid, tclass, driver,
+ &local_xpd);
+ rcu_read_lock();
+ avc_update_node(AVC_CALLBACK_ADD_XPERMS, requested, driver, xperm,
+ ssid, tsid, tclass, avd.seqno, &local_xpd, 0);
+ } else {
+ avc_quick_copy_xperms_decision(xperm, &local_xpd, xpd);
+ }
+ xpd = &local_xpd;
+
+ if (!avc_xperms_has_perm(xpd, xperm, XPERMS_ALLOWED))
+ avd.allowed &= ~requested;
+
+decision:
+ denied = requested & ~(avd.allowed);
+ if (unlikely(denied))
+ rc = avc_denied(ssid, tsid, tclass, requested, driver, xperm,
+ AVC_EXTENDED_PERMS, &avd);
+
+ rcu_read_unlock();
+
+ rc2 = avc_xperms_audit(ssid, tsid, tclass, requested,
+ &avd, xpd, xperm, rc, ad);
+ if (rc2)
+ return rc2;
+ return rc;
+}
/**
* avc_has_perm_noaudit - Check permissions but perform no auditing.
@@ -716,6 +1101,7 @@ inline int avc_has_perm_noaudit(u32 ssid, u32 tsid,
struct av_decision *avd)
{
struct avc_node *node;
+ struct avc_xperms_node xp_node;
int rc = 0;
u32 denied;
@@ -725,13 +1111,13 @@ inline int avc_has_perm_noaudit(u32 ssid, u32 tsid,
node = avc_lookup(ssid, tsid, tclass);
if (unlikely(!node))
- node = avc_compute_av(ssid, tsid, tclass, avd);
+ node = avc_compute_av(ssid, tsid, tclass, avd, &xp_node);
else
memcpy(avd, &node->ae.avd, sizeof(*avd));
denied = requested & ~(avd->allowed);
if (unlikely(denied))
- rc = avc_denied(ssid, tsid, tclass, requested, flags, avd);
+ rc = avc_denied(ssid, tsid, tclass, requested, 0, 0, flags, avd);
rcu_read_unlock();
return rc;
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 564079c5c49d..55285054aa73 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -254,10 +254,21 @@ static void inode_free_security(struct inode *inode)
struct inode_security_struct *isec = inode->i_security;
struct superblock_security_struct *sbsec = inode->i_sb->s_security;
- spin_lock(&sbsec->isec_lock);
- if (!list_empty(&isec->list))
+ /*
+ * As not all inode security structures are in a list, we check for
+ * empty list outside of the lock to make sure that we won't waste
+ * time taking a lock doing nothing.
+ *
+ * The list_del_init() function can be safely called more than once.
+ * It should not be possible for this function to be called with
+ * concurrent list_add(), but for better safety against future changes
+ * in the code, we use list_empty_careful() here.
+ */
+ if (!list_empty_careful(&isec->list)) {
+ spin_lock(&sbsec->isec_lock);
list_del_init(&isec->list);
- spin_unlock(&sbsec->isec_lock);
+ spin_unlock(&sbsec->isec_lock);
+ }
/*
* The inode may still be referenced in a path walk and
@@ -1698,6 +1709,32 @@ out:
return rc;
}
+/*
+ * Determine the label for an inode that might be unioned.
+ */
+static int selinux_determine_inode_label(const struct inode *dir,
+ const struct qstr *name,
+ u16 tclass,
+ u32 *_new_isid)
+{
+ const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
+ const struct inode_security_struct *dsec = dir->i_security;
+ const struct task_security_struct *tsec = current_security();
+
+ if ((sbsec->flags & SE_SBINITIALIZED) &&
+ (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
+ *_new_isid = sbsec->mntpoint_sid;
+ } else if ((sbsec->flags & SBLABEL_MNT) &&
+ tsec->create_sid) {
+ *_new_isid = tsec->create_sid;
+ } else {
+ return security_transition_sid(tsec->sid, dsec->sid, tclass,
+ name, _new_isid);
+ }
+
+ return 0;
+}
+
/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
struct dentry *dentry,
@@ -1714,7 +1751,6 @@ static int may_create(struct inode *dir,
sbsec = dir->i_sb->s_security;
sid = tsec->sid;
- newsid = tsec->create_sid;
