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Diffstat (limited to 'security/selinux/ss/avtab.c')
-rw-r--r--security/selinux/ss/avtab.c159
1 files changed, 144 insertions, 15 deletions
diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
index a3dd9faa19c0..640c16b9d3fb 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;
static inline int avtab_hash(struct avtab_key *keyp, u16 mask)
{
@@ -37,11 +38,24 @@ 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;
@@ -70,8 +84,12 @@ 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 &&
@@ -232,6 +250,9 @@ void avtab_destroy(struct avtab *h)
while (cur) {
temp = cur;
cur = cur->next;
+ if (temp->key.specified & AVTAB_XPERMS)
+ kmem_cache_free(avtab_xperms_cachep,
+ temp->datum.u.xperms);
kmem_cache_free(avtab_node_cachep, temp);
}
h->htable[i] = NULL;
@@ -314,13 +335,42 @@ void avtab_hash_eval(struct avtab *h, char *tag)
chain2_len_sum);
}
+/*
+ * extended permissions compatibility. Make ToT Android kernels compatible
+ * with Android M releases
+ */
+#define AVTAB_OPTYPE_ALLOWED 0x1000
+#define AVTAB_OPTYPE_AUDITALLOW 0x2000
+#define AVTAB_OPTYPE_DONTAUDIT 0x4000
+#define AVTAB_OPTYPE (AVTAB_OPTYPE_ALLOWED | \
+ AVTAB_OPTYPE_AUDITALLOW | \
+ AVTAB_OPTYPE_DONTAUDIT)
+#define AVTAB_XPERMS_OPTYPE 4
+
+#define avtab_xperms_to_optype(x) (x << AVTAB_XPERMS_OPTYPE)
+#define avtab_optype_to_xperms(x) (x >> AVTAB_XPERMS_OPTYPE)
+
+static unsigned int avtab_android_m_compat;
+
+static void avtab_android_m_compat_set(void)
+{
+ if (!avtab_android_m_compat) {
+ pr_info("SELinux: Android master kernel running Android"
+ " M policy in compatibility mode.\n");
+ avtab_android_m_compat = 1;
+ }
+}
+
static uint16_t spec_order[] = {
AVTAB_ALLOWED,
AVTAB_AUDITDENY,
AVTAB_AUDITALLOW,
AVTAB_TRANSITION,
AVTAB_CHANGE,
- AVTAB_MEMBER
+ AVTAB_MEMBER,
+ AVTAB_XPERMS_ALLOWED,
+ AVTAB_XPERMS_AUDITALLOW,
+ AVTAB_XPERMS_DONTAUDIT
};
int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
@@ -330,10 +380,12 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
{
__le16 buf16[4];
u16 enabled;
- __le32 buf32[7];
u32 items, items2, val, vers = pol->policyvers;
struct avtab_key key;
struct avtab_datum datum;
+ struct avtab_extended_perms xperms;
+ __le32 buf32[ARRAY_SIZE(xperms.perms.p)];
+ unsigned int android_m_compat_optype = 0;
int i, rc;
unsigned set;
@@ -390,11 +442,15 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
printk(KERN_ERR "SELinux: avtab: entry has both access vectors and types\n");
return -EINVAL;
}
+ if (val & AVTAB_XPERMS) {
+ printk(KERN_ERR "SELinux: avtab: entry has extended permissions\n");
+ return -EINVAL;
+ }
for (i = 0; i < ARRAY_SIZE(spec_order); i++) {
if (val & spec_order[i]) {
key.specified = spec_order[i] | enabled;
- datum.data = le32_to_cpu(buf32[items++]);
+ datum.u.data = le32_to_cpu(buf32[items++]);
rc = insertf(a, &key, &datum, p);
if (rc)
return rc;
@@ -420,6 +476,13 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
key.target_class = le16_to_cpu(buf16[items++]);
key.specified = le16_to_cpu(buf16[items++]);
+ if ((key.specified & AVTAB_OPTYPE) &&
+ (vers == POLICYDB_VERSION_XPERMS_IOCTL)) {
+ key.specified = avtab_optype_to_xperms(key.specified);
+ android_m_compat_optype = 1;
+ avtab_android_m_compat_set();
+ }
+
if (!policydb_type_isvalid(pol, key.source_type) ||
!policydb_type_isvalid(pol, key.target_type) ||
!policydb_class_isvalid(pol, key.target_class)) {
@@ -437,14 +500,54 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
return -EINVAL;
}
- rc = next_entry(buf32, fp, sizeof(u32));
- if (rc) {