ad.type = LSM_AUDIT_DATA_DENTRY;
ad.u.dentry = dentry;
@@ -1725,12 +1761,10 @@ static int may_create(struct inode *dir,
if (rc)
return rc;
- if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
- rc = security_transition_sid(sid, dsec->sid, tclass,
- &dentry->d_name, &newsid);
- if (rc)
- return rc;
- }
+ rc = selinux_determine_inode_label(dir, &dentry->d_name, tclass,
+ &newsid);
+ if (rc)
+ return rc;
rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
if (rc)
@@ -2704,32 +2738,14 @@ static int selinux_dentry_init_security(struct dentry *dentry, int mode,
struct qstr *name, void **ctx,
u32 *ctxlen)
{
- const struct cred *cred = current_cred();
- struct task_security_struct *tsec;
- struct inode_security_struct *dsec;
- struct superblock_security_struct *sbsec;
- struct inode *dir = d_backing_inode(dentry->d_parent);
u32 newsid;
int rc;
- tsec = cred->security;
- dsec = dir->i_security;
- sbsec = dir->i_sb->s_security;
-
- if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
- newsid = tsec->create_sid;
- } else {
- rc = security_transition_sid(tsec->sid, dsec->sid,
- inode_mode_to_security_class(mode),
- name,
- &newsid);
- if (rc) {
- printk(KERN_WARNING
- "%s: security_transition_sid failed, rc=%d\n",
- __func__, -rc);
- return rc;
- }
- }
+ rc = selinux_determine_inode_label(d_inode(dentry->d_parent), name,
+ inode_mode_to_security_class(mode),
+ &newsid);
+ if (rc)
+ return rc;
return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}
@@ -2752,22 +2768,12 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
sid = tsec->sid;
newsid = tsec->create_sid;
- if ((sbsec->flags & SE_SBINITIALIZED) &&
- (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
- newsid = sbsec->mntpoint_sid;
- else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
- rc = security_transition_sid(sid, dsec->sid,
- inode_mode_to_security_class(inode->i_mode),
- qstr, &newsid);
- if (rc) {
- printk(KERN_WARNING "%s: "
- "security_transition_sid failed, rc=%d (dev=%s "
- "ino=%ld)\n",
- __func__,
- -rc, inode->i_sb->s_id, inode->i_ino);
- return rc;
- }
- }
+ rc = selinux_determine_inode_label(
+ dir, qstr,
+ inode_mode_to_security_class(inode->i_mode),
+ &newsid);
+ if (rc)
+ return rc;
/* Possibly defer initialization to selinux_complete_init. */
if (sbsec->flags & SE_SBINITIALIZED) {
@@ -3228,6 +3234,46 @@ static void selinux_file_free_security(struct file *file)
file_free_security(file);
}
+/*
+ * Check whether a task has the ioctl permission and cmd
+ * operation to an inode.
+ */
+int ioctl_has_perm(const struct cred *cred, struct file *file,
+ u32 requested, u16 cmd)
+{
+ struct common_audit_data ad;
+ struct file_security_struct *fsec = file->f_security;
+ struct inode *inode = file_inode(file);
+ struct inode_security_struct *isec = inode->i_security;
+ struct lsm_ioctlop_audit ioctl;
+ u32 ssid = cred_sid(cred);
+ int rc;
+ u8 driver = cmd >> 8;
+ u8 xperm = cmd & 0xff;
+
+ ad.type = LSM_AUDIT_DATA_IOCTL_OP;
+ ad.u.op = &ioctl;
+ ad.u.op->cmd = cmd;
+ ad.u.op->path = file->f_path;
+
+ if (ssid != fsec->sid) {
+ rc = avc_has_perm(ssid, fsec->sid,
+ SECCLASS_FD,
+ FD__USE,
+ &ad);
+ if (rc)
+ goto out;
+ }
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return 0;
+
+ rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
+ requested, driver, xperm, &ad);
+out:
+ return rc;
+}
+
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
@@ -3270,7 +3316,7 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd,
* to the file's ioctl() function.
*/
default:
- error = file_has_perm(cred, file, FILE__IOCTL);
+ error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
}
return error;
}
@@ -4520,6 +4566,7 @@ static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority
sksec->peer_sid = SECINITSID_UNLABELED;
sksec->sid = SECINITSID_UNLABELED;
+ sksec->sclass = SECCLASS_SOCKET;
selinux_netlbl_sk_security_reset(sksec);
sk->sk_security = sksec;
diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h
index 5973c327c54e..0999df03af8b 100644
--- a/security/selinux/include/avc.h
+++ b/security/selinux/include/avc.h
@@ -143,6 +143,7 @@ static inline int avc_audit(u32 ssid, u32 tsid,
}
#define AVC_STRICT 1 /* Ignore permissive mode. */
+#define AVC_EXTENDED_PERMS 2 /* update extended permissions */
int avc_has_perm_noaudit(u32 ssid, u32 tsid,
u16 tclass, u32 requested,
unsigned flags,
@@ -156,6 +157,10 @@ int avc_has_perm_flags(u32 ssid, u32 tsid,
struct common_audit_data *auditdata,
int flags);
+int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested,
+ u8 driver, u8 perm, struct common_audit_data *ad);
+
+
u32 avc_policy_seqno(void);
#define AVC_CALLBACK_GRANT 1
@@ -166,6 +171,7 @@ u32 avc_policy_seqno(void);
#define AVC_CALLBACK_AUDITALLOW_DISABLE 32
#define AVC_CALLBACK_AUDITDENY_ENABLE 64
#define AVC_CALLBACK_AUDITDENY_DISABLE 128
+#define AVC_CALLBACK_ADD_XPERMS 256
int avc_add_callback(int (*callback)(u32 event), u32 events);
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 36993ad1c067..6a681d26bf20 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -35,13 +35,14 @@
#define POLICYDB_VERSION_NEW_OBJECT_DEFAULTS 27
#define POLICYDB_VERSION_DEFAULT_TYPE 28
#define POLICYDB_VERSION_CONSTRAINT_NAMES 29
+#define POLICYDB_VERSION_XPERMS_IOCTL 30
/* Range of policy versions we understand*/
#define POLICYDB_VERSION_MIN POLICYDB_VERSION_BASE
#ifdef CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX
#define POLICYDB_VERSION_MAX CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX_VALUE
#else
-#define POLICYDB_VERSION_MAX POLICYDB_VERSION_CONSTRAINT_NAMES
+#define POLICYDB_VERSION_MAX POLICYDB_VERSION_XPERMS_IOCTL
#endif
/* Mask for just the mount related flags */
@@ -109,11 +110,38 @@ struct av_decision {
u32 flags;
};
+#define XPERMS_ALLOWED 1
+#define XPERMS_AUDITALLOW 2
+#define XPERMS_DONTAUDIT 4
+
+#define security_xperm_set(perms, x) (perms[x >> 5] |= 1 << (x & 0x1f))
+#define security_xperm_test(perms, x) (1 & (perms[x >> 5] >> (x & 0x1f)))
+struct extended_perms_data {
+ u32 p[8];
+};
+
+struct extended_perms_decision {
+ u8 used;
+ u8 driver;
+ struct extended_perms_data *allowed;
+ struct extended_perms_data *auditallow;
+ struct extended_perms_data *dontaudit;
+};
+
+struct extended_perms {
+ u16 len; /* length associated decision chain */
+ struct extended_perms_data drivers; /* flag drivers that are used */
+};
+
/* definitions of av_decision.flags */
#define AVD_FLAGS_PERMISSIVE 0x0001
void security_compute_av(u32 ssid, u32 tsid,
- u16 tclass, struct av_decision *avd);
+ u16 tclass, struct av_decision *avd,
+ struct extended_perms *xperms);
+
+void security_compute_xperms_decision(u32 ssid, u32 tsid, u16 tclass,
+ u8 driver, struct extended_perms_decision *xpermd);
void security_compute_av_user(u32 ssid, u32 tsid,
u16 tclass, struct av_decision *avd);
diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
index b64f2772b030..3628d3a868b6 100644
--- a/security/selinux/ss/avtab.c
+++ b/security/selinux/ss/avtab.c
@@ -24,6 +24,7 @@
#include "policydb.h"
static struct kmem_cache *avtab_node_cachep;
+static struct kmem_cache *avtab_xperms_cachep;
/* Based on MurmurHash3, written by Austin Appleby and placed in the
* public domain.
@@ -70,11 +71,24 @@ avtab_insert_node(struct avtab *h, int hvalue,
struct avtab_key *key, struct avtab_datum *datum)
{
struct avtab_node *newnode;
+ struct avtab_extended_perms *xperms;
newnode = kmem_cache_zalloc(avtab_node_cachep, GFP_KERNEL);
if (newnode == NULL)
return NULL;
newnode->key = *key;
- newnode->datum = *datum;
+
+ if (key->specified & AVTAB_XPERMS) {
+ xperms = kmem_cache_zalloc(avtab_xperms_cachep, GFP_KERNEL);
+ if (xperms == NULL) {
+ kmem_cache_free(avtab_node_cachep, newnode);
+ return NULL;
+ }
+ *xperms = *(datum->u.xperms);
+ newnode->datum.u.xperms = xperms;
+ } else {
+ newnode->datum.u.data = datum->u.data;
+ }
+
if (prev) {
newnode->next = prev->next;
prev->next = newnode;
@@ -107,8 +121,12 @@ static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_dat
if (key->source_type == cur->key.source_type &&
key->target_type == cur->key.target_type &&
key->target_class == cur->key.target_class &&
- (specified & cur->key.specified))
+ (specified & cur->key.specified)) {
+ /* extended perms may not be unique */
+ if (specified & AVTAB_XPERMS)
+ break;
return -EEXIST;
+ }
if (key->source_type < cur->key.source_type)
break;
if (key->source_type == cur->key.source_type &&
@@ -271,6 +289,9 @@ void avtab_destroy(struct avtab *h)
while (cur) {