- printk(KERN_ERR "SELinux: avtab: truncated entry\n");
- return rc;
+ if ((vers < POLICYDB_VERSION_XPERMS_IOCTL) &&
+ (key.specified & AVTAB_XPERMS)) {
+ printk(KERN_ERR "SELinux: avtab: policy version %u does not "
+ "support extended permissions rules and one "
+ "was specified\n", vers);
+ return -EINVAL;
+ } else if (key.specified & AVTAB_XPERMS) {
+ memset(&xperms, 0, sizeof(struct avtab_extended_perms));
+ rc = next_entry(&xperms.specified, fp, sizeof(u8));
+ if (rc) {
+ printk(KERN_ERR "SELinux: avtab: truncated entry\n");
+ return rc;
+ }
+ if (avtab_android_m_compat ||
+ ((xperms.specified != AVTAB_XPERMS_IOCTLFUNCTION) &&
+ (xperms.specified != AVTAB_XPERMS_IOCTLDRIVER) &&
+ (vers == POLICYDB_VERSION_XPERMS_IOCTL))) {
+ xperms.driver = xperms.specified;
+ if (android_m_compat_optype)
+ xperms.specified = AVTAB_XPERMS_IOCTLDRIVER;
+ else
+ xperms.specified = AVTAB_XPERMS_IOCTLFUNCTION;
+ avtab_android_m_compat_set();
+ } else {
+ rc = next_entry(&xperms.driver, fp, sizeof(u8));
+ if (rc) {
+ printk(KERN_ERR "SELinux: avtab: truncated entry\n");
+ return rc;
+ }
+ }
+ rc = next_entry(buf32, fp, sizeof(u32)*ARRAY_SIZE(xperms.perms.p));
+ if (rc) {
+ printk(KERN_ERR "SELinux: avtab: truncated entry\n");
+ return rc;
+ }
+ for (i = 0; i < ARRAY_SIZE(xperms.perms.p); i++)
+ xperms.perms.p[i] = le32_to_cpu(buf32[i]);
+ datum.u.xperms = &xperms;
+ } else {
+ rc = next_entry(buf32, fp, sizeof(u32));
+ if (rc) {
+ printk(KERN_ERR "SELinux: avtab: truncated entry\n");
+ return rc;
+ }
+ datum.u.data = le32_to_cpu(*buf32);
}
- datum.data = le32_to_cpu(*buf32);
if ((key.specified & AVTAB_TYPE) &&
- !policydb_type_isvalid(pol, datum.data)) {
+ !policydb_type_isvalid(pol, datum.u.data)) {
printk(KERN_ERR "SELinux: avtab: invalid type\n");
return -EINVAL;
}
@@ -504,18 +607,40 @@ bad:
int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp)
{
__le16 buf16[4];
- __le32 buf32[1];
+ __le32 buf32[ARRAY_SIZE(cur->datum.u.xperms->perms.p)];
int rc;
+ unsigned int i;
buf16[0] = cpu_to_le16(cur->key.source_type);
buf16[1] = cpu_to_le16(cur->key.target_type);
buf16[2] = cpu_to_le16(cur->key.target_class);
- buf16[3] = cpu_to_le16(cur->key.specified);
+ if (avtab_android_m_compat && (cur->key.specified & AVTAB_XPERMS) &&
+ (cur->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER))
+ buf16[3] = cpu_to_le16(avtab_xperms_to_optype(cur->key.specified));
+ else
+ buf16[3] = cpu_to_le16(cur->key.specified);
rc = put_entry(buf16, sizeof(u16), 4, fp);
if (rc)
return rc;
- buf32[0] = cpu_to_le32(cur->datum.data);
- rc = put_entry(buf32, sizeof(u32), 1, fp);
+
+ if (cur->key.specified & AVTAB_XPERMS) {
+ if (avtab_android_m_compat == 0) {
+ rc = put_entry(&cur->datum.u.xperms->specified,
+ sizeof(u8), 1, fp);
+ if (rc)
+ return rc;
+ }
+ rc = put_entry(&cur->datum.u.xperms->driver, sizeof(u8), 1, fp);
+ if (rc)
+ return rc;
+ for (i = 0; i < ARRAY_SIZE(cur->datum.u.xperms->perms.p); i++)
+ buf32[i] = cpu_to_le32(cur->datum.u.xperms->perms.p[i]);
+ rc = put_entry(buf32, sizeof(u32),
+ ARRAY_SIZE(cur->datum.u.xperms->perms.p), fp);
+ } else {
+ buf32[0] = cpu_to_le32(cur->datum.u.data);
+ rc = put_entry(buf32, sizeof(u32), 1, fp);
+ }
if (rc)
return rc;
return 0;
@@ -548,9 +673,13 @@ void avtab_cache_init(void)
avtab_node_cachep = kmem_cache_create("avtab_node",
sizeof(struct avtab_node),
0, SLAB_PANIC, NULL);
+ avtab_xperms_cachep = kmem_cache_create("avtab_extended_perms",
+ sizeof(struct avtab_extended_perms),
+ 0, SLAB_PANIC, NULL);
}
void avtab_cache_destroy(void)
{
kmem_cache_destroy(avtab_node_cachep);
+ kmem_cache_destroy(avtab_xperms_cachep);
}